NASA/TMm2000-209891, Vol. 49

Technical Report Series on the

Boreal Ecosystem-Atmosphere Study (BOREAS)

Forrest G. Hall and Jaime Nickeson, Editors

Volume 49

BOREAS RSS-4 1994 Southern Study Area

Jack Pine LAI and FPAR Data

Stephen Plummer, Institute of Terrestrial Ecology, UK

National Aeronautics and

Space Administration

Goddard Space Flight Center

Greenbelt, Maryland 20771

July 2000

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NASA/TMm2000-209891, Vol. 49

Technical Report Series on the

Boreal Ecosystem-Atmosphere Study (BOREAS)

Forrest G. Hall and Jaime Nickeson, Editors

Volume 49

BOREAS RSS-4 1994 Southern Study Area

Jack Pine LAI and FPAR Data

Stephen Plummer, Institute of Terrestrial Ecology, UK

National Aeronautics and

Space Administration

Goddard Space Flight Center

Greenbelt, Maryland 20771

July 2000
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Hanover,MD21076-1320

PriceCode:A17

Availablefrom:

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PriceCode:A10
BOREAS RSS-4 1994 Southern Study Area Jack Pine LAI and FPAR

Data

Stephen Plummer

Summary

The RSS-4 team collected several data sets related to leaf, plant, and stand physical, optical, and

chemical properties. This data set contains leaf area indices and FPAR measurements that were taken at

the three conifer sites in the BOREAS SSA during August 1993 and at the jack pine tower flux and a

subset of auxiliary sites during July and August 1994. The measurements were made with LAI-2000

and Ceptometer instruments. The measurements were taken for the purpose of model parameterization

and to test empirical relationships that were hypothesized between biophysical parameters and remotely

sensed data. The data are stored in tabular ASCII files.

Table of Contents

1) Data Set Overview

2) Investigator(s)

3) Theory of Measurements

4) Equipment

5) Data Acquisition Methods

6) Observations

7) Data Description

8) Data Organization

9) Data Manipulations

10) Errors

11) Notes

12) Application of the Data Set

13) Future Modifications and Plans

14) Software

15) Data Access

16) Output Products and Availability

17) References

18) Glossary of Terms

19) List of Acronyms

20) Document Information

1. Data Set Overview

1.1 Data Set Identification

BOREAS RSS-04 1994 Southern Study Area Jack Pine LAI and FPAR Data

1.2 Data Set Introduction

Estimates of Leaf Area Index (LAI) and fraction of Photosynthetically Active Radiation (FPAR)

were made during the Focused Field Campaign in summer 1993 (FFC-93) and the second Intensive

Field Campaign (IFC-2) in 1994. In FFC-93, preliminary measurements were made using a LI-COR

LAI-2000 and a Decagon Devices Ceptometer at the three conifer tower flux sites Young Jack Pine

(YJP), Old Jack Pine (OJP), and Old Black Spruce (OBS) in the BOReal Ecosystem-Atmosphere

Study (BOREAS) Southern Study Area (SSA), while in 1994 attention was focused on jack pine

tower flux and auxiliary sites in the SSA. LAI was estimated using both instruments; FPAR was

obtained using the Ceptometer. Both the Ceptometer and the LAI-2000 rely on the relationships

Page 1
betweenradiationtransmission,canopygapfraction,andLAI. Theassumptionsof theseapproaches

aresummarizedbelow(seeSection9) andhavebeenassessedfor theBOREASsitesin Chenetal.

(1997).

1.3 Objective/Purpose

TheRemoteSensingScience(RSS)-04investigationsweredesignedto obtainLAI, FPAR,and

foliar chemistrydatafor acomplexspatiallyvariableforestcanopyin orderto:

• Parameterizeanecosystemsimulationmodel.

• Testempiricalrelationshipshypothesizedbetweenbiophysicalparametersandremotely

senseddata.

• Parameterizeaforestreflectancemodelandcompareit with AirborneVisibleandInfrared

ImagingSpectrometer(AVIRIS) datato deducewhetherobserved'relationships'between

canopychemistryandreflectanceareaproductof canopystructureratherthanfoliar chemical

variationsthemselves(seereferenceslist andbiochemistrydataset).

• Drive theecosystemsimulationmodelwithestimatesof LAI andchemistryderivedfrom

remotelysenseddata.

1.4 Summary of Parameters

LAI, FPAR.

1.5 Discussion

Themeasurementsthatcomprisethisdatasetwerecollectedasacontributiontothedetermination

of thebiophysicalcharacteristicsof theBOREASSSA.

1.6 Related Data Sets

BOREASRSS-01SSAPARABOLA SurfaceReflectanceandTransmittanceData

BOREASRSS-041994JackPineLeafBiochemistryandModeledSpectrain theSSA

BOREASRSS-07LAI, GapFraction,andFPARData

2. Investigator(s)

2.1 Investigator(s) Name and Title

Dr. Stephen Plummer

Professor Paul Curran

2.2 Title of Investigation

RSS-04: Coupling Remotely Sensed Data to Ecosystem Simulation Models

2.3 Contact Information

Contact 1:

Dr. Stephen Plummer

Role: Data collection, transport, and project supervision

Section for Earth Observation

Institute of Terrestrial Ecology

Monks Wood

Abbots Ripton

Cambs, PE17 2LS UK

+44 1487 773381 (tel)

+44 1487 773277/467 (fax)

S.Plummer@ite.ac.uk

*formerly Remote Sensing Applications Development Unit British National Space Centre

Page 2
Contact 2:

Jaime Nickeson

Raytheon ITSS

NASA GSFC

Code 923

Greenbelt, MD 20771

(301) 286-3373

(301) 286-0239 (fax)

Jaime.Nickeson@ gsfc.nasa.gov

3. Theory of Measurements

For a discussion of the theory behind measurements presented here, users are directed to the review by

Welles (1990), Welles and Norman (1991), and Chen et al. (1997).

4. Equipment

4.1 Sensor/Instrument Description

i) LAI

Two instruments were used to estimate LAI: a LI-COR LAI-2000 leaf area meter and a Decagon

Devices Ceptometer. The LAI-2000 uses either one or two sensors to make measurements of the

incoming diffuse incident flux above (A) and below (B) the canopy in blue wavelengths (<490 nm).

Each reading comprises measurements of the amount of radiation at five zenith angles simultaneously

over either the full azimuth or some portion of it, dictated by a viewing mask attached to the optical

head. One measurement comprise a minimum of 10 numbers corresponding to 5 values of A (above)

and 5 of B (below), at zenith angles of 0, 22.5, 37.5, 52.5, and 67.5 degrees. The Ceptometer is a

line quantum sensor consisting of 80 separate photodiodes spaced at 1-cm intervals that are sensitive to

radiation in the PAR region (400-700 nm). Measurements above and below the canopy are made to

determine canopy transmittance at a number of solar zenith angles.

ii) FPAR

The Ceptometer was also used to determine the fraction of PAR absorbed by the canopy at a

number of solar zenith angles.

4.1.1 Collection Environment

Measurements were collected during ambient surface atmospheric conditions at the SSA during

August 1993 (FFC-93) and July to August 1994 (IFC-2). The LAI-2000 measurements were made at

dusk and dawn, Ceptometer data were collected on sunny days.

4.1.2 Source/Platform

The instruments were held by the human investigators.

4.1.3 Source/Platform Mission Objectives

The objective was to collect LAI and FPAR measurements at various locations.

4.1.4 Key Variables

LAI, FPAR, Mean Tip Angle

Page 3
4.1.5 Principles of Operation

The LAI-2000 and Ceptometer are instruments that make measurements of the incoming radiation

below a plant canopy. In the case of the LAI-2000, measurements are made in the blue (<490 nm)

region, while the Ceptometer records incoming radiation in the PAR (400-700 nm) region. These data

can be used to estimate LAI indirectly by making assumptions about the canopy architecture (leaf

distribution). LAI is derived by inverting the radiation transmission (or gap fraction) information. The

gap fraction is the fraction of view in any direction from below a plant canopy that is not blocked (by

leaves). If it is assumed that leaves are the only elements that block radiation, that they are

nontransmitting, and that they are randomly distributed in space, then the transmission of a beam of

radiation can be related to the mean foliage density (see Section 9 for equations). If the canopy is

horizontally homogenous, then the mean foliage density can be related to LAI.

The LAI-2000 can be considered to be analogous to hemispherical photography in that it uses a

fish eye light sensor that measures diffuse radiation in five distinct angular bands about zenith. The

incoming radiation is projected onto photodiodes arranged as concentric rings. To derive gap fraction

information, light conditions are assumed diffuse and uniform (dusk, dawn, or overcast conditions),

and measurements are made of the sky above the canopy followed by readings below the canopy. The

ratio of above-to-below canopy readings is used to obtain gap fraction. Because foliage is not normally

randomly distributed and there is a proportion of nonfoliage matter that blocks radiation (dead leaves,

branches, stems, or trunks), the derived measurement is normally referred to as "effective" LAI.

Correction of these measurements can be made by derivation of factors that represent the

woody-to-total area ratio and the clumping factors (needle-to-shoot area ratio and foliage clumping at

greater than shoot level).

The Ceptometer measures PAR radiation using 80 photodiodes spaced at each centimeter along an

80-cm rod. These are used to provide an average value of PAR over the 80-cm length and for the

specific solar zenith angle and relative azimuth. To account for azimuthal variation in foliage

distribution, it is advisable to use the average over several azimuth directions (in this case, eight).

Because the instrument is primarily used to measure the fraction of absorbed PAR (FPAR),

measurements are taken in direct sun conditions, with the proviso that the solar illumination is

consistent over the period of measurement. In the same way as with the LAI-2000, measurements are

obtained first outside the canopy and subsequently below the canopy. In line with gap fraction

measurements, these can be converted into an estimate of LAI using the approach of Norman (1988)

(see Section 9). This also requires measurement of the ratio of diffuse-direct incident radiation. The

diffuse component can be obtained by shading the Ceptometer from direct sun using an appropriately

sized object such that the entire length of instrument is covered for the width of the solar disk (this is

an acquired skill). More recent instruments (Delta-T SunScan6) come with a separate quantum sensor

and shading ring for use with a line PAR sensor. Chen et al. (1997) indicate that the Ceptometer

provides a measurement of plant area index, although the finite averaging does account for error

caused by clumping at scales larger than the averaging length.

4.1.6 Instrument Measurement Geometry

LAI-2000

The LAI-2000 is simple to operate and acquires data relatively fast. Operation can be through

single-head, dual-head, or remote-head modes. In single-head mode, as used in this experiment, both

A (above) and B (below) measurements are made with the same optical head. Because the calculation

is made by comparison of A and B measurements, the instrument does not require either absolute or

relative calibration. However, there is a need for ready access to a clear sky view near to the

measurement site. In BOREAS operation, this caused difficulties, especially at mature pine sites with

tree heights of approximately 15 m. Measurements had to be tailored to site conditions, and given the

need to cover as many sites as possible, operation often occurred in nonoptimal conditions. Sites were

measured at dawn or dusk, although the distance between sites limited coverage on any given day. For

short tree sites, e.g., SSA-YJP, it was possible to get above the canopy (using the back of a standard

Jeep or by climbing the flux tower in periods of nonoperation (1993) to a height of approx. 3-4 m).

The LAI-2000 head requires leveling, but it contains a bubble level to make leveling easier. The best

Page 4
practiceis to maintaininstrumentorientationfor all measurements(A andB).Thisisparticularly

importantwheretheavailabilityof aclearareais restrictedto aloggingroad.In suchcases,theA

readingwasmadefrom thebackof aJeepwith theopticalheadmaskeddownwardsuchthatonly a

proportionof theview wasused(seeSection5). In all cases,theopticalheadwasmaskedfor the

observerusinga45-degreemaskunlessmorewasrequired.A measurementsweremadeasregularly

aspossible(beforeandaftersingleBruns)to minimizetheeffectof variationin skyconditionsand

linearinterpolationusedto provideA valuesfor eachBvalue.Repetitionsof eachmeasurementwere

madeto increasetherepresentativeness, andin caseswheretheBvalueexceededacorrespondingA

thedatapointwasignored.Thisusuallyappliedto measurementsfromthefifth ring.Removalof the

fifth ring measurementin softwaremeantthatthedatacouldbereintroduced.In all cases,the

measurementsweremadeatthesameheight,1m abovetheground,exceptforreference

measurements. Thelatterweremade1m abovethecanopy(F8L6T),from thetopof alargeflux tower

(G2L3T),or from aJeep+ 1m height.

Ceptometer

As with theLAI-2000,thereareanumberof issuesthataffecttherepresentativenessof

measurementsmadewith theCeptometer.In all cases,referencemeasurementsweremadeatthesame

locationsasfor theLAI-2000,andall measurementrunsstartedandfinishedwith areference

measurement.Sincethesamesetof measurementswasusedfor FPARandLAI, thesemeasurements

wereall madeunderdirect sunconditionsandincludeddiffuseincident,canopy,andunderstory

measurements. Eachmeasurementcomprisedeightazimuthdirectionswith theinstrumentlevelandout

of anyshadowcastby theoperator.Theeightmeasurementsweremadeatthecardinalandsubcardinal

directions.Measurementsweremadeatapproximately1m wheresignificantunderstoryexistedor 30

cm abovegroundwheretheunderstorywasmoss/lichen.Experiencedictatedwhetheraparticularset

of measurementswasacceptable,especiallyfor diffusemeasurements, whichrequiredshadingof the

80photodiodes.It shouldbenotedthatbecauseeachindividualmeasurement(1 through8)was

averaged"on thefly," oneunshadeddiffusemeasurementcouldbiasthedata.Whenthisoccurred,

measurementswererepeated.A measurementsequencetookconsiderablylongerthantheequivalent

LAI-2000, andtheprocessingwasmorelaboriousbecauseno softwarewaswrittenforthispurpose.

Thisisnow availablewiththeDelta-TSunscan6andmaybeavailablewiththeDecagonAccupar6.

4.1.7 Manufacturer of Instrument

LI-COR LAI-2000:

LI-COR, Inc.

4421 Superior Street

P.O. Box 4425

Lincoln, NE 68504

(402) 467-3576

http://env.licor.com/products/LAI2000/2000.htm

Ceptometer:

Decagon Devices, Inc.

950 NE Nelson Ct.

P.O. Box 835

Pullman, WA 99163

(509) 332-2756

http://www.decagon.com/

Page 5
4.2 Calibration

i) LAI-2000

Sensor calibration consists of five multipliers for the outputs of the five rings of the detector. These

values are supplied on a calibration sheet and relate one ring to another. The values do not convert

outputs to absolute values of energy. In one-sensor mode, this is unimportant because the same sensor

makes both A and B measurements. In two-sensor mode, the two sensors are compared under the

same diffuse light conditions to adjust the sensitivity of the two sensors. The instrument is calibrated

using an integrating sphere supplied by the UK representatives of LI-COR, Inc., Glen Spectra Ltd.

ii) Ceptometer

For LAI and FPAR determination, as long as the relative calibration of the 80 sensors is consistent,

the same method applies as above. However, for determination of PAR, absorbed PAR (APAR), or

incident PAR (PAR0), calibration must be applied to convert from output to SI units (pmol/mZ/s).

Calibration is checked regularly by the owners of the instrument, University of Wales, Swansea, by

comparison against an accurate PAR sensor under a standard daylight lamp. The accurate PAR

quantum sensor is traceable to UK national standards.

4.2.1 Specifications

Ceptometer - The ideal spectral response for a quantum sensor is a "top hat" function with 100%

dropoff at 400 nm and 700 nm. All quantum sensors approximate this; however, errors caused by

imperfect spectral response are small for daylight conditions. The system cosine response matches the

ideal accurately (>90% below 70 degrees). Individual Ceptometer measurement time is nominally 120

ms over a range of 2500 pmol/mZ/s with a resolution of 0.3 pmol/mZ/s. Accuracy of the instrument is

+ 10%. Maximum recorded values were approximately 1,500 pmol/mZ/s.

The LAI-2000 measurements were made in one-sensor mode because calculation is based on the

ratio of A to B measurements. Issues of calibration, resolution, and accuracy are not a problem

provided that the relative calibration between individual view tings is accurate and consistent.

4.2.1.1 Tolerance

Ceptometer - Accuracy of the instrument is _ 10%. Maximum recorded values were approximately

1,500 pmol/mZ/s, well within the stated instrument range. Comparison of Ceptometer measurements

against the Tracing Radiation and Architecture of Canopies (TRAC) instrument indicated a discrepancy

of approximately 200 counts, but this was consistent over a range of light conditions. Absolute values

of PAR were therefore not reported. Error analysis for the FPAR measurements could not be

conducted against those from other Principal Investigators (PIs) (Chen, RSS-07) because

measurements were not coincident. Within canopy variability (n=10) indicates that for FPAR values

greater than 0.7, an error of +10% should be expected, but because of clumping this can rise to

20-30% for FPAR values of 0.5.

The LAI estimates from the Ceptometer, LAI-2000, TRAC, and allometry were assessed by Chen

et al. (1997). All the methods have limitations, and an absolute accuracy could not be attributed to any

one method. The error range for LAI measurement method is on the order of 15-30%.

4.2.2 Frequency of Calibration

See Section 4 comments above - all measurements are ratio values, and the only issue is sensitivity

of the instrument across the measurement range. This has not been checked but is assumed to be

acceptable. Intercalibration between instruments was not performed for the LAI-2000 because it was

used in one-sensor mode. Comparison of Ceptometer measurements against the TRAC instrument

indicated a discrepancy of approximately 200 counts, but this was consistent over a range of light

conditions. Absolute values of PAR are not provided in this data set.

4.2.3 Other Calibration Information

None given.

Page 6
5. Data Acquisition Methods

1993 Procedure:

i) LAI using the LAI-2000

At each of the three conifer tower flux sites, 100-m transects were established with access to a

nonforest area for determination of radiation flux.

liii_iiiiiii_iiiiiiiii!i!!iiii

iiiiiiiiiiiiiiiiiiiiiiii!i!!

At the SSA-YJP site, four transects were laid out on the cardinal points centered on the road next to

the site hut (see accompanying .gif file). Data acquisition comprised an A measurement followed by 10

B measurements for each transect and finished with additional A measurement. A samples were taken

at the flux tower and B samples at 10-m intervals along each transect. Data were collected on

14-Aug-1993 at 08:00 local time (15:00 Greenwich Mean Time (GMT). All the A measurements were

acquired above the canopy at 3-4 m using the steps on the flux tower. In all cases, a 45-degree view

cap was used to eliminate the observer.

Page 7
At theSSA-OJPsite,suitableaccessto aclearareaattheflux towersiteto makeirradiance

measurementswasnot available.Therefore,asimilarstandadjacento thesiteaccessroadnearasmall

lake(seeaccompanying.gif file) wasselected.Irradiancemeasurementsweretakenat thelakeedge

usinga 180-degreeview cap.Fourtransectswereestablished;however,therestrictedsizeof thestand

requiredareorientationof thesetransectsatsomepoint alongthe100-mlength.Datawereacquiredon

16-Aug-1993at 05:20(12:20GMT) and06:30(13:30GMT).

Page8
Similarly,in theSSA-OBS,reasonableaccessto theflux towersitein 1993wasunavailableand

therewasnoaccessabovethecanopy.Transectswerethereforeestablishednearertheroad,andthe

roadservedastheirradiancesitewith a315-degreeview cap.A transectwasestablishedin eachof the

two mainstratatypes,tall, highLAI blackspruce,andshort,low LAI black spruce.Datawere

acquiredevery5metersto giveasamplesizeof 20for eachtransect.Datawererecordedon

25-Aug-1993at 13:30(20:30GMT).

LAI wascalculatedusingoptionsavailablein theLAI-2000processingsoftware.Fourdifferent

methodswereused:standard,slope/intercept(Lang,1987),ellipsoidalleafdistribution(Campbell,

1986),andconstrainedleastsquares(NormanandCampbell,1989).

ii) LAI using the Ceptometer

At thesamesitesasin i), measurementsweremadeseveraltimesperday.Eachmeasurementona

transectwastheaverageof eightazimuthalmeasurementsofPARflux. Totalanddiffuseincidentflux

weremeasuredbeforeandaftereachtransectusingashadeto block thesun.Similarly,atthefirst and

lasttransectpoint,diffusewithin-canopyflux andPARreflectedby theunderstoryweremeasured.

LAI wasdeterminedempiricallyusingthemethoddescribedby Norman(1988)withthebeamfraction

determinedby interpolationfor eachtransectpoint(seeSection9).

iii) FPAR

Themeasurementsdescribedabovefor theCeptometer were also used to calculate the variation in

FPAR for each transect using measurements of canopy transmission and interpolated values of incident

flux and soil reflected flux. The canopy reflected flux was calculated using an average of eight

measurements of a short roadside tree. FPAR was calculated for three solar zenith angles and for two

transects at each site.

Page 9
1994 Procedure:

i) LAI with the LAI-2000

The data acquisition in 1994 concentrated on the jack pine tower and auxiliary sites in the SSA and

covered the same transects/plots as those laid out by RSS-07 and Terrestrial Ecology (TE)-23 for

allometric measurements. For each auxiliary site, this comprised two perpendicular 50-m transects

oriented in due S-N and E-W directions. Deviation from such an arrangement is explained in Section

6.

A total of nine jack pine sites were sampled with the LAI-2000. In all cases, the data were acquired

either before sunrise or after sunset and with a large view cap (315 or 330 degrees) because the only

irradiance site in most cases was the access road. Tree edge effects were reduced by measuring

irradiance from the top of a Jeep.

ii) LAI with the Ceptometer

Ceptometer data were acquired at the same sites as the LAI-2000 using the method described above

for 1994 site locations. Ten sites were covered, with runs recorded at three solar zenith angles for

seven of the sites and two solar zenith angles for the other three sites. In addition, a series of

comparative analyses was conducted with Jing Chen (RSS-07) at the following sites: SSA-Young

Aspen (YA) (D6H4T), Black Spruce (DOH6S) and Mixed (D911M) and with Don Deering (RSS-01) at

the SSA-OJP.

iii) Fraction of Absorbed Photosynthetically Active Radiation (FPAR)

Measurements of FPAR for each of the sites above were also made using the method described in

1993. At sites with significant understory vegetation, additional measurements were made above and

below the understory (D6H4T, DOH6S).

iv) Canopy Chemistry

Samples for determination of nitrogen, chlorophyll, water, etc., were acquired for the nine sites

covered by the LAI-2000 using clippers for the short sites and with a shotgun for the sites with tall

canopies. Branchlets were subdivided into current year and 1 year or greater, and the needles were

then stripped off and frozen with CO2 (see related data sets Section 1.6).

6.1 Data Notes

None given.

Date

27- Jul- 1994

27-Jul- 1994

27-Jul- 1994

28-Jul- 1994

28-Jul- 1994

28-Jul- 1994

30-Jul- 1994

2-Aug- 1994

2-Aug- 1994

2-Aug- 1994

6. Observations

Notes

Site D911M Run 1: Transect of Pink Flags E/W from Tower - TE-06?

Run 2: Transect of Red Stakes N/S from Tower - RSS-07.

Site D4H6T Aspen: Understory data acquired with Ceptometer.

Site DOH6S Black Spruce: Cirrus Cloud. Problem finding site. Used RSS-07

Transect.

Site G9LOP: Cirrus Cloud.

Site F7J1P: Cumulus Cloud.

Comparison of Ceptometer with TRAC.

Site GSL6P: No Markers present - Markers inserted N/E/S/W.

Site F516P: Site not found so established at 150 m in from Route 913 on a bearing

of 59 degrees.

Site F7J1P: 60% Jack Pine, 20% Spruce, 20% Aspen.

Site F7JOP: 34% Jack Pine, 33% Spruce, 33% Aspen.

Page 10
7. Data Description

7.1 Spatial Characteristics

7.1.1 Spatial Coverage

Data were collected at treed SSA tower sites and SSA jack pine auxiliary sites. The following table

lists the North American Datum of 1983 (NAD83) coordinates of the site locations that were sampled"

Name Notes

West North UTM UTM UTM

Longitude Latitude Easting Northing Zone

F8L6T SSA YJP 104

G2L3T SSA OJP 104

G814T SSA OBS 105

F516P JIH-4 Pine 105

F7JOP JMH-5 Pine 105

F7JIP JMH-A2 Pine 105

GIK9P JMM-6 Pine 104

G4K8P JMM-5 Pine 104

G7K8P JMM-8A Pine 104

G8L6P JDM-8 Pine 104

G9LOP JMH-10 Pine 104

DOH6S BMM-I Spruce 105

DOH4T SSA YA 105

D9IIM AIH-3 Mixed 105

64527 53

69203 53

11779 53

11174 53

05116 53

03226 53

74810 53

76399 53

77147 53

63755 53

73778 53

29534 53

32313 53

20643 53

87581 523350

91634 520257

98718 492306

86608 492681

88334 496666

88211 497909

90881 516576

91884 515529

95882 515023

96558 523807

97576 517227

64878 480506

65602 478675

72540 486410

7 5969540

0 5974035

1 5981879

9 5968405

7 5970320

2 5970183

8 5973183

6 5974295

9 5978742

6 5979530

6 5980634

0 5944267

2 5945077

2 5952768

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

0 13

7.1.2 Spatial Coverage Map

Not available.

7.1.3 Spatial Resolution

The measurements provided by the LAI-2000 should be regarded as representative of the sample

site, while those by the Ceptometer (LAI and FPAR) are provided as individual samples for each

sample point. It is recommended that these also be used at the sample site level rather than individually

since the variation from point to point can be large because of clumping; this is particularly important in

the case of FPAR. Where there was significant understory, the Ceptometer data are provided at two

levels, above and below the understory layer.

7.1.4 Projection

Not applicable.

7.1.5 Grid Description

Not applicable.

7.2 Temporal Characteristics

7.2.1 Temporal Coverage

FFC-93: 07-Aug to 30-Aug-1993

IFC-94: 25-Jul to 05-Aug-1994

7.2.2 Temporal Coverage Map

1993 LAI using the LAI-2000

SSA-YJP - Data were collected on 14-Aug

SSA-OJP - Data were acquired on 16-Aug

(13:30 GMT)

SSA-OBS - Data were recorded on 25-Aug

at 08:00

at 05:20

at 13:30

local time

(12:20 GMT)

(20:30 GMT) .

(15:00 GMT) .

and 06:30

Page 11
1993 LAI using the

SSA-YJP - Data were

SSA-OJP - Data were

SSA-OBS - Data were

Ceptometer

collected several times a day on 14-Aug.

acquired several times a day on 16-Aug.

recorded several times a day on 25-Aug.

1994 LAI using the LAI-2000

F516P - 04-Aug-1994

F7JOP - 03-Aug-1994

F7JOP - 31-Jui-1994

F7JIP - 03-Aug-1994

F7JIP - 31-Jui-1994

GIK9P - 31-Jui-1994

G2L3T - 05-Aug-1994

G4K8P - 31-Jui-1994

G7K8P - 31-Jui-1994

G8L6P - 05-Aug-1994

G9LOP - 03-Aug-1994

G9LOP - 31-Jui-1994

1994 LAI using the Ceptometer

DOH6S - 28-Ju1-1994

D6H4A - 27-Jui-1994

D9IIM - 27-Jui-1994

F516P - 03-Aug-1994

F516P - 04-Aug-1994

F7JOP - 04-Aug-1994

F7JOP - 28-Jui-1994

F7JIP - 03-Aug-1994

F7JIP - 28-Jui-1994

F8L6T - 02-Aug-1994

F8L6T - 30-Jui-1994

GIK9P - 26-Jui-1994

G2L3T - 30-Jui-1994

G4K8P - 26-Jui-1994

G4K8P - 27-Jui-1994

G7K8P - 03-Aug-1994

G7K8P - 28-Jui-1994

G8L6P - 30-Jui-1994

G9LOP - 26-Jui-1994

G9LOP - 27-Jui-1994

G9LOP - 28-Jui-1994

7.2.3 Temporal Resolution

Measurements were made during FFC-93 and IFC-2 in 1994. LAI changes relatively slowly for

conifer species; hence, the values can be considered to be representative of the field campaign

specified. FPAR varies continuously, for a given location, as a function of solar geometry because

penetration is dependent on the interception of incident PAR by individual crowns clumped in a

nonrandom fashion. Three sets of measurements for each sample site are given along with time and

date to provide an indication of FPAR variability. Individual runs of measurements took approximately

10 minutes from first point to last plus the time taken to gain access to the site from the nearest clear

sky location (varied from 1-10 minutes with most sites less than 5 minutes).

Page 12
7.3 Data Characteristics

7.3.1 Parameter/Variable

The parameters contained in the data files on the CD-ROM are:

LAI from LAI-2000 :

Column Name

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

MASK

NUM OBS

LAI STD METHOD

MTA STD METHOD

LAI LANG METHOD

MTA LANG METHOD

LAI ELLIP METHOD

MTA ELLIP METHOD

LAI CLS METHOD

MTA CLS METHOD

GROUP PLOT

COMMENTS

CRTFCN CODE

REVISION DATE

LAI from Ceptometer:

Column Name

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

LOCATION

LAI

FPAR

GROUP PLOT

COMMENTS

CRTFCN CODE

REVISION DATE

Page 13
7.3.2 Variable Description/Definition

The descriptions of the parameters contained in the data files on the CD-ROM are:

LAI from LAI-2000 :

Column Name Description

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

MASK

NUM OBS

LAI STD METHOD

MTA STD METHOD

LAI LANG METHOD

MTA LANG METHOD

LAI ELLIP METHOD

MTA ELLIP METHOD

LAI CLS METHOD

MTA CLS METHOD

GROUP PLOT

COMMENTS

The identifier assigned to the site by BOREAS,

in the format SSS-TTT-CCCCC, where SSS identifies

the portion of the study area: NSA, SSA, PEG,

TRN, and TTT identifies the cover type for the

site, 999 if unknown, and CCCCC is the identifier

for site, exactly what it means will vary with

site type.

The identifier assigned to the sub-site by

BOREAS, in the format GGGGG-IIIII, where GGGGG is

the group associated with the sub-site

instrument e.g. HYD06 or STAFF, and IIIII is the

identifier for sub-site, often this will refer to

an instrument.

The date on which the data were collected.

The Greenwich Mean Time (GMT) when the data were

collected.

The identifier given to the BOREAS auxiliary and

tower sites during the execution of field

operations. An example of this is B9B7A.

A number representing the presence or absence of

five azimuthal viewing mask rings for each

measurement.

Number of observations of the given sample used

to calculate given values.

Leaf angle index calculated by the standard

method with the LICOR LAI-2000.

Mean tip angle calculated by the standard method

with the LICOR LAI-2000.

Leaf angle index calculated by the slope/

intercept method of Lang (1987) with the LICOR

LAI-2000.

Mean tip angle calculated by the slope/intercept

method of Lang (1987) with the LICOR LAI-2000.

Leaf angle index calculated by the elliptical

distribution method of Norman and Campbell (1989)

with the LICOR LAI-2000.

Elliptical distribution method of Norman and

Campbell (1989) for determining the mean tip

angle with the LICOR LAI-2000.

Leaf angle index calculated by the constrained

least squares method of Norman and Campbell

(1989) with the LICOR LAI-2000.

Mean tip angle calculated by the constrained

least squares method of Norman and Campbell

(1989)with the LICOR LAI-2000.

Group associated with or who has defined location

information.

Descriptive information to clarify or enhance the

Page 14
CRTFCN CODE

REVISION DATE

LAI from Ceptometer:

Column Name

understanding of the other entered data.

The BOREAS certification level of the data.

Examples are CPI (Checked by PI), CGR (Certified

by Group), PRE (Preliminary), and CPI-??? (CPI

but questionable).

The most recent date when the information in the

referenced data base table record was revised.

Description

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

LOCATION

LAI

FPAR

GROUP PLOT

COMMENTS

CRTFCN CODE

REVISION DATE

The identifier assigned to the site by BOREAS,

in the format SSS-TTT-CCCCC, where SSS identifies

the portion of the study area: NSA, SSA, PEG,

TRN, and TTT identifies the cover type for the

site, 999 if unknown, and CCCCC is the identifier

for site, exactly what it means will vary with

site type.

The identifier assigned to the sub-site by

BOREAS, in the format GGGGG-IIIII, where GGGGG is

the group associated with the sub-site

instrument e.g. HYD06 or STAFF, and IIIII is the

identifier for sub-site, often this will refer to

an instrument.

The date on which the data were collected.

The Greenwich Mean Time (GMT) when the data were

collected.

The identifier given to the BOREAS auxiliary and

tower sites during the execution of field

operations. An example of this is B9B7A.

Specific position within the site, relative to

the tower.

Leaf area index calculated from Ceptometer

measurements.

Fraction of photosynthetically active radiation

measured from Ceptometer instrument.

Group associated with or who has defined location

information.

Descriptive information to clarify or enhance

the understanding of the other entered data.

The BOREAS certification level of the data.

Examples are CPI (Checked by PI), CGR (Certified

by Group), PRE (Preliminary), and CPI-??? (CPI

but questionable).

The most recent date when the information in the

referenced data base table record was revised.

Page 15
7.3.3 Unit of Measurement

The measurement units for the parameters contained in the data files on the CD-ROM are:

LAI from LAI-2000 :

Column Name Units

SITE NAME [none]

SUB SITE [none]

DATE OBS [DD-MON-YY]

TIME OBS [HHMM GMT]

OP GRID ID [none]

MASK [unitless]

NUM OBS [counts]

LAI STD METHOD [unitless]

MTA STD METHOD [degrees]

LAI LANG METHOD [unitless]

MTA LANG METHOD [degrees]

LAI ELLIP METHOD [unitless]

MTA ELLIP METHOD [degrees]

LAI CLS METHOD [unitless]

MTA CLS METHOD [degrees]

GROUP PLOT [none]

COMMENTS [none]

CRTFCN CODE [none]

REVISION DATE [DD-MON-YY]

LAI from Ceptometer:

Column Name Units

SITE NAME [none]

SUB SITE [none]

DATE OBS [DD-MON-YY]

TIME OBS [HHMM GMT]

OP GRID ID [none]

LOCATION [none]

LAI [unitless]

FPAR [unitless]

GROUP PLOT [none]

COMMENTS [none]

CRTFCN CODE [none]

REVISION DATE [DD-MON-YY]

7.3.4 Data Source

The sources of the parameter values contained in the data files on the CD-ROM are:

LAI from LAI-2000 :

Column Name Data Source

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

MASK

[Assigned by BORIS Staff]

[Assigned by BORIS Staff]

[Observer]

[Observer]

[BOREAS Experiment Plan]

[LAI-2000]

Page 16
NUM OBS

LAI STD METHOD

MTA STD METHOD

LAI LANG METHOD

MTA LANG METHOD

LAI ELLIP METHOD

MTA ELLIP METHOD

LAI CLS METHOD

MTA CLS METHOD

GROUP PLOT

COMMENTS

CRTFCN CODE

REVISION DATE

LAI from Ceptometer:

Column Name

[LAI-2000]

[LAI-2000, calculated]

[LAI-2000, calculated]

[LAI-2000, calculated]

[LAI-2000, calculated]

[LAI-2000, calculated]

[LAI-2000, calculated]

[LAI-2000, calculated]

[LAI-2000, calculated]

[RSS04 team]

[RSS04 team]

[Assigned by BORIS Staff]

[Assigned by BORIS Staff]

Data Source

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

LOCATION

LAI

FPAR

GROUP PLOT

COMMENTS

CRTFCN CODE

REVISION DATE

[Assigned by BORIS Staff]

[Assigned by BORIS Staff]

[Observer]

[Observer]

[BOREAS Experiment Plan]

[RSS04 team]

[Ceptometer]

[Ceptometer]

[RSS04 team]

[RSS04 team]

[Assigned by BORIS Staff]

[Assigned by BORIS Staff]

7.3.5 Data Range

The following table gives information about the parameter values found in the data files on the

CD-ROM.

LAI from LAI-2000 :

Column Name

Minimum Maximum Missng Unrel Below

Data Data Data Data Detect

Value Value Value Value Limit

Data

Not

Cllctd

SITE NAME

SUB SITE

DATE OBS

TIME OBS

OP GRID ID

MASK

NUM OBS

LAI STD METHOD

MTA STD METHOD

LAI LANG METHOD

MTA LANG METHOD

LAI ELLIP METHOD

MTA ELLIP METHOD

LAI CLS METHOD

MTA CLS METHOD

SSA-9JP-AUX02 SSA-YJP-FLXTR None None None

RSS04-LAI01 RSS04-LAI01 None None None

14-AUG-93 05-AUG-94 None None None

122 2030 None None None

F516P G9LOP None None None

iiii iiiii None None None

i0 40 None None None

1.09 3.54 None None None

43 73 None None None

1.03 3.82 None None None

-999 None None

.92 3.69 None None None

31 75 None None None

.92 3.53 None None None

31 69 None None None

None

None

None

None

None

None

None

None

None

None

None

None

None

None

None

Page 17
GROUP PLOT None

COMMENTS N/A

CRTFCN CODE CPI

REVISION DATE 03-AUG-95

LAI from Ceptometer:

Minimum

Data

Column Name Value

TE-13 None None None None

N/A None None None Blank

CPI None None None None

25-OCT-96 None None None None

Maximum Missng Unrel Below Data

Data Data Data Detect Not

Value Value Value Limit Cllctd

SITE NAME SSA-9BS-AUX01 SSA-YJP-FLXTR None None None None

SUB SITE RSS04-LAI01 RSS04-LAI01 None None None None

DATE OBS 19-AUG-93 04-AUG-94 None None None None

TIME OBS 0 2357 None None None None

OP GRID ID DOH6S G9LOP None None None None

LOCATION 0 90 m None None None None

LAI .ii 7.81 None None None None

FPAR .04 .96 None None None None

GROUP PLOT RSS-I TE-6 None None None None

COMMENTS N/A N/A None None None Blank

CRTFCN CODE CPI CPI None None None None

REVISION DATE 07-AUG-95 25-OCT-96 None None None None

Minimum Data Value -- The minimum value found in the column.

Maximum Data Value -- The maximum value found in the column.

Missng Data Value -- The value that indicates missing data. This is used to

indicate that an attempt was made to determine the

parameter value, but the attempt was unsuccessful.

Unrel Data Value -- The value that indicates unreliable data. This is used

to indicate an attempt was made to determine the

parameter value, but the value was deemed to be

unreliable by the analysis personnel.

Below Detect Limit -- The value that indicates parameter values below the

instruments detection limits. This is used to

indicate that an attempt was made to determine the

parameter value, but the analysis personnel determined

that the parameter value was below the detection

limit of the instrumentation.

Data Not Cllctd -- This value indicates that no attempt was made to

determine the parameter value. This usually

indicates that BORIS combined several similar but

not identical data sets into the same data base table

but this particular science team did not

measure that parameter.

Blank -- Indicates that blank spaces are used to denote that type of value.

N/A -- Indicates that the value is not applicable to the respective column.

None -- Indicates that no values of that sort were found in the column.

Page 18
7.4 Sample Data Record

The following is a sample of the first few records from the data file on the CD-ROM

LAI from LAI-2000:

SITE NAME,SUB SITE,DATE OBS,TIME OBS,OP GRID ID,MASK,NUM OBS,LAI STD METHOD,

MTA STD METHOD,LAI LANG METHOD,MTA LANG METHOD,LAI ELLIP METHOD,MTA ELLIP METHOD,

LAI CLS METHOD,MTA CLS METHOD,GROUP PLOT,COMMENTS,CRTFCN CODE REVISION DATE

'SSA-YJP-FLXTR', 'RSS04-LAI01',I4-AUG-93,1500, 'F8L6T',IIIII,37 1.09,63,1.15,-999,

1.08,65,1.07,62, 'RSS-4', '', 'CPI',03-AUG-95

'SSA-YJP-FLXTR', 'RSS04-LAI01',I4-AUG-93,1500, 'F8L6T',IIIII,22 1.23,61,1.2,-999,

1.22,62,1.21,59, 'RSS-4', '', 'CPI',03-AUG-95

LAI from Ceptometer:

SITE NAME, SUB SITE, DATE OBS,TIME OBS,OP GRID ID,LOCATION, LAI,FPAR, GROUP PLOT,

COMMENTS,CRTFCN CODE,REVISION DATE

'SSA-9JP-AUX08', 'RSS04-LAI01',30-JUL-94, 1502, 'G8L6P', '3N',2.23, .71, 'RSS-4', ' ',

'CPI',25-OCT-96

'SSA-9JP-AUX08', 'RSS04-LAI01',30-JUL-94, 1507, 'G8L6P', '3W',2.12, .69, 'RSS-4', ' ',

'CPI',25-OCT-96

8. Data Organization

8.1 Data Granularity

The smallest unit of data tracked by the BOREAS Information System (BORIS) is all the data

collected at a site on a given day or for a given time period.

8.2 Data Format(s)

The Compact Disk-Read-Only Memory (CD-ROM) files contain American Standard Code for

Information Interchange (ASCII) numerical and character fields of varying length separated by

commas. The character fields are enclosed with single apostrophe marks. There are no spaces between

the fields.

Each data file on the CD-ROM has four header lines of Hyper-Text Markup Language (HTML)

code at the top. When viewed with a Web browser, this code displays header information (data set

title, location, date, acknowledgments, etc.) and a series of HTML links to associated data files and

related data sets. Line 5 of each data file is a list of the column names, and line 6 and following lines

contain the actual data.

9. Data Manipulations

9.1 Formulae

LAI-2000 method:

In calculation of LAI with the LAI-2000, the foliage density is derived by measurement of the

contact frequency over the azimuthal averaged zenith bin represented by each viewing ring. Foliage

density is calculated as:

p = (2 x pi)- ln(T(0))sin0/S(0) dO

where T(0) is the probability of noninterception, 0 is zenith angle, and S(0) is the path length. If

Page 19
thereis ahomogeneouscover,foliagedensityp is relatedto LAI by canopyheightandpathlengthSis

dependentoncanopyheightandzenithangle:

LAI = pz andS(0) = z/cos(0)

Thus,LAI canbecalculatedby summationof theazimuthalaveragedtransmissionoverthefive zenith

bins:

LAI = (2x pi) - ln(T(0))sin0cos0

Forborealforestcanopieswherethecoveris nothomogeneous(i.e.,thefoliagedistributionis not

random,andaproportionof theinterceptingelementsarenotfoliage),themeasurementis of effective

LAI (seeChenetal., 1997).To deriveLAI, it is necessaryto adjusttheeffectiveLAI for the

woody-to-totalarearatioandthefoliageclumpingbothwithinconifershootsandat largescales.A

discussionof thederivationof suchcorrectionfactorsis givenin Chenetal. (1997),with values

providedforthetowerflux sites.

Ceptometer Method:

Thederivationof LAI from Ceptometermeasurementsusestheformuladerivedby Norman(1988)

to convertfrom PARtransmissionto LAI. Thisapproachwasderivedfrom simulationresultsfrom a

radiativetransfermodelunderassumptionsof a sphericalleafangledistributionandrandomleaf

positioning.It doesnotinvolvegapfractionanalysisandcanbeusedwith anybeamfractionfrom

clearskyto overcast.Althoughit doesnotrequireaseriesof solarangles,averagingacrossarangeof

solarzenithanglesis recommended.Theempiricalfit of LAI toPARtransmissionis:

LAI = [{fb(1-cos0<s)-i } ln(Ei</Ea)]/(0.72-0.337fb)

fb = (Ea-gad)/ga

wherefbisthebeamfraction,Ei isincidentPARunderthecanopy,Ea is incident PAR above the

canopy, Ead is the diffuse incident PAR, and 0s is solar zenith angle.

Descriptions of these and other methods of LAI estimation can be found in the cited literature

(Section 17.2) and a review by Welles (1990).

FPAR is calculated using the following formula:

FPAR =(PARo - PARr- (PARt- PARs ))/PARo

The subscripts 0, r, t, and s refer to the incoming PAR, PAR reflected by the canopy, PAR transmitted

through the canopy, and PAR reflected by the substrate, respectively. The measurements in all cases

are the average of eight azimuthal measurements to eliminate azimuthal bias.

9.1.1 Derivation Techniques and Algorithms

None given.

9.2 Data Processing Sequence

9.2.1 Processing Steps

See Section 9.1.

9.2.2 Processing Changes

None.

Page 20
9.3 Calculations

i) LAI from LAI-2000

LAI was calculated using the LAI-2000 operating in one-sensor mode with one run constituting 10

B measurements separated by A measurements at the start and end of each run. Linear interpolation

between the A values was used to calculate A values for each B measurement. B values were rejected if

the B:A ratio was greater than 1 in any of the five rings.

ii) LAI from Ceptometer

Determined using the method of Norman (1988), a typical Ceptometer run comprised:

• Total incoming

• Diffuse incoming

• Canopy

• Measurement 1

• Substrate at Measurement 1

• Diffuse at Measurement 1

• Measurement 2

• Measurement 3 ....

• Measurement 10

• Total incoming

• Diffuse incoming

Linear interpolation based on time (decimal) for Total and Diffuse incoming was used to calculate

incoming for each measurement. Solar zenith angle was calculated based on the time and site

latitude/longitude obtained from the BOREAS Auxiliary Site Guide.

iii) FPAR from Ceptometer

FPAR calculations used the same data set and methods as ii) to determine the incoming. The

canopy and substrate components were as a percentage of incoming at each sample point.

9.3.1 Special Corrections/Adjustments

None given.

9.3.2 Calculated Variables

LAI, FPAR.

9.4 Graphs and Plots

None.

10. Errors

10.1 Sources of Error

None given.

10.2 Quality Assessment

10.2.1 Data Validation by Source

Checks were made prior to storage to make sure anomalous values were not stored. In the case of

LAI-2000, measurements were acquired only before sunrise and after sunset and in the absence of

significant amounts of cloud, or where the cloud was fast moving. Measurements were redone if the

number of invalid data points (indicated by an instrument beep) was higher than 2 on a standard run.

These data sets were discarded.

Similarly, where a single Ceptometer measurement contributing to the average was unexpectedly

Page 21
highor low, for examplein thecaseof diffusemeasurements, wheretheshadowingdevicewasnot

completelyovertheinstrument,theaveragewasrecalculatedusinganadditionaleightsamples.

10.2.2 Confidence Level/Accuracy Judgment

It is difficult to draw conclusions on the subjective quality of the data; however, it is clear that such

estimates are only as good as the assumptions made in derivation. The Chen et al. (1997) paper

discusses these assumptions for LAI and compares a range of instrument measurements. The cause

and effects of error on the representativeness of measurements varies with instrument and tree species,

and particularly with clumping at a range of scales. Nevertheless, the estimates are consistent with

alternative approaches.

10.2.3 Measurement Error for Parameters

Error in LAI from LAI-2000 and Ceptometer from Chen et al. (1997) varies with tree species, but

is in the range of 15-30%. This error is comparable but not necessarily the same as for allometry.

Error (n=10) in FPAR varies with the degree of clumping in a canopy but is typically less than

10% for FPAR of greater than 0.7. The error increases and may reach 30% where the canopy is highly

variable. There is no consistent pattern in error variation with solar geometry.

10.2.4 Additional Quality Assessments

None given.

10.2.5 Data Verification by Data Center

BORIS staff reviewed the data during the data base loading process for clarity and consistency.

11. Notes

11.1 Limitations of the Data

None given.

11.2 Known Problems with the Data

i) LAI from LAI-2000

The data set is exclusively of an incomplete conifer canopy. The assumptions in translating from

transmission to LAI may not strictly apply. In particular, the assumption of random arrangement of

needles in space is not true, which leads to underestimation of LAI. An empirical correction to convert

from shoot projected area to needle projected area has been suggested to adjust for this effect (Gower

and Norman, 1990). These empirical corrections, however, have not been applied to the data.

Representative correction values can be found in Chen et al. (1997), along with a discussion of their

use.

The irradiance measurement was constrained by access to an open area. In most cases, this was the

road. Edge effects were reduced by limiting the view azimuth and standing on a raised platform;

however, it is anticipated that there may still be some influence caused by the reduction in

representativeness of the azimuth average.

ii) LAI from Ceptometer

The azimuth averages of incoming PAR could potentially be biased by the presence of tree trunks

or gaps near the sample point. Variations in averages were noted by repeated sampling near the central

grid point. Absolute values of PAR are not given because cross comparison with the TRAC instrument

(Chen et al. 1997)(RSS-7) revealed a consistent discrepancy of approximately 230 counts.

iii) FPAR from Ceptometer

All values were calculated as an average of eight azimuth measurements. In the case of canopy and

substrate measurements, low incoming values resulted in null returns as an average. In these cases, the

percentage reflectance was derived from repeat measurements of the site.

Page 22
Thecanopymeasurementwasnotderivedunderidealconditionsbecauseit wasnotpossibleto

obtainPARreflectancefromtherealcanopy.Measurementsof shorttreesattheroadsidewere

substituted.Theaveragevalueswerenot azimuthindependentbecauseof problemswith thebias

introducedfrom directirradianceincidentontheCeptometerin theantisolardirection;therefore,

canopyvaluesmaynotbetrulyrepresentative.

Theaveragevalueswerecomputedandstoredby theinstrument,sonorecordof theeightvalues

thatgeneratedtheaverageis available.

11.3 Usage Guidance

Nonegiven.

11.4 Other Relevant Information

None.

12. Application of the Data Set

This data set can be used for model parameterization and to test empirical relationships hypothesized

between biophysical parameters and remotely sensed data.

None.

13. Future Modifications and Plans

14.1 Software Description

None given.

14.2 Software Access

None given.

14. Software

15. Data Access

The SSA jack pine LAI and FPAR data are available from the Earth Observing System Data and

Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive

Center (DAAC).

15.1 Contact Information

For BOREAS data and documentation please contact:

ORNL DAAC User Services

Oak Ridge National Laboratory

P.O. Box 2008 MS-6407

Oak Ridge, TN 37831-6407

Phone: (423) 241-3952

Fax: (423) 574-4665

E-mail: ornldaac@ornl.gov or ornl@eos.nasa.gov

Page 23
15.2 Data Center Identification

Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory

(ORNL) Distributed Active Archive Center (DAAC) for Biogeochemical Dynamics

http://www-eosdis.ornl.gov/.

15.3 Procedures for Obtaining Data

Users may obtain data directly through the ORNL DAAC online search and order system

[http://www-eosdis.ornl.gov/] and the anonymous FTP site [ftp://www-eosdis.ornl.gov/data/] or by

contacting User Services by electronic mail, telephone, fax, letter, or personal visit using the contact

information in Section 15.1.

15.4 Data Center Status/Plans

The ORNL DAAC is the primary source for BOREAS field measurement, image, GIS, and

hardcopy data products. The BOREAS CD-ROM and data referenced or listed in inventories on the

CD-ROM are available from the ORNL DAAC.

16. Output Products and Availability

16.1 Tape Products

None.

16.2 Film Products

None.

16.3 Other Products

These data are available on the BOREAS CD-ROM series.

17. References

17.1 Platform/Sensor/Instrument/Data Processing Documentation

None.

17.2 Journal Articles and Study Reports

Campbell, G.S. 1986. Extinction coefficients for radiation in plant canopies calculated using an

ellipsoidal inclination angle distribution. Agric. For. Meteorol. 36, 317-321.

Chen, J.M., P.M. Rich, S.T. Gower, J.M. Norman, and S.E. Plummer. 1997. Leaf area index of

boreal forests: Theory, techniques, and measurements. Journal of Geophysical Research 102(D24):

29,429-29,443.

Gower, S.T. and J.M. Norman. 1990. Rapid estimation of leaf area index in conifer and broad-leaf

plantations. Ecology, 72, 1896-1900

Lang, A.R.G. 1987. Simplified estimate of leaf area index from transmittance of the sun's beam.

Agric. For. Meteorology, 41,179-186.

Newcomer, J., D. Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J. Nickeson,

A. Papagno, D. Rinker, R. Strub, T. Twine, F. Hall, and P. Sellers, eds. 2000. Collected Data of The

Boreal Ecosystem-Atmosphere Study. NASA. CD-ROM.

Page 24
Norman,J.M. 1988.Cropcanopyphotosynthesisandconductancefrom leafmeasurements.

Workshoppreparedfor LI-COR, Inc.,Lincoln, NE.

Norman,J.M.andG.S.Campbell.1989.Canopystructure.In: PlantPhysiologicalEcology:Field

methodsandinstrumentation.(eds.R.W.Pearcy,J.Ehleringer,H.A. Mooney,andP.W.Rundel).

ChapmanandHall, LondonandNew York. 301-325.

North,P.R.1995.A three-dimensionalforestlight interactionmodelusinga Monte-Carlomethod.

IEEE Trans.Geosci.andRem.Sens.,34, 946-956.

North,P.R.andS.E.Plummer.1994.Estimationof coniferbi-directionalreflectanceusingaMonte

Carlomethod.IGARSS'94,IEEE, Piscataway,NJ,Vol. I, 114-116.

Plummer,S.E.andN. Lucas.1993.Reportof theBOREASIntensiveFieldCampaign1993.Remote

SensingApplicationsDevelopmentUnit,ReportNo.93/5.

Sellers,P.andF.Hall. 1994.BorealEcosystem-AtmosphereStudy:ExperimentPlan.Version

1994-3.0,NASA BOREASReport(EXPLAN 94).

Sellers,P.andF.Hall. 1996.BorealEcosystem-AtmosphereStudy:ExperimentPlan.Version

1996-2.0,NASA BOREASReport(EXPLAN 96).

Sellers,P.,F. Hall, andK.F. Huemmrich.1996.BorealEcosystem-AtmosphereStudy:1994

Operations.NASA BOREASReport(OPSDOC94).

Sellers,P.,F. Hall, andK.F. Huemmrich.1997.BorealEcosystem-AtmosphereStudy:1996

Operations.NASA BOREASReport(OPSDOC96).

Sellers,P.,F. Hall, H. Margolis,B. Kelly, D. Baldocchi,G. denHartog,J.Cihlar, M.G. Ryan,B.

Goodison,P.Crill, K.J.Ranson,D. Lettenmaier,andD.E. Wickland. 1995.Theboreal

ecosystem-atmospherestudy(BOREAS):anoverviewandearlyresultsfrom the1994field year.

Bulletinof theAmericanMeteorologicalSociety.76(9):1549-1577.

Sellers,P.J.,F.G.Hall, R.D.Kelly, A. Black, D. Baldocchi,J. Berry, M. Ryan,K.J. Ranson,P.M.

Crill, D.P.Lettenmaier,H. Margolis,J.Cihlar, J.Newcomer,D. Fitzjarrald,P.G.Jarvis,S.T.

Gower,D. Halliwell, D. Williams, B. Goodison,D.E.Wickland, andF.E.Guertin.1997.BOREAS

in 1997:ExperimentOverview,ScientificResultsandFutureDirections.Journalof Geophysical

Research102(D24):28,731-28,770.

Walker,G.K.,R.E.Blackshaw,andJ.Dekker.1988.Leaf areaandcompetitionfor light between

plant speciesusingdirecttransmission.WeedTechnology,2, 159-165.

Welles,J.M. 1990.Someindirectmethodsof estimatingcanopystructure.In: Instrumentationfor

StudyingVegetationCanopiesfor RemoteSensingin OpticalandThermalInfraredRegions.Remote

SensingReviews5(1) (eds.N.S.GoelandJ.M. Norman).HarwoodAcademicPublishers,London

andNewYork.

Welles,J.M. andJ.M.Norman.1991.Instrumentforindirectmeasurementof canopyarchitecture.

AgronomyJournal,83:818-825.

17.3 Arehive/DBMS Usage Documentation

None.

Page 25
None.

18. Glossary of Terms

APAR

ASCII

AVIRIS

BNSC

BOREAS

BORIS

CD-ROM

DAAC

EOS

EOSDIS

FFC

FPAR

GIS

GMT

GSFC

HTML

IFC

IPAR

LAI

NAD83

NASA

NSA

OBS

OJP

ORNL

PANP

PAR

PI

RSADU

RSS

SSA

TE

TRAC

URL

UTM

YA

YJP

19. List of Acronyms

- Absorbed Photosynthetically Active Radiation

- American Standard Code for Information Interchange

- Airborne Visible and Infrared Imaging Spectrometer

- British National Space Centre

- BOReal Ecosystem-Atmosphere Study

- BOREAS Information System

- Compact Disk-Read-Only Memory

- Distributed Active Archive Center

- Earth Observing System

- EOS Data and Information System

- Focused Field Campaign

- Fraction of absorbed Photosynthetically Active Radiation

- Geographic Information System

- Greenwich Mean Time

- Goddard Space Flight Center

- HyperText Markup Language

- Intensive Field Campaign

- Incident PAR

- Leaf Area Index

- North American Datum of 1983

- National Aeronautics and Space Administration

- Northern Study Area

- Old Black Spruce

- Old Jack Pine

- Oak Ridge National Laboratory

- Prince Albert National Park

- Photosynthetically Active Radiation

- Principal Investigator

- Remote Sensing Applications Development Unit

- Remote Sensing Science

- Southern Study Area

- Terrestrial Ecology

- Tracing Radiation and Architecture of Canopies

- Uniform Resource Locator

- Universal Transverse Mercator

- Young Aspen

- Young Jack Pine

Page 26
20. Document Information

20.1 Document Revision Dates

Written: 02-Aug- 1995

Last Updated: 30-Jul- 1999

20.2 Document Review Dates

BORIS Review: 10-Aug- 1998

Science Review: 03-Aug- 1998

20.3 Document ID

20.4 Citation

When using these data, please include the following acknowledgment as well as citations of

relevant papers in Section 17.2:

LAI-2000 and Ceptometer data were gathered by Dr. Stephen Plummer (British National Space

Centre/Remote Sensing Applications Development Unit) and Mr. Neil Lucas (University College of

Swansea).

If using data from the BOREAS CD-ROM series, also reference the data as:

Plummer, S. and P. Curran, "RSS-04: Coupling Remotely Sensed Data to Ecosystem Simulation

Models." In Collected Data of The Boreal Ecosystem-Atmosphere Study. Eds. J. Newcomer, D.

Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J. Nickeson, A. Papagno, D.

Rinker, R. Strub, T. Twine, F. Hall, and P. Sellers. CD-ROM. NASA, 2000.

Also, cite the BOREAS CD-ROM set as:

Newcomer, J., D. Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J.

Nickeson, A. Papagno, D. Rinker, R. Strub, T. Twine, F. Hall, and P. Sellers, eds. Collected Data of

The Boreal Ecosystem-Atmosphere Study. NASA. CD-ROM. NASA, 2000.

20.5 Document Curator

20.6 Document URL

Page 27
REPORT DOCUMENTATION PAGE FormApproved

OMB No. 0704-0188

Public reporting burden for this collection of informationis estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources,

gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this

collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson

Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503.

1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED

July 2000 Technical Memorandum

4. TITLE AND SUBTITLE

Technical Report Series on the Boreal Ecosystem-Atmosphere Study (BOREAS)

BOREAS RSS-4 1994 Southern Study Area Jack Pine LAI and FPAR Data

6. AUTHOR(S)

Stephen Plummer

Forrest G. Hall and Jaime Nickeson, Editors

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS (ES)

Goddard Space Flight Center

Greenbelt, Maryland 20771

9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS (ES)

National Aeronautics and Space Administration

Washington, DC 20546-0001

5. FUNDING NUMBERS

923

RTOP: 923-462-33-01

8. PEFORMING ORGANIZATION

REPORT NUMBER

2000-03136-0

10. SPONSORING / MONITORING

AGENCY REPORT NUMBER

TM--2000-209891

Vol. 49

11. SUPPLEMENTARY NOTES

S. Plummer: Institute for Terrestrial Ecology; J. Nickeson: Raytheon ITSS

12a. DISTRIBUTION / AVAILABILITY STATEMENT

Unclassifie_Unlimited

Subject Category: 43

Report available from the NASA Center for AeroSpace Information,

7121 Standard Drive, Hanover, MD 21076-1320. (301) 621-0390.

12b. DISTRIBUTION CODE

13. ABSTRACT (Maximum 200 words)

The RSS-4 team collected several data sets related to leaf, plant, and stand physical, optical, and

chemical properties. This data set contains leaf area indices and FPAR measurements that were taken

at the three conifer sites in the BOREAS SSA during August 1993 and at the jack pine tower flux and

a subset of auxiliary sites during July and August 1994. The measurements were made with LAI-2000

and Ceptometer instruments. The measurements were taken for the purpose of model parameterization

and to test empirical relationships that were hypothesized between biophysical parameters and remotely sensed data. The data are stored in tabular ASCII files.

14. SUBJECT TERMS

BOREAS, remote sensing science, FPAR measurements.

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