bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobility and distribution of zinc forms in columns of an acid, a neutral, and a calcareous soil treated with three organic zinc complexes under laboratory conditions
Authors: Novillo J. , Obrador A. , López-Valdivia L. M. , Alvarez J. M.
Published: September 2002

Three liquid zinc (Zn) fertilisers were mixed with the upper 1.5 cm of columns representing 3 different soil profiles: Aquic Haploxeralf, of an acid nature and with hydromorphic problems; Calcic Haploxeralf, of a neutral nature; and Typic Xerorthents, of a calcareous nature. They were periodically irrigated for 60 days. Most of the applied Zn remained in the top of the soil when it was added as Zn-lignosulfonate plus EDTA or Zn-2-hydroxy-1,2,3-propanotricarboxilate. When Zn-EDTA plus fulvic and humic acid fertiliser was applied, Zn migrated and distributed throughout the soil resulting in losses of Zn by leaching of 2.29% in acidic soil, 27.36% in neutral soil, and 10.5% in calcareous soil of the Zn applied. The 3 fertilisers produce sufficient concentrations of the bioavailable Zn forms in the Ap horizons (DTPA and Mehlich-3 extractable Zn) for the cultivation of different plants. In the calcareous soil, which contained free CaCO3, the amount of Zn extracted by Mehlich-3 was higher than in soils with no free CaCO3. Distribution of Zn in the soil was studied at the beginning and end of the experiment by means of one sequential fractionation and showed that added Zn remained in more labile fractions for uptake by plants in the acid and neutral soils when compared with the control. When Zn was added to calcareous soil, no amount of Zn was detected in the water-soluble plus exchangeable fraction at the end of experiment for any Zn fertiliser source.
Measurement and prediction of permethrin persistence in six Malaysian agricultural soils
Authors: Ismail B. S. , Kailasam Kalithasan
Published: September 2002

The effect of soil types, soil temperature, and soil moisture content on the degradation of permethrin was studied under controlled greenhouse conditions. Six soils were used in the study: Soil 1 (Teringkap series), Soil 2 (Ringlet series), Soil 3 (Teringkap 2), Soil 4 (Teringkap 3), Soil 5 (Gunung Berinchang), and Soil 6 (Lating series). Observed data showed that permethrin was more persistent in Soil 1 (23.3 days) and less persistent in Soil 5 (16.7 days). Similarly, the degradation rate coefficient (k) was greater in Soil 5 than Soil 1. The half-life and the dissipation patterns of permethrin between the observed and predicted data were not much different in all 6 soils studied, even though the predicted data were slightly higher. The half-life of permethrin in Soil 6 decreased as the temperature increased from 20°C (36.1 days) to 35°C (13.9 days). The degradation rate coefficient increased as the temperature increased. The predicted data derived from the model showed greater values than the observed data. The half-life of permethrin in Soil 6 decreased as the soil moisture increased from 30% (26.8 days) to 80% (20.1 days). The dissipation rate was not very different between the predicted and the observed data at 80% field capacity and at the temperature of 35°C, and it consequently became closer when the incubation period was prolonged.
Methods for assessing mine site rehabilitation design for erosion impact
Authors: Evans Kenneth G.
Published: September 2002

Erosion of rehabilitated mines may result in landform instability, which in
turn may result in exposure of encapsulated contaminants, elevated sediment
delivery at catchment outlets, and subsequent degradation of downstream water
quality. Rehabilitation design can be assessed using erosion and hydrology
models calibrated to mine site conditions. Incision rates in containment
structures can be quantified using 3-dimensional landform evolution simulation
techniques. Sediment delivery at catchment outlets for various landform
amelioration techniques can be predicted using process-based and empirical
erosion-prediction models and sediment delivery ratios. The predicted sediment
delivery can be used to estimate an average annual stream sediment load that
can, in turn, be used to assess water quality impacts. Application of these
techniques is demonstrated through a case study applied to a proposed
rehabilitation design option for the Energy Resources of Australia Ltd (ERA)
Ranger Mine in the Northern Territory of Australia.
Use of laboratory-scale rill and interill erodibility measurements for the prediction of hillslope-scale erosion on rehabilitated coal mine soils and overburdens
Authors: Sheridan G. J. , So H. B. , Loch R. J. , Pocknee C. , Walker C. M.
Published: September 2002

Prediction of hillslope-scale soil erosion traditionally involves extensive
data collection from field plots under natural rainfall, or from field
rainfall simulation programs. Recognising the high costs and inconvenience
associated with field-based studies, a method was developed and tested for
predicting hillslope-scale soil erosion from laboratory-scale measurements of
erodibility. A laboratory tilting flume and rainfall simulator were used to
determine rill and interill erodibility coefficients for 32 soils and
overburdens from Queensland open-cut coal mines. Predicted sediment delivery
rates based on laboratory determinations of erodibility were tested against
field measurements of erosion from 12-m-long plots under simulated rainfall at
100 mm/h on slopes ranging from 5% to 30%. Regression
analysis demonstrated a strong relationship between predicted and measured
sediment delivery rates, giving an
r2 value of up to 0.74, depending
on the particular modeling approach used. These results demonstrate that soil
losses due to the combined processes of rill and interill erosion at the
hillslope scale can successfully be predicted from laboratory-scale
measurements of erodibility, provided a suitable methodology and modelling
approach is adopted. The success of this approach will greatly reduce the cost
and effort required for prediction of hillslope scale soil erosion.
Soil stripping and replacement for the rehabilitation of bauxite-mined land at Weipa. I. Initial changes to soil organic matter and related parameters
Authors: Schwenke G. D. , Mulligan D. R. , Bell L. C.
Published: September 2002

At Weipa, in Queensland, Australia, sown tree and shrub species sometimes fail
to establish on bauxite-mined land, possibly because surface-soil organic
matter declines during soil stripping and replacement. We devised 2 field
experiments to investigate the links between soil rehabilitation operations,
organic matter decline, and revegetation failure.
Experiment 1 compared two routinely practiced operations, dual-strip (DS) and
stockpile soil, with double-pass (DP), an alternative method, and subsoil
only, an occasional result of the DS operation. Other treatments included
variations in stripping-time, ripping-time, fertiliser rate, and cultivation.
Dilution of topsoil with subsoil, low-grade bauxite, and ironstone accounted
for the 46% decline of surface-soil (0–10 cm) organic C in DS
compared with pre-strip soil. In contrast, organic C in the surface-soil
(0–10 cm) of DP plots (25.0 t/ha) closely resembled the pre-strip
area (28.6 t/ha). However, profile (0–60 cm) organic C did not
differ between DS (91.5 t/ha), DP (107 t/ha), and pre-strip soil (89.9
t/ha). Eighteen months after plots were sown with native vegetation,
surface-soil (0–10 cm) organic C had declined by an average of 9%
across all plots.
In Experiment 2, we measured the potential for post-rehabilitation decline of
organic matter in hand-stripped and replaced soil columns that simulated the
DS operation. Soils were incubated in situ without
organic inputs. After 1 year’s incubation, organic C had declined by up
to 26% and microbial biomass C by up to 61%.
The difference in organic C decline between vegetated replaced soils (Expt 1)
and bare replaced soils (Expt 2) showed that organic inputs affect levels of
organic matter more than soil disturbance. Where topsoil was replaced at the
top of the profile (DP) and not ploughed, inputs from volunteer native grasses
balanced oxidation losses and organic C levels did not decline.
Impact of vegetative cover and slope on runoff, erosion, and water quality for field plots on a range of soil and spoil materials on central Queensland coal mines
Authors: Carroll C. , Merton L. , Burger P.
Published: September 2002

In 1993, a field study commenced to determine the impact of vegetative cover
and slope on runoff, erosion, and water quality at 3 open-cut coal mine sites.
Runoff, sediment, and water quality were measured on 0.01-ha field plots from
3 slope gradients (10, 20, 30%), with pasture and tree treatments
imposed on soil and spoil material, and 2 soil and spoil plots left bare.
The greatest soil erosion occurred before pasture cover established, when a
large surface area of soil (>0.5 plot area) was exposed to rainfall and
overland flow. Once buffel grass (Cenchrus ciliaris)
colonised soil plots, there were negligible differences in soil erosion
between slope gradients. On spoil, Rhodes grass
(Chloris gayana) reduced in situ
soluble salt content, and reduced runoff electrical conductivity to levels
measured in surrounding creeks. Where spoil crusted there was poor vegetative
growth and unacceptably large runoff and erosion rates throughout the study.
Field measured mobile water fraction for soils of contrasting texture
Authors: Okom A. E. A. , White R. E. , Heng L. K.
Published: September 2002

For the purpose of modeling solute transport, soil water has often been simply
divided into an essentially mobile fraction, q m , which
is active in solute transport, and an apparently immobile fraction, q
im . Distinction between q m and q
im was sought using the disc permeameter technique. This
study examines unsaturated estimates of mobile water content at suction heads,
h, of 20, 40, 80, and 120 mm for several soils ranging
in texture from sand to clay. Following infiltration of 35 mm depth of 0.01 M
KBr into initially dry soils, soil samples were collected from below the base
of the disc permeameter and analysed for tracer concentrations which enabled
partitioning of mobile and immobile water. Hydraulic conductivity and
sorptivity were also derived from the infiltration data. The results show the
expected non-linearity of hydraulic conductivity and sorptivity with suction.
The mobile water expressed as a fraction, f, of the
volumetric water content q (f = q
m / q ) was generally found to range from 0.7 to
0.95, with an average of 0.85. The exception was one site for which
f was ª 0.50. These values of
f are comparable to those derived from leaching studies
reported in the literature. An important finding of this work is that within
the range of suctions measured, the mobile fraction was independent of
suction. A possible explanation for this observation is that the soil
capillary forces were dominant during the time scale of the experiment and
therefore rapidly drew the invading solution. This finding could have
important implications for fertiliser application. Furthermore, this result
suggests that the assumption of a negligible solute transfer coefficient, a ,
between the mobile and immobile domains may be valid within the time scale of
this method of measuring the mobile water content.
Evaluation and development of hydraulic conductivity pedotransfer functions for Australian soil
Authors: Minasny Budiman , McBratney Alex. B.
Published: September 2002

Pedotransfer functions (PTFs) for predicting saturated hydraulic conductivity
(Ks) were evaluated using
published Australian soil data sets. Eight published PTFs were evaluated.
Generally, published PTFs provide a satisfactory estimation of
Ks depending on the spatial scale
and accuracy of prediction. Several PTFs were developed in this study,
including the power function of effective porosity, multiple linear
regression, fractal model, and artificial neural networks. Different methods
for estimating the fractal dimension of particle-size distributions showed no
significant differences in predicting
Ks . The simplest model for
estimating fractal dimension from the log–log plot of particle-size
distribution is therefore recommended. The data set was also stratified into 3
broad classes of texture: sandy, loamy, and clayey. Stratification of PTFs
based on textural class showed small improvements in estimation. The published
PTF of Dane and Puckett (1994) Proc. Int. Workshop (Univ. of California:
Riverside, CA) gives the best prediction for sandy soil; the PTF of Cosby
et al. (1984)
Water Resources Research 20,
682–90 gives the best production for loamy soil; and the PTF of Schaap
et al. (1998)
Soil Science Society of America Journal
62, 847–55 gives the best prediction for clayey
soil. The data set used comprised different field and laboratory measurements
over large areas, and limited predictive variables were available. The PTFs
developed here may predict adequately in large areas (residuals =
10–20 mm/h), but for site-specific applications, local calibration
is needed.
Pig effluent-P application can increase the risk of P transport: two case studies
Authors: Redding Matt R.
Published: September 2002

Land application of piggery effluent (containing urine, faeces, water, and
wasted feed) is under close scrutiny as a potential source of water resource
contamination with phosphorus (P). This paper investigates 2 case studies of
the impact of long-term piggery effluent-P application to soil.
A Natrustalf (Sodosol) at P1 has received a net load of 3700 kg effluent
P/ha over 19 years. The Haplustalf (Dermosol) selected (P2) has received a
net load of 310 000 kg P/ha over 30 years. Total, bicarbonate-extractable,
and soluble P forms were determined throughout the soil profiles for paired
(irrigated and unirrigated) sites at P1 and P2, as well as P sorption and
desorption characteristics.
Surface bicarbonate (P B , 0–0.05 m depth) and
dilute CaCl 2 -extractable molybdate-reactive P (P
C ) have been significantly elevated by effluent
irrigation (P1: P B unirrigated 231, irrigated 2906; P
C unirrigated 0.030.00, irrigated 23.90.2; P2: P
B unirrigated 7248, irrigated 39501960; P
C unirrigated 0.70.0, irrigated 443287 mg P/kg;
means.d.). Phosphorus enrichment to 1.5 m, detected as P
B , was observed at P2. Elevated concentrations of CaCl
2 -extractable organic P forms (P
OC ; estimated by non-molybdate reactive P in
centrifuged supernatants) were observed from the soil surface of P1 to a depth
of 0.4 m. Despite the extent of effluent application at both of these sites,
only P1 displayed evidence of significant accumulation of P
OC .
The increase in surface soil total P (0–0.05 m depth) due to effluent
irrigation was much greater than laboratory P sorption (>25 times for P1;
>57 times for P2) for a comparable range of final solution concentrations
(desorption extracts range 1–5 mg P/L for P1 and 50–80 mg
P/L for P2). Precipitation of sparingly soluble P phases was evidenced in
the soils of the P2 effluent application area.
Salt source for dryland salinity - evidence from an upland catchment on the Southern Tablelands of New South Wales
Authors: Acworth R. I. , Jankowski J.
Published: September 2002

A detailed study involving drilling, geophysics, hydrogeochemistry, and
groundwater monitoring over a 10-year period has been carried out at a small
catchment south-east of Yass on the Southern Tablelands of New South Wales to
investigate the source of salt causing dryland salinity. The catchment is
within 2 km of the top of a regional groundwater and surface water divide and
remains substantially tree covered. The investigations have found a highly
heterogeneous distribution of salt, most of which is associated with swelling
clay. Dispersion of this clay causes the surface features commonly associated
with dryland salinity.
There is no hydrogeochemical evidence to suggest evaporative or transpirative
concentration of salt in the groundwater. The short flow path from the top of
the catchment cannot provide a significant source of salt from bedrock
weathering. An alternative model of salt accumulation is proposed with the
salt imported into the catchment with silt during dust storms in the arid and
windy conditions during the last glacial. The management implications of this
model of salt distribution and the associated dryland salinity development are
discussed.
Detection and growth of an Alaskan forest fire using GOES-9 3.9 µm imagery
Authors: Hufford Gary L. , Kelley Herbert L. , Moore Raymond K. , Cotterman Jeffrey S.
Published: September 2002

The utility of the new GOES-9 satellite 3.9 µm channel to monitor
wildfires and their subsequent changes in growth and intensity in Alaska is
examined. The June, 1996 Miller’s Reach forest fire is presented as a
case study. Eighteen hours of sequential imagery coincident to the initiation
and early stages of the fire are analyzed for hot spots. The dramatic response
of the 3.9 µm channel to sub-pixel hot spots and the ability to access
the data every 15 minutes makes the channel an effective tool to support
forest fire management on wildfires in high latitudes to at least 61°N. In
the case of Miller’s Reach, the fire was detected when it was less than
200 hectares in size. Changes in fire growth and intensity were also observed.
An automated technique for decision makers which classifies hot spots without
requiring image interpretation is proposed.
Temperature-time curves at the soil surface in maquis summer fires
Authors: Molina M.J. , Llinares J.V.
Published: September 2002

Many summer fires in Valencia are enhanced by the abundance of maquis.
Nevertheless, fire field studies on the soil temperature–time curves
under summer conditions with controlled amount and structure of fuel are
scarce. Experimental summer fires were conducted to analyse the influence of
the fuel load and the fuel structure on the soil temperature-time profiles.
The increase of fuel load from 2 to 4 kg m–2
increased the net radiant heat per unit area (5691 to 11263 kJ
m–2), the total duration of heat (190 to 396 min)
and the duration of temperatures greater than 100ºC (19.8 to 35.9 min)
whereas the peak temperature increased 100ºC (from 416ºC to
516ºC).
Variations of fuel height from 1.5 to 0.75 m and bulk density from 2 to 4 kg
m–3 respectively, increased net radiant heat per
unit area, Hp/a (6510 to 10
444 kJ m–2),
ttotal (219 to 375 min), and
t>100ºC (9.7 to 36. 1 min)
whereas Tmax increased 40ºC
(446 to 486ºC).
At plot scale, fire intensity and severity will increase with the fuel load.
At plant scale, more degradation will occur in the soil patches with higher
bulk density, mainly because an increased duration of high temperatures in
soil. Fuel amount and structure are then key factors in maquis fires since
they will determine the post-fire patchiness of soil conditions and plant
recovery.
Fire history differences in adjacent Jeffrey pine and upper montane forests in the eastern Sierra Nevada
Authors: Stephens Scott L.
Published: September 2002

Fire history and forest structural characteristics of adjacent Jeffrey pine
(Pinus jeffreyi) and upper montane forests was
investigated in the eastern Sierra Nevada at the University of California
Valentine Natural Reserve. Jeffrey pine forests had lower canopy cover, higher
amounts of fine fuels, and higher shrub cover when compared to upper montane
forest that were dominated by red fir (Abies magnifica).
Fire dates were determined using standard dendrochronolgy techniques from
fire-scarred Jeffrey pine, lodgepole pine
(Pinus contorta var. murrayana),
red f ir, and western white pine (Pinus monticola)
trees, snags, stumps, and downed logs. Fires were recorded from 1745 to 1889
and mean fire return intervals were 9 and 24.7 years for the Jeffrey pine and
upper montane forest types, respectively. The median fire return interval was
9.0 years for Jeffrey pine and 24.0 years for upper montane forests.
Significant differences were found in mean fire intervals and fire history
distributions between the two similarly sized fire history plots even though
they were only separated by approximately 100 m. This study suggests that fire
regimes can vary over very fine spatial scales. Differences in fire regimes
are likely due to differences in fuel beds and fire behavior.
Estimating live fine fuels moisture content using meteorologically-based indices
Authors: Viegas D. X. , Piñol J. , Viegas M. T. , Ogaya R.
Published: September 2002

Field measurements of moisture content of several fine fuels (shrub vegetation
and live foliage) were performed in Central Portugal and in Catalunya (NE
Spain) for 1–10 years. Seasonal and interannual variation of live fine
fuels of several species in two regions of the Iberian Peninsula are analysed.
The species were grouped in three sets according to their relatively high,
intermediate or low seasonal variability. Meteorological data from nearby
stations were collected in each study area and used in the evaluation of some
indicators of fuel moisture that are used in the Canadian Forest Fire Danger
Rating System, namely the Drought Code (DC). It was found that in the summer
season the slow response of live fine fuel moisture content (LFFMC) to
meteorological conditions, namely to precipitation, was well described by the
DC. Empirical correlations between LFFMC and DC for each species and site are
proposed.
Changing fuel management strategies - The challenge of meeting new information and analysis needs
Authors: Conard Susan G. , Hartzell Timothy , Hilbruner Michael W. , Zimmerman G. Thomas
Published: September 2002

This paper was presented at the conference ‘Integrating spatial technologies and ecological principles for a new age in fire management’, Boise, Idaho, USA, June 1999
‘The earth, born in fire, baptized by lightning since before life"s beginning, has been and is a fire planet.’
E.V. Komarek
Attitudes and policies concerning wildland fire, fire use, and fire management
have changed greatly since early European settlers arrived in North America.
Active suppression of wildfires accelerated early in the 20th Century, and
areas burned dropped dramatically. In recent years, burned areas and cost of
fires have begun to increase, in part due to fuel buildups resulting from fire
suppression. The importance of fire as an ecosystem process is also being
increasingly recognized. These factors are leading to changes in Federal
agency fire and fuels management policies, including increased emphasis on use
of prescribed fire and other treatments to reduce fuel loads and fire hazard.
Changing fire management strategies have highlighted the need for better
information and improved risk analysis techniques for setting regional and
national priorities, and for monitoring and evaluating the ecological,
economic, and social effects and tradeoffs of fuel management treatments and
wildfires. The US Department of Interior and USDA Forest Service began the
Joint Fire Science Program in 1998 to provide a sound scientific basis for
implementing and evaluating fuel management activities. Development of remote
sensing and GIS tools will play a key role in enabling land managers to
evaluate hazards, monitor changes, and reduce risks to the environment and the
public from wildland fires.
Accuracy assessment and validation of remotely sensed and other spatial information
Authors: Congalton Russell G.
Published: September 2002

This paper was presented at the conference ‘Integrating spatial technologies and ecological principles for a new age in fire management’, Boise, Idaho, USA, June 1999
Today, validation or accuracy assessment is an integral component of most
mapping projects incorporating remotely sensed data. Other spatial information
may not be so stringently evaluated, but at least requires meta-data that
documents how the information was generated. This emphasis on data quality was
not always the case. In the 1970s only a few brave scientists and researchers
dared ask the question, ‘How good is this map derived from Landsat MSS
imagery?’ In the 1980s, the use of the error matrix became a common tool
for representing the accuracy of individual map categories. By the 1990s, most
maps derived from remotely sensed imagery were required to meet some minimum
accuracy standard. A similar progression can be outlined for other spatial
information. However, this progression is about 5 years behind the validation
of remotely sensed data. This paper presents a series of steps moving towards
better assessment and validation of spatial information and asks the reader to
evaluate where they are in this series and to move forward.
Mapping fire regimes across time and space: Understanding coarse and fine-scale fire patterns
Authors: Morgan Penelope , Hardy Colin C. , Swetnam Thomas W. , Rollins Matthew G. , Long Donald G.
Published: September 2002

This paper was presented at the conference ‘Integrating spatial technologies and ecological principles for a new age in fire management’, Boise, Idaho, USA, June 1999
Maps of fire frequency, severity, size, and pattern are useful for
strategically planning fire and natural resource management, assessing risk
and ecological conditions, illustrating change in disturbance regimes through
time, identifying knowledge gaps, and learning how climate, topography,
vegetation, and land use influence fire regimes. We review and compare
alternative data sources and approaches for mapping fire regimes at national,
regional, and local spatial scales. Fire regimes, defined here as the nature
of fires occurring over an extended period of time, are closely related to
local site productivity and topography, but climate variability entrains fire
regimes at regional to national scales. In response to fire exclusion
policies, land use, and invasion of exotic plants over the last century, fire
regimes have changed greatly, especially in dry forests, woodlands, and
grasslands. Comparing among and within geographic regions, and across time, is
a powerful way to understand the factors determining and constraining fire
patterns. Assembling spatial databases of fire information using consistent
protocols and standards will aid comparison between studies, and speed and
strengthen analyses. Combining multiple types of data will increase the power
and reliability of interpretations. Testing hypotheses about relationships
between fire, climate, vegetation, land use, and topography will help to
identify what determines fire regimes at multiple scales.
Fire, climate change, carbon and fuel management in the Canadian boreal forest
Authors: Amiro B.D. , Stocks B.J. , Alexander M.E. , Flannigan M.D. , Wotton B.M.
Published: September 2002

This paper was presented at the conference ‘Integrating spatial technologies and ecological principles for a new age in fire management’, Boise, Idaho, USA, June 1999
Fire is the dominant stand-renewing disturbance through much of the Canadian
boreal forest, with large high-intensity crown fires being common. From 1 to 3
million ha have burned on average during the past 80 years, with 6 years in
the past two decades experiencing more than 4 million ha burned. A large-fire
database that maps forest fires greater than 200 ha in area in Canada is being
developed to catalogue historical fires. However, analyses using a regional
climate model suggest that a changing climate caused by increasing greenhouse
gases may alter fire weather, contributing to an increased area burned in the
future. Direct carbon emissions from fire (combustion) are estimated to
average 27 Tg carbon year–1 for 1959–1999 in
Canada. Post-fire decomposition may be of a similar magnitude, and the
regenerating forest has a different carbon sink strength. Measurements
indicate that there is a net carbon release (source) by the forest immediately
after the fire before vegetation is re-established. Daytime downward carbon
fluxes over a burned forest take 1–3 decades to recover to those of a
mature forest, but the annual carbon balance has not yet been measured. There
is a potential positive feedback to global climate change, with anthropogenic
greenhouse gases stimulating fire activity through weather changes, with fire
releasing more carbon while the regenerating forest is a smaller carbon sink.
However, changes in fuel type need to be considered in this scenario since
fire spreads more slowly through younger deciduous forests. Proactive fuel
management is evaluated as a potential mechanism to reduce area burned.
However, it is difficult to envisage that such treatments could be employed
successfully at the national scale, at least over the next few decades,
because of the large scale of treatments required and ecological issues
related to forest fragmentation and biodiversity.
Impacts of wildfire on soil hydrological properties of steep sagebrush-steppe rangeland
Authors: Pierson F.B. , Carlson D.H. , Spaeth K.E.
Published: September 2002

In late August 1996, a wildfire swept across the sagebrush-dominated foothills above Boise, Idaho. Fire impacts on infiltration and inter-rill erosion were examined 1 year following the fire with simulated rainfall. Densely vegetated north-facing slopes were compared with sparsely vegetated south-facing slopes under both burned (moderate and high severity) and unburned conditions. Both fire severity and slope aspect strongly influenced the impact of fire on infiltration capacity and soil erodibility. South-facing slopes had the least infiltration and the greatest rates of erosion following the fire. Infiltration rate was significantly less and cumulative sediment yield was significantly greater on severely burned south slopes as compared with those experiencing only moderate burn severity. Fire severity had little effect on infiltration and erosion of north-facing slopes. Despite differences in final infiltration rates, runoff from plots of all treatment combinations (burned and unburned slopes) began within 2-4 min following the start of simulated rainfall. Post-fire microtopography (surface roughness, dependent on pre-fire plant community) and associated ground cover appear to be important determinants of the potential for increased runoff and interrill erosion under conditions of dry antecedent soil moisture on these steep rangelands.
Prefire heterogeneity, fire severity, and early postfire plant reestablishment in subalpine forests of Yellowstone National Park, Wyoming
Authors: Turner Monica G. , Romme William H. , Gardner Robert H.
Published: September 2002

The 1988 fires in Yellowstone National Park providedan opportunity to study
effects of a large infrequent disturbance on a natural community. This study
addressed two questions: (1) How does prefire heterogeneity of the landscape
affect postfire patterns of fire severity? and (2) How do postfire patterns of
burn severity influence plant reestablishment? At three sites, 100 sampling
points were distributed regularly in a 1-km x 1-km grid and sampled annually
from 1989 to 1992. Information was recorded on fire severity (damage to trees,
depth of ash and soil charring, and percent mineral soil exposed); pre-fire
forest structure (forest successional stage; tree density; tree species; tree
size; and evidence of pre-fire disturbance by mountain pine beetle
[Dendroctonus ponderosae Hopk.] or
mistletoe [Arceuthobium americanum Nutt. ex
Engelm.]); post-fire percent cover of graminoids, forbs, and low
shrubs; number of lodgepole pine (Pinus contorta var.
latifolia Engelm.) seedlings; and general topographic
characteristics (slope and aspect). Fire severity was influenced by
successional stage, with older stands more likely to be in the more severe
burn class, and by tree diameter, with tree damage diminishing with tree size.
Prefire bark beetle and mistletoe damage also influenced fire severity; severe
prefire damage increased the likelihood of crown fire, but intermediate
prefire damage reduced the likelihood of crown fire. Fire severity was not
influenced by slope, aspect, or tree density. Postfire percent vegetative
cover and density of lodgepole pine seedlings varied with burn severity. In
lightly burned areas, percent cover returned to unburned levels by 1991. In
severely burned areas, total percent cover was about half that of unburned
areas by 1992, and shrub cover remained reduced. Recruitment of lodgepole pine
seedlings was greatest during the second postfire year and in severe-surface
burns rather than in crown fires. Continued monitoring of vegetation dynamics
in Yellowstone’s burned forests will contribute to our understanding of
successional processes following a disturbance that was exceptional in its
size and severity.
Modeling fire interval data from the American southwest with the Weibull distribution
Authors: Grissino-Mayer Henri D.
Published: September 2002

In this study, the Weibull distribution is tested as a possible model for fire
interval data derived from dendrochronologically-dated fire scars from four
sites in the American Southwest. Two- and three-parameter Weibull
distributions were fit to fire interval data sets, and additional statistical
descriptors based on the Weibull were derived to improve our understanding of
the range of variability in presettlement fire regimes. The three-parameter
models failed to provide improved fits versus the more parsimonious
two-parameter models, indicating the Weibull shift parameter may be
superfluous for Southwestern fire regimes. The Weibull Modal Interval (MOI)
was a superior overall measure of central tendency, and appears to identify a
common underlying structure in Southwestern fire regimes independent of
habitat type and environmental gradients. Unusually short and long fire
intervals were identified by the lower and upper exceedance intervals (LEI and
UEI) and the Maximum Hazard Interval (MHI) based on the Weibull hazard
function. Model statistics were nearly identical between two pairs of sites
that were 260 kilometers distant that differed in topography, vegetation, and
land-use history. However, differences were observed between sites only 10
kilometers apart, suggesting the influence of local factors (e.g., topography
and substrate) over regional influences (e.g., climate). Although the Weibull
models helped quantify the historical range of variability in presettlement
fire regimes, ecological interpretations of the Weibull parameters proved
difficult.
Home range of stoats (Mustela erminea) in podocarp forest, south Westland, New Zealand: implications for a control strategy
Authors: Miller Craig , Elliot Mike , Alterio Nic
Published: September 2002

The home range of stoats (Mustela erminea) was
determined as part of a programme to protect Okarito brown kiwi chicks
(Apteryx australis) ‘Okarito’, from
predation. Twenty-seven stoats were fitted with radio-transmitters and tracked
in two podocarp (Podocarpaceae) forests, in south Westland, New Zealand, from
July 1997 to May 1998. Home-range area was determined for 19 animals by
minimum convex polygons and restricted-edge polygons, and core areas were
determined by hierarchical cluster analysis. The mean home ranges of males
across all seasons calculated by minimum convex polygon (210 28 ha ( s.e.))
and restricted-edge polygon (176 29 ha) were significantly larger than those
of females across all seasons (89 14 ha and 82 12 ha). The mean home range of
males calculated by minimum convex polygon during the breeding season (256 38
ha) was significantly larger than the mean home range pooled across the
non-breeding seasons (149 16 ha), whereas that calculated by restricted-edge
polygon was not significantly different. The mean home range of females during
the breeding season was not significantly different from that in the
non-breeding seasons when estimated by either method. Overlap of home ranges
was observed within and between sexes in all seasons, with the greatest
proportion of home range overlap being male–female. The mean home range
of females in spring and summer is used to guide the spacing of control
stations.
Breeding biology, reproductive success and survival of blue-breasted fairy-wrens in fragmented habitat in the Western Australian wheatbelt
Authors: Brooker Michael , Brooker Lesley
Published: September 2002

We studied blue-breasted fairy-wrens,
Malurus pulcherrimus, over a 6-year period in 17
differently sized remnants in a highly fragmented agricultural landscape at
Wyalkatchem, Western Australia. The wrens lived in groups of 2–5 adults,
comprising one breeding female, her consort and up to three helpers (usually
adult male offspring). Groups lived in permanent year-round territories
averaging 2.2 ha. Data from 536 nests indicated that breeding extends from
August to December in good seasons but from August to October in years of
drought. Overall, the average clutch size was 2.91 (median 3), although in the
driest year of the study it was 2.31 (median 2). Individual nest success was
low, with a mean of 1.02 fledglings produced per clutch. However, the wrens
made 1.87 nesting attempts per year, thereby raising the annual reproductive
output to 1.63 fledglings per group and 0.49 potential breeders per group.
There was a positive relationship between nest predation and remnant size and
no difference in the predation rate of nests in the largest remnant depending
on how far they were located from the edge of the remnant. Nest parasitism by
Horsfield"s bronze-cuckoo, Chrysococcyx basalis,
was also positively related to remnant size. Consequently, annual reproductive
success was higher in the 13 small remnants (2.16 fledglings per group per
year), compared with 3 medium-sized remnants (1.94) and the largest remnant
(1.32). Annual adult survival was 63.9% for breeding females and
67.2% for senior males. Survival was positively related to remnant size
for adults, but not for fledglings. The annual survival of adults in small
remnants was 54.5%, compared with 64.9% in medium-sized remnants
and 68.6% in the largest remnant. It is suggested that, in order to
conserve sedentary species living in fragmented habitats, we should try to
retain the whole range of patch sizes that remain, even if some (or most) of
the vegetation mosaic has been removed and even if some remnants are extremely
small.
Effects of fragmented habitat and fire on the distribution and ecology of the swamp antechinus (Antechinus minimus maritimus) in the eastern Otways, Victoria
Authors: Wilson B. A. , Aberton J. G. , Reichl T.
Published: September 2002

This study investigated the distribution, habitat and population dynamics of
the swamp antechinus (Antechinus minimus maritimus) in
the eastern Otway Ranges. The species has a restricted, disjunct distribution
and has been recorded at 25 sites between 1969 and 1999. All sites were
located within 7 km of the coast, occurred at altitudes up to 80 m above sea
level and within 10 m of a gully. Analysis of landscape site variables
identified sun index as being significant in determination of the probability
of occurrence of A. minimus. The presence of
A. minimus is negatively associated with sun index,
occuring at sites that have a southerly aspect and gentle slope.
A. minimus was located in a range of structural
vegetation including Open Forest, Low Woodland, Shrubland and Hummock
Grassland and a number of floristic groups, some characterised by high
frequencies of sclerophyll shrubs, others by high frequencies of
Pteridium esculentum, hummock grasses and herbaceous
species. A. minimus occurs in fragmented, small
populations with maximum population densities of 1.1–18
ha–1. Populations at inland sites became extinct
after the 1983 wildfire which burnt 41 000 ha. These sites have not been
recolonised since, while on the coast the species did not re-establish until
1993–97. One population that is restricted to a narrow coastal strip of
habitat is characterised by high levels of transient animals. The species is
subject to extinction in the region due to habitat fragmentation, coastal
developments and fire. Management actions to secure the present populations
and ensure long-term survival of the species in the area are required and
include implementation of appropriate fire regimes, prevention of habitat
fragmentation, revegetation of habitat, and establishment of corridor habitat.
A review of methods to estimate the abundance of terrestrial carnivores using field signs and observation
Authors: Wilson Gavin J. , Delahay Richard J.
Published: September 2002

This paper reviews field methods for estimating and monitoring the abundance
of terrestrial carnivores that do not involve capture. Effective methods of
monitoring abundance are important tools for the management and conservation
of many species. The development of methods for carnivores presents particular
challenges, as they are often secretive and widely dispersed. Nevertheless, a
variety of approaches based on direct observations and quantification of field
signs have been employed. These techniques are described in relation to
carnivore ecology and resource implications, and the advantages and
deficiencies of each are discussed with reference to case studies.
Bait palatability influences the caching behaviour of the red fox (Vulpes vulpes)
Authors: van Polanen Petel A. Marjolein , Marks Clive A. , Morgan David G.
Published: September 2002

In a free-choice experiment conducted in a series of pen trials, the influence
of food preference on caching behaviour by the red fox
(Vulpes vulpes) was investigated for three unpoisoned
bait types: deep-fried beef liver (DFL), dried deep-fried beef liver (DDFL)
and a commercial bait (Foxoff®). Although some variation in individual
preferences for the DDFL and Foxoff was observed, all of the foxes in the pen
trials preferred the DFL (P < 0.01) and all cached it
least often (P < 0.01). Field trials then compared
the uptake, consumption and incidence of caching for the most preferred (DFL)
and least preferred (Foxoff) bait types. Radio-transmitters were inserted into
unpoisoned Foxoff and DFL baits and a free choice of either was provided at
bait stations at three independent sites. A clock module recorded the precise
time that each bait was taken from the bait station. The fate of each bait (it
could either be eaten, cached or remain in situ) was
recorded daily and baits were replaced for five consecutive nights. There was
no difference in the rate of uptake for the two baits (P
> 0.05) and, despite some variation between the sites, DFL was the most
often eaten (P < 0.001) and Foxoff the most often
cached (P < 0.001). These data strongly suggest that
a highly palatable bait will increase the likelihood of rapid consumption of
baits and reduce the incidence of caching. This is likely to increase the
cost-effectiveness of baiting and limit the potential for nontarget impacts
due to the movement of baits. The high degree of concordance between the
results of the pen and field trials suggests that pen trials can assist in the
development of more effective bait types. However, conclusions about the
relative efficacy of bait types drawn from the results of baiting programs
that measure only bait uptake are unlikely to be reliable.
Pythons in the pergola: the ecology of 'nuisance' carpet pythons (Morelia spilota) from suburban habitats in south-eastern Queensland
Authors: Fearn S. , Robinson B. , Sambono J. , Shine R.
Published: September 2002

Carpet pythons (Morelia spilota) are large (to >4 m,
11 kg) non-venomous snakes that are widely distributed across mainland
Australia. In many parts of their range, viable populations persist even in
highly disturbed urban and suburban habitats. Over a six-year period, we
collected 258 ‘nuisance’ pythons from two cities (Brisbane and
Ipswich) in south-eastern Queensland. Most of these snakes were reported by
members of the general public, often after the snakes had consumed domestic
pets or cage-birds. We provide data on seasonal activity patterns, body sizes,
sexual size dimorphism, reproduction and food habits of these snakes. Snakes
were active and fed year-round, primarily on domestic and commensal birds and
mammals. Dietary composition shifted with body size: one small snake consumed
a lizard, intermediate-sized snakes took mostly mice, rats and parrots, and
large snakes fed on larger items such as cats, brushtail possums and poultry.
Adult male pythons engaged in combat bouts during the breeding season, and
(perhaps as an adaptation to enhance success in such bouts) grew larger and
were more heavy-bodied than conspecific females.
Australian fur seals, Arctocephalus pusillus doriferus: pup numbers at Lady Julia Percy Island, Victoria, and a synthesis of the species' population status
Authors: Shaughnessy P. D. , Kirkwood R. J. , Warneke R. M.
Published: September 2002

The abundance of Australian fur seal pups was determined at Lady Julia Percy Island in early January 2000 when the average age of pups was 5 weeks. A mark-recapture procedure with repeated recapture sessions was used to estimate abundance of pups in six accessible breeding areas. Pups (n = 1836) were marked by clipping guard hair on the head. Recaptures were conducted visually on 2-4 occasions, when a mean of 41% of sighted pups had been marked. Pup numbers were calculated using a modified Petersen estimate and combined by taking their arithmetic mean. The combined estimate in the accessible breeding areas was 4487 380 pups were counted at two inaccessible sites and 347 dead pups were recorded. Overall, the estimate of abundance for Lady Julia Percy Island was 5214 pups. This exceeds three previous estimates of doubtful veracity for pupping seasons in 1935-36, 1975-76 and 1986-87, and is the greatest number of pups recorded at any Australian fur seal colony. Summation of the most recent estimates of abundance of Australian fur seal pups in all colonies indicates pup production of 16 900 per annum in the 1990s. New Zealand fur seals were also breeding on the island (a mating and four new-born pups were recorded) and two adult male Australian sea lions were observed.
Relative importance of plague rodents and dasyurids as prey of barn owls in central Australia
Authors: Heywood M. R. , Pavey C. R.
Published: September 2002

We examined the diet of the barn owl in three bioregions of arid Northern Territory; two in upland areas, the other on the Barkly Tableland. Owls from the MacDonnell and Petermann Ranges fed predominantly on rodents. At both sites, Mus musculus was the dominant prey both in terms of frequency and prey units, with Pseudomys hermannsburgensis an important secondary item. Notomys alexis was an important secondary item in the MacDonnell Ranges. These results support previous research in highlighting the importance of plague rodents in the diet of barn owls in arid Australia. In contrast to the samples from the upland sites, the Barkly Tableland sample was composed mostly of the dasyurid marsupial Sminthopsis macroura, with only one rodent captured. The absence of the long-haired rat, Rattus villosissimus, from the sample, despite the species being a favoured prey item of the barn owl that undergoes population irruptions at the collection site, suggests that the sample was collected during a non-plague period. Our study is the first to record a marsupial species as the major prey of the barn owl. This finding suggests that barn owls can switch to other prey when populations of rodents crash.
Foraging ecology of the black flying fox (Pteropus alecto) in the seasonal tropics of the Northern Territory, Australia
Authors: Palmer Carol , Price Owen , Bach Christine
Published: September 2002

Pteropus alecto uses landscape patchiness at
two scales: firstly, between broad vegetation types (i.e. eucalypt open
forest/savanna woodland versus rainforest vegetation); secondly, within
vegetation types. Radio-collared Pteropus alecto
selected foraging sites that were richer in flower or fruit resources than
floristically similar sites and moved through the landscape in response to the
flowering and fruiting of a number of plant species occurring in different
vegetation types. Abundance of P. alecto within four
monitored rainforest patches and the outside vegetation fluctuated
substantially during the study. Overall, P. alecto was
more abundant in the rainforests than in the surrounding vegetation.
P. alecto foraged on the flowers and fruit from 23
species in 11 families.