2003
Blue Planet Prize
Dr. Gene E. Likens (U.S.A.)

Dr. Vo Quy (Vietnam)

President and Director, Institute of Ecosystem
Studies

Professor, Center for Natural Resources
Management and Environmental Studies,
Vietnam National University, Hanoi

Dr. F. Herbert Bormann (U.S.A.)
Oastler, Professor of Ecosystem Ecology,
Emeritus, Yale University

To the Earth, Our Home:
When did humanity begin to live
away from the ground that had
nurtured all life in the world
apart from other creatures? At
the 2003 Awards Ceremony of
the Blue Planet Prize of its12th
year, opening film expressed thedesire that humanity would takea new look at the planet earth, as
our home, the place for us toreturn to.

63

His Imperial Highness Prince Akishino
delivering congratulatory speech

Dr. Jiro Kondo, chairman of the Presentation Committee explains
the rationale for the determination of the year's winners
Dr. Hiroyuki Yoshikawa,chairman of the Selection
Committee makes a toast at
the Congratulatory Party

Their Imperial Highnesses Prince andPrincess Akishino at the Awards Ceremony

The prizewinners meet the press

Howard H. Baker Jr., Ambassador of theUnited States of America to Japan and
Vu Dung, Ambassador of Vietnam to
Japan, congratulate the laureates
The prizewinners receive their trophies from Chairman Seya

Dr. Gene E. Likens and
Dr. F. Herbert Bormann

64

Dr. Vo Quy

Profile

Dr. Gene E. Likens and Dr. F. Herbert Bormann
Dr. Gene E. Likens
President and Director, Institute of Ecosystem Studies
Dr. F. Herbert Bormann
Oastler, Professor of Ecosystem Ecology, Emeritus, Yale University

Dr. Gene E. Likens
Education and Academic and Professional Activities
1935
Born on January 6 in Pierceton, Indiana, USA
1957
Graduates from Manchester College
1962
Obtains his Ph.D. in Zoology, University of Wisconsin-Madison
1963
Instructor, Department of Biological Sciences, Dartmouth College, and prommoted to Assistant Professor
1969
Associate Professor, Section of Ecology and Systematics, Cornell University
1972-1983 Professor, Section of Ecology and Systematics, Cornell University
1983-1993 Vice President, The New York Botanical Garden
1983-present President and Director, Institute of Ecosystem Studies
1984-present Professor of Biology, Yale University
1985-present Professor, Graduate Field of Ecology, Rutgers University
1981
Elected, National Academy of Sciences
1993
Tyler Prize - (with Dr. F. H. Bormann)
1994
Australia Prize for Science and Technology
2001
National Medal of ScienceDr. F. Herbert Bormann
Education and Academic and Professional Activities
1922
Born on March 24 in New York City, New York, USA
1941
Enters the University of Idaho and mustered out of Navy
1946
Enters Rutgers University and graduates in 1948
1948
Enters Duke University and obtains his Ph.D. in 1952
1952
Assistant Professor, Emory University
1956
Assistant Professor, Dartmouth College
1962
Professor of Botany, Dartmouth College
1966-1992 Oastler Professor of Ecosystem Ecology, Yale University
1992-present Professor Emeritus and Senior Research Associate, Yale University
1973
Elected to the U. S. National Academy of Sciences

65

1992
1993

International St. Francis Prize for the Environment.
Tyler Prize. (with Dr. G. E. Likens)

The 40-year Hubbard Brook Ecosystem Study arose from an idea conceived by Dr. Bormann.
As a botany professor at Dartmouth College in 1960, he proposed to Dr. Robert S. Pierce(deceased), Project Leader of hydrologic station at the Hubbard Brook Experimental Forest(HBEF) of the U. S. Forest Service in the White Mountain National Forest in New Hampshire,that by measuring streamwater nutrient concentrations it would be possible to estimate nutrient outputs for entire forested watershed-ecosystems. This simple but powerful model allowed
the use of small watersheds to quantify the connection between forest ecosystems and thelarger biogeochemical cycles of the earth.
Gene E. Likens, who specialized in experimental limnology (the study of lakes andstreams) joined the faculty in the Department of Biological Sciences at Dartmouth College inthe fall of 1961. Thus, in a wonderful set of serendipitous circumstances, Bormann, a forest
ecologist, and Likens, an aquatic ecologist, joined forces.
Dr. Likens invited Dr. Noye M. Johnson (deceased), a geologist, to join in their proposal. In 1963, the National Science Foundation funded their proposal. Thus, The Hubbard
Brook Ecosystem Study was initiated.
In the 1960s, Drs. Bormann, Likens, Pierce, and Johnson formed the core of the small
group that initiated ecosystem and biogeochemical studies. The Hubbard Brook Ecosystem
Study continues to be productive and vibrant to this day.
As of 2003, more than 60 principal researchers have participated along with scores of
Ph.D. students, and research at Hubbard Brook has resulted in over 1,200 published articles
and six books.
Some of the major contributions of The Hubbard Brook Ecosystem Study to scienceand to the management of natural resources are as follows.
1. Research from The Hubbard Brook Ecosystem Study offered to the scientific community a new way to evaluate nutrient cycling in whole, intact or manipulated, terrestrial ecosystems.
2. Based on observation, experimentation and the Jabowa computer model, they developed a biomass accumulation curve for the northern hardwood forest. This finding
has great implications for estimates of the rates at which forests can remove carbon
dioxide from the atmosphere.
3. The HBES has demonstrated that the small watershed technique can be used to evaluate the effects on ecosystems of such factors as air pollution, timber harvesting, ice
storms, and climate change.
4. One experiment revealed that deforestation not only resulted in a large increase instream flow but also in loss of nitrate at rates 40 to 50 times higher than preharvest
levels. Long-term study indicated that nearly ten years were required for streams toreturn to preharvest levels. These findings resulted in a substantial national debate on
forest harvesting methods.

66

5. Discovery of acid rain in North America. The continuous analyses of precipitation
since 1963 demonstrated the link between the use of fossil fuels in North America
and increased acidification of rain and snow. This discovery prompted the world's
first international symposium on acid rain. These data subsequently contributed to the1990 Clean Air Act Amendments in the United States. Moreover, it made it clear thatacid rain leaches calcium from the forest soil. This leaching deprives the soil of nourishment and buffering capacity and causes major damage to forest and aquatic
ecosystems.
From the beginning of the HBES, Drs.Likens and Bormann, by a variety of means,seminars, and newspaper and magazine interviews, have tried to make the connection between
science and policy clear to the public. To achieve these ends, they joined with others to form
The Hubbard Brook Research Foundation which functions to connect science and policy.

67

EssaySurprises from Long-term Studies
at the Hubbard Brook Experimental Forest, USA
Dr. Gene E. Likens
Introduction
Long-term records of ecological phenomena are rare and very difficult to obtain, but they provide unique insights into how an ecosystem, if not the world, works. As such, these records
are a critical component of overall ecological inquiry (Likens 1989a, 1992; Carpenter 1998;
Lovett et al. 2006). Long-term records are usually developed through monitoring of ecosystem parameters (optimally guided by questions, not mindless collection of data), but statistically-valid records of high quality are difficult to develop and sustain over long periods. Thus,
there are relatively few records of long duration and high quality, which have had frequent andcareful scrutiny. Indeed, the integrity and application of quality assurance/quality control(QA/QC) protocols are key to the success of long-term studies (see Buso et al. 2000; Lovett etal. 2006; Hirsch et al. 2006). Without high quality QA/QC, long-term records are, for the mostpart, seriously compromised.
The pioneering efforts at Rothamsted, UK (Lawes Agricultural Trust 1984) and of theUnited States Weather Service come to mind as exemplary models. In the last 3 decades or soin the United States, there have been attempts to initiate and sustain long-term studies, e.g.
Long-Term Research in Environmental Biology (LTREB), Long-Term Ecological Research(LTER), Atmospheric Integrated Research Monitoring Network (AIRMoN), Clean Air Status
and Trends Network (CASTNeT). In spite of the documented value of such efforts (Likens
1989a) they are supported by fickle finances, and thus are difficult to maintain.
From a survey of some 100 ecologists involved in long-term research, Strayer et al.
(1986) found that the survival of long-term research was primarily dependent on the dedication and longevity of one or a few project leaders. Another key ingredient for maintaining longrecords of high quality is the frequent examination and use of these data, that is, this is the primary way that errors, artifacts, or other problems are discovered, and enthusiasm is sustained.
Moreover, it is much easier to resolve a problem in long-term data when it is identified in atimely fashion, while observers and methods are still available for examination. New sensors,
modified or new analytical procedures and real-time data can add significantly to long-term
data (Hirsch et al. 2006), but offsets and glitches generated by new methodology are a common problem in long-term data sets and must be addressed carefully. In the long-term
Hubbard Brook Ecosystem Study, we don’t replace an analytical method or a procedure witha new one without first overlapping the two for many months or more than a year in order tocompare results (Buso et al. 2000). Also, many samples are stored for later analysis to help

68

reconcile problems and to enable new questions to be pursued when new technology becomes
available (e.g. see Alewell et al. 1999). Some requirements for long-term studies are given in
Table 1.

Table 1. Requirements for long-term studies. [From Likens 2001b and based in part on Likens
1983 and modified from Likens 2001c].

(1)

Continuous data sets must be constantly updated, scrutinized for errors andrigorously reviewed.

(2)

Methods and procedures should be standardized to the extent possible, andintercalibrated with other organizations or individuals doing similar studies.
Calibration of analytical results should be done by comparison against standardized samples.

(3)

Full data sets should be stored in at least TWO separate locations to avoid
accidental loss.

(4)

Analytical methods or collection procedures should not be changed without
testing fully the effect of the new procedure on the long-term record.

(5)

Methods or procedures developed for one location or study should not be
adopted for another area or study without careful testing and justification.

(6)

The best frequency for sampling in a time series should be determined on thebasis of questions addressed and from analysis of results. Duration of measurements must be at least as long as the phenomenon being evaluated, or
scaled to the frequency of the event being studied.

(7)

Plots and other study sites should be marked and identified permanently.
Detailed descriptions of the area and the methodology should be on file inmore than one location. Sufficient detail should be provided so that otherinvestigators could reproduce calculations, methods, etc., at some later date.

(8)

Appropriate and adequate controls must be established at the beginning of
the study.

(9)

Provision should be made for the long-term storage of samples.

69

(10)

Stability, interest and dedication of responsible individuals, institutions or
agencies are critical to success of long-term studies.

(11)

Funding should be sustained and reliable.

(12)Long-term data sets should be used to answer questions.

Surprises Revealed From Long-Term Data at the Hubbard Brook Experimental Forest
There have been many new insights revealed from the examination of long-term data collectedin the Hubbard Brook Valley [43°56'N, 71°45'W] in the White Mountains of New Hampshire,
USA. Many of them were surprises to us about how ecosystems function, and were helpful inevaluating the effectiveness of Federal regulations. Currently, many ecological records in the
Hubbard Brook Valley extend for 55 years, and the continuous long-term records of precipitation and streamwater chemistry (43 years through May 2006) are the longest in the world.
Nevertheless, it could be argued convincingly that these records would be even more valuable
if they were twice as long, or more!
Surprises are defined as, something “to come or fall upon suddenly or unexpectedly” oranother definition that I like better is, “to strike with wonder and astonishment…, to astound.”(Webster’s New Universal Unabridged Dictionary, 2nd edition, 1983). The converse is; what
did we expect to find from long-term study that we did not find?
Here, I present a few brief examples of the more “astounding” results from the longterm efforts of the Hubbard Brook Ecosystem Study.
Acid Rain
Probably the biggest surprise from our long-term research at the Hubbard Brook Experimental
Forest was the discovery that “natural” rain was so acidic. The first sample of rain we collected
in July 1963 had a pH of 4.25! At the time we didn’t know why the rain was so acid, or what
it meant.
As part of our study’s protocol, samples of rain and snow were collected and chemicallyanalyzed in an effort to measure all inputs to the watershed-ecosystem at the Hubbard Brook
Experimental Forest (Bormann and Likens 1967). It required many years, discussions withcolleagues, and samples we collected in other areas of the northeastern U.S. before we understood that our results on rain from the Hubbard Brook Experimental Forest were an unusual
phenomenon of great ecological importance (Likens et al. 1972; Likens 1989b). Because of
the variability associated with weather, air-mass trajectories and diverse pollutant loadings tothe atmosphere, it required 18 years of continuous monitoring to determine statistically that theacidity of precipitation at the Hubbard Brook Experimental Forest had increased with time andin response to Federal legislation designed to reduce the emissions of sulfur dioxide (SO2) tothe atmosphere (Fig. 1) (Likens 1989b; Likens et al. 2001).

70

Short and Long-term H+ trends

Figure 1. Annual, volume-weighted hydrogen-ion concentration in bulk precipitation at the Hubbard Brook
Experimental Forest, New Hampshire. The line represents a linear regression at p<0.05 (updated from Likens
1989b).

Our long-term research now has contributed to the understanding of this environmental
problem and to the management of it. For example: long-term research at the Hubbard Brook
Experimental Forest has shown that: i. Changes in emissions of sulfur dioxide, SO2 (a major
precursor to acid rain), as a result of Federal legislation, are strongly correlated with changes
in sulfate concentrations in precipitation and stream water at the Hubbard Brook Experimental
Forest (Likens et al. 2001, 2002, 2005); ii. Nitric acid is increasing in importance in precipitation at the Hubbard Brook Experimental Forest and is predicted to be the dominant acid inprecipitation within 5 to 10 years without further controls on emissions of SO2 and NOx(Likens and Lambert 1998; Likens 2004); iii. In sharp contrast to predictions from the decadelong, U.S. National Acid Precipitation Assessment Program calcium and other plant nutrients
have been markedly depleted in the soils of the Hubbard Brook Experimental Forest as a resultof acid rain inputs (Likens et al. 1996, 1998); iv. As much as one-half of the pool of exchangeable calcium in the soil has been depleted during the past 50 years by acid rain (Likens et al.
1998); and v. As a result of these losses in soil buffering, the forest ecosystem is currently
much more sensitive to acid rain impacts than previously thought (Likens et al. 1996, 1998;
Likens 2004).
Depletion of Base Cations from the Soil
We were surprised to learn that acid rain had significantly depleted magnesium, and especiallycalcium from the soils at the Hubbard Brook Experimental Forest (Likens et al. 1996, 1998).

71

This depletion effectively increased the sensitivity of these soils to continuing inputs of acidfrom atmospheric deposition by depleting the buffering capacity of the soil. It is estimated thatsome 850 kg Ca/ha were leached from the soils of the Hubbard Brook Experimental Forest byacid rain between 1940 and 1990 (Likens et al. 1996, 1998).
Forest Biomass Accumulation
A truly surprising finding from the long-term studies at the Hubbard Brook Experimental
Forest was that the forest stopped accumulating biomass after 1982 (Fig. 2; Likens 2001b;
Likens et al. 1994, 1996, 1998).
Forest biomass accumulated steeply from 1965 to 1982, but since 1982, accumulation
has been flat, possibly even declining slightly (Fig. 2). This surprising result led to a wholestream manipulation and a major watershed manipulation with a calcium-rich mineral,
Wollastonite (CaSiO2), at the Hubbard Brook Experimental Forest in June 1999 and October
1999, respectively (Peters et al. 2004; Likens et al. 2004).

Figure 2. Accumulation of living, aboveground biomass for Watersheds 1 and 6 of the Hubbard Brook
Experimental Forest, New Hampshire (based on Whittaker et al. 1974; Bormann and Likens 1979; Likens et al.
1994; T. G. Siccama, unpublished data; and updated from Likens 2001b). The bar around each point represents thestandard error of the mean.

Algal Blooms
Some 40 years ago, careful examination revealed no algae in streams of the south-facing
watershed-ecosystems at the Hubbard Brook Experimental Forest. We were surprised by thislack of attached algae, but assumed that it was due to heavy shade from the surrounding forest
and low nutrient content of the stream water. In the mid 1980s, Mayer and Likens (1987)

72

found algae in Bear Brook and then Bernhardt and Likens (2004) observed blooms of attached,filamentous algae in headwater streams subsequent to snowmelt and prior to canopy leaf outof the deciduous forest on south-facing watershed-ecosystems. More recently, blooms ofattached algae have been observed in the main Hubbard Brook (Fig. 3), a fifth-order stream
draining the Hubbard Brook Valley. Possible explanations for this surprising change include
thinning of the overstory canopy due to increased tree mortality, which may result in warmer,
streamwater temperatures and more light reaching the stream earlier in the spring (Bernhardt
et al. 2005).

Figure 3. A photo of attached, filamentous algae in Hubbard Brook, a fifth-order river draining the Hubbard
Brook Valley, New Hampshire. (Photo by D. C. Buso on 28 April 2006).

Atmospheric Inputs and Watershed Nutrient Retention
Long-term studies revealed the surprising capacity of undisturbed, forested watershed-ecosystems to retain nutrients (e.g. N) critical to forest growth. Following disturbance (e.g. cutting,ice-storm damage, soil frost) large amounts of N may be lost in stream water (Likens et al.
1970; Bormann et al. 1974; Bormann and Likens 1979; Likens and Bormann 1995; Mitchell
et al. 1996; Houlton et al. 2003; Bernhardt et al. 2003). Retention in this case refers to net
retention (inputs from atmospheric deposition > losses in stream water).
Surprisingly, and in sharp contrast to predictions (Vitousek and Reiners 1975), NO3- levels in stream water at the Hubbard Brook Experimental Forest are currently at their lowest

73

value during our 43-yr record in spite of forest maturation and lack of biomass accumulation(Likens 2004; Bernhardt et al. 2005).
Other chemicals are also strongly retained by forested watershed-ecosystems at the
Hubbard Brook Experimental Forest including hydrogen ion, chloride and phosphorus (seeLikens and Bormann 1995; Likens 2004). Surprisingly, atmospheric deposition provides amajor source of these chemicals and others, to the watershed-ecosystems of the Hubbard
Brook Experimental Forest.
Significantly, ecologically important inputs of many nutrients in watershed-ecosystems,
including base cations (Ca2+, Mg2+, K+ and Na+), are derived from atmospheric deposition eventhough the primary source is weathering of geologic substrates (Likens and Bormann 1995;
Likens et al. 1994, 1998; Likens 2004; Gorham 1955).
Chloride as a Conservative Ion
Initially, our assumption was that chloride (Cl-) should be conservative (no long-term storage
or “sudden” release from storage pools). However, long-term studies surprisingly revealed
that Cl- is not conservative. For example, losses in stream water significantly increase following disturbance, such as forest cutting, in the Hubbard Brook Valley (Lovett et al. 2005).
This finding raises important questions about the biogeochemistry of Cl- and its use as a conservative tracer in experimental manipulations.
Ice Cover on Mirror Lake
Systematic observations on the duration of ice cover on Mirror Lake near the mouth of the
Hubbard Brook Valley were begun in the mid 1960s (Fig. 4). Surprisingly, with time the datewhen the ice cover (ice out) on the lake melted has occurred earlier each April, so that now theduration of ice cover on the lake during the winter is some 20 days less than it was in the mid
1960s (the date for the onset of ice cover each year has remained about the same). This surprising change has been related to global warming (Likens 2000), and has been found in otherlakes and rivers throughout the world (Magnuson et al. 2000).
What surprises are expected (an oxymoron) in the future? There probably will be many,
and a few are listed here:[1] Will depletion of Ca2+ and Mg2+ from the soil of the Hubbard Brook Experimental Forest
decline in response to reduced sulfur loading from the atmosphere and decreased storage of
Ca2+ and Mg2+ in forest biomass?
[2] Will the chemistry of the main Hubbard Brook (reflecting a valley-wide response) continue to change or reach a steady-state value as a result of reduced sulfur loading from theatmosphere?
[3] Will NO3- become the dominant acid anion in precipitation and what will be the ecological ramifications?
[4] Will NO3- concentrations in stream water increase during the growing season with the cessation of forest biomass accumulation.
High quality, long-term data, accumulated into the future, will be instrumental in
addressing these interesting and ecologically-important questions.

74

Figure 4. Duration of ice cover from 1967 to 2006 in days on Mirror Lake within the Hubbard Brook Valley. The
linear regression has a slope of -0.48 (r2 = 0.18; p = 0.009). [Updated from Likens 2000b].

Summary
There are many other “discoveries”/”surprises” from our long-term studies in the Hubbard
Brook Experimental Forest, but the examples given here are astonishing to me. Some additional discussion about our long-term results has been presented elsewhere (see, e.g. Likens
2004). Nevertheless the point is clear, long-term data and long-term studies are critical for
revealing ecosystem functions that either would be difficult to discover or possibly not revealed
from short-term studies.

References
Alewell, C., M. J. Mitchell, G. E. Likens and H. R. Krouse. 1999. Sources of stream sulfate at the Hubbard Brook
Experimental Forest: Long-term analyses using stable isotopes. Biogeochemistry 44:281-299.
Bernhardt, E. S. and G. E. Likens. 2004. Controls on periphyton biomass in heterotrophic streams. Freshwater
Biology 49:14-27.
Bernhardt, E. S., G. E. Likens, D. C. Buso and C. T. Driscoll. 2003. In-stream uptake dampens effects of major
forest disturbance on watershed nitrogen export. Proceedings of National Academy of Sciences 100(18):1030410308.
Bernhardt, E. S., G. E. Likens, R. O. Hall, Jr., D. C. Buso, S. G. Fisher, T. M. Burton, J. L. Meyer, W. H. McDowell,
M. S. Mayer, W. B. Bowden, S.E.G. Findlay, K. H. Macneale, R. S. Stelzer and W. H. Lowe. 2005. Can’t see
the forest for the stream? In-stream processing and terrestrial nitrogen exports. BioScience 55(3):219-230.
Bormann, F. H. and G. E. Likens. 1967. Nutrient cycling. Science 155(3761):424-429.
Bormann, F. H. and G. E. Likens. 1979. Pattern and Process in a Forested Ecosystem. Springer-Verlag New YorkInc. 253 pp.
Bormann, F. H., G. E. Likens, T. G. Siccama, R. S. Pierce and J. S. Eaton. 1974. The export of nutrients and recovery of stable conditions following deforestation at Hubbard Brook. Ecol. Monogr. 44(3):255-277.
Buso, D. C., G. E. Likens and J. S. Eaton. 2000. Chemistry of precipitation, streamwater and lakewater from the
Hubbard Brook Ecosystem Study: A record of sampling protocols and analytical procedures. General Tech.

75

Report NE-275. Newtown Square, PA: USDA Forest Service, Northeastern Research Station. 52 pp.
Carpenter, S. R. 1998. The need for large-scale experiments to assess and predict the response of ecosystems toperturbation. pp. 287-312. In: M. L. Pace and P. M. Groffman (eds.). Successes, Limitations, and Frontiersin Ecosystem Science. Springer-Verlag New York.
Gorham, E. 1955. On the acidity and salinity of rain. Geochim. Cosmoch. Acta 7:231-239.
Hirsch, R. M., P. A. Hamilton and T. L. Miller. 2006. U.S. Geological Survey perspective on water-quality monitoring and assessment. J. Environ. Monit. 8:512-518.
Houlton, B. Z., C. T. Driscoll, T. J. Fahey, G. E. Likens, P. M. Groffman, E. S. Bernhardt and D. C. Buso. 2003.
Nitrogen dynamics in ice storm-damaged forest ecosystems: Implications for nitrogen limitation theory.
Ecosystems 6(5):431-443.
Lawes Agricultural Trust. 1984. Rothamsted: the classical experiments. Rothamsted Agricultural Experiment
Station, Harpenden, England. 27 pp.
Likens, G. E. 1983. A priority for ecological research. Bull. Ecol. Soc. Amer. 64(4):234-243.
Likens, G. E. (ed.). 1989a. Long-Term Studies in Ecology. Approaches and Alternatives. Springer-Verlag New
York Inc. 214 pp.
Likens, G. E. 1989b. Some aspects of air pollution on terrestrial ecosystems and prospects for the future. Ambio
18(3):172-178.
Likens, G. E. 1992. The Ecosystem Approach: Its Use and Abuse. Excellence in Ecology, Vol. 3. Ecology
Institute, Oldendorf/Luhe, Germany. 167 pp.
Likens, G. E. 2000. A long-term record of ice cover for Mirror Lake, New Hampshire: effects of global warming? Verh. Internat. Verein. Limnol. 27(5):2765-2769.
Likens, G. E. 2001a. Biogeochemistry, the watershed approach: some uses and limitations. Marine andFreshwater Research 52(1):5-12
Likens, G. E. 2001b. Ecosystems: Energetics and Biogeochemistry. pp. 53-88. In: W. J. Kress and G. Barrett(eds.). A New Century of Biology. Smithsonian Institution Press, Washington and London.
Likens, G. E. 2001c. Eugene P. Odum, the ecosystem approach, and the future. pp. 309-328. In: G. W. Barrett
and T. L. Barrett (eds.). Holistic Science: The Evolution of the Georgia Institute of Ecology (1940-2000).
Taylor & Francis Publishing, New York.
Likens, G. E. 2004. Some perspectives on long-term biogeochemical research from the Hubbard Brook Ecosystem
Study. Ecology 85(9):2355-2362.
Likens, G. E. and F. H. Bormann. 1995. Biogeochemistry of a Forested Ecosystem. Second Edition, SpringerVerlag New York Inc. 159 pp.
Likens, G. E. and K. Fallon Lambert. 1998. The importance of long-term data in addressing regional environmental issues. Northeastern Naturalist 5(2):127-136.
Likens, G. E., F. H. Bormann, N. M. Johnson, D. W. Fisher and R. S. Pierce. 1970. Effects of forest cutting andherbicide treatment on nutrient budgets in the Hubbard Brook watershed-ecosystem. Ecol. Monogr. 40(1):2347.
Likens, G. E., F. H. Bormann and N. M. Johnson. 1972. Acid rain. Environment 14(2):33-40.
Likens, G. E., C. T. Driscoll, D. C. Buso, T. G. Siccama, C. E. Johnson, D. F. Ryan, G. M. Lovett, T. Fahey and
W. A. Reiners. 1994. The biogeochemistry of potassium at Hubbard Brook. Biogeochemistry 25:61-125.
Likens, G. E., C. T. Driscoll and D. C. Buso. 1996. Long-term effects of acid rain: response and recovery of a forest ecosystem. Science 272:244-246.
Likens, G. E., C. T. Driscoll, D. C. Buso, T. G. Siccama, C. E. Johnson, G. M. Lovett, T. J. Fahey, W. A. Reiners,
D. F. Ryan, C. W. Martin and S. W. Bailey. 1998. The biogeochemistry of calcium at Hubbard Brook.
Biogeochemistry 41(2):89-173.
Likens, G. E., T. J. Butler and D. C. Buso. 2001. Long- and short-term changes in sulfate deposition: Effects of
The 1990 Clean Air Act Amendments. Biogeochemistry 52(1):1-11.
Likens, G. E., C. T. Driscoll, D. C. Buso, M. J. Mitchell, G. M. Lovett, S. W. Bailey, T. G. Siccama, W. A. Reiners
and C. Alewell. 2002. The biogeochemistry of sulfur at Hubbard Brook. Biogeochemistry 60(3):235-316.
Likens, G. E., D. C. Buso, B. K. Dresser, E. S. Bernhardt, R. O. Hall, Jr., K. H. Macneale and S. W. Bailey. 2004.
Buffering an acidic stream in New Hampshire with a silicate mineral. Restoration Ecology 12(3):419-428.
Likens, G. E., D. C. Buso and T. J. Butler. 2005. Long-term relationships between SO2 and NOX emissions andSO42- and NO3- concentration in bulk deposition at the Hubbard Brook Experimental Forest, New Hampshire. J.
Environ. Monitoring 7(10):964-968.
Lovett, G. M., G. E. Likens, D. C. Buso, C. T. Driscoll and S. W. Bailey. 2005. The biogeochemistry of chlorineat Hubbard Brook, New Hampshire, USA. Biogeochemistry 72:191-232.
Lovett, G. M., D. A. Burns, J. Jenkins, M. J. Mitchell, L. Rustad, J. B. Shanley, C. T. Driscoll, G. E. Likens and R.
Haeuber. 2006. Who needs environmental monitoring? Submitted to Frontiers in Ecology and theEnvironment.

76

Magnuson, J. J., D. M. Robertson, B. J. Benson, R. H. Wynne, D. Livingstone, T. Arai, et al. 2000. Historical
trends in lakes and river ice cover in the Northern Hemisphere. Science 289:1743-1746.
Mayer, M. S. and G. E. Likens. 1987. The importance of algae in a shaded headwater stream as food for an abundant caddisfly (Trichoptera). J. N. Am. Benthol. Soc. 6(4):262-269.
Mitchell, M. J., C. T. Driscoll, J. S. Kahl, G. E. Likens, P. S. Murdoch and L. H. Pardo. 1996. Climatic control ofnitrate loss from forested watersheds in the Northeast United States. Environ. Sci. Technol. 30(8):2609-2612.
Peters, S. C., J. D. Blum, C. T. Driscoll and G. E. Likens. 2004. Dissolution of wollastonite during the experimental manipulation of Hubbard Brook Watershed 1. Biogeoche-mistry 67:309-329.
Strayer, D. L., J. S. Glitzenstein, C. Jones, J. Kolasa, G. E. Likens, M. McDonnell, G. G. Parker and S.T.A. Pickett.
1986. Long-term ecological studies: An illustrated account of their design, operation, and importance to ecology. Occasional Publication of the Institute of Ecosystem Studies, No. 2. Millbrook, New York. 38 pp.
Vitousek, P. M. and W. A. Reiners. 1975. Ecosystem succession and nutrient retention: a hypothesis. BioScience25(6):376-381.
Whittaker, R. H., F. H. Bormann, G. E. Likens and T. G. Siccama. 1974. The Hubbard Brook Ecosystem Study:
forest biomass and production. Ecol. Monogr. 44(2):233-254.

77

Lecture

Environmental Challenges in the 21st Century
and Our Respect for Nature
Dr. Gene E. Likens and Dr. F. Herbert Bormann
Introduction
We are deeply honored and proud to have been chosen for the Blue Planet Prize in 2003.
This prestigious honor reflecting the Asahi Glass Foundation’s goal to “work toward
protecting our planet from human-made demise, ensuring that the natural environment
continues to exist for tomorrow’s generations,” is especially meaningful to us after 40
years of research to understand how ecosystems work and how human activities may
disrupt their working to society’s disadvantage.
From a satellite our Blue Planet looks benign and placid as it hurtles throughhostile space. That view is deceiving as our planet’s surface is extraordinarily dynamic
with constant exchanges between it’s atmosphere, hydrosphere, geosphere, and biosphere.
It is upon these processes of exchange, mostly directly and indirectly driven by solar
energy, that all life depends and through time, evolution adapts life to new conditions as
our planet ages and moves toward some ultimate destiny (Figure 1).

Figure 1. Some uses of solar energy by the forest ecosystem in regulating ecosystem function and biogeochemical cycles. [Modified from Bormann 1985].

As human societies have evolved from hunter-gatherers to space travelers they havebecome a force of change with a potency equivalent to a major geological event like78

continental glaciation. As our human numbers and our skills increase and promise toincrease even faster in the 21st Century, and as our activities push wild nature more andmore into the background, thoughtful persons, scholars, scientists, laymen, businesspersons, theologians, and poets have begun to question how long this degradation cancontinue before human societies collapse in the face of some new environment we havecreated, an environment that may be inimicable to further growth of human societies or at
the least, inimicable to the sustenance of human dignity, which all humans seek.
Concepts of limits to growth and sustainable systems are being debated everywhere.
To evaluate such ideas, it has become apparent that we need much more information on
how the natural systems of the world work! This is an incredibly complex task involving
not only science but also economics, social studies and politics with the understandingthat answers must be in a systems format where changing one component will reverberate
throughout the ecosystem. The widespread public conception that science can provide
piecemeal “yes” or “no” answers has little applicability in understanding how the world
really works.
Vaclav Havel calls this the “Modern Age,” an “Age” with a central tenet of belief in
the inevitable dominance of humans over the rest of the world, a belief that the world is awholly knowable system governed by a finite number of laws that humans can grasp andrationally direct for their own benefit. The goal of science and technology in the “Modern
Age” is to find a universal theory of the world, and thus a universal key to unlock it’s
prosperity. Nature under this paradigm is a commodity to be bought, sold andmanipulated with little consideration of effects on naturally-occurring processes that in
the end govern how the world works.
The “Modern Age” began with the development of technology to use energy
locked in fossil fuels. Energy from fossil fuels freed humans from their sole dependence
on solar energy, the way of all previous human history, and opened exciting new areas ofactivity. This “Age,” which many regard as humanity’s finest hour, has been marked withan endless succession of human achievements. Science and technology have recorded
successes undreamt of in the Eighteen Century. Marvels of human infrastructure arefound everywhere in the world, health care and agriculture have made incredible advances,and we are now passing from the industrial revolution to the information revolution. In
material terms the quality of life for many people is at its highest level ever.
With this cornucopia of human benefits came the power to alter environmental
processes of the Earth in ways menacing to the survival of a great many organisms on theplanet. From the narrow perspective of human welfare, we might think of this response
as nature’s backlash to the “Modern Age.” Many fear that today’s level of environmental
degradation already threatens our human future.
Unlike any previous time in Earth’s history one species – humans – has come tomonopolize the use and availability of our planet’s resources. Humans now number morethan 6.3 billion and are expected to reach 8 to 10 billion in the next 50 years or so. Where
will this number find adequate and affordable supplies of fresh water, clean air andnourishing food? And, how will the distribution of wealth, natural resources and quality79

of life play out as humans increase in number, activity and interactions throughout the
globe? Questions such as these will drive major environmental challenges in the TwentyFirst Century.
Human-accelerated environmental change (Figure 2), such as global climatechange, toxification of the biosphere, the spread of infectious disease and alien species,
loss of biodiversity, and particularly the all-pervasive land-use changes are serious inthemselves, but their interactions and acceleration by human population growth andincreased activity of humans represent a daunting challenge for sustainability of all
species, including survival of human societies.

Figure 2. Interactions among the major components of human-accelerated environmental change. [Modified
from Likens 1994].

The study of ecosystems as units of nature provides critically important “windows”
on ecosystem function and on environmental problems and change. Currently, there isgreat demand for scientific information at large scales (the whole biosphere, regions andlandscapes), as often it is more realistic to apply information gained from large-scale
research to widespread environmental problems and management issues.
In 1960, F. Herbert Bormann in a letter to Robert S. Pierce, proposed the use ofsmall watershed-ecosystems for the study of ecosystem functions and the connection of
the ecosystem to the atmosphere and hydrosphere. But it was not until Gene E. Likens
and Herb Bormann, a plant ecologist, joined their diverse talents that the small watershed
technique became a functional reality. Likens, an aquatic ecologist, brought ecosystem
research experience, extraordinary energy, and what was to develop into a deep understandingof how a complex multidisciplinary study should be conducted.
Forty years ago, we instituted the small watershed-ecosystem approach to the studyof natural landscapes. Our approach allowed direct measurement of the linkage between
the atmosphere, the geosphere or watershed-ecosystem, and the hydrosphere. It allowed80

estimates of how the biosphere influenced these relationships. Answers to important
ecological questions about air and water quality, forest growth and sustainability, andecosystem structure and function in complicated natural landscapes are difficult to obtain.
We believed that the watershed-ecosystem approach would provide an important “window”
for tackling such problems.
Our initial approach to this conundrum took the form of an analogy. We postulated
that we could use the chemistry of stream water draining out of a watershed like thediagnostic approach a physician uses in measuring the chemistry of blood or urine of ahuman patient. We also needed to determine, simultaneously and quantitatively, allchemical inputs to the watershed-ecosystem (Figure 3). Such input-output measurementsallowed calculation of nutrient budgets (mass balances) for the ecosystem. Then, combinedwith experiments at the watershed scale, and because experimentation is such a powerfultool in science, we were able to address quantitatively, diverse environmental questions at
a watershed/landscape scale. Using this watershed approach, we launched the Hubbard
Brook Ecosystem Study.
Measurement of inputs to our small, naturally-occurring forest ecosystems (12 to
40 ha in size), provided a measure of how the atmosphere influenced the forest andinterlinked stream ecosystems through it’s input of rain, snow, particles and gases, andassociated chemicals. This feature of our research became of great importance since wequickly realized that the atmosphere was laden with pollutants from distant human activities.
The chemical and hydrological measurement of output waters allowed us todetermine how water passing through the watershed-ecosystem was altered by the
ecosystem and, in turn altered the ecosystem. Analysis of output water, like analysis ofblood and urine in humans, became a measure of the “health” of the ecosystem, providing
insights into the basic functions of the ecosystem. Since output water was linked to the
local and regional hydrosphere, our output measurements provided a means for evaluating
the effects of local ecosystem management on regional systems. Outputs of gases linked
to global atmospheric circulation. Collectively, linking the atmosphere, the hydrosphere,
the biosphere, and the implications of these linkages to ecosystem management provided
a powerful tool for thinking about local, regional, and global planning and development.
The value of this approach was stated in our first scientific publication in 1967, e.g.:“…the rate at which an ion is released by weathering (the breakdown of rockminerals) must equal its rate of net loss from the ecosystem plus its rate of net accumulationin the biota and organic debris.” …“Thus, net ionic losses from an undisturbed, relatively
stable terrestrial ecosystem are a measure of weathering within the system.”“Acceleration of losses or, more specifically, the disruption of local cycling patterns
by the activities of man could reduce existing ‘pools’ of an element in local ecosystems,
restrict productivity, and consequently limit human population.”81

Figure 3. Nutrient relationships in a terrestrial ecosystem. Inputs and outputs to the ecosystem are moved by meteorologic, geologic and biologic vectors (Bormann and Likens 1967; Likens and Bormann 1972). Major sites ofaccumulation and major exchange pathways within the ecosystem are shown. Nutrients that, because they have no
prominent gaseous phase, continually cycle within the boundaries of the ecosystem between the available nutrient,living and dead organic matter and primary and secondary mineral components, tend to form an intra-system cycle.
Fluxes across the boundaries of an ecosystem link individual ecosystems with the remainder of the biosphere.
[Modified from Bormann and Likens 1967].

Major Findings of the HBES
There have been numerous, extremely interesting, if not surprising discoveries from thelong-term research of the Hubbard Brook Ecosystem Study, including:• Using the small watershed approach and measurement techniques developed for the
Hubbard Brook Ecosystem Study, we established quantitative input-output budgets
for undisturbed northern hardwood forest ecosystems. Inputs demonstrated means bywhich the close and far environment could affect internal functions of the undisturbed
forest. Outputs from the ecosystem represented inputs for the myriad of near and far
ecosystems linked through movement of air and water, and demonstrated how theundisturbed forest ecosystem could affect interconnected aquatic ecosystems and theatmosphere.
• Through an experimental disturbance, clear cutting of the forest, we set in motion anarray of ecosystem processes, which revealed ecosystem responses to disturbance,
primarily loss of biological regulation of outputs, and with time after disturbance,
gradual recovery of biological regulation of outputs. The primary effect of deforestation was a severe reduction in evapotranspiration with a shift in evaporative water, agaseous loss, to runoff, a liquid loss, and to increased stormflow, a potentially destructive change in hydrology. A major finding was that forest cutting not only had a major
effect on hydrology, as expected, but also on microbial activity. Decomposition andespecially the process of nitrification were greatly accelerated with great productionof hydrogen and nitrate ions that facilitated extreme losses of nutrients in output

82

waters. Cutting and enforced devegetation also caused an increase of the erodibilityof the devegetated system with time. Other natural disturbances such as severe soil
freezing or ice storm damage also can increase nitrate loss in stream water from watershed-ecosystems. Our actual and theoretical work on the structure, function, anddevelopment of the northern hardwood forest ecosystem resulted in management protocols for forest harvest and long-term forest management.
• “Acid rain” in North America was discovered at the Hubbard Brook Experimental
Forest, and was shown to consist of acidified (pH less than 5.2) rain, snow, sleet andhail, fog and cloud water, and direct deposition of acidifying gases and particles. Aciddeposition has now been identified as a major environmental problem in widespreadareas of the world, including Europe and Asia. Long-term data from the Hubbard
Brook Experimental Forest provided important ecosystem understanding about aciddeposition, and information that subsequently was useful for development of a political resolution to this major environmental problem. This included information necessary for the passage of the Amendments to the Clean Air Act in 1990, which for the
first time in the U.S. focused on regulating the acid rain problem.
• Calcium and other plant nutrients have been markedly leached from the soils of the
Hubbard Brook Experimental Forest by acid deposition. As much as one-half of thepool of exchangeable calcium in the soil has been depleted during the past 50 years byacid deposition. As a result of these losses of nutrients and soil buffering capacity, theforest ecosystem in the northeastern U.S. is currently more sensitive to impacts of aciddeposition than previously thought.
• Based on observation and computer simulation, we designed a biomass accumulation
model for the northern hardwood forest. In contrast to other models of the time ourmodel demonstrated a substantial loss in net biomass following deforestation/clear
cutting before net biomass accumulation resumed. We used the model to develop a
realistic/theoretical description of the dynamics of disturbance, development and thesteady state of the northern hardwood forest ecosystem through time.
• Based on extensive and diverse experimental manipulations, it was learned that stream
ecosystems do not function like “Teflon pipes.” Instead, they are active sites of nutrient uptake and processing of nutrients and organic matter. Solute pulses added to
streams are rapidly attenuated as they move downstream. This attenuation of soluteadditions is the result of instream retention and processing, thereby reducing overall
net losses from the watershed.
• Computer simulation models were developed by our colleagues and applied as important research and predictive tools as part of the Hubbard Brook Ecosystem Study.
JABOWA, a forest growth simulator, was the forerunner of many subsequent models.
The BROOK model was developed to simulate and study forest hydrology. ALCHEMI,
CHESS and PnET-CBC have been important biogeochemical tools in the Hubbard
Brook Ecosystem Study and elsewhere.
• The Hubbard Brook Ecosystem Study demonstrated that changes in land-use can havemarked environmental effects on interconnected hydrologic ecosystems. A major

83interstate highway was constructed through the Mirror Lake watershed within the
Hubbard Brook Valley in 1969-1971. Subsequent application of large quantities ofsalt (NaCl) during winter to melt snow and ice on the roadway resulted in large andcontinuing increases in salt concentrations in the affected drainage stream and in thelake itself (chloride concentrations currently have increased by 20-fold and 4-fold in
the drainage stream and in Mirror Lake, respectively). This quantitative illustration of
the environmental effects of road salt on interconnected aquatic ecosystems, seems
particularly significant since some 10 million tons of salt are applied to U.S. roads inthe winter.
One of the most profound ideas to have come from the long-term measurements atthe Hubbard Brook Experimental Forest, especially of experimentally manipulated
systems, is that complex legacies play out over very long periods of time. Each
disturbance creates a set of conditions or trajectories that impacts the next situation, andthus, the sum total of ecosystem processes is influenced by historical events, each event
being overlaid on some previous one. Our long-term ecological and biogeochemical datafrom the Hubbard Brook Ecosystem Study have been invaluable for unraveling suchlegacy effects, as well as for providing continuity for examination of critical questions,for identifying extreme events, for generating new research questions, for detecting
environmental change, and for providing knowledge needed by decision makers. The
long-term ecological and biogeochemical record at the Hubbard Brook Experimental
Forest increases in intrinsic value with every year of record added to it. Some examplesof our long-term studies include:— Declines in emissions of lead, associated with the elimination of leaded fuels in
the U.S. were correlated with a marked decrease of lead in precipitation and in
the forest floor at the Hubbard Brook Experimental Forest. These data helped
confirm the efficacy of regulations against the use of leaded gasoline in the U.S.;— Enigmatically, net accumulation of forest biomass has ceased since 1982 at the
Hubbard Brook Experimental Forest. Is this result some complicated effect ofacid rain? Failure of the northern hardwood forest ecosystem to grow could
have serious implications for the sustainability and harvest of forest landscapesin the northern U.S. This important question is the subject of intense, ongoinginvestigation.
— Long-term studies of Mirror Lake during winter show that the duration of ice
cover is becoming significantly shorter each year. This decrease in ice cover is
one clear measure of global climate change.
— Organic debris dams, naturally formed in streams in a forest landscape, playmajor functional roles in the ecology and biogeochemistry of stream ecosystems.
It was found that 100 years or more are required for organic debris dams inheadwater streams to reform following their loss due to disturbance fromdeforestation.
— Initial models of the rate of return to steady-state conditions in forest ecosystems

84following clear cutting involved measurement of solutes in stream water exiting
the watershed-ecosystem. For ions such as nitrate, calcium and potassium, there
were large net losses peaking in the second year after cutting. Thereafter,
streamwater losses declined as the vegetation recovered and net losses ofdissolved chemicals returned to near pre-cutting levels at rates unique to eachion. For the purposes of understanding the ecosystem effects of forest cutting
and for planning future forest management strategies, these data were clear andsufficient. Yet, decades after these experimental clear cuts were done within the
Hubbard Brook Experimental Forest, subtle to large differences still can be seen
in several streamwater solutes, such as calcium. Understanding gained from ourlong-term element mass-balance analyses suggests that the legacy from the
1965-66 cut was still affecting ecosystem function in 2003!
It is not possible here to describe the major results of numerous other research
efforts at the Hubbard Brook Experimental Forest over the years, including the importantstudies of bird populations and dynamics, studies of the ecology, biogeochemistry andhydrology of stream and lake ecosystems [see www.hubbardbrook.org/research/current/
projects/ streams/stream_99.htm], studies of pattern and process in the northern hardwood
forest ecosystem, and experimental ecosystem (“Sand Box”) studies.
Management of the HBESLong-term continuity of a complex study, such as the Hubbard Brook Ecosystem Study,
involves much more than science alone. Several management features and goals were
fundamental to sustaining the productivity and integrity of the Hubbard Brook Ecosystem
Study over such a long period (40 years); (1) developing at the outset and continuing touse a conceptual biogeochemical model (Figure 3) for guiding research and ecosystemanalysis; (2) nurturing a strong incentive within our team to understand the whole system(the ecosystem) rather than a reductionist approach of focusing exclusively on thecomponents (parts) of the system; (3) integrating results and preparing synthesis volumes
as rapidly as possible (see www.hubbardbrook.org/research/pubs/hbrbib.htm); (4)nurturing the concept of long-term studies even though it was often difficult to maintain
uninterrupted funding; (5) enticing outstanding, senior colleagues from a variety of
disciplines to join our scientific team; (6) maintaining a small, focused and dedicatedteam of researchers that spent much time in residence, interacting together at the Hubbard
Brook Experimental Forest; and (7) developing analytical procedures that were neither
changed nor replaced without first overlapping and comparing results from the “long-term
method” with those from a proposed new method. This procedure helped to avoid“artifacts” in the long-term data. Any such changes were carefully documented.
We believe that these management approaches to our science were central to thesuccesses we have had. Additional detail on our operating and management philosophy
for the Hubbard Brook Ecosystem Study was given in the Prefaces to our first two
synthesis volumes:

85

Likens, G. E., F. H. Bormann, R. S. Pierce, J. S. Eaton and N. M. Johnson. 1977.
Biogeochemistry of a Forested Ecosystem. Springer-Verlag New York Inc. 146
pp.
Bormann, F. H. and G. E. Likens. 1979. Pattern and Process in a Forested Ecosystem.
Springer-Verlag New York Inc. 253 pp.
Long-Term Studies
Long-term data can be used to evaluate the biogeochemical response to and recovery
from disturbance, such as from acid rain, forest cutting, ice storms and from experimental
watershed manipulations. Such long-term records are critical for developing biogeochemical
trends and for understanding complicated changes in ecosystem structure and function.
These qualitative and quantitative records provide hard information for decision makers
wrestling with understanding and solving major environmental issues.
Three examples of our long-term studies are presented here in more detail.
Acid Rain
The primary source of acid rain (atmospheric deposition of acidified rain, snow, sleet,hail, cloud and fog water and acidifying gases and particles) is the combustion of fossil
fuels, which releases of sulfuric dioxide (SO2), nitrogen oxides (NOx) and particles to theatmosphere. The SO2 and NOx may be converted in the atmosphere to sulfuric and nitricacids, and along with the gases themselves and acidifying particles, are eventually
returned to the Earth’s surface. These inputs acidify some terrestrial and aquatic
ecosystems resulting in diverse impacts including the loss of species and accelerated
leaching of nutrients, such as calcium. Acid rain is a relatively recent environmental
problem, now spread widely around the world and particularly in eastern North America,
northwestern Europe and southeastern Asia.
We learned from the very first sample of rain we collected at the Hubbard Brook
Experimental Forest in June 1963 that the rain was acid, but it took several years to
discover the cause and the nature of its widespread occurrence. Acid rain represents anexperiment at a grand scale being imposed by humans on diverse ecosystems around theworld.
As combustion of fossil fuels increased in the U.S. following the Industrial Revolution,
emissions of SO2 and NOx increased. Recently, atmospheric emissions of SO2 and small
particles have decreased in the U.S. due to Federal regulation. In contrast, NOxemissions, which are largely unregulated, have increased (Figure 4). Sulfuric acid has
been the dominant acid in precipitation at the Hubbard Brook Experimental Forest since1963, but nitric acid is expected to be the dominant acid in the next decade or so. Thischange is likely to have significant ecological and biogeochemical consequences onrecipient ecosystems.

86

Figure 4. Long-term trends in emissions of sulfur dioxide, nitrogen oxides and particulate matter (10 µm in diameter) from the Hubbard Brook Experimental Forest source area (updated from Butler et al. 2001; Likens et al.
2001).

Undoubtedly, the amount and mix of emissions will continue to change in the U.S.
as a result of changing energy demand and pending federal and state actions. Given thecost and angst involved with this legislation since the mid 1960’s, it is important tomeasure the legislation’s impact on atmospheric deposition and on recipient forest andaquatic ecosystems that have now become highly sensitive to these acidic inputs.
The causes, distribution and effects of acid deposition have been aggressively
studied and debated in North America for three decades following our publication in
1972, which identified this problem in North America. Federal regulations to control air
pollution in the U.S. were significantly strengthened and enlarged in 1970 primarily to
reduce particulate emissions, but the Amendments to the Clean Air Act (CAAA) in 1990
were the first national legislative initiative, which focused directly on the problem of acidrain. Significant reductions of SO2 emissions did not occur until 1995 when implementationof Phase I of the CAAA caused a decline in U.S. emissions equivalent to ~40% of theoverall reduction targeted by the CAAA.
An extremely important finding from the long-term data at the Hubbard Brook
Experimental Forest was the clarification of the relationship between gaseous emissions(SO2) and concentrations of sulfate dissolved in precipitation. This contentious issue had
dominated the national debate during the 1980’s in the absence of long-term data. We
found that both precipitation and streamwater concentrations of sulfate are significantly
correlated with emissions of SO2 from the source area upwind of the Hubbard Brook
Experimental Forest (Figure 5). Atmospheric deposition of nitrate (another acidifying
anion) also is correlated with NOx emissions. Moreover, there is a strong correlation(r2=0.76) between the decrease in streamwater concentrations of sulfate observed at the
Hubbard Brook Experimental Forest and the decrease in base cations (calcium, magnesium,
sodium and potassium) concentrations in stream water. This is an important finding as
the base cations control the acid-neutralizing capacity or alkalinity of the ecosystems inthe Hubbard Brook Experimental Forest.

87Figure 5. Annual sulfur dioxide (SO2) emissions vs. sulfate (SO42-) concentrations in precipitation at the Hubbard
Brook Experimental Forest (updated from Likens et al. 2001).

Our long-term research has greatly advanced the knowledge base needed fordeveloping policy and Federal legislation related to air pollution. For example:• Changes in emissions of sulfur dioxide, SO2, as a result of Federal legislation, arestrongly and linearly correlated with changes in sulfate concentrations in precipitationand stream water at the Hubbard Brook Experimental Forest. Thus, reducing emissions of SO2 will directly reduce inputs of acidifying sulfate.
• Eighteen years of continuing study were required to verify that the acidity of precipitation had decreased at the Hubbard Brook Experimental Forest (Figure 6). The acidity of precipitation increased from about 90 µeq H+/liter in the mid 1960’s to about 55µeq H+/liter in the late 1980’s. However, current values are still about 8 times moreacid than if the precipitation were not polluted (about 5 µeq H+/liter).

Figure 6. Long-term trends in hydrogen ions in precipitation at the Hubbard Brook Experimental Forest.

88• Nitric acid is increasing in importance in precipitation at the Hubbard Brook
Experimental Forest and is predicted to be the dominant acid in precipitation by 20102015 without further controls on emissions of SO2 and NOx.
• Calcium and other plant nutrients have been markedly depleted in the soils of the
Hubbard Brook Experimental Forest as a result of acid deposition.
— As much as one-half of the pool of exchangeable calcium in the soil has
been depleted during the past 50 years by acid deposition. These losses
may be affecting the biological productivity of the ecosystem.
— As a result of these losses in soil buffering, the forest ecosystem iscurrently more sensitive to acid deposition impacts than previously
thought.
The Hubbard Brook Experimental Forest is an important site for monitoring
atmospheric pollutants in the northeastern U.S. because of the long and high-quality
record of precipitation chemistry, its location “downwind” of major sources, and lack of
local, major sources of pollution.
We have initiated a whole watershed manipulation to test experimentally some of
the long-term effects of acid deposition on the ecosystems at the Hubbard Brook Experimental
Forest. A natural calcium silicate mineral (Wollastonite) was mined in the Adirondack
Mountains of New York State, pulverized, pelletized and then added to a watershedecosystem at the Hubbard Brook Experimental Forest by helicopter in 1998. An amountof calcium estimated to have been depleted from the ecosystem during the past 50 years
was added in this manipulation. It is planned to study the effect of this experimental
manipulation on stream and soil chemistry, tree growth, animal populations, microbialactivity and other aspects of ecosystem structure and function over the next 50 years!
Effects of Forest Disturbance, Such as Cutting, on Ecosystem Dynamics at theWatershed Scale
Entire-watershed, experimental manipulations have been a powerful analytical tool of the
Hubbard Brook Ecosystem Study. In the words of a colleague, W. Lewis, “Watershedmanipulation now is a standard part of the biogeochemist’s repertoire, but in the 1960s it
must have seemed radically intrusive and perhaps even a bit pushy. . . (Experimental)
manipulation, as we now know, vastly accelerates the pace of discovery, and that was oneof the secrets of success for what became known as the Hubbard Brook Ecosystem
Study”. The ability to do such large-scale, experimental manipulations on a long-termbasis, with adjacent watersheds for reference, indeed was one of the scientific joys andsuccesses of the Hubbard Brook Ecosystem Study.
We discovered that cutting the forest sets in motion an amazing array of changes inecosystem processes and interactions with concomitant changes in environmental conditions(Figure 7). Watershed 2 was deforested in 1965-66 – no trees were removed, and thewatershed was treated with herbicides during summers of 1966, 1967 and 1968. As a resultof this experimental manipulation, microbially-dominated processes: decomposition,mineralization and nitrification, were accelerated; ecosystem processes governing the loss89

of evaporative water to the air (transpiration) were markedly slowed; streamflow, theprocess whereby water is removed from the ecosystem was greatly increased as water
previously evaporated by the intact forest became liquid water; sunlight energy previouslyintercepted and partly reflected back the atmosphere now was intercepted by the forest
floor where it warmed the soil; concentrations of dissolved substances (nutrients) in thesoil solution rose dramatically as a result of increased microbial activity combined withgreatly diminished uptake by the trees that had been cut. This set of interactions within
the northern hardwood ecosystem, triggered by our experimental clear cut, illustrates thecomplex nature of ecosystem behavior. This complexity is greatly deepened with therealization that for each research question answered, two or more arise.

Figure 7. Major hydrologic and biologic responses of the northern hardwood forest ecosystem during the first two
years after cutting. The erosion response assumes little damage to the soil during the harvesting process. Responses
in double-lined boxes represent marked increases in resource availability within the ecosystem following disturbance. [Modified from Bormann and Likens 1979].

Effect of Climate Change
Currently, one of the most vexing problems in environmental science is how to determine
the rate and effect of global climate change. Specifically in our case, is climate changing
at the Hubbard Brook Experimental Forest, and if so, what are the impacts of climatechange on ecosystem structure and function?
Changes in the heat budget of lakes reflect long-term changes in climate. Because
duration of ice cover is a significant component of the annual heat budget of northern
Temperate lakes, changes in duration of ice cover can be used as an important measure ofchanges in climate. Uniquely reliable records of ice IN and ice OUT dates exist for
Mirror Lake since 1968. The error of the ice IN date is ± 2 days and for ice OUT date is± 1 day. Thus, both the length and quality of the record for Mirror Lake are unusual.

90

The duration of ice cover on Mirror Lake has declined at a significant (p<0.016) rate ofabout 0.5 days per year during the past 36 yr, or currently ice cover exists on the lake forabout 19 days less than it did in 1967 (Figure 8). This trend of decreasing ice cover on
Mirror Lake is the result of the ice melting earlier (earlier ice OUT dates), which iscorrelated with increased air temperatures in spring and cloudier spring weather at the
Hubbard Brook Valley during this 36-yr period.
The long-term record of ice-cover on Mirror Lake provides an important contribution
to the debate on global climate change, and indicates that our region is indeed undergoingwarming. Decreasing ice cover has been found on lakes in other regions of the world.
An important question now under investigation in the Hubbard Brook Valley is, what are
the biological implications of climate change on local aquatic and terrestrial ecosystems?

Figure 8. Annual duration of ice cover in days on Mirror Lake since 1967 [updated from Likens 1999]

The Future of the Hubbard Brook Ecosystem Study
It is extremely difficult, if not impossible, to predict the future, particularly in these
uncertain times. Nevertheless, the long-term chemical record combined with the longterm hydrologic record and stable research infrastructure provided by the USDA Forest
Service at the Hubbard Brook Experimental Forest have served, and are likely to serve
well into the future, as a magnet for research and researchers of the Hubbard Brook
Ecosystem Study. There is no lack of exciting questions and research opportunities forstudies of ecosystem structure and function, and biogeochemistry. Some difficult biogeochemical problems that we have wrestled with for 40 years, will continue well into the
future, e.g. dynamics of the N cycle (fixation, denitrification and ecosystem retention);elaboration of the weathering process; impacts of acid deposition, and many newquestions that will emerge (Table 1). Dozens of senior scientists, students and technicians
conduct research at the Hubbard Brook Experimental Forest every year. It seems likelythat they will do so for at least another 40 years, and will be driven by persistent questions

91

that remain vital to science and society, and by new questions that are generated from thelong-term data and from the effects of new perturbations imposed on this mostremarkable and valuable Valley.

Table 1.

Some major challenges for biogeochemical studies in the future [modified from Likens 2003].

1. What are the specific effects and relationships of the increasing size of thehuman population on the biogeochemical flux and cycling of elements, andthe effects of forcing functions often incongruent in space and time?
2. What controls fluxes of N and P to and from natural and human-dominated(cities, agricultural) ecosystems?
3. What is and what controls C sequestration in diverse ecosystems (e.g. forest,
ocean, lakes, wetlands) on variable temporal and spatial scales?
4. What controls weathering rates, and what are the fates of the weatheredproducts, including nutrient loss in terrestrial ecosystems?
5. What are the quantitative interrelationships between hydrology, ecology andbiogeochemistry?
6. How can a better synoptic understanding of the biogeochemical flux, cycling
and interaction of elements among air, land and water (including ocean)systems be achieved?
7. What are the critical linkages and feedbacks among major nutrient and toxic
element fluxes and cycles?

Respect for Nature
In every quarter of the globe, in every culture and ethnicity and among many, but by nomeans all, there is a deep respect for nature (Bormann 2000). This respect, based on
beauty and to some degree appreciation of how the natural world works, finds it’s
expressions in art, literature, architecture, taboo’s of all societies.
We believe that our work adds a new and important dimension to the concept of“Respect for Nature.” Studies by colleagues and us blossomed with more than a92

thousand scientific publications during the last four decades and, with that blossoming,
our perception of the forest landscape has changed. Today, there is still the beauty andmagnificence of the forest landscape, but now there is more. Despite the seeming quiet ofthe forest, there is a sense of being surrounded by an enormous dynamism: thousands ofliters of water and tons of chemicals stream upward through tree trunks, photons ofenergy are absorbed by leaves and put to work evaporating water through leaves andfixing energy in organic compounds, food manufactured in leaves stream to growing
points, insect predators quietly nibble away, rocks are broken down into useable nutrients,
microbes disassemble organic compounds and free nutrients for reuse, all species play out
their roles in reproduction, the forest ecosystem grudgingly restocks the forest stream
with water, the stream ecosystem uses and recycles nutrients and organic matter from thewater on its ultimate journey downhill, and a million other things occur simultaneously.
Our concept of beauty changed with the realization that visual beauty can beenhanced or surpassed by unseen corroborative pictures flashing across the screen we call
our consciousness. Despite our growing knowledge of the natural world, there is still avast unknown component to the Earth whose extent and effectiveness is supported every
day as this BLUE planet sails through forbidding space. We should respect, cherish andchange with utmost caution this largely unknown natural world because it works as it
does, and we are totally dependent on this “working.”
Rather than waging a “war on nature”, it is important to incorporate aspects ofhumility and respect for nature in our daily lives if we are to achieve some measure ofsustainability. We must make a major shift in our thinking and in our actions from a
consumer society to what J. H. Gibbons calls a “conservator society.” Some componentsof respect for nature include:• Respect for nature’s complexity• Respect for nature’s resilience and fragility• Respect for nature’s changing structure and function• Respect for what nature does for us every second of the day providing clear air, cleanwater and clean and nourishing food, and much more.
• Respect for the conservation of nature’s great regenerative powers
References
Bormann, F. H. 1985. Air pollution and forests: an ecosystem perspective. Bioscience 35(7):434-441.
Bormann, F. H. 1996. Ecology: A personal history. Annual Review of Energy and Environment 21:1-29.
Bormann, F. H. 2000. On respect for nature. Northern Rockies Conservation Cooperation News, Autumn 2000,
No. 13. (P.O. Box 2705, Jackson, WY 83001)
Bormann, F. H. 2001. Confronting the environmental debt. Mimeo. Library, Yale School of Forestry andEnvironmental Studies.
Bormann, F. H. and G. E. Likens. 1967. Nutrient cycling. Science 155(3761): 424-429.
Bormann, F. H. and G. E. Likens. 1979. Pattern and Process in a Forested Ecosystem. Springer-Verlag New YorkInc. 253 pp.
Butler, T. J., G. E. Likens and B.J.B. Stunder. 2001. Regional-scale impacts of Phase I of the Clean Air Act
Amendments: The relation between emissions and concentrations, both wet and dry. Atmospheric Environment
35(6):1015-1028.
Likens, G. E. 1994. Human-Accelerated Environmental Change – An Ecologist's View. 1994 Australia Prize
Winner Presentation. Murdoch University, Perth, Australia. 16 pp.

93

Likens, G. E. 2000. A long-term record of ice cover for Mirror Lake, New Hampshire: effects of global warming? Verh. Internat. Verein. Limnol. 27(5):2765-2769.
Likens, G. E. 2003. Biogeochemistry: Some opportunities and challenges for the future. Biogeomon Special
Issue, Water, Air and Soil Pollution: Focus (In Press)
Likens, G. E. and F. H. Bormann. 1972. Nutrient cycling in ecosystems. pp. 25-67. In: J. Wiens (ed.). Ecosystem
Structure and Function. Oregon State Univ. Press, Corvallis.
Likens, G. E., T. J. Butler and D. C. Buso. 2001. Long- and short-term changes in sulfate deposition: Effects of
The 1990 Clean Air Act Amendments. Biogeochemistry 52(1):1-11.

94

Acknowledgements
We are pleased to acknowledge the many undergraduate, graduate and postdoctoral
students, research technicians and colleagues that have contributed to the Hubbard Brook
Ecosystem Study during the past 40 years. As an ecosystem study, the HBES depends
heavily on cooperation, trust and interaction. These features and the scientific talents andenthusiasm of our many colleagues have contributed in major ways to the long-term
successes of the Hubbard Brook Ecosystem Study. We are pleased to acknowledge heresome of our senior, long-term colleagues:
Bernard T. Bormann [USDA Forest Service]; W. Breck Bowden [Univ. Vermont];
Donald C. Buso [Institute of Ecosystem Studies]; Margaret B. Davis [University of
Minnesota]; Dr. Charles T. Driscoll [Syracuse University]; Christopher Eagar [USDA
Forest Service]; John S. Eaton [Institute of Ecosystem Studies (deceased)]; Timothy J.
Fahey [Cornell University]; C. Anthony Federer [USDA Forest Service]; Donald W.
Fisher [USGS]; Peter M. Groffman [Institute of Ecosystem Studies]; Richard T. Holmes[Dartmouth College]; James W. Hornbeck [USDA Forest Service]; Noye M. Johnson[Dartmouth College (deceased)]; C. Kent Keller [Washington State University]; Thomas
Ledig [Yale University]; Gary M. Lovett [Institute of Ecosystem Studies]; C. Wayne
Martin [USDA Forest Service]; Robert S. Pierce [USDA Forest Service (decreased)];William Reiners [University of Wyoming, Laramie], Nick Rodenhouse [Wellesley
College]; Don Rosenberry [USGS]; Thomas Sherry [Tulane University]; Thomas Siccama[Yale University]; William Smith [Yale University]; Franklin Sturges [Shepardstown
College]; Deane Wang [University of Vermont]; Kathleen C. Weathers [Institute of Ecosystem
Studies]; Robert H. Whittaker [Cornell University (decreased)]; Thomas C. Winter [USGS]
Generous financial support over the years was provided by the National Science
Foundation, The Andrew W. Mellon Foundation, the Mary Flagler Cary Charitable Trust,and the Environmental Protection Agency.

95

Major Publications
Dr. Gene E. Likens
Books:
1.
2.
3.
4.

5.
6.
7.
8.
9.
10.
11.

12.
13.
14.

15.
16.
17.

Likens, G. E. (ed.). 1972. Nutrients and Eutrophication. American Society of Limnology andOceanography, Special Symposia. Lawrence, Kansas. Volume I. 328 pp.
Likens, G. E., F. H. Bormann, R. S. Pierce, J. S. Eaton and N. M. Johnson. 1977.
Biogeochemistry of a Forested Ecosystem. Springer-Verlag New York Inc. 146 pp.
Bormann, F. H. and G. E. Likens. 1979. Pattern and Process in a Forested Ecosystem. Springer-Verlag
New York Inc. 253 pp.
Rodhe, W., G. E. Likens and C. Serruya (eds.). 1979. Lake Metabolism and Management. Papers
Emanating from the Limnological Jubilee Symposium of Uppsala University (1477-1977), Sweden.
Ergebnisse Limnol. Arch. Hydrobiol. 13.
Wetzel, R. G. and G. E. Likens. 1979. Limnological Analyses. W. B. Saunders Co., Philadelphia. 357
pp.
Likens, G. E. (ed.). 1981. Some Perspectives of the Major Biogeochemical Cycles, Vol. 17. SCOPE
IVth General Assembly, Stockholm, Sweden. John Wiley & Sons Ltd., Chichester. 170 pp.
Likens, G. E. (ed.). 1985. An Ecosystem Approach to Aquatic Ecology: Mirror Lake and Its
Environment. Springer-Verlag New York Inc. 516 pp.
Likens, G. E. (ed.). 1989. Long-Term Studies in Ecology. Approaches and Alternatives. SpringerVerlag New York Inc. 214 pp.
Wetzel, R. G. and G. E. Likens. 1991. Limnological Analyses. Second Edition. SpringerVerlag New York Inc. 391 pp.
Likens, G. E. 1992. The Ecosystem Approach: Its Use and Abuse. Excellence in Ecology,
Vol. 3. Ecology Institute, Oldendorf/Luhe, Germany. 167 pp.
Train, R. E., P.A.A. Berle, J. E. Bryson, A. W. Clausen, D. M. Costle, M. M. Kunin, G. E.
Likens, C. A. Matos, G. S. Omenn, P. H. O'Neill, A. M. Rivlin, P. Robinson, S. C.
Rockefeller, W. D. Ruckelshaus, G. R. Scott, J. G. Speth, L. M. Thomas, V. J.
Tschinkel and R. M. White. 1993. Choosing a Sustainable Future. The Report of the National
Commission on the Environment. Island Press, Washington, DC. 180 pp.
Groffman, P. M. and G. E. Likens (eds.). 1994. Integrated Regional Models: Interactions
Between Humans and Their Environment. Chapman & Hall, New York. 157 pp.
Likens, G. E. and F. H. Bormann. 1995. Biogeochemistry of a Forested Ecosystem.
Second Edition, Springer-Verlag New York Inc. 159 pp.
Pickett, S.T.A., R. S. Ostfeld, M. Shachak and G. E. Likens (eds.). 1997. The Ecological
Basis of Conservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall, New York.
466 pp.
Wetzel, R. G. and G. E. Likens. 2000. Limnological Analyses. Third Edition. SpringerVerlag New York Inc. 429 pp.
Weathers, K. C., D. L. Strayer and G. E. Likens (Eds.). 2006. Fundamentals of Ecosystem Science.
Elsevier Academic Press [In Press]
Winter, T. C. and G. E. Likens (eds.). 2006. Dynamics of Lake, Watershed and Atmospheric Linkages.
University of California Press (In Preparation)

Publications:
1.
Likens, G. E. and A. D. Hasler. 1960. Movement of radiosodium in a chemically stratified lake.
Science 131(3414):1676-1677.
2.
Likens, G. E. and A. D. Hasler. 1962. Movements of radiosodium (Na24) within an ice-covered lake.
Limnol. Oceanogr. 7(1):48-56.
3.
Hasler, A. D. and G. E. Likens. 1963. Biological and physical transport of radionuclides in stratified
lakes. pp. 463-470. In: V. Schultz and A. W. Klement, Jr. (eds.). Radioecology. American Institute of

96

4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.

16.

17.
18.

19.
20.
21.
22.

23.

24.
25.
26.
27.

Biological Sciences and Reinhold Publ. Corp., New York.
Likens, G. E. 1964. An unusual distribution of alge in an Antarctic lake. Bull. Torrey Bot. Club
91(3):213-217.
Likens, G. E. 1964. Pesticide pollution of freshwater ecosystems. Bull. Ecol. Soc. Amer. 45(4):157159.
Ragotzkie, R. A. and G. E. Likens. 1964. The heat balance of two Antarctic lakes. Limnol. Oceanogr.
9(3):412-425.
Likens, G. E. 1965. Measurement of background radiation in lakes. Ecology 46(4):544-548.
Likens, G. E. and R. A. Ragotzkie. 1965. Vertical water motions in a small ice-covered lake. J.
Geophys. Res. 70(10):2333-2344.
Likens, G. E. and P. L. Johnson. 1966. A chemically stratified lake in Alaska. Science 153(3738):875877.
Likens, G. E. and R. A. Ragotzkie. 1966. Rotary circulation of water in an ice-covered lake. Verh.
Internat. Verein. Limnol. 16(1):126-133.
Bormann, F. H. and G. E. Likens. 1967. Nutrient cycling. Science 155(3761):424-429.
Johnson, N. M. and G. E. Likens. 1967. A steady-state thermal gradient in the sediments of ameromictic lake. J. Geophys. Res. 72(12):3049-3052.
Likens, G. E. 1967. Some chemical characteristics of meromictic lakes in North America. pp. 17-62.
In: D. Jackson (ed.). Some Aspects of Meromixis. Syracuse University, Syracuse, New York.
Likens, G. E., F. H. Bormann, N. M. Johnson and R. S. Pierce. 1967. The calcium, magnesium,
potassium, and sodium budgets for a small forested ecosystem. Ecology 48(5):772-785.
Bormann, F. H., G. E. Likens, D. W. Fisher and R. S. Pierce. 1968. Nutrient loss accelerated by clearcutting of a forest ecosystem. pp. 187-195. In: Symposium on Primary Productivity and Mineral
Cycling in Natural Ecosystems. University of Maine Press, Orono; Also in Science 159(3817):882-884.
Fisher, D. W., A. W. Gambell, G. E. Likens and F. H. Bormann. 1968. Atmospheric contributions towater quality of streams in the Hubbard Brook Experimental Forest, New Hampshire. Water Resour.
Res. 4(5):1115-1126.
Johnson, N. M., G. E. Likens, F. H. Bormann and R. S. Pierce. 1968. Rate of chemical weathering ofsilicate minerals in New Hampshire. Geochim. Cosmochim. Acta 32:531-545.
Kilham, P. and G. E. Likens. 1968. Penetration of light in the lakes of Grafton County, New
Hampshire. N.H. Department of Resources and Economic Development, Concord, New Hampshire. 93
pp.
Likens, G. E. 1968. Limnology – recent studies on meromictic lakes. pp. 232-233. In: McGraw-Hill
Yearbook of Science and Technology. McGraw-Hill Book Co., New York.
Likens, G. E. and P. L. Johnson. 1968. A limnological reconnaissance in interior Alaska. U.S. Army
Cold Regions Research and Engineering Laboratory, Hanover, N.H., Research Report 239. 45 pp.
Smith, W. H., F. H. Bormann and G. E. Likens. 1968. Response of chemoautotrophic nitrifiers to forest
cutting. Soil Science 106(6):471-473.
Bormann, F. H. and G. E. Likens. 1969. A watershed approach to problems of nutrient cycling in forest
ecosystems. pp. 2303-2306. In: Proc. 6th World Forestry Congress, Vol. 2, Tech. Comm. III. Madrid,
Spain.
Bormann, F. H. and G. E. Likens. 1969. The watershed-ecosystem concept and studies of nutrient
cycles. pp. 49-76. In: G. VanDyne (ed.). The Ecosystem Concept in Natural Resource Management,
Chap. IV. Academic Press, New York.
Bormann, F. H., G. E. Likens and J. S. Eaton. 1969. Biotic regulation of particulate and solution losses
from a forest ecosystem. BioScience 19(7):600-610.
Collins, L. W. and G. E. Likens. 1969. The effect of altitude on the distribution of aquatic plants insome lakes of New Hampshire, USA. Verh. Internat. Verein. Limnol. 17:154-172.
Eaton, J. S., G. E. Likens and F. H. Bormann. 1969. Use of membrane filters in gravimetric analyses ofparticulate matter in natural waters. Water Resour. Res. 5(5):1151-1156.
Johnson, N. M., G. E. Likens, F. H. Bormann, D. W. Fisher and R. S. Pierce. 1969. A working modelfor the variation in stream water chemistry at the Hubbard Brook Experimental Forest, New Hampshire.
Water Resour. Res. 5(6):1353-1363.

97

28.
29.
30.

31.
32.
33.
34.
35.

36.
37.
38.

39.
40.
41.
42.
43.
44.

45.
46.
47.
48.

49.

50.
51.

98

Likens, G. E., F. H. Bormann and N. M. Johnson. 1969. Nitrification: importance to nutrient losses
from a cutover forested ecosystem. Science 163(3872):1205-1206.
Likens, G. E. and N. M. Johnson. 1969. Measurement and analysis of the annual heat budget for the
sediments in two Wisconsin lakes. Limnol. Oceanogr. 14(1):115-135.
Likens, G. E. and P. L. Johnson. 1969. Measurements of background radiation in aquatic habitats in
Alaska. pp. 319-328. In: D. J. Nelson and F. C. Evans (eds.). Proc. 2nd National Symposium onRadioecology. Ann Arbor, Michigan.
McConnochie, K. and G. E. Likens. 1969. Some trichoptera of the Hubbard Brook Experimental Forest
in central New Hampshire. Can. Field Nat. 83(2):147-154.
Bormann, F. H. and G. E. Likens. 1970. The nutrient cycles of an ecosystem. Sci. Amer. 223(4):92101.
Bormann, F. H., T. G. Siccama, G. E. Likens and R. H. Whittaker. 1970. The Hubbard Brook
Ecosystem Study: composition and dynamics of the tree stratum. Ecol. Monogr. 40(4):373-388.
Likens, G. E. and F. H. Bormann. 1970. Chemical analyses of plant tissues from the Hubbard Brookecosystem in New Hampshire. Yale University School of Forestry Bulletin 79. 25 pp.
Likens, G. E., F. H. Bormann, N. M. Johnson, D. W. Fisher and R. S. Pierce. 1970. Effects of forest
cutting and herbicide treatment on nutrient budgets in the Hubbard Brook watershed-ecosystem. Ecol.
Monogr. 40(1):23-47.
Likens, G. E. and J. S. Eaton. 1970. A polyurethane stemflow collector for trees and shrubs. Ecology
51(5):938-939.
Likens, G. E. and J. J. Gilbert. 1970. Notes on quantitative sampling of natural populations ofplanktonic rotifers. Limnol. Oceanogr. 15(5):816-820.
Pierce, R. S., J. W. Hornbeck, G. E. Likens and F. H. Bormann. 1970. Effect of elimination ofvegetation on stream water quantity and quality. pp. 311-328. In: International Symposium on the
Results of Research on Representative and Experimental Basins. Wellington, New Zealand. Internat.
Assoc. Sci. Hydrol.
Siccama, T. G., F. H. Bormann and G. E. Likens. 1970. The Hubbard Brook Ecosystem Study:
productivity, nutrients, and phytosociology of the herbaceous layer. Ecol. Monogr. 40(4):389-402.
Bormann, F. H. and G. E. Likens. 1971. The ecosystem concept and the rational management of natural
resources. Yale Sci. Mag. 45(7):2-8.
Bowers, R., P. Hohenberg, G. E. Likens, W. Lynn, D. Nelkin and M. Nelkin. 1971. A program tocoordinate environmental research. Amer. Sci. 59(2):183-187.
Likens, G. E. 1971. Lake, meromictic. pp. 435-437. In: McGraw-Hill Encyclopedia of Science andTechnology, Vol. 7. McGraw-Hill Book Co., New York.
Likens, G. E., A. F. Bartsch, G. H. Lauff and J. E. Hobbie. 1971. Nutrients and eutrophication. Science
172(3985):873-874.
Likens, G. E., F. H. Bormann, R. S. Pierce and D. W. Fisher. 1971. Nutrient-hydrologic cycle
interaction in small forested watershed-ecosystems. pp. 553-563. In: P. Duvigneaud (ed.). Proc.
Brussels Symposium on Productivity of Forest Ecosystems, 1969. UNESCO, Paris.
Fisher, S. G. and G. E. Likens. 1972. Stream ecosystem: organic energy budget. BioScience 22(1):3335.
Gosz, J. R., G. E. Likens and F. H. Bormann. 1972. Nutrient content of litterfall on the Hubbard Brook
Experimental Forest, New Hampshire. Ecology 53(5):769-784.
Johnson, N. M., R. C. Reynolds and G. E. Likens. 1972. Atmospheric sulfur: its effect on the chemical
weathering of New England. Science 177(4048):514-516.
Likens. G. E. 1972. Effects of deforestation on water quality. pp. 133-140. In: Proc. American Societyof Civil Engineers Symposium on the Interdisciplinary Aspects of Watershed Management, 1970.
Bozeman, Montana.
Likens, G. E. 1972. Eutrophication and aquatic ecosystems. pp. 3-13. In: G. E. Likens (ed.). Nutrientsand Eutrophication. Proc. American Society of Limnology and Oceanography Special Symposia, Vol.
1. Lawrence, Kansas.
Likens, G. E. 1972. Mirror Lake: its past, present and future? Appalachia 39(2):23-41.
Likens, G. E. 1972. The chemistry of precipitation in the central Finger Lakes Region. Water

52.
53.
54.
55.

56.
57.
58.
59.
60.
61.
62.

63.
64.
65.

66.
67.

68.

69.
70.
71.

72.
73.
74.
75.

Resources and Marine Sciences Center Tech. Report 50. Cornell University, Ithaca, New York. 47 pp.
+ 14 figs.
Likens, G. E. and F. H. Bormann. 1972. Biogeochemical cycles. The Science Teacher 39(4):15-20.
Likens, G. E. and F. H. Bormann. 1972. Nutrient cycling in ecosystems. pp. 25-67. In: J. Wiens (ed.).
Ecosystem Structure and Function. Oregon State University Press, Corvallis.
Likens, G. E., F. H. Bormann and N. M. Johnson. 1972. Acid rain. Environment 14(2):33-40.
Pierce, R. S., C. W. Martin, C. C. Reeves, G. E. Likens and F. H. Bormann. 1972. Nutrient loss fromclearcuttings in New Hampshire. pp. 285-295. In: Symposium on Watersheds in Transition. Fort
Collins, Colorado. American Water Resources Association and Colorado State University.
Burton, T. M. and G. E. Likens. 1973. The effect of strip-cutting on stream temperatures in the
Hubbard Brook Experimental Forest, New Hampshire. BioScience 23(7):433-435.
Eaton, J. S., G. E. Likens and F. H. Bormann. 1973. Throughfall and stemflow chemistry in a northernhardwood forest. J. Ecol. 61(2):495-508.
Fisher, S. G. and G. E. Likens. 1973. Energy flow in Bear Brook, New Hampshire: an integrative
approach to stream ecosystem metabolism. Ecol. Monogr. 43(4):421-439.
Gosz, J. R., G. E. Likens and F. H. Bormann. 1973. Nutrient release from decomposing leaf and branchlitter in the Hubbard Brook forest, New Hampshire. Ecol. Monogr. 43(2):173-191.
Hobbie, J. E. and G. E. Likens. 1973. The output of phosphorus, dissolved organic carbon and fineparticulate carbon from Hubbard Brook watersheds. Limnol. Oceanogr. 18(5):734-742.
Likens, G. E. 1973. Primary production: freshwater ecosystems. Human Ecol. 1(4):347-356.
Whittaker, R. H. and G. E. Likens. 1973. Carbon in the biota. pp. 281-302. In: G. M. Woodwell and E.
V. Pecan (eds.). Carbon and the Biosphere. U.S. Atomic Energy Commission, CONF-720510,
Springfield, Virginia.
Whittaker, R. H. and G. E. Likens. 1973. Introduction (the primary production of the biosphere).
Human Ecol. 1(4):301-302.
Whittaker, R. H. and G. E. Likens. 1973. Primary production: the biosphere and man. Human Ecol.
1(4):357-369.
Bormann, F. H., G. E. Likens, T. G. Siccama, R. S. Pierce and J. S. Eaton. 1974. The export ofnutrients and recovery of stable conditions following deforestation at Hubbard Brook. Ecol. Monogr.
44(3):255-277.
Cogbill, C. V. and G. E. Likens. 1974. Acid precipitation in the northeastern United States. Water
Resour. Res. 10(6):1133-1137.
Hornbeck, J. W. and G. E. Likens. 1974. The ecosystem concept for determining the importance ofchemical composition of snow. pp. 139-151. In: Advanced Concepts of Techniques in the Study ofSnow and Ice Resources. ISBN 0-309-02235-5. National Academy of Sciences, Washington, DC; Also,
31st Annual Eastern Snow Conference Proc., pp. 145-155.
Likens, G. E. 1974. The runoff of water and nutrients from watersheds tributary to Cayuga Lake, New
York. Water Resources and Marine Sciences Center Publ. 81. Cornell University, Ithaca, New York.
124 pp.
Likens, G. E. 1974. Water and nutrient budgets for Cayuga Lake, New York. Water Resources andMarine Sciences Center Publ. 82. Cornell University, Ithaca, New York. 91 pp.
Likens, G. E. and F. H. Bormann. 1974. Acid rain: a serious regional environmental problem. Science
184(4142):1176-1179.
Likens, G. E. and F. H. Bormann. 1974. Effects of forest clearing on the northern hardwood forest
ecosystem and its biogeochemistry. pp. 330-335. In: Proc. First Internat. Congr. of Ecology,
September 1974. Centre Agric. Publ. Doc. Wageningen, The Hague, The Netherlands.
Likens, G. E. and F. H. Bormann. 1974. Linkages between terrestrial and aquatic ecosystems.
BioScience 24(8):447-456.
Sturges, F. W., R. T. Holmes and G. E. Likens. 1974. The role of birds in nutrient cycling in a northernhardwoods ecosystem. Ecology 55(1):149-155.
Whittaker, R. H., F. H. Bormann, G. E. Likens and T. G. Siccama. 1974. The Hubbard Brook
Ecosystem Study: forest biomass and production. Ecol. Monogr. 44(2):233-254.
Burton, T. M. and G. E. Likens. 1975. Energy flow and nutrient cycling in salamander populations in

99

76.
77.
78.

79.

80.

81.
82.
83.
84.

85.

86.

87.

88.
89.
90.
91.
92.

93.

94.
95.
96.

100

the Hubbard Brook Experimental Forest, New Hampshire. Ecology 56(5):1068-1080.
Burton, T. M. and G. E. Likens. 1975. Salamander populations and biomass in the Hubbard Brook
Experimental Forest, New Hampshire. Copeia 3:541-546.
Gerhart, D. Z. and G. E. Likens. 1975. Enrichment experiments for determining nutrient limitation:
four methods compared. Limnol. Oceanogr. 20(4):649-653.
Gosz, J. R., G. E. Likens, J. S. Eaton and F. H. Bormann. 1975. Leaching of nutrients from leaves of
selected tree species in New Hampshire. pp. 630-641. In: F. G. Howell, J. B. Gentry and M. H. Smith(eds.). Mineral Cycling in Southeastern Ecosystems. ERDA Symp. Series CONF-740513. Augusta,
Georgia; May 1974.
Hornbeck, J. W., G. E. Likens, R. S. Pierce and F. H. Bormann. 1975. Strip cutting as a means ofprotecting site and streamflow quality when clearcutting northern hardwoods. pp. 209-229. In: B.
Bernier and C. H. Winget (eds.). Proc. 4th N. Amer. Forest Soils Conference on Forest Soils and Forest
Land Management, August 1973, Quebec, Canada.
Hornbeck, J. W., R. S. Pierce, G. E. Likens and C. W. Martin. 1975. Moderating the impact ofcontemporary forest cutting on hydrologic and nutrient cycles. pp. 423-433. In: Proc. of Internat. Symp.
On Hydrologic Sciences. Publ. 117. Tokyo, Japan.
Jordan, M. J. and G. E. Likens. 1975. An organic carbon budget for an oligotrophic lake in New
Hampshire, USA. Verh. Internat. Verein. Limnol. 19(2):994-1003.
Lehman, J. T., D. B. Botkin and G. E. Likens. 1975. The assumptions and rationales of a computermodel of phytoplankton population dynamics. Limnol. Oceanogr. 20(3):343-364.
Lehman, J. T., D. B. Botkin and G. E. Likens. 1975. Lake eutrophication and the limiting CO2 concept:
a simulation study. Verh. Internat. Verein. Limnol. 19(2):300-304.
Likens, G. E. 1975. Acid precipitation: our understanding of the phenomenon. pp. 45-75. In: Proc. ofa Conference on Emerging Environmental Problems. May 1975, Rensselaerville, New York. EPA902/9-75-001.
Likens, G. E. 1975. Nutrient flux and cycling in freshwater ecosystems. pp. 314-348. In: F. G.
Howell, J. B. Gentry and M. H. Smith (eds.). Mineral Cycling in Southeastern Ecosystems. ERDA
Symp. Series CONF-740513. May 1974, Augusta, Georgia.
Likens, G. E. 1975. Primary production and inland aquatic ecosystems. Chapter 9, pp. 185-202. In: H.
Lieth and R. H. Whittaker (eds.). Primary Productivity of the Biosphere. Springer-Verlag New YorkInc.
Likens, G. E. and F. H. Bormann. 1975. An experimental approach in New England landscapes. pp. 729. In: A. D. Hasler (ed.). Proc. INTECOL Symp. On Coupling of Land and Water Systems, 1971.
Leningrad. Springer-Verlag New York Inc.
Likens, G. E. and F. H. Bormann. 1975. Acidity in rainwater: Has an explanation been provided?
Science 188:957-958.
Likens, G. E. and M. B. Davis. 1975. Post-glacial history of Mirror Lake and its watershed in New
Hampshire, USA: an initial report. Verh. Internat. Verein. Limnol. 19(2):982-993.
Makarewicz, J. C. and G. E. Likens. 1975. Niche analysis of a zooplankton community. Science
190:1000-1003.
Walker, K. F. and G. E. Likens. 1975. Meromixis and a reconsidered typology of lake circulation
patterns. Verh. Internat. Verein. Limnol. 19(2):442-458.
Whittaker, R. H. and G. E. Likens. 1975. The biosphere and man. Chapter 15, pp. 305-328. In: H.
Lieth and R. H. Whittaker (eds.). Primary Productivity of the Biosphere. Springer-Verlag New YorkInc.
Whittaker, R. H., G. E. Likens and H. Lieth. 1975. Scope and purpose of this volume. Chapter 1, pp.
3-5. In: H. Lieth and R. H. Whittaker (eds.). Primary Productivity of the Biosphere. Springer-Verlag
New York Inc.
Vlijm, L. and G. E. Likens. 1975. Discussion. pp. 232-236. In: W. H. van Dobben and R. H. LoweMcConnel (eds.). Unifying Concepts in Ecology. Dr. W. Junk B.V. Publishers, The Hague.
Cogbill, C. V. and G. E. Likens. 1976. Reply to Comment on ‘Acid precipitation in the northeastern
United States.’ Water Resour. Res. 12(3):571.
Galloway, J. N. and G. E. Likens. 1976. Calibration of collection procedures for determination of

97.
98.

99.

100.

101.
102.

103.
104.
105.

106.
107.
108.

109.

110.

111.

112.
113.

precipitation chemistry. pp. 137-156. In: L. S. Dochinger and T. A. Seliga (eds.). Proc. The FirstInternat. Symp. on Acid Precipitation and the Forest Ecosystem. USDA Tech. Report NE-23; Also,
Water, Air, and Soil Pollut. 6:241-258 (1976).
Galloway, J. N., G. E. Likens and E. S. Edgerton. 1976. Acid precipitation in the northeastern UnitedStates: pH and acidity. Science 194:722-724.
Galloway, J. N., G. E. Likens and E. S. Edgerton. 1976. Hydrogen ion speciation in the acidprecipitation of the northeastern United States. pp. 383-396. In: L. S. Dochinger and T. A. Seliga (eds.).
Proc. The First Internat. Symp. on Acid Precipitation and the Forest Ecosystem. USDA Tech. Report
NE-23; Also, Water, Air, and Soil Pollut. 6:423-433 (1976).
Gosz, J. R., G. E. Likens and F. H. Bormann. 1976. Organic matter and nutrient dynamics of the forest
floor in the Hubbard Brook forest. Oecologia (Berl.) 22:305-320. Springer-Verlag New York Inc.;
Also, pp. 311-319. In: J. K. Marshall (eds.). The Belowground Ecosystem: A Synthesis of Plant
Associated Processes. Science Series No. 26, Ft. Collins, Colorado (1977).
Hornbeck, J. W., G. E. Likens and J. S. Eaton. 1976. Seasonal patterns in acidity of precipitation andthe implications for forest-stream ecosystems. pp. 597-609. In: L. S. Dochinger and T. A. Seliga (eds.).
Proc. The First Internat. Symp. on Acid Precipitation and the Forest Ecosystem. USDA Forest Service
General Tech. Report NE-23; Also, Water, Air, and Soil Pollution 7:355-365 (1977).
Likens, G. E. 1976. Acid precipitation. Chemical and Engineering News 54:29-44.
Likens, G. E., F. H. Bormann, J. S. Eaton, R. S. Pierce and N. M. Johnson. 1976. Hydrogen ion input tothe Hubbard Brook Experimental Forest, New Hampshire during the last decade. pp. 397-407. In: L. S.
Dochinger and T. A. Seliga (eds.). Proc. The First Internat. Symp. on Acid Precipitation and the Forest
Ecosystem. USDA Forest Serv. General Tech. Report NE-23; Also, Water, Air, and Soil Pollution
6:435-445 (1976).
Likens, G. E., N. M. Johnson, J. N. Galloway and F. H. Bormann. 1976. Acid precipitation: strong andweak acids. Science 194:643-645.
Likens, G. E. and R. S. Pierce. 1976. Effects on aquatic systems. pp. 8-10. In: Workshop Report on
Acid Precipitation and the Forest Ecosystem. USDA Forest Service General Tech. Report NE-26.
Miller, J. M., J. N. Galloway and G. E. Likens. 1976. The use of ARL trajectories for the evaluation of
precipitation chemistry data. pp. 131-132. In: L. S. Dochinger and T. A. Seliga (eds.). Proc. The FirstInternat. Symp. on Acid Precipitation and the Forest Ecosystem. USDA Forest Service General Tech.
Report NE-23.
Bormann, F. H. and G. E. Likens. 1977. The fresh air - clean water exchange. Natural History
86(9):62-71; Also, Environment 79/80:198-200 (1979).
Bormann, F. H., G. E. Likens and J. Melillo. 1977. Nitrogen budget for an aggrading northernhardwood forest ecosystem. Science 196(4293):981-983.
Delwiche, C. C. and G. E. Likens. 1977. Biological response to fossil fuel combustion products. pp.
73-88. In: W. Stumm (ed.). Global Chemical Cycles and Their Alterations by Man. Dahlem
Konferenzen, Berlin.
Lerman, A. (Rapporteur), M. Bernhard, B. Bolin, C. C. Delwiche, D. H. Ehhart, S. P. Gessel, D. R.
Kester, W. E. Krumbein, G. E. Likens, F. T. Mackenzie, W. A. Reiners, W. Stumm, G. M. Woodwell
and P. J. Zinke. 1977. Fossil fuel burning: its effects on the biosphere and biogeochemical cycles.
Group Report. pp. 275-289. In: W. Stumm (eds.). Global Chemical Cycles and Their Alterations byMan. Dahlem Konferenzen, Berlin.
Likens, G. E. 1977. Precipitation sampling techniques. pp. 334-339. In: J. Prospero (ed.).
Background Papers for A Workshop on the Tropospheric Transport of Pollutants to the Ocean. Miami,
Florida. December 1975.
Likens, G. E., J. S. Eaton and J. S. Galloway. 1977. Precipitation as a source of nutrients for terrestrial
and aquatic ecosystems. pp. 552-570. In: R. G. Semonin and R. W. Beadle (Coordinators). ERDA
Symp. Series 41, Precipitation Scavenging (1974). Champaign, Illinois. CONF-741003.
Likens, G. E. and G. R. Hendrey. 1977. Acid precipitation (letter response). Chemical and Engineering
News 55(25):60-61.
Eaton, J. S., G. E. Likens and F. H. Bormann. 1978. The input of gaseous and particulate sulfur to aforest ecosystem. Tellus 30:546-551.

101114. Galloway, J. N. and G. E. Likens. 1978. The collection of precipitation for chemical analysis. Tellus
30:71-82.
115. Glass, N. R., G. E. Likens and L. S. Dochinger. 1978. The ecological effects of atmospheric deposition.
pp. 113-119. In: EPA, ORD Decision Series, Energy/Environment III. EPA-600/9-78-022.
116. Gosz, J. R., R. T. Holmes, G. E. Likens and F. H. Bormann. 1978. The flow of energy in a forest
ecosystem. Sci. Amer. 238(3):92-102.
117. Likens, G. E. 1978. Precipitation (meteorology). pp. 303-305. In: McGraw-Hill Yearbook of Scienceand Technology, McGraw-Hill Book Co., New York.
118. Likens, G. E., F. H. Bormann, R. S. Pierce and W. A. Reiners. 1978. Recovery of a deforested
ecosystem. Science 199(4328):492-496.
119. Likens, G. E. and O. L. Loucks. 1978. Analysis of five North American lake ecosystems. III. Sources,
loading and fate of nitrogen and phosphorus. Verh. Internat. Verein. Limnol. 20:568-573.
120. Makarewicz, J. C. and G. E. Likens. 1978. Zooplankton niches and the community structure
controversy. Science 200(4340):458-463.
121. Miller, J. M., J. N. Galloway and G. E. Likens. 1978. Origin of air masses producing acid precipitation
at Ithaca, New York: A Preliminary Report. Geophys. Res. Letters 5(9):757-760.
122. Moeller, R. E. and G. E. Likens. 1978. Seston sedimentation in Mirror Lake, New Hampshire, and its
relationship to long-term sediment accumulation. Verh. Internat. Verein. Limnol. 20:525-530.
123. Richey, J. E., R. C. Wissmar, A. H. Devol, G. E. Likens, J. S. Eaton, R. G. Wetzel, W. E. Odum, P. H.
Rich, O. L. Loucks, R. T. Prentki and N. M. Johnson. 1978. Carbon flux in four lake ecosystems: a
structural approach. Science 202(4373):1183-1186.
124. Woodwell, G. M., R. H. Whittaker, W. A. Reiners, G. E. Likens, C. C. Delwiche and D. B. Botkin.
1978. The biota and the world carbon budget. Science 199(4325):141-146.
125. Bilby, R. E. and G. E. Likens. 1979. Effect of hydrologic fluctuations on the transport of fineparticulate organic carbon in a small stream. Limnol. Oceanogr. 24(1):69-75.
126. Bormann, F. H. and G. E. Likens. 1979. Catastrophic disturbance and the steady state in northernhardwood forests. Amer. Sci. 67(6):660-669.
127. Cole, J. J. and G. E. Likens. 1979. Measurements of mineralization of phytoplankton detritus in an
oligotrophic lake. Limnol. Oceanogr. 24(3):541-547.
128. Galloway, J. N. and G. E. Likens. 1979. Atmospheric enhancement of metal deposition in Adirondacklake sediments. Limnol. Oceanogr. 24(3):427-433.
129. Galloway, J. N., B. J. Cosby, Jr. and G. E. Likens. 1979. Acid precipitation: measurement of pH andacidity. Limnol. Oceanogr. 24(6):1161-1165.
130. Likens, G. E. 1979. Session IX: Summing up and recommendations. p. 67. In: G. R. Hendrey (ed.).
Limnological Aspects of Acid Precipitation. Internat. Workshop at Sagamore Lake Conference Center,
September 1978. EPA, Corvallis and Brookhaven National Laboratory 51074.
131. Likens, G. E. and F. H. Bormann. 1979. The role of watershed and airshed in lake metabolism. pp.
195-211. In: W. Rodhe, G. E. Likens and C. Serruya (eds.). Lake Metabolism and Management.
Papers Emanating from the Jubilee Symposium of Uppsala University, Sweden. Arch. Hydrobiol. Beih.
Ergebn. Limnol. 13.
132. Likens, G. E. and T. J. Butler. 1979. Trends in acid precipitation in the eastern U.S. pp. 104-108. In:
M. MacCracken (coordinator), The Multistate Atmospheric Power Production Pollution Study -MAP3S. Progress Report for FY1977 and FY1978. DOE/EV-0040.
133. Likens, G. E., R. F. Wright, J. N. Galloway and T. J. Butler. 1979. Acid rain. Sci. Amer. 241(4):43-51.
134. Makarewicz, J. C. and G. E. Likens. 1979. Structure and function of the zooplankton community of
Mirror Lake, New Hampshire. Ecol. Monogr. 49(1):109-127.
135. Meyer, J. L. and G. E. Likens. 1979. Transport and transformation of phosphorus in a forest stream
ecosystem. Ecology 60(6):1255-1269.
136. Whittaker, R. H., G. E. Likens, F. H. Bormann, J. S. Eaton and T. G. Siccama. 1979. The Hubbard
Brook Ecosystem Study: forest nutrient cycling and element behavior. Ecology 60(1):203-220.
137. Woodwell, G. M., R. H. Whittaker, W. A. Reiners, G. E. Likens, C. C. Delwiche and D. B. Botkin.
1979. Reply to ‘Where has all the carbon gone?’ by C. W. Ralston. Science 204:1354-1356.
138. Bilby, R. E. and G. E. Likens. 1980. Importance of organic debris dams in the structure and function of102

stream ecosystems. Ecology 61(5):1107-1113.
139. Eaton, J. S., G. E. Likens and F. H. Bormann. 1980. Wet and dry deposition of sulfur at Hubbard
Brook. pp. 69-75. In: T. C. Hutchinson and M. Havas (eds.). Effects of Acid Precipitation on
Terrestrial Ecosystems. NATO Conf. Series 1 : Ecology 4. Plenum Publishing Corp.
140. Hall, R. J. and G. E. Likens. 1980. Ecological effects of experimental acidification on a stream
ecosystem. pp. 375-376. In: D. Drabløs and A. Tollan (eds.). Ecological Impact of Acid Precipitation.
Proc. of Internat. Conf., Sandefjord, Norway. March 1980.
141. Hall, R. J. and G. E. Likens. 1980. Ecological effects of whole-stream acidification. pp. 443-451. In:
D. S. Shriner, C. R. Richmond and S. E. Lindberg (eds.). Atmospheric Sulfur Deposition -Environmental Impact and Health Effects. Proc. Second Life Sciences Symp., Gatlinburg, Tennessee.
October 1979.
142. Hall, R. J., G. E. Likens. S. B. Fiance and G. R. Hendrey. 1980. Experimental acidification of a stream
in the Hubbard Brook Experimental Forest, New Hampshire. Ecology 61(4):976-989.
143. Jordan, M. J. and G. E. Likens. 1980. Measurement of planktonic bacterial production in an
oligotrophic lake. Limnol. Oceanogr. 25(4):721-734.
144. Last, F. T., G. E. Likens, B. Ullrich and L. Walløe. 1980. Acid precipitation -- progress and problems.
Conference Summary. pp. 10-12. In: D. Drabløs and A. Tollan (eds.). Ecological Impact of Acid
Precipitation. Proc. of Internat. Conf., Sandefjord, Norway. March 1980.
145. Likens, G. E. 1980. The influence of reduced streamflows on water quality: a discussion. pp. 49-68.
In: W. O. Spofford, Jr., A. L. Parker and A. V. Kneese (eds.). Energy Development in the Southwest:
Problems of Water, Fish and Wildlife in the Upper Colorado River Basin, Vol. 2. Resources for the
Future, Washington, D.C.
146. Likens, G. E., F. H. Bormann and J. S. Eaton. 1980. Variations in precipitation and streamwaterchemistry at the Hubbard Brook Experimental Forest during 1964 to 1977. pp. 443-464. In: T. C.
Hutchinson and M. Havas (eds.). Effects of Acid Precipitation on Terrestrial Ecosystems. NATO
Conference Series 1 : Ecology 4. Plenum Publishing Corp.
147. Galloway, J. N. and G. E. Likens. 1981. Acid precipitation: the importance of nitric acid. Atmos.
Environ. 15(6):1081-1085.
148. Hall, R. J. and G. E. Likens. 1981. Chemical flux in an acid-stressed stream. Nature 292(5821):329331.
149. Johnson, N. M., C. T. Driscoll, J. S. Eaton, G. E. Likens and W. H. McDowell. 1981. “Acid rain,”dissolved aluminum and chemical weathering at the Hubbard Brook Experimental Forest, New
Hampshire. Geochim. Cosmoch. Acta 45(9):1421-1437.
150. Leonard, R. L., C. R. Goldman and G. E. Likens. 1981. Some measurements of the pH and chemistryof precipitation at Davis and Lake Tahoe, California. J. Water, Air, and Soil Pollution 15:153-167.
151. Likens, G. E. 1981. The not so gentle rain. pp. 212-227. In: Yearbook of Science and the Future.
Encyclopaedia Britannica.
152. Likens, G. E. and T. J. Butler. 1981. Recent acidification of precipitation in North America. Atmos.
Environ. 15(7):1103-1109.
153. Likens, G. E., F. H. Bormann and N. M. Johnson. 1981. Interactions between major biogeochemical
cycles in terrestrial ecosystems. pp. 93-112. In: G. E. Likens (ed.). Some Perspectives of the Major
Biogeochemical Cycles. SCOPE 17. John Wiley & Sons Ltd., Chichester.
154. Meyer, J. L., G. E. Likens and J. Sloane. 1981. Phosphorus, nitrogen, and organic carbon flux in a
headwater stream. Arch. Hydrobiol. 91(1):28-44.
155. Strayer, D. L., J. J. Cole, G. E. Likens and D. Buso. 1981. Biomass and annual production of the
freshwater mussel Elliptio complanata in an oligotrophic, softwater lake. Freshwat. Biol. 11:435-440.
156. Cole, J. J., G. E. Likens and D. L. Strayer. 1982. Photosynthetically produced dissolved organic carbon:
an important carbon source for planktonic bacteria. Limnol. Oceanogr. 27(6):1080-1090.
157. Driscoll, C. T. and G. E. Likens. 1982. Hydrogen ion budget of an aggrading forested ecosystem.
Tellus 34:283-292.
158. Galloway, J. N., G. E. Likens, W. C. Keene and J. M. Miller. 1982. The composition of precipitation inremote areas of the world. J. Geophys. Res. 87(11):8771-8786.
159. Hall, R. J., J. M. Pratt and G. E. Likens. 1982. Effects of experimental acidification on103macroinvertebrate drift diversity in a mountain stream. J. Water, Air, and Soil Pollut. 18:273-287.
160. Likens, G. E. 1982. Acid rain. The World Book Encyclopedia, World Book – Childcraft International,
Inc. Chicago, Illinois.
161. Likens, G. E. 1982. Meromictic lake. pp. 346-348. In: McGraw-Hill Book Co., Professional andReference Book Division, Encyclopedia of Science and Technology, 5th edition.
162. Likens, G. E. and R. E. Bilby. 1982. Development, maintenance and role of organic-debris dams in
New England streams. pp. 122-128. In: F. J. Swanson, R. J. Janda, T. Dunne and D. W. Swanston(eds.). Sediment Budgets and Routing in Forested Drainage Basins. USDA Forest Service General
Technical Report PNW-141.
163. Confer, J. L., T. Kaaret and G. E. Likens. 1983. Zooplankton diversity and biomass in recently
acidified lakes. Can. J. Fish. Aquat. Sci. 40(1):36-42.
164. Lazrus, A. L., P. L. Haagenson, G. L. Kok, B. J. Huebert, C. W. Kreitzberg, G. E. Likens, V. A.
Mohnen, W. E. Wilson and J. W. Winchester. 1983. Acidity in air and water in a case of warm frontal
precipitation. Atmos. Environ. 17(3):581-591.
165. Likens, G. E. 1983. A priority for ecological research. Bull. Ecol. Soc. Amer. 64(4):234-243.
166. Likens, G. E., E. S. Edgerton and J. N. Galloway. 1983. The composition and deposition of organiccarbon in precipitation. Tellus 35B:16-24.
167. Butler, T. J., C. V. Cogbill and G. E. Likens. 1984. Effect of climatology on precipitation chemistry.
Bull. Amer. Meteorol. Soc. 65(6):639-640.
168. Cogbill, C. V., G. E. Likens and T. J. Butler. 1984. Uncertainties in historical aspects of acidprecipitation: getting it straight. Atmos. Environ. 18(10):2261-2270.
169. Cole, J. J., G. E. Likens and J. E. Hobbie. 1984. Decomposition of planktonic algae in an oligotrophic
lake. Oikos 42:257-266.
170. Cole, J. J., W. H. McDowell and G. E. Likens. 1984. Sources and molecular weight of “dissolved”
organic carbon in an oligotrophic lake. Oikos 42:1-9.
171. Galloway, J. N., G. E. Likens and M. Hawley. 1984. Acid precipitation: natural versus anthropogenic
components. Science 226:829-831.
172. Hall, R. J. and G. E. Likens. 1984. Effect of discharge rate on biotic and abiotic chemical flux in anacidified stream. Can. J. Fish. Aquat. Sci. 41(8):1132-1138.
173. Havas, M., T. Hutchinson and G. E. Likens. 1984. Effect of low pH on sodium regulation in two
species of Daphnia. Can. J. Zool. 62(10):1965-1970.
174. Havas, M., T. Hutchinson and G. E. Likens. 1984. Red herrings in acid rain research. Environ. Sci.
Technol. 18(6):176A-186A.
175. Johnson, N. M., G. E. Likens, M. C. Feller and C. T. Driscoll. 1984. Technical comment on “Acid rainon acid soil: a new perspective.” Science 225:1424-1425.
176. Likens, G. E. 1984. Acid rain: the smokestack is the “smoking gun.” Garden 8(4):12-18.
177. Likens, G. E. 1984. Beyond the shoreline: a watershed-ecosystem approach. Verh. Internat. Verein.
Limnol. 22:1-22.
178. Likens, G. E. 1984. Response to ‘Maybe acid rain isn’t the villain.’ Fortune 110(3):11-12.
179. Likens, G. E. 1984. We must take prompt action now. The Wall Street Journal, 28 June 1984, page 28.
180. Likens, G. E., F. H. Bormann, R. S. Pierce, J. S. Eaton and R. E. Munn. 1984. Long-term trends inprecipitation chemistry at Hubbard Brook, New Hampshire. Atmos. Environ. 18(12):2641-2647.
181. Munn, R. E., G. E. Likens, B. Weisman, J. W. Hornbeck, C. W. Martin and F. H. Bormann. 1984. A
meteorological analysis of the precipitation chemistry event samples at Hubbard Brook, New
Hampshire. Atmos. Environ. 18(12):2775-2779.
182. Bormann, F. H. and G. E. Likens. 1985. Air and watershed management and the aquatic ecosystem.
pp. 436-444. In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its
Environment. Springer-Verlag New York Inc.
183. Bormann, R. E., F. H. Bormann and G. E. Likens. 1985. Catastrophic disturbance and regional landuse. pp. 65-72. In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its
Environment. Springer-Verlag New York Inc.
184. Davis, M. B., R. E. Moeller, G. E. Likens, J. Ford, J. Sherman and C. Goulden. 1985. Paleoecology of
Mirror Lake and its watershed. pp. 410-429. In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic104

Ecology: Mirror Lake and its Environment. Springer-Verlag New York Inc.
185. deNoyelles, F. and G. E. Likens. 1985. Phytoplankton. pp. 161-175 and pp. 250-257. In: G. E. Likens(ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag
New York Inc.
186. Driscoll, C. T., J. N. Galloway, J. F. Hornig, G. E. Likens, M. Oppenheimer, K. A. Rahn and D. W.
Schindler. 1985. Is there scientific consensus on acid rain? Excerpts from six governmental reports.
Special Publication of the Institute of Ecosystem Studies, Millbrook, New York. 13 pp.
187. Hall, R. J. and G. E. Likens. 1985. Experimental acidification of a stream tributary to Hubbard Brook.
EPA Environmental Research Brief, EPA/600/M-85/011. 6 pp.
188. Hall, R. J., C. T. Driscoll, G. E. Likens and J. M. Pratt. 1985. Physical, chemical and biologicalconsequences of episodic aluminum additions to a stream. Limnol. Oceanogr. 30(1):212-220.
189. Havas, M. and G. E. Likens. 1985. Toxicity of aluminum and hydrogen ions to Daphnia catawba,
Holopedium gibberum, Chaoborus punctipennis and Chironomus anthracinus from Mirror Lake, New
Hampshire. Can. J. Zool. 63:1114-1119.
190. Havas, M. and G. E. Likens. 1985. Changes in 22Na influx and outflux in Daphnia magna (Straus) as afunction of elevated Al concentrations in soft water at low pH (acidic deposition). Proc. National
Academy of Sciences USA 82:7345-4349.
191. Havas, M., T. Hutchinson and G. E. Likens. 1985. Acid rain research. Environ. Sci. Technol. 19(1):20,
26.
192. Havas, M., T. C. Hutchinson and G. E. Likens. 1985. Comment on ‘Red herrings in acid rain research.’[Reply]. Environ. Sci. Technol. 19(7):646-648.
193. Johnson, N. M., G. E. Likens and J. S. Eaton. 1985. Stability, circulation and energy flux in Mirror
Lake. pp. 108-127. In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lakeand its Environment. Springer-Verlag New York Inc.
194. Jordan, M. J., G. E. Likens and B. J. Peterson. 1985. Organic carbon budget. pp. 292-301. In: G. E.
Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. SpringerVerlag New York Inc.
195. Likens, G. E. 1985. The aquatic ecosystem and air-land-water interactions. pp. 430-435. In: G. E.
Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. SpringerVerlag New York Inc.
196. Likens, G. E. 1985. An experimental approach for the study of ecosystems. J. Ecology 73(2):381-396.
197. Likens, G. E. 1985. The lake ecosystem. pp. 337-344. In: G. E. Likens (ed.). An Ecosystem Approachto Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag New York Inc.
198. Likens, G. E. 1985. Mirror Lake: cultural history. pp. 72-83. In: G. E. Likens (ed.). An Ecosystem
Approach to Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag New York Inc.
199. Likens, G. E. and F. H. Bormann. 1985. An ecosystem approach. pp. 1-8. In: G. E. Likens (ed.). An
Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag New YorkInc.
200. Likens, G. E. and R. E. Moeller. 1985. Chemistry. pp. 392-410. In: G. E. Likens (ed.). An Ecosystem
Approach to Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag New York Inc.
201. Likens, G. E. and R. E. Moeller. 1985. Fossil pigments. pp. 387-391. In: G. E. Likens (ed.). An
Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag New YorkInc.
202. Likens, G. E., J. S. Eaton and N. M. Johnson. 1985. Physical and chemical environment. pp. 89-108.
In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment.
Springer-Verlag New York Inc.
203. Likens, G. E., B. J. Peterson and J. J. Cole. 1985. Periphyton. pp. 175-177. In: G. E. Likens (ed.). An
Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. Springer-Verlag New YorkInc.
204. Likens, G. E., F. H. Bormann, R. S. Pierce and J. S. Eaton. 1985. The Hubbard Brook Valley. pp. 9-39.
In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment.
Springer-Verlag New York Inc.
205. Likens, G. E., J. S. Eaton, N. M. Johnson and R. S. Pierce. 1985. Flux and balance of water and

105

206.

207.
208.
209.

210.
211.
212.

213.
214.
215.

216.
217.
218.
219.

220.

221.
222.

223.
224.

225.
226.

106

chemicals. pp. 135-155. In: G. E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror
Lake and its Environment. Springer-Verlag New York Inc.
Makarewicz, J. C., G. E. Likens and M. J. Jordan. 1985. The pelagic region. pp. 322-337. In: G. E.
Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and its Environment. SpringerVerlag New York Inc.
Mitterer, R. H. and G. E. Likens. 1985. Biogeochemistry. In: McGraw-Hill Encyclopedia of Scienceand Technology, 6th edition.
Oppenheimer, M., J. N. Galloway, G. E. Likens and S. A. Norton. 1985. Acid deposition. Science
227(4691):1154-1156.
Prospero, J. M., W. C. Keene, J. N. Galloway, R. J. Delmas, L. Granat, G. Gravenhorst and G. E.
Likens. 1985. The deposition of sulfur and nitrogen from the remote atmosphere working-group report.
pp. 177-200. In: J. N. Galloway, R. J. Charlson, M. O. Andreae and H. Rodhe (eds.). The
Biogeochemical Cycling of Sulfur and Nitrogen in the Remote Atmosphere. Bermuda Biological Station,
Bermuda. D. Reidel Publishing Company.
Richey, J. S., W. H. McDowell and G. E. Likens. 1985. Nitrogen transformation in a small mountainstream. Hydrobiologia 124(2):129-139.
Galloway, J. N. and G. E. Likens. 1986. The composition of precipitation in remote areas of the world.
Atmos. Environ. & Acid Rain (China) 1(2):34-39.
Hornbeck, J. W., C. W. Martin, R. S. Pierce, F. H. Bormann, G. E. Likens and J. S. Eaton. 1986.
Clearcutting northern hardwoods: effects on hydrologic and nutrient ion budgets. Forest Science32(3):667-686.
Likens, G. E. 1986. Acid rain: causes, consequences and correctives. Atmos. Environ. & Acid Rain
(China) 1(1):33-40.
Likens, G. E. 1986. Future of ecosystem studies. Bull. Ecol. Soc. Amer. 67(3):257-258.
Martin, C. W., R. S. Pierce, G. E. Likens and F. H. Bormann. 1986. Clearcutting affects stream
chemistry in the White Mountains of New Hampshire. USDA Forest Service Research Paper NE-579.
12 pp.
Nodvin, S. C., C. T. Driscoll and G. E. Likens. 1986. The effect of pH on sulfate adsorption by a forest
soil. Soil Science 142(2):69-75.
Nodvin, S. C., C. T. Driscoll and G. E. Likens. 1986. Simple partitioning of anions and dissolved
organic carbon in a forest soil. Soil Science 142(1):27-35.
Strayer, D. L. and G. E. Likens. 1986. An energy budget for the zoobenthos of Mirror Lake, New
Hampshire. Ecology 67(2):303-313.
Strayer, D. L., J. S. Glitzenstein, C. Jones, J. Kolasa, G. E. Likens, M. McDonnell, G. G. Parker and
S.T.A. Pickett. 1986. Long-term ecological studies: An illustrated account of their design, operation,and importance to ecology. Occasional Publication of the Institute of Ecosystem Studies, No. 2.
Millbrook, New York. 38 pp.
Weathers, K. C., G. E. Likens, F. H. Bormann, J. S. Eaton, W. B. Bowden, J. Andersen, D.A. Cass, J. N.
Galloway, W. C. Keene, K. D. Kimball, P. Huth and D. Smiley. 1986. A regional acidic cloud/fog
water event in the eastern United States. Nature 319:657-659.
Bormann, F. H. and G. E. Likens. 1987. Changing perspectives on air-pollution stress. BioScience37(6):370.
Bormann, F. H., W. B. Bowden, R. S. Pierce, S. P. Hamburg, G. K. Voigt, R. C. Ingersoll and G. E.
Likens. 1987. The Hubbard Brook sandbox experiment. pp. 215-256. In: W. R. Jordan, M. E. Gilpin
and J. D. Aber (eds.). Restoration Ecology. Cambridge University Press.
Galloway, J. N., Zhao Dianwu, Xiong Jiling and G. E. Likens. 1987. Acid rain: a comparison of China,
United States and a remote area. Science 236:1559-1562.
Hall, R. J., C. T. Driscoll and G. E. Likens. 1987. Importance of hydrogen ions and aluminium inregulating the structure and function of stream ecosystems: an experimental test. Freshwater Biology
18:17-43.
Hedin, L. O., G. E. Likens and F. H. Bormann. 1987. Decrease in precipitation acidity resulting fromdecreased SO42- concentration. Nature 325:244-246.
Hornbeck, J. W., C. W. Martin, R. S. Pierce, F. H. Bormann, G. E. Likens and J. S. Eaton. 1987. The

227.
228.
229.
230.
231.
232.

233.
234.
235.
236.

237.
238.
239.
240.
241.
242.
243.

244.

245.
246.
247.

248.
249.

northern hardwood forest ecosystem: ten years of recovery from clearcutting. USDA Forest Service,Northeastern Forest Experiment Station, NE-RP-596. 30 pp.
Likens, G. E. 1987. Acid rain: Do we know enough? p. 40. In: Environment 2000, New York State(Plenary Session).
Likens, G. E. 1987. Chemical wastes in our atmosphere – an ecological crisis. Industrial Crisis
Quarterly 1(4):13-33.
Likens, G. E. 1987. Concern for Sustained Ecological Research. Environ. Conservation 17(3):271272.
Likens, G. E. 1987. More action on acid rain. (Letter to the Editor). Poughkeepsie Journal, 22 April
1987, page 4A.
Likens, G. E. 1987. Preface. page v. In: S. O. Rohmann and N. Lilienthal (eds.). Tracing a River's
Toxic Pollution. A Case Study of the Hudson River, Phase II. An INFORM Report. 209 pp.
Likens, G. E., J. J. Cole, J. Kolasa, J. McAninch, M. McDonnell, G. G. Parker and D. L. Strayer. 1987.
Status and future of ecosystem science. Occasional Publication of the Institute of Ecosystem Studies,No. 3. Millbrook, New York. 24 pp.
Likens, G. E., W. C. Keene, J. M. Miller and J. N. Galloway. 1987. Chemistry of precipitation from aremote, terrestrial site in Australia. J. Geophys. Res. 92(D11):13,299-13,314.
Mayer, M. S. and G. E. Likens. 1987. The importance of algae in a shaded headwater stream as foodfor an abundant caddisfly (Trichoptera). J. N. Am. Benthol. Soc. 6(4):262-269.
Caraco, N., J. J. Cole, G. E. Likens, M. D. Mattson and S. Nolan. 1988. A very imbalanced nutrient
budget for Mirror Lake, New Hampshire, U.S.A. Verh. Internat. Verein. Limnol. 23:170-175.
Driscoll, C. T., N. M. Johnson, G. E. Likens and M. C. Feller. 1988. Effects of acidic deposition on thechemistry of headwater streams: a comparison between Hubbard Brook, New Hampshire, and Jamieson
Creek, British Columbia. Water Resour. Res. 24(2):195-200.
Hedin, L. O., M. S. Mayer and G. E. Likens. 1988. The effect of deforestation on organic debris dams.
Verh. Internat. Verein. Limnol. 23:1135-1141.
Likens, G. E. 1988. Information needs -- Aquatic. pp. 101-119. In: J. C. White (ed.). Acid Rain: The
Relationship Between Resources and Receptors. Elsevier Science Publishing Co., Inc.
Likens, G. E. 1988. Water Pollution. The World Book Encyclopedia 21:137-138.
Lovett, G. M., C. G. Jones and G. E. Likens. 1988. Acid rain report. (Response to P. Abelson's
Editorial, 9 October 1987). Science 239:128.
McDowell, W. H. and G. E. Likens. 1988. Origin, composition, and flux of dissolved organic carbon in
the Hubbard Brook Valley. Ecol. Monogr. 58(3):177-195.
Nodvin, S. C., C. T. Driscoll and G. E. Likens. 1988. Soil processes and sulfate loss at the Hubbard
Brook Experimental Forest. Biogeochemistry 5:185-199.
Weathers, K. C., G. E. Likens, F. H. Bormann, S. H. Bicknell, B. T. Bormann, B. C. Daube, Jr., J. S.
Eaton, J. N. Galloway, W. C. Keene, K. D. Kimball, W. H. McDowell, T. G. Siccama, D. Smiley and R.
Tarrant. 1988. Cloudwater chemistry from ten sites in North America. Environ. Sci. Technol.
22(8):1018-1026.
Weathers, K. C., G. E. Likens, F. H. Bormann, J. S. Eaton, K. Kimball, J. N. Galloway, T. G. Siccama
and D. Smiley. 1988. Chemical concentrations in cloud water from four sites in the eastern UnitedStates. pp. 345-357. In: M. H. Unsworth and D. Fowler (eds.). Acid Deposition at High Elevation
Sites. Kluwer Academic Publ.
Asbury, C. E., F. A. Vertucci, M. D. Mattson and G. E. Likens. 1989. Acidification of Adirondacklakes. Environ. Sci. Technol. 23(3):362-365.
Caraco, N., J. J. Cole and G. E. Likens. 1989. Evidence for sulfate-controlled phosphorus release fromsediments of aquatic systems. Nature 341(6240):316-318.
Driscoll, C. T., G. E. Likens, L. O. Hedin, J. S. Eaton and F. H. Bormann. 1989. Changes in thechemistry of surface waters: 25-year results at the Hubbard Brook Experimental Forest, New
Hampshire. Environ. Sci. Technol. 23(2):137-143.
Driscoll, C. T., G. E. Likens, L. O. Hedin and F. H. Bormann. 1989. A reply to C. W. Chen and L. E.
Gomez's Letter to the Editor, ‘Surface Water Chemistry.’ Environ. Sci. Technol. 23(7):754, 789.
Driscoll, C. T., G. E. Likens, L. O. Hedin and F. H. Bormann. 1989. Reply to P. J. Dillon, ‘Changes in107the chemistry of surface waters.’ Environ. Sci. Technol. 23(9):1028.
250. Driscoll, C. T., G. E. Likens, L. O. Hedin and F. H. Bormann. 1989. Reply to G. R. Holdren, Jr. and M.
R. Church, ‘Changes in the chemistry of surface waters.’ Environ. Sci. Technol. 23(9):1079-1080.
251. Fox, D. G., A. M. Bartuska, J. G. Byrne, E. Cowling, R. Fisher, G. E. Likens, S. E. Lindberg, R. A.
Linthurst, J. Messer and D. S. Nichols. 1989. A screening procedure to evaluate air pollution effects on
Class I wilderness areas. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station,
Fort Collins, Colorado. General Tech. Report RM-168, 36 pp.
252. Likens, G. E. 1989. Acid rain and its effects on sediments in lakes and streams. Hydrobiologia
176/177:331-348; Also, pp. 331-348. In: P. G. Sly and B. T. Hart (eds.). Sediment-Water Interactions,
Proc. Fourth Internat. Symposium, Kluwer Academic Publishers, Dordrecht, Belgium.
253. Likens, G. E. 1989. Alarmed by deterioration of lake shorelines [Letter to the Editor.] Vilas County
News & Review, Eagle River, Wisconsin, 1 November 1989.
254. Likens, G. E. 1989. Concluding remarks. pp. 209-210. In: G. E. Likens (ed.). Long-Term Studies in
Ecology. Springer-Verlag New York Inc.
255. Likens, G. E. 1989. Evaluating stresses on temperate forest ecosystems. pp. 161-198. In: G. B.
Marini-Bettolo (ed.). A Study Week on: A Modern Approach to the Protection of the Environment.
[Pontifical Academy of Sciences, The Vatican. 2-7 November 1989.] Pontificiae Academiae
Scientiarvm Scripta Varia 75.
256. Likens, G. E. 1989. Some aspects of air pollution on terrestrial ecosystems and prospects for the future.
Ambio 18(3):172-178.
257. Likens, G. E. 1989. Letter to the Editor in response to C. V. Runyon's, ‘Does the acid rain hypothesis
hold water?’ The Science Teacher, November, pp. 10, 12.
258. Mitchell, M. J., C. T. Driscoll, R. D. Fuller, M. B. David and G. E. Likens. 1989. Effect of whole-tree
harvesting on the sulfur dynamics of a forest soil. Soil Sci. Soc. Am. J. 53(3):933-940.
259. Vertucci, F. A. and G. E. Likens. 1989. Spectral reflectance and water quality of Adirondack Mountainregion lakes. Limnol. Oceanogr. 34(8):1660-1676.
260. Winter, T. C., J. S. Eaton and G. E. Likens. 1989. Evaluation of inflow to Mirror Lake, New
Hampshire. Water Resour. Bull. 25(5):991-1008.
261. Asbury, C. E., M. D. Mattson, F. A. Vertucci and G. E. Likens. 1990. Reply to J. R. Kramer and R. C.
Metcalf and R. W. Gerlach [Letter to the Editor], ‘Acidification to Adirondack lakes.’ Environ. Sci.
Technol. 24(3):387-390.
262. Caraco, N., J. Cole and G. E. Likens. 1990. A comparison of phosphorus immobilization in sedimentsof freshwater and coastal marine systems. Biogeochemistry 9:277-290.
263. Caraco, N. F., J. J. Cole, G. E. Likens and S. Nolan. 1990. Atmospheric inputs of phosphorus to an
oligotrophic lake. pp. 361-369. In: I. G. Poppoff, C. R. Goldman, L. S. Loeb and L. B. Leopold (eds.).
International Mountain Watershed Symposium: Subalpine Processes and Water Quality. Lake Tahoe,
June 1988.
264. Cole, J. J., N. F. Caraco and G. E. Likens. 1990. Short-range atmospheric transport: A significant
source of phosphorus to an oligotrophic lake. Limnol. Oceanogr. 35(6):1230-1237.
265. Driscoll, C. T., C. E. Johnson, T. G. Siccama and G. E. Likens. 1990. Biogeochemistry of trace metals
at the Hubbard Brook Experimental Forest, N.H. pp. 637-648. In: Proc. of 1990 EPA/A+WMA
Internat. Symp.: Measurement of Toxics and Related Air Pollutants. Air and Waste Management
Association. Pittsburgh, Pennsylvania.
266. Giblin, A. E., G. E. Likens, D. White and R. W. Howarth. 1990. Sulfur storage and alkalinity
generation in New England lake sediments. Limnol. Oceanogr. 35(4):852-869.
267. Hedin, L. O., L. Granat, G. E. Likens and H. Rodhe, 1990. Strong similarities in seasonal concentration
ratios of SO42-, NO3- and NH4+ in precipitation between Sweden and the northeastern United States.
Tellus 42B:454-462.
268. Hedin, L. O., G. E. Likens, K. M. Postek and C. T. Driscoll. 1990. A field experiment to test whetherorganic acids buffer acid deposition. Nature 345:798-800.
269. Likens, G. E. 1990. Insights from Hubbard Brook: Importance of long-term data. pp. 3-24. In: I. G.
Poppoff, C. R. Goldman, S. L. Loeb and L. B. Leopold (eds.). International Mountain WatershedSymposium: Subalpine Processes and Water Quality. Lake Tahoe, June 1988.

108

270. Likens, G. E., L. O. Hedin and T. J. Butler. 1990. Some long-term precipitation chemistry patterns atthe Hubbard Brook Experimental Forest: extremes and averages. Verh. Internat. Verein. Limnol.
24(1):128-135.
271. Likens, G. E., F. H. Bormann, L. O. Hedin, C. T. Driscoll and J. S. Eaton. 1990. Dry deposition of
sulfur: A 23-yr record for the Hubbard Brook Forest Ecosystem. Tellus 42B:319-329.
272. Mattson, M. D. and G. E. Likens. 1990. Air pressure and methane fluxes. Nature 347(6295):718-719.
273. Pierce, R. S., F. H. Bormann and G. E. Likens. 1990. The ecosystem approach to forest hydrologicalresearch. pp. 92-98. In: P. F. Ffolliott and D. P. Guertin (eds.). Proc. of a Workshop, Forest
Hydrological Resources in China. An Analytical Assessment. U.S. Man and the Biosphere Program.
Harbin, China; August 1987.
274. Westman, W. E., R. K. Peet and G. E. Likens. 1990. A Biographical Memoir: Robert H. Whittaker
1920-1980. Biographical Memoirs 59:424-444. The National Academy Press, Washington, D.C.
275. Butler, T. J. and G. E. Likens. 1991. The impact of changing regional emissions on precipitation
chemistry in the eastern United States. Atmos. Environ. 25A(2):305-315.
276. Caraco, N. F., J. J. Cole and G. E. Likens. 1991. A cross-system study of phosphorus release from lake
sediments. pp. 241-258. In: J. J. Cole, G. M. Lovett and S.E.G. Findlay (eds.). Comparative Analysis
of Ecosystems: Patterns, Mechanisms, and Theories. Springer-Verlag New York Inc.
277. Caraco, N. F., J. J. Cole and G. E. Likens. 1991. Phosphorus release from anoxic sediments: lakes thatbreak the rules. Verh. Internat. Verein. Limnol. 24(5):2985-2988.
278. Giblin, A. E., G. E. Likens and R. W. Howarth. 1991. Reply to R. Stauffer [Letter to the Editor],‘Sulfur storage and alkalinity generation in New England lake sediments.’ Limnol. Oceanogr.
36(6):1265-1271.
279. Likens, G. E. 1991. Human-accelerated environmental change. BioScience 41(3):130.
280. Likens, G. E. 1991. Some consequences of long-term human impacts on ecosystems. Revista Chilena
de Historia Natural 64(3):597-614.
281. Likens, G. E. 1991. Toxic winds: whose responsibility? pp. 136-152. In: F. H. Bormann and S. R.
Kellert (eds.). Ecology, Economics, Ethics: The Broken Circle. Yale University Press.
282. Basnet, K., G. E. Likens, F. N. Scatena and A. E. Lugo. 1992. Hurricane Hugo: damage to a tropicalrain forest in Puerto Rico. J. Tropical Ecology 8(1):47-56.
283. Caraco, N. F., J. J. Cole and G. E. Likens. 1992. New and recycled primary production in an
oligotrophic lake: Insights for summer phosphorus dynamics. Limnol. Oceanogr. 37(3):590-602.
284. Driscoll, C. T., C. E. Johnson and G. E. Likens. 1992. Patterns in the biogeochemistry at the Hubbard
Brook Experimental Forest, New Hampshire, USA. pp. 244-255. In: A. Teller, P. Mathy and J.N.R.
Jeffers (eds.). Responses of Forest to Environmental Changes. Commission of European Communities.
Elsevier Applied Science, London and New York.
285. Giblin, A. E., G. E. Likens and R. W. Howarth. 1992. The importance of reduced inorganic sulfur tothe sulfur cycle of lakes. In: E. T. Degens, S. Kempe, A. Lein and Y. Sorokin (eds.). Interactions of
Biogeochemical Cycles in Aqueous Ecosystems. Proc. SCOPE/UNEP Workshop at Listvyanka/Irkutsk,
USSR. September 1988.
286. Hultberg, H. and G. E. Likens. 1992. Sulphur deposition to forested catchments in northern Europe andNorth America -- large-scale variations and long-term dynamics. pp. 1343-1365. In: S. E. Schwartz
and W.G.N. Slinn (coordinators). Fifth Internat. Conf. on Precipitation Scavenging and AtmosphereSurface Exchange. Vol. 3--The Summers Volume: Applications and Appraisals. Hemisphere PublishingCorp.
287. Likens, G. E. 1992. Clean Air Act did not stop acid rain. p. 5. In: Earth Summit Times.
288. Likens, G. E. 1992. Meromictic lake. pp. 649-651. In: McGraw-Hill Encyclopedia of Science andTechnol., 7th edition. Vol. 10. McGraw-Hill Publishing Co.
289. Likens, G. E. 1992. Some applications on the ecosystem approach to environmental problems andresource management. pp. 16-30. In: A. Teller, P. Mathy and J.N.R. Jeffers (eds.). Responses of Forest
Ecosystems to Environmental Changes. Commission of European Communities. Elsevier Applied
Science, London and New York.
290. Lovett, G. M., G. E. Likens and S. S. Nolan. 1992. Dry deposition of sulfur to the Hubbard Brook
Experimental Forest: a preliminary comparison of methods. pp. 1391-1401. In: S. E. Schwartz and

109

291.

292.

293.
294.
295.
296.
297.

298.

299.
300.
301.
302.

303.

304.
305.
306.
307.
308.

309.
310.
311.

110

W.G.N. Slinn (coordinators). Fifth Internat. Conf. on Precipitation Scavenging and Atmosphere-Surface
Exchange. Vol. 3--The Summers Volume: Applications and Appraisals. Hemisphere Publishing Corp.
Weathers, K. C., G. M. Lovett and G. E. Likens. 1992. The influence of a forest edge on clouddeposition. pp. 1415-1423. In: S. E. Schwartz and W.G.N. Slinn (coordinators). Fifth Internat. Conf.
on Precipitation Scavenging and Atmosphere-Surface Exchange. Vol. 3--The Summers Volume:
Applications and Appraisals. Hemisphere Publishing Corp.
Basnet, K., F. N. Scatena, G. E. Likens and A. E. Lugo. 1993. Ecological consequences of root graftingin tabonuco (Dacryodes excelsea Vahl) trees in the Luquillo Experimental Forest, Puerto Rico.
Biotropica 25:28-35.
Bukaveckas, P., G. E. Likens, D. C. Buso and T. C. Winter. 1993. Hydrologic controls of chemical flux
rates in the Mirror Lake watershed. Verh. Internat. Verein. Limnol. 25(1):419-422.
Caraco, N. F., J. J. Cole and G. E. Likens. 1993. Sulfate control of phosphorus availability in lakes: atest and re-evaluation of Hasler and Einsele's Model. Hydrobiologia 253:275-280.
Likens, G. E. and P. M. Groffman. 1993. Integrated regional models [workshop review]. Bull. Ecol.
Soc. Amer. 74(3):226-228.
Mattson, M. D. and G. E. Likens. 1993. Redox reactions of organic matter decomposition in a soft
water lake. Biogeochemistry 19:149-172.
Harriman, R., G. E. Likens, H. Hultberg and C. Neal. 1994. Influence of management practices incatchments on freshwater acidification: Afforestation in the United Kingdom and North America. pp.
83-101. In: C.E.W. Steinberg and R. F. Wright (eds.). Acidification of Freshwater Ecosystems:
Implications for the Future. Dahlem Konferenzen, Berlin, Germany. John Wiley & Sons Ltd.
Hedin, L. O., L. Granat, G. E. Likens, T. A. Buishand, J. N. Galloway, T. J. Butler and H. Rodhe. 1994.
Steep declines in atmospheric base cations in regions of Europe and North America. Nature 367:351354.
Likens, G. E. 1994. Human-Accelerated Environmental Change--An Ecologist's View. 1994 Australia
Prize Winner Presentation. Murdoch University, Perth, Australia. 16 pp.
Likens, G. E. 1994. Pioneering the ecosystem approach. Limnology News [Winter 1994] 7:1-3.
Likens, G. E. 1994. Watersheds. pp. 812-813. In: R. A. Eblen and W. R. Eblen (eds.). The
Encyclopedia of the Environment. Houghton Mifflin Company, New York.
Likens, G. E., C. T. Driscoll, D. C. Buso, T. G. Siccama, C. E. Johnson, D. F. Ryan, G. M. Lovett, T.
Fahey and W. A. Reiners. 1994. The biogeochemistry of potassium at Hubbard Brook.
Biogeochemistry 25:61-125.
Siccama, T. G., S. P. Hamburg, M. A. Arthur, R. D. Yanai, F. H. Bormann and G. E. Likens. 1994.
Corrections to the allometric equations and plant tissue chemistry for the Hubbard Brook Experimental
Forest. Ecology 75(1):246-248.
Butler, T. J. and G. E. Likens. 1995. A direct comparison of throughfall plus stemflow, and estimates ofdry and total deposition for sulfur and nitrogen. Atmospheric Environment 29(11):1253-1266.
Christ, M., Yimin Zhang, G. E. Likens and C. T. Driscoll. 1995. Nitrogen retention capacity of anorthern hardwood forest soil under ammonium sulfate additions. Ecol. Appl. 5(3):802-812.
Johnson, C. E., T. G. Siccama, C. T. Driscoll, G. E. Likens and R. E. Moeller. 1995. Changes in leadbiogeochemistry in response to decreasing atmospheric inputs. Ecol. Appl. 5(3):813-822.
Likens, G. E. 1995. Environmental issues in the 1990s. Australian Academy of Technological Sciencesand Engineering - ATS Focus 85:2-3.
Likens, G. E. 1995. Sustained ecological research and the protection of ecosystems. pp. 13-21. In: T.
B. Herman, S. Bondrup-Nielsen, J.H.M. Willison and N.W.P. Munro (eds.). Ecosystem Monitoring andProtected Areas. Proc. International Conference on Science and the Management of Protected Areas.
Wolfville, Nova Scotia, Canada.
Likens, G. E. 1995. Water pollution [revised and reprinted]. pp. 137-139. In: The World Book
Encyclopedia, World Book Publishing, Vol. 21.
Mattson, M. D. and G. E. Likens. 1995. Comment on ‘Recent trends in the acid-base status of surface
waters in Maine, USA--Kahl et al. 1993’. Water, Air and Soil Pollution 83(1/2):97-99.
Ochs, C. A., J. J. Cole and G. E. Likens. 1995. Population dynamics of bacterioplankton in an
oligotrophic lake. J. Plankton Research 17(2):365-391.

312. Pardo, L. H., C. T. Driscoll and G. E. Likens. 1995. Patterns of nitrate loss from a chronosequence ofclear-cut watersheds. J. Water, Air, Soil Pollution 85/3:1659-1664.
313. Weathers, K. C., G. M. Lovett and G. E. Likens. 1995. Cloud deposition to a spruce forest edge.
Atmospheric Environment 29(6):665-672.
314. Galloway, J. N., W. C. Keene and G. E. Likens. 1996. Processes controlling the composition of
precipitation at a remote southern hemispheric location: Torres del Paine National Park, Chile. J.
Geophys. Res. 101(D3):6883-6897.
315. Hedin, L. O. and G. E. Likens. 1996. Atmospheric dust and acid rain. Sci. Amer. 275(6):88-92.
316. Holmes, R. T. and G. E. Likens. 1996. A checklist of organisms of the Hubbard Brook watershedecosystems, including Mirror Lake. Second Edition. March 1996, 56 pp.
317. Likens, G. E. 1996. Air pollution and forest health. Environ. Review 3(8):1-6.
318. Likens, G. E., C. T. Driscoll and D. C. Buso. 1996. Long-term effects of acid rain: response andrecovery of a forest ecosystem. Science 272:244-246.
319. Likens, G. E., C. T. Driscoll and D. C. Buso. 1996. Acid rain revisited? Science 273:293-295.
320. Mitchell, M. J., C. T. Driscoll, J. S. Kahl, G. E. Likens, P. S. Murdoch and L. H. Pardo. 1996. Climatic
control of nitrate loss from forested watersheds in the Northeast United States. Environ. Sci. Technol.
30(8):2609-2612.
321. Romanowicz, R. B., C. T. Driscoll, T. J. Fahey, C. E. Johnson, G. E. Likens and T. G. Siccama. 1996.
Changes in the biogeochemistry of potassium following a whole-tree harvest. Soil Sci. Soc. Amer. J.
60:1664-1674.
322. Berger, T. W., S. L. Tartowski and G. E. Likens. 1997. Trifluoroacetate retention in a northernhardwood forest soil. Environ. Sci. Technol. 31(7):1916-1921.
323. Findlay, S., G. E. Likens, L. Hedin, S. G. Fisher and W. H. McDowell. 1997. Organic matter dynamics
in Bear Brook, Hubbard Brook Experimental Forest, New Hampshire, USA. pp. 43-46. In: J. R.
Webster and J. L. Meyer (eds.). Stream Organic Matter Budgets. J. North Amer. Bentholog. Soc. 16(1).
324. Likens, G. E. 1997. Access roads endanger ecosystems. [Letter to the Editor]. Millbrook Round Table,
December 11, 1997. p. A13.
325. Likens, G. E., S. L. Tartowski, T. W. Berger, D. G. Richey, C. T. Driscoll, H. G. Frank and A. Klein.
1997. Transport and fate of trifluoroacetate in upland forest and wetland ecosystems. Proc. National
Academy of Sciences 94:4499-4503.
326. Ostfeld, R. S., S.T.A. Pickett, M. Shachak and G. E. Likens. 1997. Defining the scientific issues. pp. 310. In: S.T.A. Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens (eds.). The Ecological Basis ofConservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall, New York.
327. Ostfeld, R. S., S.T.A. Pickett, M. Shachak and G. E. Likens. 1997. Themes [in Biodiversity and its
Ecological Linkages]. pp. 123-124. In: S.T.A. Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens(eds.). The Ecological Basis of Conservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman& Hall, New York.
328. Ostfeld, R. S., S.T.A. Pickett, M. Shachak and G. E. Likens. 1997. Themes [in Toward a New
Conservation Theory]. p. 201. In: S.T.A. Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens (eds.).
The Ecological Basis of Conservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall,New York.
329. Ostfeld, R. S., S.T.A. Pickett, M. Shachak and G. E. Likens. 1997. Themes [in Application ofConservation Ecology]. p. 297. In: S.T.A. Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens (eds.).
The Ecological Basis of Conservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall,New York.
330. Pickett, S.T.A., R. S. Ostfeld, M. Shachak and G. E. Likens. 1997. Themes [in Foundations for aComprehensive Conservation Theory]. Application of Conservation Ecology]. pp. 81-82. In: S.T.A.
Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens (eds.). The Ecological Basis of Conservation:
Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall, New York.
331. Pickett, S.T.A., R. S. Ostfeld, M. Shachak and G. E. Likens. 1997. Themes [in Synthesis and a Forward
Look]. pp. 361-362. In: S.T.A. Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens (eds.). The
Ecological Basis of Conservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall, New
York.

111

332. Pickett, S.T.A., M. Shachak, R. S. Ostfeld and G. E. Likens. 1997. Toward a comprehensive
conservation theory. pp. 384-399. In: S.T.A. Pickett, R. S. Ostfeld, M. Shachak and G. E. Likens (eds.).
The Ecological Basis of Conservation: Heterogeneity, Ecosystems, and Biodiversity. Chapman & Hall,New York.
333. Richey, D. G., C. T. Driscoll and G. E. Likens. 1997. Soil retention of trifluoroacetate. Environ. Sci.
Technol. 31(6):1723-1727.
334. Richey, D. G., C. T. Driscoll and G. E. Likens. 1997. Soil retention of TFA in LTER soil. Network
News, U.S. LTER Newsletter, Issue 20:10-11.
335. Vitousek, P.M., J. D. Aber, R. W. Howarth, G. E. Likens, P. A. Matson, D. W. Schindler, W. H.
Schlesinger and G. D. Tilman. 1997. Human alteration of the global nitrogen cycle: causes andconsequences. Issues in Ecology 1:1-15.
336. Vitousek, P.M., J. D. Aber, R. W. Howarth, G. E. Likens, P. A. Matson, D. W. Schindler, W. H.
Schlesinger and D. G. Tilman. 1997. Human alteration of the global nitrogen cycle: sources andconsequences. Ecological Applications 7(3):737-750.
337. Weathers, K. C. and G. E. Likens. 1997. Clouds in southern Chile: An important source of nitrogen tonitrogen-limited ecosystems? Environ. Sci. Technol. 31(1):210-213.
338. Bukaveckas, P. A., G. E. Likens, T. C. Winter and D. C. Buso. 1998. A comparison of methods forderiving solute flux rates using long-term data from streams in the Mirror Lake watershed. Water, Air,
Soil Pollut. 105:277-293.
339. Butler, T. J. and G. E. Likens. 1998. Weekly and daily precipitation chemistry network comparisons in
the eastern U.S.: NADP/NTN vs. MAP3S/AIRMoN. Atmospheric Environment 32(21):3749-3765.
340. Driscoll, C. T., G. E. Likens and M. R. Church. 1998. Recovery of surface waters in the northeastern
U.S. from decreases in atmospheric deposition of sulfur. Water, Air, Soil Pollut.105:319-329.
341. Likens, G. E. 1998. Limitations to intellectual progress in ecosystem science. pp. 247-271. In: M. L.
Pace and P. M. Groffman (eds.)., Successes, Limitations and Frontiers in Ecosystem Science. 7th Cary
Conference, Institute of Ecosystem Studies, Millbrook, New York. Springer-Verlag New York Inc.
342. Likens, G. E. and K. Fallon Lambert. 1998. The importance of long-term data in addressing regional
environmental issues. Northeastern Naturalist 5(2):127-136.
343. Likens, G. E., C. T. Driscoll, D. C. Buso, T. G. Siccama, C. E. Johnson, G. M. Lovett, T. J. Fahey, W.
A. Reiners, D. F. Ryan, C. W. Martin and S. W. Bailey. 1998. The biogeochemistry of calcium at
Hubbard Brook. Biogeochemistry 41(2):89-173.
344. Likens, G. E., K. C. Weathers, T. J. Butler and D. C. Buso. 1998. Solving the acid rain problem.
Science 282(5396):1991-1992.
345. Weathers, K. C. and G. E. Likens. 1998. Acid rain. pp. 1549-1561. In: W. N. Rom (ed.).
Environmental and Occupational Medicine, 3rd edition. Lippincott-Raven Publ., Philadelphia.
346. Weathers, K. C., G. M. Lovett, G. E. Likens and N. Caraco. 1998. Cloud water in southern Chile:
Whence come the nutrients? pp. 313-315. In: R. S. Schemenauer and J. Bridgman (eds.). FirstInternational Conference on Fog and Fog Collection. IDRC, Ottawa, Canada.
347. Yimin Zhang, M. J. Mitchell, M. Christ, H. R. Krouse and G. E. Likens. 1998. Stable sulfur isotopes inbiogeochemistry at Hubbard Brook Experimental Forest, New Hampshire. Biogeochemistry 41:259-275.
348. Alewell, C., M. J. Mitchell, G. E. Likens and H. R. Krouse. 1999. Sources of stream sulfate at the
Hubbard Brook Experimental Forest: Long-term analyses using stable isotopes. Biogeochemistry
44:281-299.
349. Berger, T. W. and G. E. Likens. 1999. Effects of acid anion additions (trifluoroacetate and bromide) on
soil solution chemistry of a northern hardwood forest soil. Water, Air and Soil Pollution 116:479-499.
350. Christ, M. J., C. T. Driscoll and G. E. Likens. 1999. Watershed- and plot-scale tests of the mobile anion
concept. Biogeochemistry 47(3):335-353.
351. Holmes, R. T. and G. E. Likens. 1999. Organisms of Hubbard Brook Valley, New Hampshire. USDA
Forest Service, Northeastern Research Station, General Tech. Report NE-257. 32 pp.
352. Joyce, L. A., J. J. Landsberg, M. Stafford Smith, J. Ben-Asher, J. R. Cavazos Doria, K. Lajtha, G. E.
Likens, A. Perevolotsky and U. Safriel. 1999. Ecosystem-level consequences of management options.
pp. 97-116. In: T. W. Hoekstra and M. Shachak (eds.). Arid Lands Management – Toward Ecological
Sustainability. Univ. Illinois Press, Urbana and Chicago.

112353. Likens, G. E. 1999. Afterword: Reflections and Needs. pp. 269-272. In: T. W. Hoekstra and M.
Shachak (eds.). Arid Lands Management – Toward Ecological Sustainability. Univ. Illinois Press,
Urbana and Chicago.
354. Likens, G. E. 1999. The science of nature, the nature of science: Long-term ecological studies at
Hubbard Brook. Proc.. American Philosophical Society 143(4):558-572.
355. Rosenberry, D. O., P. A. Bukaveckas, D. C. Buso, G. E. Likens, A. M. Shapiro and T. C. Winter. 1999.
Movement of road salt to a small New Hampshire lake. Water, Air, and Soil Pollut. 109:179-206.
356. Steinhart, G. S., G. E. Likens and D. Soto. 1999. Nutrient limitation in Lago Chaiquenes (ParqueNacional Alerce Andino, Chile): Evidence from nutrient enrichment experiments and physiologicalassays. Revista Chilena de Historia Natural 72(4): 559-568.
357. Yimin Zhang, M. J. Mitchell, C. T. Driscoll and G. E. Likens. 1999. Changes in soil sulfur constituentsin a forested watershed eight years after whole-tree harvesting. Canadian Journal of Forest Research
29:356-364.
358. Alewell, C., M. J. Mitchell, G. E. Likens and H. R. Krouse. 2000. Assessing the origin of sulfatedeposition at the Hubbard Brook Experimental Forest. The Journal of Environmental Quality
29(3):759-767.
359. Buso, D. C., G. E. Likens and J. S. Eaton. 2000. Chemistry of precipitation, streamwater and lakewaterfrom the Hubbard Brook Ecosystem Study: A record of sampling protocols and analytical procedures.
General Tech. Report NE-275. Newtown Square, PA: USDA Forest Service, Northeastern Research
Station. 52 pp.
360. Campbell, J. L., J. W. Hornbeck, W. H. McDowell, D. C. Buso, J. B. Shanley and G. E. Likens. 2000.
Dissolved organic nitrogen budgets for upland, forested ecosystems in New England. Biogeochemistry49:123-142.
361. Hall, R. O., Jr. and G. E. Likens. 2000. Ecological implications of high discharge variability in streamsof the Hubbard Brook Experimental Forest. Verh. Internat. Verein. Limnol. 27:2353-2358.
362. Johnson, C. E., C. T. Driscoll, T. G. Siccama and G. E. Likens. 2000. Element fluxes and landscapeposition in a northern hardwood forest watershed ecosystem. Ecosystems 3:159-184.
363. Larison, J. R., G. E. Likens, J. W. Fitzpatrick and J. G. Crock. 2000. Cadmium toxicity among wildlife
in the Colorado Rocky Mountains. Nature 406:181-183.
364. Lewis, G. P. and G. E. Likens. 2000. Low stream nitrate concentrations associated with oak forests on
the Allegheny High Plateau of Pennsylvania. Water Resources Research 36(10):3091-3094.
365. Likens, G. E. 2000. Earth resurgent. Yale Alumni Magazine Letters 64(1):12-13.
366. Likens, G. E. 2000. A long-term record of ice cover for Mirror Lake, New Hampshire: effects ofglobal warming? Verh. Internat. Verein. Limnol. 27(5):2765-2769.
367. Martin, C. W., G. E. Likens and D. C. Buso. 2000. Comparison of long-term precipitation chemistrymeasurements at the Hubbard Brook Experimental Forest, New Hampshire. Water, Air, and Soil Pollut.
120(3-4):359-379.
368. Martin, C. W., J. W. Hornbeck, G. E. Likens and D. C. Buso. 2000. Impacts of intensive harvesting onhydrology and nutrient dynamics of northern hardwood forests. Can. J. For. Res. 57(Suppl. 2):19-29.
369. Steinhart, G. S., G. E. Likens and P. M. Groffman. 2000. Denitrification in stream sediments in fivenortheastern (USA) streams. Verh. Internat. Verein. Limnol. 27(3):1331-1336.
370. Weathers, K. C., G. M. Lovett, G. E. Likens and N. M. Caraco. 2000. Cloudwater inputs of nitrogen toforest ecosystems in southern Chile: Forms, fluxes and sources. Ecosystems 3:590-595.
371. Weathers, K. C., G. M. Lovett, G. E. Likens and R. Lathrop. 2000. The effect of landscape features on
deposition to the Hunter Mountain, Catskill Mountains, New York. Ecological Applications 10(2):528540.
372. Berger, T. W., C. Eagar, G. E. Likens and G. Stingeder. 2001. Effects of calcium and aluminum
chloride additions on foliar and throughfall chemistry in sugar maples. Forest Ecology and Management
149:75-90.
373. Butler, T. J., G. E. Likens and B.J.B. Stunder. 2001. Regional-scale impacts of Phase I of the Clean Air
Act Amendments in the USA: the relation between emissions and concentrations, both wet and dry.
Atmospheric Environment 35(6):1015-1028.
374. Driscoll, C. T., G. B. Lawrence, A. J. Bulger, T. J. Butler, C. S. Cronan, C. Eagar, K. Fallon Lambert, G.

113

375.

376.

377.
378.
379.
380.

381.
382.

383.
384.
385.

386.
387.

388.
389.
390.
391.

392.
393.

394.

395.

114

E. Likens, J. L. Stoddard and K. C. Weathers. 2001. Acid Rain Revisited: advances in scientificunderstanding since the passage of the 1970 and 1990 Clean Air Act Amendments. Hubbard Brook
Research Foundation. Science Links Publication. Vol. 1, No. 1. pp. 1-20.
Driscoll, C. T., G. B. Lawrence, A. J. Bulger, T. J. Butler, C. S. Cronan, C. Eagar, K. Fallon Lambert, G.
E. Likens, J. L. Stoddard and K. C. Weathers. 2001. Acidic deposition in the northeastern UnitedStates: sources and inputs, ecosystem effects, and management strategies. BioScience 51(3):180-198.
Gbondo-Tugbawa, S. S., C. T. Driscoll, J. D. Aber and G. E. Likens. 2001. Evaluation of an integrated
biogeochemical model (PnET-BGC) at a northern hardwood forest ecosystem. Water Resour. Res.
37(4):1057-1070.
Hall, R. O., Jr., G. E. Likens and H. M. Malcom. 2001. Trophic basis of invertebrate production in two
streams at the Hubbard Brook Experimental Forest. J. N. Amer. Benthol. Soc. 29(3):432-447.
Hall, R. O., Jr., K. H. Macneale, E. S. Bernhardt, M. Field and G. E. Likens. 2001. Biogeochemical
responses of two forest streams to a two-month calcium addition. Freshwater Biology 46(3):291-302.
Likens, G. E. 2001. Arthur D. Hasler – A personal note. Resolution of Respect, Bull. Ecol. Soc. Amer.
82(3):173.
Likens, G. E. 2001. Biogeochemistry, the watershed approach: some uses and limitations. In:
Frontiers of Catchment Biogeochemistry. CSIRO Land and Water, Canberra, Australia. Marine andFreshwater Research 52(1):5-12
Likens, G. E. 2001. Ecosystems: Energetics and Biogeochemistry. pp. 53-88. In: W. J. Kress and G.
Barrett (eds.). A New Century of Biology. Smithsonian Institution Press, Washington and London.
Likens, G. E. 2001. Eugene P. Odum, the ecosystem approach, and the future. pp. 309-328. In: G. W.
Barrett and T. L. Barrett (eds.). Holistic Science: The Evolution of the Georgia Institute of Ecology(1940-2000). Taylor & Francis Publishing, New York.
Likens, G. E. 2001. Watersheds. pp. 1370-1371. In: R. A. Eblen and W. R. Eblen (eds.) The
Environment Encyclopedia, Vol. 10. Marshall Cavendish: Tarrytown, NY .
Likens, G. E., T. J. Butler and D. C. Buso. 2001. Long- and short-term changes in sulfate deposition:
Effects of The 1990 Clean Air Act Amendments. Biogeochemistry 52(1):1-11.
Mitchell, M. J., B. Mayer, S. W. Bailey, J. W. Hornbeck, C. Alewell, C. T. Driscoll and G. E. Likens.
2001. Use of stable isotope ratios for evaluating sulfur sources and losses at the Hubbard Brook
Experimental Forest. Water, Air and Soil Pollution 130:75-86.
Scott, N. S., G. E. Likens, J. S. Eaton and T. G. Siccama. 2001. Loss of trace metals following wholetree harvest of a northeastern deciduous forest. Biogeochemistry 54:197-217.
Aber, J. D., S. V. Ollinger, C. T. Driscoll, G. E. Likens, R. T. Holmes, R. J. Freuder and C. L. Goodale.
2002. Inorganic nitrogen losses from a forested ecosystem in response to physical, chemical, biotic, andclimatic perturbations. Ecosystems 5(7):648-658.
Barrett, G. W. and G. E. Likens. 2002. Eugene P. Odum: Pioneer of Ecosystem Ecology. BioScience
52(11):1047-1048.
Bernhardt, E. S. and G. E. Likens. 2002. Dissolved organic carbon enrichment alters nitrogen dynamics
in a forest stream. Ecology 83(6):1689-1700.
Bernhardt, E. S., R. O. Hall, Jr. and G. E. Likens. 2002. Whole-system estimates of nitrification andnitrate uptake in streams of the Hubbard Brook Experimental Forest. Ecosystems 5(5):419-430.
Blum, J. D., A. Klaue, C. A. Nezat, C. T. Driscoll, C. E. Johnson, T. G. Siccama, C. Eagar, T. J. Fahey
and G. E. Likens. 2002. Mycorrhizal weathering of apatite as an important calcium source in base-poor
forest ecosystems. Nature 417:729-731.
Dijkstra, F. A., N. van Breemen, A. G. Jongmans, G. R. Davies and G. E. Likens. 2002. Calcium
weathering in forested soils and the effect of different tree species. Biogeochemistry 62(3):253-275.
Driscoll, C. T., G. B. Lawrence, A. J. Bulger, T. J. Butler, C. S. Cronan, C. Eagar, K. F. Lambert, G. E.
Likens, J. L. Stoddard and K. C. Weathers. 2002. Response to W. E. Sharpe’s “Acid deposition
explains sugar maple decline in the East”. BioScience 52(1):5-6.
Gbondo-Tugbawa, S. S., C. T. Driscoll, M. J. Mitchell, J. D. Aber and G. E. Likens. 2002. A model tosimulate the response of a northern hardwood forest ecosystem to changes in S deposition. Ecol. Appl.
12(1):8-23.
Gilliland, A. B., T. J. Butler and G. E. Likens. 2002. Monthly and annual bias in weekly (NADP/NTN)

396.
397.

398.

399.
400.
401.
402.
403.

404.

405.

406.
407.
408.
409.
410.
411.

412.
413.
414.

415.

416.

versus daily (AIRMoN) precipitation chemistry data in the Eastern USA. Atmos. Environ. 36:51975206.
• nominated by NOAA Director for NOAA OAR “outstanding paper award”, 2005
Hall, R. O., Jr., E. S. Bernhardt and G. E. Likens. 2002. Relating nutrient uptake with transient storage
in forested mountain streams. Limnology and Oceanography 47(1):255-265.
Kelly, V. R., G. M. Lovett, K. C. Weathers and G. E. Likens. 2002. Trends in atmosphericconcentration and deposition compared to regional and local pollutant emissions at a rural site insoutheastern New York, USA. Atmospheric Environment 36:1569-1575.
Kobe, R. K., G. E. Likens and C. Eagar. 2002. Tree seedling growth and mortality responses tomanipulations of calcium and aluminum in a northern hardwood forest. Canadian Journal of Forest
Research 32:954-966.
Likens, G. E. 2002. AIBSnews: AIBS Active in Ohio Science Standards Battle. BioScience
52(8):755-756.
Likens, G. E. 2002. Arthur Davis Hasler, 1908-2001: A Biographical Memoir. National Academy of
Sciences Biographical Memoirs, The National Academy Press, Washington, DC. Vol. 82, 14 pp.
Likens, G. E. 2002. The new AIBS. Editorial, BioScience 52(1):3.
Likens, G. E. 2002. A thimbleful of powder. Editorial, BioScience 52(7):547.
Likens, G. E., D. C. Buso and J. W. Hornbeck. 2002. Variation in chemistry of stream water and bulk
deposition across the Hubbard Brook Valley, New Hampshire, USA. Verh. Internat. Verein. Limnol.
28(1):402-409.
Likens, G. E., C. T. Driscoll, D. C. Buso, M. J. Mitchell, G. M. Lovett, S. W. Bailey, T. G. Siccama, W.
A. Reiners and C. Alewell. 2002. The biogeochemistry of sulfur at Hubbard Brook. Biogeochemistry
60(3):235-316.
Macneale, K. H., G. E. Likens and B. L. Peckarsky. 2002. Feeding strategy of an adult stonefly(Plecoptera): implications for egg production and dispersal. Verh. Internat. Verein. Limnol.28(2):11401146.
Marino, R., F. Chan, R. W. Howarth, M. Pace and G. E. Likens. 2002. Ecological and biogeochemicalinteractions constrain planktonic nitrogen fixation in estuaries. Ecosystems 5(7):719-724.
Stearns, F. W. and G. E. Likens. 2002. One hundred years of recovery of a pine forest in northern
Wisconsin. Amer. Midl. Natur.148(1):2-19.
Steinhart, G. S., G. E. Likens and D. Soto. 2002. Physiological indicators of nutrient deficiency inphytoplankton in southern Chilean lakes. Hydrobiologia 489:21-27.
Stelzer, R. S., G. E. Likens, D. C. Buso and J. H. McCutchan. 2002. Seasonal variation of phosphorus
in precipitation at Hubbard Brook Experimental Forest. Verh. Internat. Verein. Limnol. 28:1211-1215.
Bailey, S. W., D. C. Buso and G. E. Likens. 2003. Implications of sodium mass balance for interpretingthe calcium cycle of a forested ecosystem. Ecology 84(2):471-484.
Bernhardt, E. S., G. E. Likens, D. C. Buso and C. T. Driscoll. 2003. In-stream uptake dampens effects
of major forest disturbance on watershed nitrogen export. Proceedings of National Academy of Sciences
100(18):10304-10308.
Butler, T. J., G. E. Likens, F. M. Vermeylen and B.J.B. Stunder. 2003. The relation between NOx
emissions and precipitation NO3- in the eastern USA. Atmos. Environ. 37(15):2093-2104.
Caraco, N. F., J. J. Cole, G. E. Likens, G. M. Lovett and K. C. Weathers. 2003. Variation in NO3 export
from flowing waters of vastly different sizes: Does one model fit all? Ecosystems 6(4):344-352.
Fitzhugh, R. D., G. E. Likens, C. T. Driscoll, M. J. Mitchell, P. M. Groffman, T. J. Fahey and J. P.
Hardy. 2003. Role of soil freezing events in interannual patterns of stream chemistry at the Hubbard
Brook Experimental Forest, New Hampshire. Environ. Sci. Tech. 37:1575-1580.
Harris, G. P., S. W. Bigelow, J. J. Cole, H. Cyr, L. L. Janus, A. P. Kinzig, J. F. Kitchell, G. E. Likens, K.
H. Reckhow, D. Scavia, D. Soto, L. M. Talbot and P. H. Templer. 2003. The role of models inecosystem management. pp. 299-307. In: C. D. Canham, J. J. Cole and W. K. Lauenroth (eds).
Models in Ecosystem Science. Cary Conference IX, Institute of Ecosystem Studies, Millbrook, NY.
Princeton University Press.
Houlton, B. Z., C. T. Driscoll, T. J. Fahey, G. E. Likens, P. M. Groffman, E. S. Bernhardt and D. C.
Buso. 2003. Nitrogen dynamics in ice storm-damaged forest ecosystems: Implications for nitrogen

115

limitation theory. Ecosystems 6(5):431-443.
417. Likens, G. E. 2003. Use of long-term data, mass balances and stable isotopes in watershedbiogeochemistry: The Hubbard Brook model. Gayana Botanica 60(1):3-7.
418. Likens, G. E. and F. H. Bormann. 2003. Environmental challenges in the Twenty-First Century and ourrespect for nature. 2003 Blue Planet Prize Commemorative Lecture, Asahi Glass Foundation, Tokyo,
Japan.
419. Marino, R., R. W. Howarth, F. Chan, J. J. Cole and G. E. Likens. 2003. Sulfate inhibition ofmolybdenum-dependent nitrogen fixation by planktonic cyanobacteria under seawater conditions: A
non-reversible effect. Hydrobiologia 500:277-293.
420. Stelzer, R. S., J. Heffernan and G. E. Likens. 2003. The influence of dissolved nutrients and particulateorganic matter quality on microbial respiration and biomass in a forest stream. Freshwater Biology
48:1925-1937.
421. Winter, T. C., D. C. Buso, D. O. Rosenberry, G. E. Likens, A. M. Sturrock, Jr. and D. P. Mau. 2003.
Evaporation determined by the energy-budget method for Mirror Lake, New Hampshire. Limnol.
Oceanogr. 48(3):995-1009.
422. Bernhardt, E. S. and G. E. Likens. 2004. Controls on periphyton biomass in heterotrophic streams.
Freshwater Biology 49:14-27.
423. Campbell, J. L., J. W. Hornbeck, M. J. Mitchell, M. B. Adams, M. S. Castro, C. T. Driscoll, J. S. Kahl, J.
N. Kochenderfer, G. E. Likens, J. A. Lynch, P. S. Murdoch, S. J. Nelson, J.B. Shanley. 2004. Inputoutput budgets of inorganic nitrogen for 24 forest watersheds in the Northeastern United States: A
review. Water, Air, & Soil Pollution 151:373-396.
424. Driscoll, C. T., G. B. Lawrence, A. J. Bulger, T. J. Butler, C. S. Cronan, C. Eagar, K. F. Lambert, G. E.
Likens, J. L. Stoddard and K. C. Weathers. 2004. Acidic deposition in the northeastern United States:
Sources and inputs, ecosystem effects and management strategies. pp. 159-190. In: J. M. Gunn, R. J.
Steedman, and R. A. Ryder (eds.). Boreal Shield Watersheds, Section III: Biological Effects andManagement Reactions. Lewis Publishers.
425. Groffman, P. M., C. T. Driscoll, C. Eagar, M. C. Fisk, T. J. Fahey, R. T. Holmes, G. E. Likens and L.
Pardo. 2004. A new governance structure for the Hubbard Brook Ecosystem Study. Bull. Ecol. Soc.
Amer. 85(1):5-6.
426. Groffman, P. M., C. T. Driscoll, G. E. Likens, T. J. Fahey, R. T. Holmes, C. Eagar and J. D. Aber. 2004.
Nor gloom of night: A new conceptual model for the Hubbard Brook Ecosystem Study. BioScience
54(2):139-148.
427. Likens, G. E. 2004. Biogeochemistry: Some opportunities and challenges for the future. Water, Air
and Soil Pollution: Focus 4(2-3):5-24.
428. Likens, G. E. 2004. Meromictic lakes. McGraw-Hill Encyclopedia.
429. Likens, G. E. 2004. Perils of a thirsty city. Editorial, Herald Sun, 9 April 2004.
430. Likens, G. E. 2004. Some perspectives on long-term biogeochemical research from the Hubbard Brook
Ecosystem Study. Ecology 85(9):2355-2362.
431. Likens, G. E., B. K. Dresser and D. C. Buso. 2004. Short-term, temperature response in forest floor andsoil to ice storm disturbance in a northern hardwood forest. Northern Journal of Applied Forestry
21(4):209-219.
432. Likens, G. E., D. C. Buso, B. K. Dresser, E. S. Bernhardt, R. O. Hall, Jr., K. H. Macneale and S. W.
Bailey. 2004. Buffering an acidic stream in New Hampshire with a silicate mineral. Restoration
Ecology 12(3):419-428.
433. Macneale, K. H., B. L. Peckarsky and G. E. Likens. 2004. Contradictory results from different methods
for measuring direction of insect flight. Freshwater Biology 49:1260-1268.
434. Peters, S. C., J. D. Blum, C. T. Driscoll and G. E. Likens. 2004. Dissolution of wollastonite during theexperimental manipulation of Hubbard Brook Watershed 1. Biogeochemistry 67:309-329.
435. Bernhardt, E. S., G. E. Likens, R. O. Hall, Jr., D. C. Buso, S. G. Fisher, T. M. Burton, J. L. Meyer, W. H.
McDowell, M. S. Mayer, W. B. Bowden, S.E.G. Findlay, K. H. Macneale, R. S. Stelzer and W. H.
Lowe. 2005. Can’t see the forest for the stream? In-stream processing and terrestrial nitrogen exports.
BioScience 55(3):219-230.
436. Butler, T. J., G. E. Likens, F. M. Vermeylen and B.J.B. Stunder. 2005. The impact of changing nitrogen

116

437.

438.

439.

440.
441.
442.

443.
444.
445.
446.
447.

448.
449.
450.
451.
452.

453.
454.
455.

456.

457.

oxide emissions on wet and dry nitrogen deposition in the northeastern USA. Atmospheric Environment
39:4851-4862.
Fahey, T. J., T. G. Siccama, C. T. Driscoll, G. E. Likens, J. Campbell, C. E. Johnson, J. D. Aber, J. J.
Cole, M. C. Fisk, P. M. Groffman, R. T. Holmes, P. A. Schwarz and R. D. Yanai. 2005. The
biogeochemistry of carbon at Hubbard Brook. Biogeochemistry 75(1):109-176.
Kaushal, S. S., P. M. Groffman, G. E. Likens, K. T. Belt, W. P. Stack, V. R. Kelly, L. E. Band and G. T.
Fisher. 2005. Increased salinization of fresh water in the northeastern United States. Proc. National
Academy of Sciences 102(38):13517-13520.
Kelly, V. R., G. M. Lovett, K. C. Weathers and G. E. Likens. 2005. Trends in atmospheric ammonium
concentrations in relation to atmospheric sulfate and local agriculture. Environmental Pollution
135:363-369.
Likens, G. E. 2005. A Biologist’s View of Liberal Education. In: The Liberal Education: Dead or
Alive? Conf., Dartmouth College.
Likens, G. E. 2005. Foreward. pp. v-vi. In: G. M. Lovett, C. G. Jones, M. G. Turner and K. C.
Weathers (eds.). Ecosystem Function in Heterogeneous Landscapes. Springer-Verlag New York Inc.
Likens, G. E. 2005. Foreword. pp. xi-xii. In: R. J. Naiman, H. Décamps and M. E. McClain (eds.).
Riparia: Ecology, Conservation, and Management of Streamside Communities. Elsevier Academic
Press, Inc.
Likens, G. E. 2005. Professor Robert G. Wetzel. SIL news 46:1-3.; Robert G. Wetzel, 1936-2005.
Limnology and Oceanography Bulletin 14(2):44-45.
Likens, G. E. 2005. Providing Limnological Leadership in Tomorrow's World. SIL Presidential
Address, Lahti, Finland. Verh. Internat. Verein. Limnol. 29(1):1-10.
Likens, G. E. and W. Lampert. 2005. In memoriam, Professor Robert G. Wetzel, 1936-2005. Arch.
Hydrobiol. 163(4):431-433.
Likens, G. E. and D. A. Pillard. 2005. Obituary, Frank A. Vertucci, 1956-2005. Limnol. Oceanogr.
Bulletin 14(4):83.
Likens, G. E., D. C. Buso and T. J. Butler. 2005. Long-term relationships between SO2 and NOX
emissions and SO42- and NO3- concentration in bulk deposition at the Hubbard Brook Experimental
Forest, New Hampshire. J. Environ. Monitoring 7(10):964-968.
Lovett, G. M., G. E. Likens, D. C. Buso, C. T. Driscoll and S. W. Bailey. 2005. The biogeochemistry ofchlorine at Hubbard Brook, New Hampshire, USA. Biogeochemistry 72:191-232.
Lowe, W. and G. E. Likens. 2005. Moving headwater streams to the head of the class. BioScience55(3):196-197.
Lowe, W. H., K. H. Nislow and G. E. Likens. 2005. Forest structure and stream salamander diets:
implications for terrestrial-aquatic connectivity. Verh. Internat. Verein. Limnol. 29(1):279-286.
Macneale, K. H., B. L. Peckarsky and G. E. Likens. 2005. Stable isotopes identify dispersal patterns ofstonefly populations living along stream corridors. Freshwater Biology 50:1117-1130.
Weathers, K. C., G. E. Likens, T. J. Butler and A. Elliott. 2005. Acid rain. (Chapter 117). In: W. Rom(ed.). Environmental and Occupational Medicine, Third Edition. Lippincott-Raven Publishers,
Philadelphia, 1998.
Campbell, J. L., J. W. Hornbeck, W. H. McDowell, G. E. Likens, D. C. Buso and J. B. Shanley. 2006.
Fluxes of dissolved organic carbon from eight forested watersheds in New England. (In Preparation)
Conley, D. J., G. E. Likens and D. C. Buso. 2006. Deforestation accelerates the land-ocean dissolved
silicate flux. (In Preparation)
Cosentino, B. J., W. H. Lowe and G. E. Likens. 2006. Demography and movement of the northern
spring salamander, Gyrinophilus porphyriticus, in four New Hampshire headwater streams. (InPreparation)
Eviner, V. T. and G. E. Likens. 2006. Effects of pathogens on terrestrial ecosystem function. In: R. S.
Ostfeld, F. Keesing and V. T. Eviner (eds.). Cary Conference XI: Infectious Disease Ecology: The
Effects of Ecosystems on Disease and of Disease on Ecosystems. Princeton University Press (In Press)
Galloway, J. N., W. C. Keene, G. E. Likens, F. Deviney , K. Mikkelsen and J. Moody. 2006.
Atmospheric wet deposition in remote regions: Benchmarks for environmental change. (InPreparation)

117

458. Galloway, J. N., G. E. Likens, B. J. Cosby and C. T. Driscoll. 2006. Comparison of longterm trends inprecipitation and stream chemistry of watersheds of Shenandoah National Park and the Hubbard Brook
Experimental Forest. (In Preparation)
459. Gliwicz, Z. M., M. Gophen, R. Gulati, D. Hamilton, B. Boss, S. Ostroumov, J. Padisak, B. Wehrli and
G. E. Likens. 2006. Memoriam: Professor Robert G. Wetzel. In: Ecological Studies, Hazards,
Solutions.
460. Groffman, P. M., M. C. Fisk, C. T. Driscoll, G. E. Likens, T. J. Fahey, C. Eagar and L. H. Pardo. 2006.
Calcium additions and microbial nitrogen cycle processes in a northern hardwood forest. Submitted to
Ecosystems..
461. Johnson, C. E., C. T. Driscoll, G. E. Likens, T. J. Fahey, T. G. Siccama and R. B. Romanowicz. 2006.
Calcium dynamics following whole-tree harvesting of a northern hardwood forest. (In Preparation)
462. Judd, K. E., G. E. Likens and P. M. Groffman. 2006. High nitrate retention during winter in soils of the
Hubbard Brook Experimental Forest. Ecosystems (In Press)
463. Lewis, G. P. and G. E. Likens. 2006. Changes in stream chemistry associated with insect defoliation in
an old-growth hemlock-hardwood forest. Forest Ecology and Management (In Press)
464. Lewis, G. P. and G. E. Likens. 2006. Potential contribution of insect defoliation to elevated nitrate loss
from a northern hardwood forest. (In Preparation)
465. Likens, G. E. 2006. A limnological introduction to Mirror Lake. Chapter 1. In: T. C. Winter and G. E.
Likens (eds.). Dynamics of Lake, Watershed and Atmospheric Linkages. (In Preparation)
466. Likens, G. E. 2006. Meromictic lake. McGraw-Hill Encyclopedia. pp. 679-681.
467. Likens, G. E. 2006. Lee Talbot’s ecosystem approach to conservation: Can it be sustained? In: R.
Stewart, R. B. Jonas, L. L. Rockwood and T. Dietz (eds.). Pathways to Sustainability: A Prospectus.
[Lee M. Talbot Festschrift] George Mason University, Fairfax, VA. (In Press)
468. Likens, G. E. and D. C. Buso. 2006. Variation in streamwater chemistry throughout the Hubbard Brook
Valley. Biogeochemistry 78:1-30.
469. Lovett, G. M., D. A. Burns, J. Jenkins, M. J. Mitchell, L. Rustad, J. B. Shanley, C. T. Driscoll, G. E.
Likens and R. Haeuber. 2006. Who needs environmental monitoring? Submitted to Frontiers in
Ecology and the Environment.
470. Lowe, W. H., G. E. Likens and B. J. Cosentino. 2006. Self-organization in streams: The relationshipbetween movement behavior and body condition in a headwater salamander. Freshwater Biology (InPress).
471. Lowe, W. H., G. E. Likens and M. E. Power. 2006. Linking scales in stream ecology. BioScience
56(7):591-597.
472. Lowe, W. H., G. E. Likens, M. A. McPeek and D. C. Buso. 2006. Linking direct and indirect data on
dispersal: Isolation by slope in a headwater stream salamander. Ecology 87(2):334-339.
473. Marino, R., F. Chan, R. W. Howarth, M. L. Pace and G. E. Likens. 2006. Ecological constraints onplanktonic nitrogen fixation in saline estuaries. I. Nutrient and trophic controls. Marine Ecology
Progress Series 309:25-39.
474. McLauchlan, K. K., J. M. Craine, W. W. Oswald, P. R. Leavitt and G. E. Likens. 2006. Ecosystem
recovery from land use has decreased forest nitrogen availability over the past century. Submitted to
Science.
475. Pace, M. L. and G. E. Likens. 2006. Hiding scientific findings is unfair to public. Editorial,
Poughkeepsie Journal, 2 March 2006.
476. Perron, R. L., G. E. Likens and D. C. Buso. 2006. Potassium in bulk precipitation versus wet deposition
during 1979-2001 at the Hubbard Brook Experimental Forest, NH (NADP Site NH02). (In Preparation)
477. Rosenberry, D. O., T. C. Winter, D. C. Buso and G. E. Likens. 2006. Comparisons of evaporation froma small New England lake as determined by 15 evaporation models. Submitted to Water Resour. Res.
478. Shortle, W. C., K. T. Smith, R. Minocha, G. B. Lawrence, K. A. Vogt, D. J. Vogt and G. E. Likens.
2006. Calcium as a dendrochemical marker of environmental change. (In Preparation)
479. Shortle, W. C., K. T, Smith, R. Minocha, G. E. Likens and J. F. Franklin. 2006. Comparative study ofdendrochemical patterns in southern beech from Tierra del Fuego and maple and birch from theAllegheny Plateau. (In Preparation)
480. Siccama, T. G., T. Fahey, C. E. Johnson, T. Sherry, E. Denny, E. B. Girdler, G. E. Likens and P.

118

481.
482.

483.
484.
485.
486.

487.

Schwarz. 2006. Population and biomass dynamics of trees in a northern hardwood forest at Hubbard
Brook. Canadian Journal of Forest Research (In Press)
Siccama, T. G., F. H. Bormann, G. E. Likens, T. Fahey, C. Johnson, S. Hamburg, C. Eagar and C.
Driscoll. 2006. Stand history, tree growth, biomass accretion and productivity. (In Preparation)
Stelzer, R. S. and G. E. Likens. 2006. Effects of sampling frequency on estimates of dissolved silica
export by streams: The role of hydrological variability and concentration-discharge relationships. Water
Resour. Res. 42: (In Press)
Tripler, C. E., S. S. Kaushal, G. E. Likens and M. T. Walter. 2006. Patterns in potassium dynamics inforest ecosystems. Ecology Letters 9: 451-466.
Wade, G. L., E. P. Weber, G. E. Likens and D. C. Buso. 2006. The application of process behavior
analysis to a watershed study. (In Preparation)
Warren, D. R., E. S. Bernhardt, R. O. Hall, Jr. and G. E. Likens. 2006. Forest age, woody debris, andnutrient dynamics in headwater streams of the White Mountains, NH. (In Preparation).
Weathers, K. C., G. E. Likens, T. J. Butler and A. Elliott. 2006. Acid rain. (Chapter 117). In: W. Rom(ed.). Environmental and Occupational Medicine, Third Edition. Lippincott-Raven Publishers,
Philadelphia.
Weber, E. P., G. E. Likens, D. C. Buso and G. L. Wade. 2006. A fine scale analysis of the long-term
biogeochemistry of Ca, NO3 and SO4 in a northern hardwood forest. (In Preparation)

119

Major Publications
Dr. F. Herbert Bormann
Books
1.
2.
3.
4.

5.
6.

7.
8.

Burch, W.R.,Jr., and FH. Bormann, Editors. 1976. Beyond Growth, Essays on Alternative Futures. Yale
University, School of Forestry and Environmental Studies Bulletin 88, New Haven, Connecticut. 228 pp.
Likens, G.E., F.H. Bormann, R.S. Pierce, J. S. Eaton, and N. M. Johnson. 1977. The Biogeochemistry of a
Northern Hardwood Forest Ecosystem. Springer-Verlag, New York. 146 pp.
Bormann, F. H., and G. E. Likens. 1979. Pattern and Process of a Forested System.
Springer-Verlag, New York. 253 pp. (Translated into Chinese).
Bormann, F. H., and G. P. Berlyn, Coordinators. 1981. Age and Growth rate of Tropical Trees: New
Directions for Research. Yale University, School of Forestry and, Environmental Studies Bulletin 94, New
Haven, Connecticut. 137 pp. (Translated into Spanish by Carmen Alicia de la Parra, Instituto Nacional deInvestigaciones, Sobre . Recursos Bioticos, Apartado Postal 63, Xalapa, Ver., Mexico, November, 1983).
Bormann, F. H., and S. R. Kellert. 1991. Ecology, economics, and ethics: the broken circle.
Yale University Press, New Haven, CT. 233 pp. Reprinted in paperback, 1994.
Bormann, F H.,. Diana Balmori, and Gordon Geballe. 1993. Redesigning the American lawn,a search for environmental harmony. Yale University Press, New Haven, CT. 166 pp.
Reprinted in paperback, 1995. Second edition published in 2001.
Likens, G.E., and FH. Bormann. 1995. Biogeochemistry of a forested ecosystem. Second
Edition. Springer-Verlag, N.Y. 162 pp. (Japanese translation)
In development. Bormann, F.H., J. Amthor, T. Fahey, and G. Whitney. 2000. Biotic
regulation of the structure and function of a forest ecosystem.

Articles1.
Bormann, FH. 1953. Factors determining the role of loblolly pine and sweetgum in early old-field
succession in the Piedmont of North Carolina. Ecol. Monogr. 23:339-358. George Mercer Award, ESA.
2.
Bormann, FH. 1953. The statistical efficiency of sample plot size and shape in forest ecology. Ecology
34(3):474-487.
3.
Bormann, FH. 1955. The primary leaf as an indicator of physiologic condition in shortleaf pine. For. Sci.
1(3):189-192.
4.
Bormann, F.H. and A.V. Beatty. 1955. Chromosome studies of plants from the Arctic slope of Alaska. 1.
Ranuncluaceae. Bull. Torrey Bot. Club 82(2):118-120.
5.
Buell, M.F and F.H. Bormann. 1955. Deciduous forests of Ponemah Point, Red Lake Indian Reservation,
Minnesota. Ecology 36(4):646-658.
6.
Bormann, FH. 1956. Ecological implications of changes in the photosynthetic response of Pinus taeda
seedlings during ontogeny. Ecology 37(1):70-75.
7.
Bormann, FH. 1956. Percentage light readings, their intensity-duration aspects, and their significance inestimating photosynthesis. Ecology 37 (3):473-476.
8.
Bormann, F.H. 1957. Moisture transfer between plants through intertwined root systems. Plant Physiol.
32(1):48-55.
9.
Bormann, FH. 1958. The relationships of ontogenic development and environmental modification tophotosynthesis in Pinus taeda seedlings. pp. 197-215. In: K. Thimann (ed.).Tree Physiology 10.
10. Bormann, F.H. and R.B. Platt. 1958. A disjunct stand of hemlock in the Georgia Piedmont. Ecology
39(1):16-23.
11. Bormann, FH., P.R. Shafer and D. Mulcahy. 1958. Fallout on the vegetation of New England during the1957 atom bomb test series. Ecology 39(2):376-378.
12. Bormann, F. H. 1958. The statistical efficiency of sample plot size and shape in forest ecology. Ecology
43(3):474-487.

120

13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.

33.
34.

35.
36.
37.
38.
39.

Bormann, F.H. and B.F. Graham, Jr. 1959. The occurrence of natural root grafting in eastern white pine,
Pinus strobus L., and its ecological implications. Ecology 40(4):677-691.
Bormann, F.H. 1960. Individuality in forest trees. Dartmouth Alumni Mag. Feb:43-45.
Bormann, F.H. and B.P. Graham, Jr. 1960. Translocation of silvicides through root grafts. ]. For.
58(5):402-403.
Bormann, F.H. 1961. Intraspecific root grafting and the survival of eastern white pine stumps. For. Sci.
7(3):247-256.
Bormann, F.H. 1961. Intraspecific root grafts and transport. Rec. Adv. Bot. 2: 1309-1311.
Bormann, F.H. and- B.P. Graham. 1961. A study of intraspecific root grafts in white pine, Pinus strobus L.,
by means of radioisotopes and dyes. Rec. Adv. Bot. Sec. 12:1375-1377.
Bormann, F.H. 1962. Intraspecific root grafting and noncompetitive relationships between forest trees. pp.
237-246. In: Proc. Symp. on Tree Growth, Tucson, Arizona. Ronald Press.
Bormann, F.H. and T.T. Koslowski. 1962. Measurements of tree ring growth with dial-gauge dendrometersand vernier tree ring bands. Ecology 43(2):289-294.
Lyon, c.]. and F.H. Bormann (eds.). 1962. Natural areas of New Hampshire suitable for ecologicalresearch. Dept. of Biol. Sci. Publ. No.2.
Bormann, F.H. 1963. Ontogenetic relationships of the primary leaf on Pinus taeda L. and P. echinata Mill.
Bull. Torrey Bot. Club 90(5):320-332.
Myers, O., Jr. and F.H. Bormann. 1963. Phenotypic variation in Abies balsamiJa in response to altitudinaland geographic gradients. Ecology 44(3):429-436.
Bormann, F.H. and M.F. Buell. 1964. Old-age stand of hemlock-northern hardwood forest in central
Vermont. Bull. Torrey Bot. Club 91(6):451-465.
Bormann, F.H. 1965. Changes in the growth pattern of white pine trees undergoing suppression. Ecology
46(3):269-277.
Bormann, F.H.1966. The need for a federal system of natural areas for scientific research, BioScience
16:585-586. (editorial)
Bormann, F.H. 1966. The structure, function, and ecological significance of root grafts in Pinus strobus L.
Ecol. Monogr. 36:1-26.
Bormann, F.H. 1966. Testimony before the committee on interior and insular affairs, U.S. Senate, 89th
Congress, 2nd Session on S.2282. pp. 72-76.
Graham, B.F., Jr. and F.H. Bormann. 1966. Natural root grafts. Bot. Rev. 32(3):255-292.
Bormann, F.H. and G.E. Likens. 1967. Nutrient cycling. Science 155(3761):424~429.
Likens, G.E., F.H. Bormann, N.M. Johnson and R.S. Pierce. 1967. The calcium magnesium, potassium andsodium budgets for a small forested ecosystem. Ecology 48(5):772-785.
Bormann, F.H., G.E. Likens, D.W. Fisher and R.S. Pierce. 1968. Nutrient loss accelerated by clear-cuttingof a forest ecosystem. Science 159(3817):882-884; Also, pp. 187~195. In: Proc. Symp. on Primary
Productivity and Mineral Cycling in Natural Ecosystems.
Bormann, F.H. and G.K. Voigt. 1968. The School of Forestry and the environment crisis. Yale Forest
School News 56(2)}6.
Fisher, D.W., A.W. Gambell, G.E. Likens and F.H. Bormann. 1968. Atmospheric contributions to water
quality of streams in the Hubbard Brook Experimental Forest, New Hampshire. Water Resour. Res.
4(5):1115-1126.
Johnson, N.M., G.E. Likens, F.H. Bormann and R.S. Pierce. 1968. Rate of chemical weathering of silicate
minerals in New Hampshire. Geochem. Cosmoch. Acta 32:531-545.
Smith, W.H., F.H. Bormann and G.E. Likens. 1968. Response of chemoautotropic nitrifiers to forest
cutting. Soil Science 106(6):471- 473..
Bormann, F.H. 1969. A holistic approach to nutrient cycling problems in plant communities. Symp. in Terrestrial Plant Ecology, Antigonish, Nova Scotia (1966). Nova Scotia Museum Publ., Halifax. pp. 149-165.
Bormann, F.H. 1969. The ecosystem concept-the necessary basis for multiple use. pp. 21-26. In: Proc.
Conf. on Multiple - Use of Southern Forests. Pine Mountain, Georgia.
Bormann, F.H. 1969. Testimony on H.R. 6750 "To amend the Fish and Wildlife Coordination Act. toprovide for the establishment of a Council on Environmental Quality and for other purposes." June 26,1969
Congressional Record.

121

40.

41.

42.
43.
44.

45.
46.
47.
48.
49.
50.
51.
52.
53.
54.

55.

56.
57.
58.
59.
60.
61.

62.
63.
64.

122

Bormann, F.H. and G.E. Likens. 1969. A watershed approach to problems of nutrient cycling in forest
ecosystems. pp. 2303-2306. In: Proc. 6th World Forestry Congress, Vol. 2, Tech. Comm. III. Madrid,
Spain.
Bormann, F.H. and G.E. Likens. 1969. The watershed-ecosystem concept and studies of nutrient cycles.
pp. 49-79. In: G.M. VanDyne (ed.). The Ecosystems Concept in Natural Resource Management. Chapter
IV, Academic Press, Inc.; New York.
Bormann, F.H., G.E. Likens and ].S. Eaton. 1969. Biotic regulation of particulate and solution losses froma forest ecosystem. BioScience 19(7):600-610.
Eaton, J .S., G.E. Likens and F.H. Bormann. 1969. Use of membrane f1lters in gravimetric analyses ofparticulate matter in natural waters. Water Resour. Res. 5(5):1151-1156.
Johnson, N.M., G.E. Likens, F.H. Bormann, D.W. Fisher and R.S. Pierce. 1969.A working model for thevariation in stream water chemistry at the Hubbard Brook Experimental Forest, New Hampshire. Water
Resour. Res. 5(6):1353-1363.
Likens, G.E., F.H. Bormann and N.M. Johnson. 1969. Nitrification: importance to nutrient losses from acutover forested ecosystem. Science 163(3872):1205-1206.
Bormann, F.H. 1970. The ecosystem concept-necessary basis for land use. SAF New England section.
March 12, 1970.
Bormann, F.H. 1970. Subtraction by multiplication: population, technology and the diminished man. Yale
Alumni Magazine, May:38-42.
Bormann, F.H. 1970. Testimony on Water Quality Legislation, U.S. Senate. May 26, 1970 Congressional
Record.
Bormann, F.H., and G.K. Voigt. 1970. Introduction. In: H.W. Helfrich, Jr. (ed.). The Environmental Crisis.
Yale U. Press, New Haven, CT. pp. ix-x.
Bormann, F.H. and G.E. Likens. 1970. The nutrient cycles of an ecosystem. Sci. Amer.223(4):92-101.
Bormann, F.H., T.G. Siccama, G.E. Likens and R.H. Whittaker. 1970. The Hubbard' Brook Ecosystem
Study: composition and dynamics of the tree stratum. Ecol. Monogr.40(4):373-388.
Ledig, F.T., F.H. Bormann and K. Wenger. 1970. Distribution of dry matter growth between shoot and rootin loblolly pine seedlings. Botanical Gazette 131:349-459.
Likens, G.E. and F.H. Bormann. 1970. Chemical analyses of plant tissues from the Hubbard Brook
Ecosystem in New Hampshire. Yale Univ. School of Forestry Bull. 79, 25 pp.
Likens, G.E., F.H. Bormann, N.M. Johnson, D.W. Fisher and R.S. Pierce. 1970. Effects of forest cutting
and herbicide treatment on nutrient budgets in the Hubbard Brook watershed-ecosystem. Ecol. Monogr.
40(1):23-47.
Pierce, R.S., J.W. Hornbeck, G.E.Likens and F.H. Bormann. 1970. Effects of elimination of vegetation on
stream water quantity and quality. pp. 311-328. In: Internat. Symp. on Results of Research on
Representative and Experimental Basins. Wellington, New Zealand. Internat. Assoc. Sci. Hydrol.
Siccama, T.G., F.H. Bormann and G.E. Likens. 1970. The Hubbard Brook Ecosystem Study: productivity,
nutrients and phytosociology of the herbaceous layer. Ecol. Monogr. 40(4):389-402.
Bormann, F.H. 1971. Comments on the National Environmental Laboratory Bill S. 3410. pp. 335-339. In:
National Environmental Laboratories, Serial No. 92-3. U.S. Govt. Printing Office.
Bormann, F.H. 1971. U.S. Senate, Subcommittee on Air and Water Pollution on the Committee on Public
Works. National Environmental Laboratories. pp. 309-321.
Bormann, F.H., M.F. Cushman, T. Dominski, T.G. Siccama and D.G. Sprugel. 1971. The Ecological
Register for the New England States. Ecol. Soc. Amer.
Bormann, F.H. and G.E. Likens. 1971. The ecosystem concept and the rational management of natural
reso~ces. Yale Sci. Mag. 45(7):2-8.
Likens, G.E., F.H. Bormann, R.S. Pierce and D.W. Fisher. 1971. Nutrient-hydrologic cycle interaction insmall forested watershed-ecosystems. pp. 553-563. In: P. . Duvigneaud (ed.). Proc. Brussels Symp. on
Productivity of Forest Ecosystems (1969). UNESCO, Paris.
Bormann, F.H. 1971. Diminishing Man. Ecology Today pp. 11-16.
Bormann, F.H.1972. The American dream: can it evolve? pp. 105-117. In: J.G. Holway and J.G. New(eds.). Search for a Quality of Life, Challenge of the 1970's. State Univ. College of Oneonta, New York.
Bormann, F.H., P. Sears, G.M. Woodwell. 1970. Yale Reports. Sunday, Apri112, 1970-#550.

65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.

82.
83.
84.
85.
86.

87.
88.

89.

90.

Bormann, F.H. 1972. Unlimited growth: growing, growing, gone? BioScience 22(12):706-709.
Bormann, F.H. 1972. Urgently needed: A nationwide appraisal of the growth problem. In: Environmental
Affairs 2(2), The Environmental Law Center, Boston College Law School, Brighton, Massachusetts.
Gosz, J.R., G.E. Likens and F.H. Bormann. 1972. Nutrient content of litter fall on the Hubbard Brook
Experimental Forest, New Hampshire. Ecology 53(5):769-784.
Likens, G.E. and F.H. Bormann. 1972. Biogeochemical cycles. The Science Teacher 39(4):15-20.
Likens, G.E. and F.H. Bormann. 1972. Nutrient cycling in ecosystems. pp. 25-67. In: J. Wiens (ed.).
Ecosystem Structure and Function. Oregon State Univ. Press, Corvallis.
Likens, G.E., F.H. Bormann and N.M. Johnson. 1972: Acid rain. Environment 14(2):33-40.
Marks, P.L. and F.H. Bormann. 1972. Revegetation following forest cutting: mechanisms for return tosteady state nutrient cycling. Science 176:914-915.
Pierce, R.S., CW. Martin, CC Reeves, G.E. Likens and F.H. Bormann. 1972. Nutrient loss fromclearcuttings in New Hampshire. pp. 285-295. In: Symp. on Watersheds in Trans., Ft. Collins, Colorado.
Bormann, F.H. 1973. The far environment and its impact on the family. In: Proc. Colloquium on the
Family and the Environment, Univ. of Connecticut, Storrs.
Eaton, ].S., G.E. Likens and F.H. Bormann. 1973. Throughfall and stemflow chemistry in a northernhardwood forest. J. Eco1. 61(2):495-508.
Bormann, F.H., G.E. Likens. 1973. Report for the Site Visit by the National Science Foundation to the
Hubbard Brook Ecosystem Study.
Gosz, J.R., G.E. Likens and F.H. Bormann. 1973. Nutrient release from decomposing leaf and branch litterin the Hubbard Brook Forest, New Hampshire. Eco1. Monogr. 43(2):173-191.
Art, H.W., F.H. Bormann, G.K. Voigt and G.M. Woodwell. 1974. Barrier Island Forest ecosystem: role ofmeteorologic nutrient inputs. Science 184:60-62.
Bormann, F.H. 1974. Acid rain and the environment future. Environ. Conser., p. 270.
Bormann, F.H., G.E. Likens, T.G. Siccama, R.S. Pierce and ].S. Eaton. 1974. The export of nutrients andrecovery of stable conditions following deforestation at Hubbard Brook. Eco1. Monogr.44(3):255-277.
Likens, G.E. and F.H. Bormann. 1974. Acid rain: a serious regional environmental problem. Science
184(4142):1176-1179.
Likens, G.E. and F.H. Bormann. 1974. Effects of forest clearing on the northern hardwood forest
ecosystem and its biogeochemistry. pp. 330~335. In: Proc. First Internat. Congr. Ecology, Sept. 1974,
Centre Agric. Pub1. Doc. Wageningen, The Hague.
Likens, G.E. and F.H. Bormann. 1974. Linkages between terrestrial and aquatic ecosystems. BioScience
24(8):447-456.
Whittaker, R.H., F.H. Bormann, G.E. Likens and T.G. Siccama. 1974. The Hubbard Brook Ecosystem
Study: forest biomass and production. Ecol. Monogr. 44(2):233-254.
Wood, T. and F.H. Bormann. 1974. The effects of an artificial acid mist upon the growth of Betula
alleghaniensis. Britt. Environ. Pollut. 7:259-268.
Bormann, F.H. and G.E. Likens. 1975. The role of nature in the urbanized landscape. Natural History.
Hornbeck, J.W., G.E. Likens, R.S. Pierce and F.H. Bormann. 1975. Strip cutting as a. means of protectingsite streamflow quality when clearcutting northern hardwoods. pp. 209-229. In: B. Bernier and C.H.
Winget (eds.). Proe. 4th No. Amer. Forest Soils Conf. on Forest Soils and Forest Land Management,
August 1973. Quebec, Canada.
Likens, G.E. and F.H. Bormann. 1975. Acidity in rainwater: Has an explanation been presented? Science
188:957-958.
Likens, G.E. and F.H. Bormann. 1975. An experimental approach in New England landscapes. pp. 7-29.
In: A.D. Hasler (ed.). Proc. INTECOL Symp. on Coupling of Land Water Systems, 1971. Leningrad.
Springer-Verlag, New York.
Likens, G.E., F.H. Bormann,].S. Eaton, R.S. Pierce and N.M. Johnson. 1975. Hydrogen ion input to the
Hubbard Brook Experimental Forest, New Hampshire during the last decade. In: Proc. First. Internat.
Symp. on Acid Precipitation and the Forest Ecosystem, May 1975; U.S.D.A. Forest Service. Columbus,
Ohio.
Likens, G.E., N.M. Johnson, J.N. Galloway and F.H. Bormann. 1975. Acid precipitation: strong and weakacids. Science 194:643-645.

123

91.
92.
93.
94.
95.

96.
97.
98.
99.
100.
101.
102.
103.
104.
105.
106.

107.
108.

109.

110.

111.

112.
113.

124

Wood, T. and F.H. Bormann. 1975. Increases in foliar leaching caused by acidification of an artificial mist.
Ambio 4(4):169-171.
Gosz, J.R., G.E. Likens and F.H. Bormann. 1976. Organic matter and nutrient dynamics of the forest floor
in the Hubbard Brook forest. Oecologia 22:305-320.
Bormann, F.H. 1976. An inseparable linkage: conservation of natural ecosystems and the conservation offossil energy. BioScience 26:754-760.
Muller, R.N. and F.H. Bormann. 1976. Role of Erythroconium americanum ker. by energy flow andnutrient dynamics of a northern hardwood forest ecosystem. Science 193:1126-1128.
Wood, T. and F.H. Bormann. 1976. Short-term effects of a simulated acid rain upon the growth andnutrient relations of Pinus strobus L. pp. 815-825. In:L.S. Dochinger and T.A. Seliga (eds.). Proc. The FirstInternat. Symp. on Acid Precipitation and the Forest Ecosystem. U.S.D.A. Forest Service General Tech.
Report NE-23; ALSO Water, Air and Soil Pollution 7:479-488 (1977).
Testimony before John J. Currey, Hearing Examiner, Department of Environmental Protection, Conn.
January 27, 1976.
Bormann, F.H., G.E. Likens and J. Melillo. 1977. Nitrogen budget for an aggrading northern hardwood
ecosystem. Science 196:981-983.
Bormann, F.H. and G.E. Likens. 1977. The fresh air - clean water exchange. Natural History 86(9):62-71.
Likens, G.E., F.H. Bormann, R.S. Pierce,].S. Eaton and N.M. Johnson. 1977. Biogeochemistry of aForested Ecosystem. Springer-Verlag New York Inc. 146 pp.
Bormann, F.H. 1978. Earthcare and temperate forests. In: Earthcare: Global Protection of Natural Areas.
Ed. by E.A. Schofield. Westview Press. Eaton,].S.,
G.E. Likens and F.H. Bormann. 1978. The input of gaseous and particulate sulfur to a forest ecosystem.
Tellus 30:546-551.
Gosz, J.R.,R.T. Holmes, G.E. Likens and F.H. Bormann. 1978. The flow of energy in a forest ecosystem.
Sci. Amer. 238(3):92-102.
.
Likens, G.E., F.H. Bormann, R.S. Pierce and W.A. Reiners. 1978. Recovery of a deforested ecosystem.
.Science 199(4328):492-496.
Mahall, B.E. and F.H. Bormann. 1978. A quantitative description of the vegetative phenology of herbs in anorthern hardwood forest. Bot. Gaz. 139:467-481.
Bormann, F.H. and G.E.Likens. 1979. Catastrophic disturbance and the steady state in northern hardwood
forests. Amer. Sci. 67(6):660-669.
Likens, G.E. and F.H. Bormann. 1979. The role of watershed and airshed in lake metabolism. pp. 95-211.
In: W. Rodhe, G.E. Likens and C. Serruya (eds.). Lake Metabolism and Management. Papers Emanatingfrom the Jubilee Symposium of Uppsala University, Sweden. Arch. Hydrobiol. Beih. Ergebn. Limnol. 13.
Whittaker, R.H., G.E. Likens, F.H. Bormann,].S. Eaton and T.G. Siccama. 1979. The Hubbard Brook
Ecosystem Study: forest nutrient cycling and element behavior. Ecology 60(1):203-220.
Eaton, J.S., G.E. Likens and F.H. Bormann. 1980. Wet and dry deposition of sulfur at Hubbard Brook. pp.
69-75. In: T.C. Hutchinson and M. Havas (eds.). Effect of Acid Precipitation on Terrestrial Ecosystems.
NATO Conf. Series 1: Ecology 4. Plenum Publishing Corp. .
Likens, G.E., F.H. Bormann and].S. Eaton. 1980. Variations in precipitation and streamwater chemistry at
the Hubbard Brook Experimental Forest during 1964 to 1977. pp. 443-464. In: T.C. Hutchinson and M.
Havas. (eds.). Effects of Acid Precipitation on Terrestrial Ecosystems. NATO Conference Series 1:
Ecology 4. Plenum Publishing Corp.
Melillo, J.M. and F.H. Bormann. 1980. Reorganization of a terrestrial ecosystem following a perturbation.
pp. 28-32. In: O.L. Loucks (ed.). The Study of Species Transients, Their Characteristics and Significancefor Natural Resource Systems. Report from the Workshop "Analysis of Transient Events in Ecosystems."
The Institute of Ecology, Indianapolis, Indiana.
Likens, G.E., F.H. Bormann and N.M. Johnson. 1980. Interactions between major biogeochemical cycles:
terrestrial cycles. In: G.E. Likens (ed.). Interactions Between Major Biogeochemical Cycles. SCOPE IVthGeneral Assembly, Stockholm, Sweden. John Wiley & Sons Ltd.
Bormann, F.H. 1981. Ecological implications. In: Mergen, F. (ed.). Tropical forests: Utilization andConservation. Yale School of Forestry and Environmental Studies, New Haven, CT. 199 pp.
Bormann, F.H. and W.H. Smith. 1981. Effects of air pollution on forest ecosystems. pp. 308-318. In:

114.

115.
116.

117.
118.
119.
120.
121.
122.
123.
124.
125.
126.

127.
128.

129.
130.

131.
132.
133.

134.

135.
136.

137.

Energy and the Fate of Ecosystems. Supporting paper No.8. Report of Resource Information, Impacts
Resource Group Risk and Impact Panel of Community Study of Nuclear and Alternative Energy Systems.
National Research Council, National Academy Press, Washington, D.C.
Likens, G.E., F.H. Bormann and N.M. Johnson. 1981. Interactions between major biogeochemical cycles
in terrestrial ecosystems. pp. 93-112. In: G.E. Likens (ed.). Some Perspectives of the Major
Biogeochemical Cycles. SCOPE 17. John Wiley & Sons, Ltd., Chichester.
Sprugel, D.G. and F.H. Bormann. 1981. Natural disturbance and the steady state in high-altitude balsam fir
forests. Science 211(4479): 390-393.
Bormann, F.H. 1981. Introduction. In: H.A. Mooney, T.M. Bonnickson, N.L.
Christensen, J.E. Lotan and W.A. Reiners (eds.). Fire Regimes and Ecosystem. Properties. U.S.D.A. Forest
Service General Technical Report WO-26.
Bormann, F.H. 1981. An earth day call for responsibility. Yale Daily News. New Haven, CT. April 22.
Bormann, F.H. 1981. A review of "Gaia: a new look at life on earth" by J.E. Lovelock. Ecology 62:502.
Bormann, F.H. 1982. Air pollution stress and energy policy. In: New England Prospects: Critical Choices
in a Time of Change. C. Reidel (ed.). Univ. Press of New England. Hanover, N.H. pp. 85-140.
Bormann, F.H. 1982. The vulnerable landscape: the threat to New England. Yale Alumni Magazine andJournal XLV(6):10-16. .
Ryan, D.F. and F.H. Bormann. 1982. Nutrient resorption with ecosystem development in northernhardwood forests. BioScience. 32:29-32.
Bormann, F.H. 1982. The effects of air pollution on the New England landscape, Part 1. AMEIO
11(4):188-194.
Bormann, F.H. 1982. The effects of air pollution on the New England landscape, Part II. AMBIO
11(6):338-346.
Bormann, F.H. 1983. The landscape: air pollution stress and energy policy. ESPER Journal No. I:37-40.
Amthor, J.S. and F.H. Bormann. 1983. Productivity of perennial ryegrass as a function of precipitation
acidity. Env. Pollution 32: 137-145.
Bormann, F.H. 1984. Factors confounding evaluation of air pollution stress on forests: pollution input andecosystem complexity. In: Symp. by Commission of the European Communities, "Acid Deposition, a
Challenge for Europe." Karlsruhe, FRG. September 1983.
Likens, G.E., F.H. Bormann, R.S. Pierce, ].S. Eaton, and R.E. Munn. 1984. Long-term trends inprecipitation chemistry at Hubbard Brook, New Hampshire. Atmos. Environ. 18(12):2641-2647.
Munn, R.E., G.E. Likens, B. Weisman,].W. Hornbeck, C.W. Martin, and F.H. Bormann. 1984. A
meteorological analysis of the precipitation chemistry event samples at Hubbard Brook, New Hampshire.
Atmos. Environ. 18(12):2775-2779.
Wood, T., F.H. Bormann, and G.K. Voigt. 1984. Phosphorus cycling in a northern hardwood forest:
biological and chemical control. Science 223:391-393.
Bormann, F.H. 1985. Testimony to the Subcommittee on General Oversite, Northwest Power, and Forest
Management; Committee on Interior and Insular Affairs; U.S. House of Representatives. Washington, DC.
4 pp. July 16, 1985.
Bormann, F.H. 1985. Air pollution and forests: an ecosystem perspective. BioScience 35(7):434-441.
Bormann, F.H. 1985. A last walk in Princeton. Princeton Alumni Weekly. p. 56.
Bormann, F.H. and G.E. Likens. 1985. Air and watershed management and the aquatic ecosystem. pp. 436444. In: G.E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and Its Environment.
Springer-Verlag New York Inc.
Bormann, R.E., F.H. Bormann, and G.E. Likens. 1985. Catastrophic disturbance and regional land use. pp.
65-72. In: G.B. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and Its
Environment. Springer-Verlag New York Inc.
Likens, G.E. and F.H. Bormann. 1985. An ecosystem approach. pp. 1-8. In: G.E. Likens (ed.) An
Ecosystem Approach to Aquatic Ecology: Mirror Lake and Its Environment. Springer-Verlag, NY Inc.
Likens, G.E., F.H. Bormann, R.S. Pierce, and ].S. Eaton. 1985. The Hubbard Brook Valley. pp. 9-39. In:
G.E. Likens (ed.). An Ecosystem Approach to Aquatic Ecology: Mirror Lake and Its Environment.
Springer-Verlag New York Inc.
Martin, C. Wayne, R.S. Pierce, G.E. Likens, F.H. Bormann. 1986. Clearcutting affects stream chemistry in

125

138.

139.
140.
141.
142.
143.

144.
145.
146.
147.

148.

149.
150.

151.

152.
153.

154.

155.

156.
157.

126

the White Mountains of New Hampshire. USDA Forest Service, Northeastern Forest Experiment Station
Research Paper NE-579, Durham, N.H. 12 pp.
Bormann, F.H. 1986. Lessons from Hubbard Brook. In: E. Keller, S. Cooper and De Vries (eds). Proc. of
the Chaparral Ecosystems Research Meeting. Santa Barbara, California. California Water Resources
Center, Univ. of California, Davis. Report #62. 7 pp.
Bowden, W.B. and F.H. Bormann. 1986. Transport and loss of nitrous oxide in soil water after forest clearcutting. Science 233:867-869.
Hornbeck, J.W., C.W. Martin, R.S. Pierce, F.H. Bormann, G.E. Likens and ].S. Eaton. 1986. Clearcutting
northern hardwoods: effects on hydrologic and nutrient ion budgets. Forest Science 32(3)667-686.
Wang, Deane, D.F. Karnosky and F.H. Bormann. 1986. Effects of ambient ozone on the productivity ofPopulus tremuloides Michx. grown under field conditions. Can. J. For. Res. 16:47-55.
Wang, Deane, F.H. Bormann and D.F. Karnosky. 1986. Regional tree growth reductions due to ambient
ozone: evidence from field experiments. Environ. Sci. Technol. 20(11)1122-1125.
Weathers, K.C., G.E. Likens, F.H. Bormann, J.S. Eaton, W.B. Bowden, J.L. Andersen, D.A. Cass, J.N.
Galloway, W.C. Keene, K.D. Kimball, P. Huth and D. Smiley. 1986. A regional acidic cloud/fog water
event in the eastern United States. Nature 319(6055):657-658.
Bormann, F.H. 1987. Landscape ecology and air pollution. In: M.G. Turner (ed). Landscape Heterogeneity
and Disturbance. Springer-Verlag, New York, pp. 37-57.
Hedin, L.O., G.E. Likens and F.H. Bormann. 1987. Decrease in precipitation acidity resulting fromdecreased SO42- deposition. Nature 325:244-246.
Bormann, F.H. and G.E. Likens. 1987. Changing perspectives on air-pollution stress. BioScience37(6):370.
Hornbeck, ].W., CW. Martin, R.S. Pierce, F.H. Bormann, G.E. Likens, and ].S. Eaton. 1987. The northernhardwood forest ecosystem: ten years of recovery from clearcutting. U.S.D.A. Forest Service, Northeastern
Forest Experiment Station, NERP-596. 30 pp.
Bormann, F.H., W.B. Bowden, R.S. Pierce, S.P. Hamburg, R.C Ingersoll, G.E. Likens, and G.K. Voigt.
1987. The Hubbard Brook sandbox experiment. In: W.R. Jordan III, M.E. Gilpin and].D. Aber (eds.).
Restoration Ecology: A Synthetic Approach to Ecological Research. Cambridge University Press. NewYork.
Wang, D., and F.H. Bormann. 1987. Letter to the Editor. Environment, Science and Technology 21:607.
Weathers, K. C, G. E. Likens, F. H. Bormann, S. H. Bicknell, B. T. Bormann, B. C Daube, Jr., J. S. Eaton,
J. N. Galloway, W. C Keene, K. D. Kimball, W. H. McDowell, TG. Siccama, D. Smiley, R. A. Tarrant.
1988. Cloud water chemistry from ten sites in North America. Environmental Science and Technology
22(9):1018-1026.
Weathers, K. C, G. E. Likens, F. H. Bormann, J. S. Eaton, K. D. Kimball, J. N. .Galloway, T G. Siccama,and D. Smiley. 1988. Chemical concentrations in cloud water from four sites in the eastern U.S. In: Acid
Deposition at High Elevation Sites. M. H. Unsworth and D. Fowler (eds.). Kluwer Academic Publishers,
pp. 345-357.
Hughes, J.W., T.J. Fahey and F.H. Bormann. 1988. Population persistence and demographics of awoodland herb: Aster acuminatus, Michx. Amer. Jour. Bot. 75:1057-1064
Bormann, F.H. 1989. Research and educational goals for the Duke University School of Forestry andEnvironmental Studies. In: M.L. Matthews (ed.). Education and Research in natural resources: The next 50
years, Proceedings of the 50th Anniversary Symposium, School of Forestry & Environmental Studies,
Duke University, Durham, NC October 28, 1989.
Driscoll, CT., G.E. Likens, L.O. Hedin, J.S. Eaton, and F.H. Bormann. 1989. Changes in the chemistry of
surface waters: twenty-fIve-year results at the Hubbard Brook Experimental Forest, NH. Environmental
Science & Technology 23(2):137-143. .
Pletscher, D. H., F. H. Bormann, and R. S. Miller. 1989. Importance of deer compared to other vertebrates
in nutrient cycling and energy flow in a northern hardwood ecosystem. American Midland Naturalist
121:302-311.
Driscoll, CT., G.E. Likens, L.O. Hedin and F.H. Bormann. 1989. A. reply to CW. Chen and L.E. Gomez,
letter to the Editor, 'Surface Water Chemistry'. Environ. Sci. Tech. 23(7):754-755.
Bormann, F.H. 1990. The global environmental deficit. Viewpoint. BioScience 40 (2):74.

158. Amthor ,J.S., D,S. Gill, and F.H. Bormann. 1990. Autumnal leaf conductance and apparent photosyn-thesisby saplings and sprouts in a recently disturbed northern hardwood forest. Oecologia 84:93-98.
159. Likens, G.E., F.H. Bormann, C.T. Driscoll, L.O. Hedin and J.S. Eaton. 1990. Dry deposition of sulfur inthe Hubbard Brook Experimental Forest. Tellus. 42B, 319-329.
160. Lugo, A.E., D. Wang, and F.H. Bormann. 1990. A comparative analysis of biomass production in fivetropical tree species. J. Ecology and Forest Management 31: 153-166.
161. Bormann, F. H. 1991. Air pollution and temperate forests: creeping degradation? In: G.W. Woodwell (ed).
Earth in Transition: Patterns and Processes of Biotic Impoverishment. Cambridge University Press, New
York. pp. 25-44.
162. Bormann, F.H. and S.R. Kellert. 1991. Preface: The global environmental deficit. In: Ecology, Economics,
Ethics: The Broken Circle. F.H. Bormann and S.R. Kellert. Eds. Yale University Press.
163. Kellert, S.R. and F.H. Bormann. 1991." Closing the circle: weaving strands among ecology, economics,
and ethics. In: Ecology, Economics, Ethics: The Broken Circle. F.H. Bormann and S. R. Kellert (eds). Yale
University Press.
164. Bormann, F.H., K.R. Smith and B.T. Bormann. 1991. Earth to Hearth: a microcomputer model forcomparing biofuel systems. Biomass and Energy. 1:17-34.
165. Duggin, J.A, G.K. Voigt and F.H. Bormann. 1991. The response of autotrophic and heterophic nitrification
to clear cutting northern hardwood forest. Soil Biology and Biochemistry. 23:779-787.
166. Wang, D., F.H. Bormann, A Lugo and R. Bowden. 1991. Comparison of nutrient-use efficiency in fivetropical tree taxa. Forest Ecology and Management. 46:1-21.
167. F.H. Bormann. 1991. Contributions to five radio lectures. CJRT. FM. Open College, Toronto.
168. Pierce, R.S., F.H. Bormann and G.E. Likens. 1990. Ed. P.F. Folliet and D.P. Guertin.
Proceedings of the Workshop, Forest Hydrological Resources in China and Analytical Assessment. Harbin,
People's Republic of China. August, 1987.
169. Bormann, B.T., F.H. Bormann, W.B. Bowden, S.P. Hamburg, D. Wang, M.C. Snyder, C.Y. Lee, and R.C.
Ingersoll. 1992. Rapid N2 fixation in pines, alder, and locust: evidence from the sandbox ecosystem study.
Ecology 74:583-598.
170. Bormann, F.H. 1993. Foreword to the dictionary of ecology and environmental science edited by H.A. Art.
Henry Holt and Co.
171. Wang, D., M.C. Snyder and F.H. Bormann. 1993. Potential errors in measuring nitrogen content of soils
low in nitrogen. Soil Sci. Soc. Am. J. 57:1533-1536.
172. Bormann, F.H. 1994. Earth threatened by environmental debt. New Haven Register, April 22, 1994.
173. Siccama, TG., S.P. Hamburg, M.A. Arthur, R.D. Yanai, F. H. Bormann, and G.E. Likens. 1994.
Corrections of allometric equations and plant tissue chemistry for Hubbard Brook Experimental Forest.
Ecology 75(1):246-248.
174. Wang, E.X., F.B. Bormann, and G. Benoit. 1995. Evidence of complete retention of atmospheric lead innorthern hardwood ecosystems. Environment, Science and Technology 29:735-39.
175. Bormann, F.H. 1995. Confronting the environmental debt. A guest essay in Living in the Environment by
G. Tyler Miller. Wadsworth Publishing. Belmont, CA.
176. Bormann, F.H. 1996. Ecology: A Personal History. Ann. Rev. of Energy and Environment 21:1-29.
177. Gill, D. S., J. S. Amthor, and F. H. Bormann. 1998. Leaf phenology, and photosynthesis of saplings andshrubs in the understory of a northern hardwood forest. Tree Physiology 18:281-289.
178. Bormann, B.T, D. Wang, and F.H. Bormann, et al. 1998. Rapid plantinduced weathering in an aggrading
experimental ecosystem. Biogeochemistry 43:129-155.
179. Bormann, F.H. 2000. On respect for Nature NRCC News 13. Autumn, pp. 4-5.
180. Bormann, B.T, C.K. Keller, D. Wang, and F.H. Bormann. 2002. Lessons from the Sand Box: is
unexplained nitrogen real? Ecosystem 5: 727-733.
181. Bormann, F.Herbert (with G.E. Likens). 2003. Environmental challenges in the twenty-first century andour respect of nature. Blue Planet Prize 2003. Commemorative Lecture. The Asahi Glass Foundation.
182. Bormann, FH. 2005. The end of reductionism? Frontiers in Ecology and Environment 3(9): p.472.
183. Bormann, F.H. 2006. Gas prices and land abandonment. Frontiers in Ecology and the Environment 4(3):pp.122-123.

127