BOREAS RSS-04 1994 Jack Pine Leaf Biochemistry and Modeled Spectra in the SSA Summary The BOREAS RSS-04 team focused its efforts on deriving estimates of LAI and leaf chlorophyll and nitrogen concentrations from remotely sensed data for input into the Forest BGC model. This data set contains measurements of jack pine (Pinus banksiana) needle biochemistry from the BOREAS SSA in July and August 1994. The data contain measurements of current and year-1 needle chlorophyll, nitrogen, lignin, cellulose, and water content for the OJP flux tower and nearby auxiliary sites. The data have been used to test a needle reflectance and transmittance model, LIBERTY (Dawson et al., in press). The source code for the model and modeled needle spectra for each of the sampled tower and auxiliary sites are provided as part of this data set. The LIBERTY model was developed and the predicted spectral data generated to parameterize a canopy reflectance model (North, 1996) for comparison with AVIRIS, POLDER, and PARABOLA data. The data and model source code are stored in 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 Jack Pine Leaf Biochemistry and Modeled Spectra in the SSA 1.2 Data Set Introduction The needle biochemistry data set described here was obtained from the Southern Study Area (SSA) Old Jack Pine (OJP) (Pinus banksiana) site during Intensive Field Campaign (IFC)-2 in 1994 (19-Jul to 08-Aug-1994) of the BOReal Ecosystem- Atmosphere Study (BOREAS). The data were collected to help parameterize leaf and canopy reflectance and ecosystem simulation models. The data comprise measurements of current and year 1 needle chlorophyll, nitrogen, lignin, cellulose, and water content for tower and auxiliary sites located around the OJP flux tower. The needles were stripped from branches sampled from the upper canopy using a shotgun or, where the canopy was low, using clippers. Also included as part of this data set are the source code for the Leaf Incorporating Biochemistry Exhibiting Reflectance and Transmittance Yields (LIBERTY) model and modeled needle spectra for each of the sampled tower and auxiliary sites. The data set also contains needle spectral reflectance and transmittance for these samples generated using the LIBERTY model. LIBERTY is a leaf reflectance model developed as part of a doctoral thesis by Terry Dawson; a full description is available from references given in Section 17. A copy of the source code for version 1.1 of the software is available on request. See Section 14.2. 1.3 Objective/Purpose The Remote Sensing Science (RSS)-04 investigations were designed to obtain Leaf Area Index (LAI), fraction of absorbed Photosynthetically Active Radiation fPAR and foliar chemistry data for a complex, spatially variable forest canopy in order to: i) Parameterize an ecosystem simulation model. ii) Test empirical relationships hypothesized between biophysical variables and remotely sensed data. iii) Parameterize a forest reflectance model and compare it with Airborne Visible and Infrared Imaging Spectrometer (AVIRIS), Polarization and Directionality of Earth Reflectance (POLDER) and Portable Apparatus for Rapid Acquisitions of Bidirectional Observations of Land and Atmosphere (PARABOLA) data to deduce whether observed between canopy chemistry and reflectance are a product of canopy structure rather than foliar chemical variations themselves (see reference list, Section 17). iv) Drive the ecosystem simulation model with estimates of LAI and chemistry derived from remotely sensed data. 1.4 Summary of Parameters Variation in jack pine needle chemistry comprising: cellulose, chlorophyll, lignin, nitrogen, and water across the range (high, medium, low production) of auxiliary and tower sites. Needle reflectance and transmittance spectra were generated using the LIBERTY needle reflectance model (see references). 1.5 Discussion The measurements that comprise this data set were collected as a contribution to the determination of the biochemical characteristics of the BOREAS SSA. Such measurements were required to parameterize leaf and canopy reflectance models and as initial indicators of canopy state for use in ecosystem models such as FOREST-BGC. The data set provided here is curently experimental, for reasons described below and should be used in this context. 1.6 Related Data Sets BOREAS RSS-04 1994 Southern Study Area Jack Pine LAI and FPAR Data BOREAS RSS-07 LAI, Gap Fraction, and fPAR Data BOREAS TE-09 Photosynthetic Capacity and Foliage Nitrogen Data over the NSA 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 and transport, project supervision Section for Earth Observation Institute of Terrestrial Ecology Monks Wood Abbots Ripton Cambs,UK +44 1487 773381 +44 1487 773277 (fax) S.Plummer@ite.ac.uk *formerly Remote Sensing Applications Development Unit British National Space Centre Contact 2 ---------- Dr. Neil Lucas Role: data collection and transport School of Geography University of Kingston Kingston upon Thames Surrey, UK +44 181 547 7510 +44 181 547 7497 (fax) Contact 3 --------- Mr. Terry Dawson Role: sample processing and the LIBERTY model Doctoral student Department of Geography University of Southampton Highfields Southampton, UK Contact 4 --------- Jaime Nickeson Raytheon STX Corporation NASA GSFC Greenbelt, MD (301) 286-3373 (301) 286-0239 (fax) Jaime.Nickeson@gsfc.nasa.gov 3. Theory of Measurements For discussion of the LIBERTY leaf reflectance model, please see the series of papers by Dawson et al. 4. Equipment 4.1 Sensor/Instrument Description 4.1.1 Collection Environment Branch samples were collected in ambient atmospheric conditions during the sampling period. 4.1.2 Source/Platform All spectral measurements were made using laboratory facilities at the Universities of Southampton and New Hampshire. 4.1.3 Source/Platform Mission Objectives Not applicable. 4.1.4 Key Variables Concentrations (mass basis) of cellulose, chlorophyll, lignin, nitrogen, and water in current and >= 1-year-old needles. Infinite reflectance, single needle reflectance, and transmittance predicted using the LIBERTY needle reflectance model (see references). 4.1.5 Principles of Operation A Perkin-Elmer Lambda 19 spectrophotometer was used for ‘infinite reflectance’ measurements of fresh and dried ground jack pine needles as well as powdered samples of individual biochemicals. Infinite reflectance is the reflectance from a stack of needles of sufficient thickness that the addition of more needles does not change the reflectance. The Perkin-Elmer Lambda 19 spectrophotometer is a double-beam, double- monochromator, ratio recording spectrometer operating in the ultraviolet, visible, and near-infrared spectral ranges. The instrument was connected to an integrating sphere 60 mm in diameter. The two detectors consisted of (i) a side window photomultiplier for the visible wavelengths and (ii) a PbS detector for the near-infrared wavelengths. A prealigned tungsten-halogen lamp provided the illumination source. The reflectance spectra of samples were scanned over the 400-2500-nm wavelength interval with 1-nm increments. The spectral resolution varied between 1 to 2 nm in the 400-1000 nm wavelengths and from 4 to 5 nm in the middle infrared (1000-2500 nm). Calibration of the instrument was performed using internal radiometric and spectral calibration standards and a barium sulphate (BaSO4) standard. Instrumental corrections were performed as necessary, according to sample mounting and measurement type (Hosgood et al., 1994). Because water vapor absorbs radiation in the near-infrared range, the instrument was continually purged with nitrogen during measurements, the pressure being maintained at 3 to 4 bars. Measurements of single jack pine needle reflectance and transmittance spectra were made using a Zeiss Universal Microspectrophotometer (UMSP) 50 microscope that was linked to a computer for data acquisition and processing. Illumination was from a 100 W tungsten light with a color temperature of 3400 K. Depending upon the optical configuration, reflectance and transmittance measurements were taken at 1 nm steps over a wavelength range of 400-800 nm, individual values being determined from a mean of 16 measurements taken along the length of each needle and based upon a mean of 10 measurements taken at each sample point. A grating monochromator was used between the leaf specimen and the photometer with a slit width set to 10 nm. Measurements were made under an X20 dry objective with a measurement spot of approximately 500 micrometers being used, although this was varied to the largest possible area measurement of the leaf surface to maintain maximum homogeneity. Measurements were standardized against a didymium spectroscopy standard. Leaf biochemistry measurements were generated from needle samples obtained at 10 jack pine tower/auxiliary sites located in the vicinity of the SSA OJP and Young Jack Pine (YJP) Tower sites. Eight branch samples per site were obtained after sundown. The branchlets were immediately divided into current year and greater than 1-year-old needles and stored in polythene bags in cold boxes. The samples were then transferred to refrigerators at Paddockwood School. The branchlet samples were stripped of their needles and the needles weighed before transfer to a freezer to await shipping back to the UK. 4.1.6 Sensor/Instrument Measurement Geometry See Sections 4.1.1 and 4.1.5. 4.1.7 Manufacturer of Sensor/Instrument** Perkin-Elmer Analytical Instruments Seer Green Customer Centre Chalfont Rd, Seer Green Bucks HP9 2FX, UK (www.perkin-elmer.com) Carl Zeiss Ltd P.O. Box 78 Woodfield Rd Welwyn Garden City Herts AL7 1L, UK (www.zeiss.co.uk) ** Mention of company names or instruments does not indicate recommendation by the Natural Environment Research Council (NERC) or the University of Southampton. 4.2 Calibration Prediction of chemistry is dependent on known calibration standards provided by (for chlorophyll) the Aldrich Chemical Company (UK) and (for lignin, cellulose and nitrogen) developed by the University of New Hampshire (UNH). LIBERTY was developed specifically for conifer needles so the estimation of single leaf reflectance and transmittance spectra from stacked needles is possible. However, the program is equally valid for any leaf species with the minor caveat that the in-vivo absorption coefficients used were determined from empirical work on various pine species. 4.2.1 Specifications Calibration of the Perkin-Elmer instrument was performed using internal radiometric and spectral calibration standards and a BaSO4 standard. Instrumental corrections were performed as necessary, according to sample mounting and measurement type (Hosgood et al., 1994). Because water vapor absorbs radiation in the near-infrared range, the instrument was continually purged with nitrogen during measurements, the pressure being maintained at 3 to 4 bars. Measurements with the Zeiss instrument were standardized against a didymium spectroscopy standard. 4.2.1.1 Tolerance None given. 4.2.2 Frequency of Calibration None given. 4.2.3 Other Calibration Information Not applicable. 5. Data Acquisition Methods These leaf biochemistry measurements were generated from needle samples obtained at 10 jack pine tower/auxiliary sites located in the vicinity of the SSA OJP and YJP tower sites. The site codes are as follows: F5I6P* F7J0P F7J1P F8L6T (SSA-YJP tower) G1K9P G2L3T (SSA-OJP tower) G4K8P G7K8P G8L6P G9L0P *See Section 6.2, Field Notes. Samples were acquired from the upper tree canopy using either tree clippers (for young trees) or a large-bore shotgun for mature trees. Shotgun sampling was restricted to areas outside the wind aligned blob (WAB) for the two tower sites. Shotgun sampling in the upper canopy is more difficult than it seems, primarily because the shooting position can result in shoulder bruising from the recoil and because of the resistance of branches to falling. A number of shot types were assessed in the sampling and the most effective type for bringing down branches from the upper canopy proved to be 00 gauge, a compromise between large scatter and high velocity shot. Eight branch samples per site were obtained after sundown. The branchlets were immediately divided into current year and greater than 1-year-old needles and stored in polythene bags in cold boxes. The samples were then transferred to refrigerators at Paddockwood School. The branchlet samples were stripped of their needles and the needles weighed before transfer to a freezer to await shipping back to the UK. For shipping, the samples were sealed in polythene Ziploc bags in a cool box containing dry ice. Because of Federal Aviation Administration (FAA) regulations on transport of dry ice on passenger aircraft, the amount of dry ice used was restricted. On arrival in the UK, the samples were transferred to a large freezer facility at University of Wales, Swansea, and subsequently to a similar facility at the University of Southampton. 6. Observations 6.1 Data Notes None given. 6.2 Field Notes 02-Aug-1995 Site F5I6P not found. A sample site was thus established at 150 m in from Route 913 on a bearing of 59 degrees. 02-Aug-1995 Site F7J1P 60% Jack Pine, 20% Spruce, 20% Aspen. 02-Aug-1995 Site F7J0P 34% Jack Pine, 33% Spruce, 33% Aspen. 7. Data Description 7.1 Spatial Characteristics 7.1.1 Spatial Coverage The eight branch samples per site were a compromise between time/manpower and representativeness, particularly given that some of the auxiliary sites were not particularly uniform in terms of species. The coverage was also restricted to jack pine for the same reasons. The following site locations were sampled North American Datum of 1983 (NAD83): Site West North UTM UTM UTM Longitude Latitude Easting Northing Zone ----- ---------- -------- -------- --------- ---- F8L6T 104.64527 53.87581 523350.7 5969540.0 13 G2L3T 104.69203 53.91634 520257.0 5974035.0 13 F5I6P 105.11174 53.86608 492681.9 5968405.0 13 F7J0P 105.05116 53.88334 496666.7 5970320.0 13 F7J1P 105.03226 53.88211 497909.2 5970183.0 13 G1K9P 104.74810 53.90881 516576.8 5973183.0 13 G4K8P 104.76399 53.91884 515529.6 5974295.0 13 G7K8P 104.77147 53.95882 515023.9 5978742.0 13 G8L6P 104.63755 53.96558 523807.6 5979530.0 13 G9L0P 104.73778 53.97576 517227.6 5980634.0 13 7.1.2 Spatial Coverage Map Not available. 7.1.3 Spatial Resolution The data are point measurements at the given locations. 7.1.4 Projection Not applicable. 7.1.5 Grid Description Not applicable. 7.2 Temporal Characteristics 7.2.1 Temporal Coverage All the samples were collected from 25-Jul-1994 to 05-Aug-1994. 7.2.2 Temporal Coverage Map Not available. 7.2.3 Temporal Resolution These data represent the jack pine leaf chemistry during the 1994 growing season. 7.3 Data Characteristics Data characteristics are defined in the companion data definition file (rss4lib.def). 7.4 Sample Data Record Sample data format shown in the companion data definition file (rss4lib.def). 8. Data Organization 8.1 Data Granularity The Jack Pine Leaf Biochemistry and Modeled Spectra in the SSA Data are contained in three datasets. 8.2 Data Format(s) The chemistry data files contain numerical and character fields of varying length separated by commas. The character fields are enclosed within single apostrophe marks. There are no spaces between the fields. Sample data records are shown in the companion data definition file (rss4lib.def). Two additional files are included with this dataset and pertain to the LIBERTY model input and output, MODELED_SPECTRA.DAT and LIBERTY.ZIP. Predicted Spectra File: MODELED_SPECTRA.DAT The file contains numerical and character fields of varying length separated by commas. The file was generated with Macintosh Excel v5.0. The file contains nine header records followed by a series of data records. The nine header records are: Record 1: Filename, Number of Rows/Columns, PI-Names Record 2: Related data sets Record 3-7: Column names for the data in the file with a brief description Record 8: Plot name - data for each plot consist of three columns R, single refl, single trans Record 9: Column names for the data in the file delimited by commas Compressed within the file LIBERTY.ZIP file are eight files: liberty.c libinv.c lib_user.txt albino.dat pigment.dat water.dat ligcell.dat protein.dat For additional information about the ASCII files extracted from the LIBERTY.ZIP file and how they are used, see the lib_user.txt file (also extracted from the zip file). See also, section 9.3.2. 9. Data Manipulations 9.1 Formulae water(% dry) = (fresh weight - dry weight)/(dry weight) Chlorophyll-a = 9.93 A660 - 0.777 A642.5 Chlorophyll-b = 17.6 A642.5 - 2.81 A660 Total Chlorophyll = 7.12 A660 + 16.8 A642.5 where A660 and A642.5 refer to absorption at 660 and 642.5 nm, respectively. The nitrogen, lignin, and cellulose chemistry was derived using partial least- squares regression on the first difference of the spectral measurements. A full discussion of the approach and its comparison against stepwise multiple regression is given in Bolster et al. (1996). 9.1.1 Derivation Techniques and Algorithms Not applicable. 9.2 Data Processing Sequence 9.2.1 Processing Steps See Section 5 for preliminary information. a) Water The samples were removed from a deep freeze and weighed. Then they were frozen down to -30 °C and placed in a freeze-drier for 2 days. The samples were then reweighed and water content was calculated as a function of the dry mass: water(% dry) = (fresh weight - dry weight)/(dry weight) b) Chlorophyll For chlorophyll analysis, fresh samples were defrosted and then ground in a coffee grinder. Despite the delay between collection and processing, the fresh- cut samples were in excellent condition. Spectral reflectance of all 154 samples was measured using a Spectron S106 laboratory spectrometer. The chlorophyll was determined by wet chemical methods. Forty-six samples were selected by Mahalanobis distance from the mean to represent the spectral variation in the data set prescribed by the first difference of the spectral reflectance. Chlorophyll determination was conducted following the method of MacKinney (1941) and Lichtenthaler (1987) for three independent measurements per sample, making a total of 138 (46*3) individual values. The chlorophyll from ground freeze-dried samples was extracted in 90% acetone buffered with CaCO3. The concentration of chlorophyll-a and chlorophyll-b in the aliquot was then derived spectrophotometrically using the Spectron S106 calibrated against samples of spinach of known chlorophyll concentration obtained from the Aldrich Chemical Company, UK. Stepwise regression was conducted using five prediction wavelengths in the 400- 750-nm wavelength region to generate a prediction equation for the remaining samples. The correlation coefficients against chlorophyll-a, chlorophyll-b, and total chlorophyll were all greater than 0.92. Visual examination of the three separate predictions revealed large disparities in only two of the samples. These disparities were attributed to laboratory spectral measurement error and were revised. The resulting relationships were: Chlorophyll-a = 9.93 A660 - 0.777 A642.5 Chlorophyll-b = 17.6 A642.5 - 2.81 A660 Total Chlorophyll = 7.12 A660 + 16.8 A642.5 where A660 and A642.5 refer to absorption at 660 and 642.5 nm, respectively. The standard deviation between measurements of the same sample varied between 0.0237 to 0.6338 mg/g, with an average standard deviation of 0.201 mg/g. c) Nitrogen, Lignin, Cellulose The concentration of these three chemicals was derived for RSS-04 by UNH (Aber, Bolster, Martin). Ground, freeze-dried samples were dispatched to UNH, where they were reground using a Wiley Mill to increase particle size consistency. The samples were then scanned in an NIRSystems 6500 monochromator with a spinning cup module calibrated using a range of plant species, including Pinus resinosa and Pinus strobus. While jack pine (Pinus banksiana) is not in the calibration set, the predicted values fall well within the concentration ranges of the calibration data set. The chemistry was then derived using partial least-squares regression on the first difference of the spectral measurements. A full discussion of the approach and its comparison against stepwise multiple regression is given in Bolster et al. (1996). 9.2.2 Processing Changes None. 9.3 Calculations Estimated infinite reflectance, single-needle reflectance, and transmittance were calculated for each sample plot based on the plot average of measured chemical concentrations of needles. A full description of the LIBERTY model is given in the series of papers by Dawson et al. (see Section 17). 9.3.1 Special Corrections/Adjustments None, except see Dawson et al. for spectral estimation. 9.3.2 Calculated Variables 1. Predicted needle infinite reflectance spectra 2. Predicted single needle reflectance and transmittance spectra LIBERTY is a general-purpose radiative transfer model for predicting the reflectance and transmittance spectra of a leaf, or stack of leaves in the visible and near-infrared wavelengths (400-2500 nm). By treating a leaf as an aggregation of cells, with multiple radiation scattering between cells, output spectra is a function of three structural parameters and the combined absorption coefficients of leaf biochemicals. The user is prompted for input values, and the model output is written to an external file for use with graphing and spreadsheet packages as well as for coupling with vegetation canopy or ecosystem models. It is written in C and, using external absorption coefficient files, has been successfully compiled for the following platforms: MS-DOS SUN Microsystems Solaris Silicon Graphics IRIX No header or make files are required; all calls to external libraries and function definitions are made at the beginning of the program. LIBERTY was developed specifically for conifer needles, so the estimation of single leaf reflectance and transmittance spectra from stacked needles is possible. However, the program is equally valid for any leaf species with a minor caveat; the in-vivo absorption coefficients used were determined from empirical work on various pine species. LIBERTY uses external data files. This allows the user to easily modify the existing absorption coefficients or provide new ones. The required file list is: PIGMENT.DAT Absorption coefficient of in-vivo chlorophylls and carotenoids ALBINO.DAT Absorption coefficient of dried albino leaf due to lignin (visible wavelengths) WATER.DAT Water absorption coefficient LIGCELL.DAT Combined absorption coefficient of lignin and cellulose PROTEIN.DAT Protein absorption coefficient The following inputs are required from the user: -------------------------------------------------------------------------------- Variable Description Typical values (range) -------------------------------------------------------------------------------- Cell Diameter Average leaf cell diameter (1/m6) 40 (20-100) -------------------------------------------------------------------------------- Intercellular radiative flux passing between 0.045 (0.01-0.1) Determinant for the cells amount of air space -------------------------------------------------------------------------------- Leaf thickness Arbitrary value to determine single 1.6 (1-10) leaf reflectance and transmittance from infinite reflectance criteria -------------------------------------------------------------------------------- Baseline Wavelength compensate for changes in absolute Fresh: 0.0006 reflectance independent absorption Dry: 0.0004 to absorption -------------------------------------------------------------------------------- Albino Absorption in the visible region 2 (0-4) due to lignin absorption -------------------------------------------------------------------------------- Chlorophyll Chlorophyll (pigment) 200 (0-600) content content(mg/m2) -------------------------------------------------------------------------------- Water content Water content (g/m2) 100 (0-500) -------------------------------------------------------------------------------- Lignin and Combined lignin and cellulose 40 (10-80) Cellulose content content (g/m2) -------------------------------------------------------------------------------- Nitrogen content Nitrogen content (g/m2) 1 (0.3-2.0) -------------------------------------------------------------------------------- 9.4 Graphs and Plots None given. 10. Errors 10.1 Sources of Error Some error should be expected as a function of the delay in transferring samples from each site back to the UK. While every effort was made to limit this effect (sealed bags, refrigeration, darkness, CO2), the facilities/manpower were not available for onsite processing, particularly given the 'alternative-fund status' of RSS-04 involvement. 10.2 Quality Assessment 10.2.1 Data Validation by Source For a discussion of the accuracy of estimates of nitrogen, lignin and cellulose, please see Bolster et al. (1996) and reports to the NERC and National Aeronautics and Space Administration (NASA) Accelerated Canopy Chemistry Program (ACCP) by Curran, Kupiec and Smith (1994). Similarly, for a full discussion of the LIBERTY model and the assumptions of the model, please see the Dawson et al. series of papers. 10.2.2 Confidence Level/Accuracy Judgment None given. 10.2.3 Measurement Error for Parameters None given. 10.2.4 Additional Quality Assessments None given. 10.2.5 Data Verification by Data Center BOREAS staff has reviewed submitted data files, formats, and documentation for general consistency and content. 11. Notes 11.1 Limitations of the Data None given. 11.2 Known Problems with the Data None given. 11.3 Usage Guidance None given. 11.4 Other Relevant Information None given. 12. Application of the Data Set None given. 13. Future Modifications and Plans None given. 14. Software 14.1 Software Description Version 1.1 LIBERTY leaf reflectance and transmittance model. LIBERTY is a general-purpose radiative transfer model for predicting the reflectance and transmittance spectra of a leaf, or stack of leaves, in the visible and infrared wavelengths (400-2500 nm). By treating a leaf as an aggregation of cells, with multiple radiation scattering between cells, output spectra is a function of three structural parameters and the combined absorption coefficients of leaf biochemicals. The user is prompted for input values, and the model output is written to an external file for use with graphing and spreadsheet packages as well as for coupling with vegetation canopy or ecosystem models. It is written in C and, using external absorption coefficient files, has been successfully compiled for the following platforms: MS-DOS SUN Microsystems Solaris Silicon Graphics IRIX 14.2 Software Access Anyone wishing to register an interest in receiving updates to the LIBERTY code should contact Stephen Plummer at the e-mail address given in Section 2.3. See additional information regarding the LIBERTY model in Section 9.3.2. 15. Data Access 15.1 Contact Information Ms. Beth Nelson BOREAS Data Manager NASA GSFC Greenbelt, MD (301) 286-4005 (301) 286-0239 (fax) Elizabeth.Nelson@gsfc.nasa.gov 15.2 Data Center Identification See Section 15.1. 15.3 Procedures for Obtaining Data Users may place requests by telephone, electronic mail, or fax. 15.4 Data Center Status/Plans The RSS-04 leaf chemistry and spectral data are available from the Earth Observing System Data and Information system (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) The BOREAS contact at ORNL is: ORNL DAAC User Services Oak Ridge National Laboratory Oak Ridge, TN (423) 241-3952 ornldaac@ornl.gov ornl@eos.nasa.gov 16. Output Products and Availability 16.1 Tape Products None. 16.2 Film Products None. 16.3 Other Products American Standard Code for Information Interchange (ASCII) files containing leaf chemistry data and the LIBERTY output file produced by RSS-04 is available by contacting BOREAS Information System (BORIS) staff or online at the BOREAS Web site. The source code for LIBERTY is available by contacting BORIS staff and updates to the model can be obtained from Dr. Stephen Plummer (see Section 2.3) or through BORIS staff. 17. References 17.1 Platform/Sensor/Instrument/Data Processing Documentation Not applicable. 17.2 Journal Articles and Study Reports Bolster, K.L., M.E. Martin, and J.D. Aber, 1996. Determination of carbon fraction and nitrogen concentration in tree foliage by near-infrared reflectance - A comparison of statistical methods. Can. J. Forest. Res. 26,590-600. Curran, P.J. and J.A. Kupiec. 1994. The remote sensing of foliar chemistry Final Report to the Natural Environment Research Council. March 1994. Dawson, T.P., P.J. Curran, and S.E. Plummer. 1995. Modelling the spectral response of coniferous leaf structures for the estimation of biochemical concentrations. RSS'95. Rem. Sens. Soc. Nottingham, UK. 587-594. Dawson, T.P., P.J. Curran, and S.E. Plummer. 1996. A model approach to the biochemical analysis of coniferous forests from AVIRIS data. Proc. Second Int. Airborne Rem. Sens. Conf. ERIM. Ann Arbor, MI. Vol. I, 221-227. Dawson, T.P., Curran, P.J. and Plummer, S.E., 1996, LIBERTY - Towards the estimation of foliar biochemical concentration using high spectral resolution airborne sensors, RSS'96, Rem. Sens. Soc., Nottingham, UK, 79-86. Dawson, T.P., P.J. Curran, and S.E. Plummer. 1997. LIBERTY - modelling the effects of leaf biochemistry on reflectance spectra. Rem. Sens. Env. (in press). Hosgood, B., S. Jacquemoud, G. Andreoli, J. Verdebout, G. Pedrini, and G. Schmuck. 1995. Leaf optical properties experiment 93 (LOPEX93). Joint Research Centre European Commission publication no. EUR 16095 EN, Luxembourg. Kupiec, J.A. and P.J. Curran. 1994. The chemical and spectral variability in a slash pine canopy. Final Report to NASA Accelerated Canopy Chemistry (New Observations) Program. UNH Subcontract 93-20, Vol II. Lichtenthaler, H.K. 1987. Chlorophylls and caroteinoids: pigments of photosynthetic biomembranes. Methods in Enzymology. 148, 350-382. Mackinney, G. 1941. Absorption of light by chlorophyll solutions. J. Biol. Chem. 140, 315-322. North, P.R. 1996. A three-dimensional forest light interaction model using a Monte-Carlo method. IEEE Trans. Geosci. and Rem. Sens. 34, 946-956. North, P.R. and S.E. Plummer. 1994. Estimation of conifer bi-directional reflectance using a Monte Carlo method. IGARSS'94, IEEE. Piscataway, NJ. Vol. I, 114-116. North, P.R., S.E. Plummer, D.W. Deering, and Leroy, M. 1996. Validation of a BRDF model for boreal forest. IGARSS'96, IEEE. Piscataway, NJ. Vol.III, X, 1654- 1656. Sellers P.J, and F.G. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1994-3.0 NASA BOREAS Report (EXPLAN 94). Sellers P.J., F.G. Hall, H. Margolis, B. Kelly ,D. Baldocchi ,G. den Hartog, J. Cihlar, M.G. Ryan, B. Goodison, P. Crill, K.J. Ranson, D. Lettenmaier, and D.E. Wickland. 1995. The boreal ecosystem-atmosphere study (BOREAS): an overview and early results from the 1994 field year. Bulletin of the American Meteorological Society, 76, 1549-1577. Sellers P.J., F.G. Hall, and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994 Operations. NASA BOREAS Report (OPS DOC 94). Sellers P.J., and F.G. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1996-2.0 NASA BOREAS Report (EXPLAN 96). Sellers P.J., F.G. Hall, and K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere Study: 1996 Operations. NASA BOREAS Report (OPS DOC 96). 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, and F.E. Guertin. (1997). "BOREAS in 1997: Experiment Overview, Scientific Results and Future Directions", Journal of Geophysical Research (JGR), BOREAS Special Issue, 102(D24), Dec. 1997, pp. 28731-28770. 17.3 Archive/DBMS Usage Documentation None. 18. Glossary of Terms None given. 19. List of Acronyms ACCP - Accelerated Canopy Chemistry Program ASCII - American Standard Code For Information Interchange AVIRIS - Airborne Visible and InfraRed Imaging Spectrometer BGC - Biogeochemistry BNSC - British National Space Centre BOREAS - BOReal Ecosystem Atmosphere Study BORIS - BOREAS Information System DAAC - Distributed Active Archive Center EOS - Earth Observing System EOSDIS - EOS Data and Information System FAA - Federal Aviation Administration fPAR - Fraction of absorbed Photosynthetically Active Radiation GMT - Greenwich Mean Time GSFC - Goddard Space Flight Center IFC - Intensive Field Campaign ITE - Institute of Terrestrial Ecology LAI - Leaf Area Index LIBERTY - Leaf Incorporating Biochemistry Exhibiting Reflectance and Transmittance Yields NAD83 - znorth American Datum of 1983 NASA - National Aeronautics and Space Administration NERC - Natural Environment Research Council (UK) NSA - Northern Study Area OBS - Old Black Spruce OJP - Old Jack Pine ORNL - Oak Ridge National Laboratory PANP - Prince Albert Nationa Park PAR - Photosynthetically Active Radiation PARABOLA- Portable Apparatus for Rapid Acquisition of Bidrectional Observations of Land and Atmosphere PI - Principal Investigator POLDER - Polarization and Directionality of Earth Rdiance RSADU - Remote Sensing Applications Development Unit RSS - Remote Sensing Science SSA - Southern Study Area UMSP - Universal Microspectrophotometer UNH - University of New Hampshire URL - Uniform Resource Locator UTM - Universal Transverse Mercator WAB - Wind-Aligned Blob YJP - Young Jack Pine 20. Document Information 20.1 Document Revision Date Written: 07-Jan-1997 Last updated: 14-Sep-1998 20.2 Document Review Date(s) BORIS Review: 09-Sep-1998 Science Review: 15-Jul-1998 20.3 Document ID 20.4 Citation Data: Leaf chemistry data were gathered by Dr. Stephen Plummer (Institute of Terrestrial Ecology) and Dr. Neil Lucas (University of Kingston) and processed at the Universities of Southampton and New Hampshire under the direction of Terry Dawson (University of Southampton). Model Spectra: The LIBERTY model and associated spectra were generated as part of a doctoral study by Mr. Terry Dawson (University of Southampton). 20.5 Document Curator 20.6 Document URL Keywords: Leaf Chemistry Chlorophyll Lignin Cellulose Modeled Spectra RSS04_Leaf_Chem_Liberty.doc 09/14/98