BOREAS TE-10 Leaf Chemistry Data Summary The BOREAS TE-10 team collected several data sets in support of its efforts to characterize and interpret information on the reflectance, transmittance, gas exchange, chlorophyll content, carbon content, hydrogen content, and nitrogen content of boreal vegetation. This data set describes the relationship between sample location, age, chlorophyll content, and C-H-N concentrations at several sites in the SSA conducted during the growing seasons of 1994 and 1996. The data are stored in tabular ASCII files. Table of Contents 1 Data Set Overview 2 Investigators 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 Modification 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 TE-10 Leaf Chemistry Data 1.2 Data Set Introduction This data set describes the relationship between sample location, age photosynthetic pigments (Chlorophyll A (chla), Chlorophyll B (chlb), and Carotenoid (carot)) and foliar Carbon-Hydrogen-Nitrogen (C-H-N) concentrations in canopies from the BOReal Ecosystem-Atmosphere Study (BOREAS) Southern Study Area (SSA) - Old Black Spruce (SSA-OBS), Old Jack Pine (SSA-OJP), Young Jack Pine (SSA-YJP), Old Aspen (SSA-OA), Old Aspen Auxiliary (OA-AUX), Young Aspen (YA), and Young Aspen Auxiliary (YA-AUX) sites. Chlorophyll pigments and foliar C-H-N concentrations were examined as part of an effort to characterize differences between species, seasons (spring, summer, and fall), stand age, leaf position, and age at the BOREAS SSA sites. Samples were taken at seven locations in the SSA: SSA-OBS, SSA-OJP, YJP, YA, YA-AUX, OA-AUX) and SSA-OA during each of the three Intensive Field Campaigns (IFCs) in 1994. Samples were taken at five locations in the SSA: SSA-OBS, SSA-OJP, YJP, YA-AUX, and OA-AUX during each of the three seasons in 1996. This information will be useful for understanding variation in the gas exchange rates. Measurements of chlorophyll and C-H-N concentration were made in the laboratory. A spectrophotometer was used to assess chlorophyll content and a Carbon- Hydrogen-Nitrogen-600 (CHN-600) Elemental Analyzer system was used to obtain foliar C-H-N concentrations. 1.3 Objective/Purpose The purposes of this work were to: 1) Obtain a canopy profile of chlorophyll absorptance and C-H-N concentrations. 2) Examine interspecific and interseasonal differences in these parameters. 3) Relate these differences to the photosynthetic measurements. 1.4 Summary of Parameters Each data record includes the chla, chlb, carot, C/N ratio, C, N, and H. 1.5 Discussion Chlorophyll pigment absorptances and C-H-N concentrations were measured in the laboratory on the dominant broadleaf and coniferous woody plant species growing at SSA-OBS (Picea mariana and Larix laricina), SSA-OJP (Pinus banksiana and Apocynum androsaemifolium), SSA-YJP (Pinus banksiana), YA (Populus tremuloides and Corylus cornuta Marsh), and YA-AUX (Populus tremuloides, Corylus cornuta Marsh, and Picea glauca), and the sites SSA-OA and OA-AUX (Populus tremuloides and Corylus cornuta Marsh) in the SSA of the boreal forest. Dogbane (Apocynum androsaemifolium) was an understory species at the SSA-OJP site. Tamarack (Larix laricina) was another species located at SSA-OBS, and hazelnut (Corylus cornuta Marsh) was an understory species at YA, YA-AUX, OA,and OA-AUX. Picea glauca was collected as a cospecies at the YA-AUX site. 1.6 Related Data Sets BOREAS TE-09 NSA Leaf Chlorophyll Density BOREAS TE-09 NSA Photosynthetic Capacity and Foliage Nitrogen Data BOREAS TE-09 PAR and Leaf Nitrogen Data for NSA Species BOREAS TE-10 Leaf Optical Properties 2. Investigator(s) 2.1 Investigator(s) Name and Title Dr. Elizabeth Middleton, Project Scientist Dr. Joseph Sullivan, Assistant Professor 2.2 Title of Investigation CO2 and Water Fluxes in the Boreal Forest Overstory: Relationship to fAPAR and Vegetation Indices for Needles/Leaves 2.3 Contact Information Contact 1: Elizabeth M. Middleton, Ph.D. Biospheric Sciences Branch NASA GSFC Greenbelt, MD (301) 286-8344 (301) 286-0239 (fax) betsym@ltpsun.gsfc.nasa.gov Contact 2: Joe H. Sullivan, Ph.D. Department of Natural Resource Sciences and Landscape Architecture University of Maryland College Park, MD (301) 405-1626 (301) 314-9308 (fax) botn9@umdd.umd.edu Contact 3: Andrea Papagno Raytheon STX Corporation NASA GSFC Greenbelt, MD (301) 286-3134 (301) 286-0239 (fax) apapagno@pop900.gsfc.nasa.gov Contact 4: Shelaine Curd Raytheon STX Corporation NASA GSFC Greenbelt, MD (301) 286-2447 (301) 286-0239 (fax) shelaine.curd@gsfc.nasa.gov 3. Theory of Measurements Photosynthetic pigment concentrations were calculated using established equations that estimate concentration as a function of absorptance of foliar extracts at specific wavelengths. C and H were determined by infrared analysis of the combusted sample. N was determined by thermal conductivity. 4. Equipment 4.1 Sensor/Instrument Description CHN-600 Elemental Analyzer System 785-500 (LECO Corp., St. Joseph, MI). LI-COR Area Meter (LI-COR, Inc., Lincoln, Nebraska). In 1994, a Beckman DU-600 spectrophotometer was used in the laboratory at the University of Saskatchewan to determine chlorophyll absorptance. In 1994 and 1996, a Perkin-Elmer Lambda 3 Double Beam Spectrophotometer was used in the laboratory at the Beltsville Agricultural Research Center (BARC) to determine chlorophyll absorptance. 4.1.1 Collection Environment The vertical profile of the canopy was divided into three layers: top, middle, and bottom. White spruce (Picea glauca) and tamarack (Larix laricina) had only one top layer measured. White spruce was located at YA-AUX. Tamarack was an understory species at the SSA-OBS. At SSA-OA and YA sites, there was a hazelnut (Corylus cornuta Marsh) understory that was measured during each IFC in 1994. At the SSA-OJP, the understory species dogbane (Apocynum androsaemifolium) was measured during IFC-2 in 1994. Gas exchange measurements and sample collections were made from platform canopy access towers constructed onsite by BOREAS staff at the SSA-OBS, OA, OA-AUX, and SSA-OJP sites, and from the ground at the YJP, YA, and YA-AUX sites. Data were obtained during three discrete measurement periods (one to two measurement days each period) designated as the spring, summer, and fall seasons (IFC-1, -2, and -3). These seasons were selected to measure parameters at bud break and leaf expansion (24-May-1994 to 12-Jun-1994 and 21-April-1996 to 24-June-1996), during midsummer or peak growing season (26-Jul-1994 to 08-Aug-1994 and 10-July-1996 to 17-July-1996), and at the onset of dormancy and senescence in autumn (30-Aug- 1994 to 15-Sept-1994 and 20-October-1996 to 31-October-1996). Measurements were made on leaves and needles from the upper, middle, and lower canopy sections of the trees adjacent to the canopy access towers at SSA-OJP, SSA-OA, OA-AUX, and SSA-OBS, and on the young trees present near the flux tower sites at SSA-YJP, YA, and YA-AUX. For Pinus banksiana, measurements were made on each needle class present. In the 1994 measurement year, needle age classes measured were 1994, 1993, and 1992. In the 1996 measurement year, needle age classes measured were 1996, 1995, and 1994. For Picea glauca, age classes 1 (1994) and 2 (1993) were measured in 1994. In 1996, age classes 1 (1996) and 2 (1995) were measured for Picea glauca. In 1994, for Picea mariana, the newest age class (1994 needles) was measured alone, while needles 2 and 3 years old (1993 and 1992 needles) were combined in one measurement, as were 4 and 5 year old needles (1991 and 1990 needles). In 1996, for Picea mariana, the newest age class (1996 needles) was measured alone, while needles 2 and 3 years old (1995 and 1994 needles) were combined in one measurement, as were 4 and 5 year old needles (1993 and 1992 needles). At least eight replicate measurements and sample collection per season, canopy location, and age group were made for each species. These activities took place on trees that were accessible from the canopy access towers (approximately four trees, with two upper and lower branches measured per tree) at the SSA-OBS, SSA- OJP, OA_AUX, and SSA-OA sites and on the same number of trees each season at the SSA-YJP, YA, and YA-AUX sites. Sample leaves and stems with needles were sealed in plastic bags with moist towels and placed on ice for transport to the laboratory for further analysis. The laboratory was provided by BOREAS staff in Paddockwood, Saskatchewan (SK), approximately 60 km from the research sites. Each sample was divided into two components, with one portion used for measurement of oxygen evolution (1994 only) and photosynthetic pigments, and the remaining material used for analysis of leaf optical properties and N content. At the laboratory, samples were stored in the dark in the refrigerator until they were measured. Laboratory measurements included quantitative properties, oxygen evolution (1994 only), and optical properties. A foliar disk sample 2.73 cm in diameter was taken from each of the broadleaf samples for optical properties and then placed in a closed vial of dimethyl sulfoxide (DMSO) in the dark. A mass of needles, 10-20 count, chopped, was taken from the conifers for optical properties and then placed in a closed vial of DMSO in the dark. The sample pieces remained in DMSO until all of the photosynthetic pigments had been extracted. The rest of the samples were dried in an oven at 70 °F for three days. The samples in DMSO were of a known weight (grams) and/or hemisurface area (cm2). The dried samples were weighed in grams using a balance and then transported to the Maryland Soils Laboratory. In 1994, after the chlorophyll was extracted in IFC-1, the chlorophyll absorptances were measured at the spectrophotometer lab at the University of Saskatchewan, Canada. The drained tissue samples were dried in an oven at 70 °F for three days and then weighed in grams. During IFCs-2 and -3 in 1994, and in 1996 , the DMSO sample vials were transported to the United States Department of Agriculture (USDA) lab in Beltsville, Maryland. The drained tissue samples were dried in an oven at 70 °F for three days and then weighed in grams. In 1994: Absorptance was measured at 470 nm, 640 nm, 648 nm, and 750 nm with a dual-beam spectrophotometer (Beckman DU-600 or Perkin-Elmer Lambda 3) for the calculation of chlorophyll and carotenoid concentrations by the equations of Lichtenthaler (1987) modified for DMSO by Chappelle and Kim (1992). Chemical analysis of tissue C-H-N was conducted at the University of Maryland by the Maryland Soil Testing Laboratory using a CHN-600 Elemental Analyzer System (LECO Corp., St. Joseph, MO). chl formula: chla = 12.15 A664 nm - 2.79 A648 nm (1) chlb = 21.5 A648 nm - 5.1 A664 nm (2) carot = (1000 A470 nm - 1.82 chla - 85.02 chlb)/198 (3) where A nm = absorptance at the specified wavelength Refer to Lichtenthaler, 1987, and Chappelle and Kim, 1992, in the reference section. Spectral absorptances were measured at several wavelengths (700, 664, 648, and 470 nm) and used in these equations (Lichtenthaler, 1987 and Chappelle and Kim, 1992) to calculate pigment content for chla, chlb, and carot. These formulae calculate pigment content as µg/ml, assuming 1 ml of solvent for the pigment extraction. Pigment content expressed as µg/cm2 was determined by multiplying these values by a factor made up of the actual volume of the extraction divided by the one-sided projected leaf area of the sample (e.g., 4 ml/2.5 cm2). When expressed on the basis of sample dry weight, the correction factor was the actual volume of the extraction divided by the sample dry weight (e.g., 4 ml/0.025 g). Values were reported to the BOREAS Information System (BORIS) as either µg/cm2 (broadleaves, some conifers) or mg/g (conifers). In 1996: Absorptance was measured at several wavelengths (750, 674, 646, 510, 490, and 470 nm) with a dual-beam spectrophotometer (Beckman DU-600 or Perkin-Elmer Lambda 3) for the calculation of chlorophyll (chl) and carotenoid concentrations by the equations of Lichtenthaler (1987) modified for DMSO by Chappelle and Kim (1992). Chemical analysis of tissue CHN was conducted at the University of Maryland by the Maryland Soil Testing Laboratory using a C-H-N-600 Elemental Analyzer System (LECO Corp., St. Joseph, MO). chl formula: chla = 22.9422 A674 nm (4) chlb = 25.30382 A646 nm - 16.1909 A674 nm (5) carot = (1000 A470 nm - 1.82 chla- 85.02 chlb)/198 (6) where A nm = absorptance at the specified wavelength Refer to Lichtenthaler, 1987, and Chappelle and Kim, 1992, in the reference section. Spectral absorptances were measured at several wavelengths (750, 674, 646, 510, 490, and 470 nm) and used in these equations (Lichtenthaler, 1987, and Chappelle and Kim, 1992) to calculate pigment content for chla, chlb, and carotenoid. These formulae calculate pigment content as µg/ml, assuming 1 ml of solvent for the pigment extraction. Pigment content expressed as µg cm-2 was determined by multiplying these values by a factor made up of the actual volume of the extraction divided by the one-sided projected leaf area of the sample (e.g., 4 ml/2.5 cm2). When expressed on the basis of sample dry weight, the correction factor was the actual volume of the extraction divided by the sample dry weight (e.g., 4 ml/0.025 g). Values were reported to BORIS as either µg/cm2 (broadleaves, some conifers) or mg/g (conifers). Chemical analysis of tissue C-H-N was conducted at the University of Maryland. by the Maryland Soil Testing Laboratory using a CHN-600 Elemental Analyzer System (LECO Corp., St. Joseph, MO). At the soils laboratory, the dried samples were ground. A coffee mill was used to grind the conifer samples. A mortar and pestle were used to grind the broadleaf samples. To have enough sample mass to perform the C-H-N measurements, some samples had to be combined with other samples from different trees, but of the same age class. These combined samples are shown in the data file. Samples were weighed using an analytical balance, and then processed in the Elemental Analyzer. C-H-N concentrations in each sample were expressed as a percentage of the sampled mass. 4.1.2 Source/Platform Samples were taken from towers except at SSA-YJP, SSA-YA, and SSA-YA-AUX, and were cut using knives. Chlorophyll absorptances and C-H-N concentrations were measured in the laboratory. 4.1.3 Source/Platform Mission Objectives The towers were constructed to supply a means of accessing the tree canopies. 4.1.4 Key Variables Chla, Chlb, and carot per gram dry weight Chla, Chlb, and carot per centimeter squared (cm2) hemisurface area C/N ratio C, H, and N milligrams (mg) per gram (g) dry weight Pigment content was reported as either mg/g or µg/cm2 unless both values were obtained. 4.1.5 Principles of Operation Photosynthetic pigment concentrations were calculated using established equations (see Section 4.1.1, equations 1-6) that estimate concentration as a function of absorptance of foliar extracts at specific wavelengths. Carbon and hydrogen were determined by infrared analysis of the combusted sample. Nitrogen was determined by thermal conductivity. 4.1.6 Sensor/Instrument Geometry All instrumentation took place under laboratory conditions. 4.1.7 Manufacturer of Sensor/Instrument Beckman DU Series 600 Spectrophotometer Beckman Instruments Laboratory Automation Operations 90 Boroline Road Allendale, NJ 07401 (201) 818-8900 (201) 818-9740 (fax) CHN-600 Elemental Analyzer System 785-500 LECO Corporation St. Joseph, MI USA LI-COR Area Meter For 1994: Model Number 3100 For 1996: Model Number 3000A, Portable LI-COR, Inc. 4421 Superior Street P.O. Box 4425 Lincoln, NE 68504-0425 USA (402) 467-3576 (402) 467-2819 (fax) Perkin Elmer Lambda 3 Double-Beam Spectrophotometer Perkin-Elmer Corp. 761 Main Avenue Norwalk, CT 06859 USA 1 (800) 762-4000 4.2 Calibration The C-H-N analyzer was calibrated at the start of every day. The spectrophotometer was calibrated between each sample run against a blank standard which was a quartz cuvette filled with the solvent (DMSO). The leaf area meter was calibrated before each use with a 10 cm disk. Measurements of weight (mass) were reset to zero before each sample reading. 4.2.1 Specifications The weighing balance was accurate to 0.01 g. The analytical balance was accurate to 0.0001 g. The leaf area meter was accurate to within 1.00 %. 4.2.1.1 Tolerance No tolerance level was set. 4.2.2 Frequency of Calibration The spectrophotomter was calibrated between each sample run. The leaf area and balances were calibrated every time they were turned on, two to four times a day. The CHN analyzer was calibrated at the start of every day of measurement. 4.2.3 Other Calibration Information None. 5. Data Acquisition Methods On the towers at OA, OA-AUX, SSA-OBS, SSA-YJP, and SSA-OJP, top samples were taken from the top tower level, middle samples from the middle level, and bottom samples from the bottom tower level. At YA-AUX and YA, top samples were taken from the upper 1/3, middle samples from the middle 1/3, and bottom samples from the lower 1/3 part of the trees. At white spruce, only a top layer was sampled. At SSA-OJP, there was a dogbane (Apocynum androsaemifolium) understory during IFC-2 in 1994. AtOA and YA, there was a hazelnut (Corylus cornuta Marsh) understory. At SSA-OBS, there was a tamarack (Larix laricina) understory. Stems (with needles) and leaf samples were harvested from each layer and immediately placed within a plastic bag that also contained a moist towel. For transport to the laboratory, the bags were placed in a cooler. For black spruce, age classes 1, 2 and 3 were separated from ages 4 and 5, until analysis was performed at the laboratory. For jack pine, age classes 1, 2, and 3 were separated in the field before being brought to the laboratory. For white spruce, age class 1 was separated from age classes 2 and 3, which were separated from 4 and 5. Petiols were kept on all the broadleaves. At the laboratory, samples were stored in the dark in the refrigerator until they were measured. 6. Observations Nothing out of the ordinary. 6.1 Data Notes None. 6.2 Field Notes None. 7. Data Description 7.1 Spatial Characteristics 7.1.1 Spatial Coverage At the SSA-OJP, SSA-OBS, OA, and OA-AUX tower sites, branch samples were taken from trees within reach from all sides of the towers. There were no towers at the other sites. At each site, at least five trees that had the required layers for that site. The SSA measurement sites and associated North American Datum of 1983 (NAD83) coordinates are: OA canopy access tower located 100 m up the path to the flux tower site, site id C3B7T, Lat/Long: 53.62889° N, 106.19779° W, Universal Transverse Mercator (UTM) Zone 13, N:5,942,899.9 E:420,790.5. OA-AUX canopy access tower located by the trailhead/parking area for the path leading to the flux tower at site id C3B7T, Lat/Long: 53.62889° N, 106.19779° W, UTM Zone 13, N:5,942,899.9 E:420,790.5 This OA-AUX site was farther up the path than SSA-OA from the flux tower site. SSA-OBS canopy access tower located at the flux tower site, site id G8I4T, Lat/Long: 53.98717° N, 105.11779° W, UTM Zone 13, N:5,982,100.5 E;492,276.5. SSA-OJP canopy access tower flux tower site, site id G2L3T, Lat/Long: 53.91634° N, 104.69203° W, UTM Zone 13, N:5,974,257.5 E:520,227.7. YA canopy access tower, site id D0H4T, Lat/Long: 53.65601° N, 105.32314° W, UTM Zone 13, N:5,945,298.9, E:478,644.1. YA-AUX, site id D6H4A, Lat/Long: 53.708° N, 105.315° W, UTM Zone 13, N:5,951,112.1, E:479,177.5. SSA-YJP flux tower site, site id F8L6T, Lat/Long: 53.87581° N, 104.64529° W, UTM Zone 13, N:5,969,762.5 E:523,320.2. Please note that at SSA YA-AUX, black spruce, jack pine, aspen, balsam fir, balsam poplar, tamarack, hazelnut, were present and several other shrub and herbaceous species. 7.1.2 Spatial Coverage Map Not available. 7.1.3 Spatial Resolution These data are point source 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 Samples were collected from the field every day from 8 a.m. 3 p.m. An independent data set was taken at each of the field campaigns in 1994 and 1996. The specific dates for each collection of samples are given in the data table. 7.2.2 Temporal Coverage Map Site Species Sample Dates (1994) IFC-1 IFC-2 IFC-3 SSA-OBS black spruce 01-JUN 28-JUL to 01-AUG 13-SEP SSA-OA-AUX aspen 03-AUG 02-SEP SSA-OA-AUX hazelnut 03-AUG 02-SEP SSA-OJP jack pine 31-MAY 25-JUL 06-SEP SSA-OJP dogbane 25-JUL SSA-OA aspen 30-MAY,11-JUN 21-JUL 15-SEP SSA-OASP hazelnut 26-MAY,11-JUN 21-JUL 15-SEP SSA-YA-AUX aspen 25-MAY SSA-YJP jack pine 26-MAY,07-JUN 22-JUL to 23-JUL 08-SEP SSA-YA-AUX white spruce 31-JUL to 01-AUG 11-SEP SSA-YA aspen 04-JUN 30-JUL 02-SEP,12-SEP SSA-YA hazelnut 04-JUN 30-JUL 02-SEP,12-SEP Site Species Sample Dates (1996) Spring Summer Fall SSA-OBS black spruce 10-MAY 14-JUL 11-OCT SSA-OBS black spruce 19-JUN SSA-OBS black spruce 21-JUN SSA-OBS tamarack 17-JUL 10-OCT SSA-OJP jack pine 18-JUN 11-JUL 13-OCT SSA-OJP jack pine 23-JUN SSA-OA-AUX aspen 24-JUN 17-JUL SSA-OA-AUX hazelnut 24-JUN 17-JUL SSA-YJP jack pine 8-MAY TO 9-MAY 12-JUL 12-OCT SSA-YJP jack pine 23-JUN 15-JUL SSA-YA-AUX white aspruce 8-MAY 10-JUL 10-OCT SSA-YA-AUX white aspruce 20-JUN 7.2.3 Temporal Resolution In general each site was sample multiple times at irregular intervals during the year. 7.3 Data Characteristics Data characteristics are defined in the companion data definition file (te10lfch.def). 7.4 Sample Data Record Sample data format shown in the companion data definition file (te10lfch.def). 8. Data Organization 8.1 Data Granularity The Leaf Chemistry Data are contained in three datasets. 8.2 Data Format(s) The data files contain numerical and character fields of varying length separated by commas. The character fields are enclosed with a single apostrophe marks. There are no spaces between the fields. Sample data records are shown in the companion data definition file (te10lfch.def). 9. Data Manipulations 9.1 Formulae 1994 chl formula: chla = 12.15 A664 nm - 2.79 A648 nm chlb = 21.5 A648 nm - 5.1 A664 nm carot = (1000 A470 nm - 1.82 chla - 85.02 chlb)/198 where A nm = absorptance at the specified wavelength Refer to Lichtenthaler, 1987, and Chappelle and Kim, 1992, in the reference section. Spectral absorptances were measured at several wavelengths (700, 664, 648, and 470 nm) and used in these equations (Lichtenthaler, 1987, and Chappelle and Kim, 1992) to calculate pigment content for chla, chlb, and carot. These formulae calculate pigment content as µg/ml, assuming 1 ml of solvent for the pigment extraction. Pigment content expressed as µg/cm2 was determined by multiplying these values by a factor made up of the actual volume of the extraction divided by the one-sided projected leaf area of the sample (e.g., 4 ml/2.5 cm2). When expressed on the basis of sample dry weight, the correction factor was the actual volume of the extraction divided by the sample dry weight (e.g., 4- ml/0.025-g). Values were reported to BORIS as either µg/cm2 (broadleaves, some conifers) or mg/g (conifers). 1996 chl formula: chla = 22.9422 A674 nm chlb = 25.30382 A646 nm - 16.1909 A674 nm carot = (1000 A470 nm - 1.82 chla - 85.02 chlb)/198 where A nm = absorptance at the specified wavelength Refer to Lichtenthaler, 1987, and Chappelle and Kim, 1992, in the reference section. Spectral absorptances were measured at several wavelengths (750, 674, 646, 510, 490, and 470 nm) and used in these equations (Lichtenthaler, 1987, and Chappelle and Kim, 1992) to calculate pigment content for chla, chlb, and carotenoid. These formulae calculate pigment content as µg/ml, assuming 1 ml of solvent for the pigment extraction. Pigment content expressed as µg cm-2 was determined by multiplying these values by a factor made up of the actual volume of the extraction divided by the one-sided projected leaf area of the sample (e.g., 4 ml/2.5 cm2). When expressed on the basis of sample dry weight, the correction factor was the actual volume of the extraction divided by the sample dry weight (e.g., 4 ml/0.025 g). Values were reported to BORIS as either µg/cm2 (broadleaves, some conifers) or mg/g (conifers). 9.1.1 Derivation Techniques and Algorithms See Section 9.1. 9.2 Data Processing Sequence 9.2.1 Processing Steps Data were recorded automatically by a computer and printed on a printer or saved to a diskette. Subsequent calculations were performed using Quattro Pro 6.0 for Windows 3.1. 9.2.2 Processing Changes None. 9.3 Calculations See Section 9.1. 9.3.1 Special Corrections/AdJustments None. 9.3.2 Calculated Variables See Section 9.1. 9.4 Graphs and Plots None. 10. Errors Errors are primarily caused by variation in researcher measurement techniques and in instrumentation. The data have received a quality review by Terrestrial Ecology (TE)-10 personnel, and the errors have been removed. 10.1 Sources of Error Errors are primarily caused by variation in researcher measurement techniques, the acquisition of measurements by multiple persons, and instrumentation variation. The data have received a quality review by TE-10 personnel, and all known sources of calculation errors have been corrected. 10.2 Quality Assessment Data have received a quality review by TE-10 personnel. 10.2.1 Data Validation by Source Comparisons were made with other BOREAS results and with published results. 10.2.2 Confidence Level/Accuracy Judgment None available, but it is felt that these data are accurate. 10.2.3 Measurement Error for Parameters Not available. 10.2.4 Additional Quality Assessments Calculated results were plotted, and the plots were compared with those from published papers. 10.2.5 Data Verification by Data Center Data were examined for general consistency and clarity. 11. Notes 11.1 Limitations of the Data None. 11.2 Known Problems with the Data None. 11.3 Usage Guidance None. 11.4 Other Relevant Information None. 12. Application of the Data Set These data can be used to assess the relationship between sample location, sample age, chlorophyll content, and C-H-N concentrations. 13. Future Modifications and Plans None. 14. Software 14.1 Software Description Calculations were performed using Quattro Pro 6.0 for Windows 3.1. This document was prepared using Microsoft Word 5.1a and 6.0 for the Macintosh and Microsoft Word 6.0 for Windows. 14.2 Software Access Contact the commercial vendors. 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 TE-10 leaf chemistry data are available from the EOSDIS ORNL DAAC (Earth Observing System Data and Information System) (Oak Ridge National Laboratory) (Distributed Active Archive Center). The BOREAS contact at ORNL is: ORNL DAAC User Services Oak Ridge National Laboratory (865) 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 Tabular American Standard Code for Information Interchange (ASCII) files. 17. References 17.1 Platform/Sensor/Instrument/Data Processing Documentation Located at the Soils Lab at the Department of Natural Resources Science at the University of Maryland, College Park, MD 20742: C-H-N-600 Elemental Analyzer System 785-500 Manual. LECO Corp., St. Joseph, MI. Located at BARC: Perkin-Elmer Lambda 3 Double Beam Spectrophotometer Manual. 1988. Perkin-Elmer Corp.. 761 Main Avenue, Norwalk, CT 06859. For 1994: LI-3100 LI-COR Area Meter Manual. Publication number 8805-0055, June 1988 LI- COR, Inc., 4421 Superior Street, P.O. Box 4425, Lincoln, NE 68504-0425. For 1996: LI-3000A LI COR Portable Area Meter Manual., Publication number 8805-0055, June 1988. LI-COR, Inc., 4421 Superior Street, P.O. Box 4425, Lincoln, NE, 68504- 0425. 17.2 Journal Article and Study Reports Anderson, C.P., S.B. McLaughlin, and W.K. Roy. 1991. Foliar injury symptoms and pigment concentrations in red spruce saplings in the southern Appalachians. Can. J. For. Res. v21 n7: 1106-1110. Chappelle, E.W. and M.S. Kim. 1992. Ratio analysis of reflectance spectra (RARS): an algorithm for the remote estimation of the concentration of chlorophyll a, chlorophyll b, and carotenoids in soybean leaves. Remote Sens. Environ. V39: 239-247. Kharouk, V.I., E.M. Middleton, S.L, Spensor, B.N. Rock, and D.L. Williams. 1995. Aspen bark photosynthesis and its significance to remote sensing and carbon budget estimates in the boreal ecosystem. Water, Air and Soil Pollution. V82: 483-497. Lichtenthaler, H.K. 1987. Chlorophylla and carotenoids: pigments of photosynthetic biomembranes. Methods in Enzymology, v148: 350-382. Middleton, E.M., E.W. Chappelle, and A.DeLuca. 1995. Evaluating photosynthesis in Boreal forest species with fluorescence measurements. IGARSS 1995. Middleton, E.M., J.H. Sullivan, B.D. Bovard, A.J. DeLuca, S.S.Chan, and T.A. Cannon. 1997. Seasonal variability in foliar characteristics and physiology for Boreal forest species at the five Saskatchewan tower sites during the 1994 Boreal Ecosystem-Atmosphere Study (BOREAS). J. Geophys. Res. 102 (D24): 28, 831-844. Schneckenburger, H. and W. Schmidt. 1995. Time-resolved chlorophyll fluorescence of spruce needles after different light exposure. Plant Physiol. V148: 593-598. Sellers, P. and F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1994-3.0, NASA BOREAS REPORT (EXPLAN 94). Sellers, P. and F. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1996-2.0, NASA BOREAS REPORT (EXPLAN 96). Sellers, P., F. Hall, and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994 Operations. NASA BOREAS REPORT (OPS DOC 94). Sellers, P., F. Hall, and K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere Study: 1996 Operations. NASA BOREAS REPORT (OPS DOC 96). Sellers, P., F. 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. Boreal Ecosystem-Atmosphere Study (BOREAS): an overview and early results from the 1994 field year. Bulletin of the American Meteorological Society. V76: 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, and F.E. Guertin. 1997. BOREAS in 1997: Experiment Overview, Scientific Results and Future Directions. Journal of Geophysical Research 102 (D24): 28,731-28,770. Sullivan, J.H., B.D. Bovard, and E. M. Middleton, 1996. Variability in leaf- level CO2 and water fluxes in Pinus banksiana and Picea mariana in Saskatchewan. Tree Physiol. V17: 553-561. 17.3 Archive/DBMS Usage Documentation None. 18. Glossary of Terms A nm - Absorptance at a Specified Wavelength (nm) C - Carbon carot - Carotenoid chla - Chlorophyll A chlb - Chlorophyll B C-H-N - Carbon-Hydrogen-Nitrogen DMSO - Dimethyl sulfoxide H - Hydrogen N - Nitrogen 19. List of Acronyms ASCII - American Standard Code for Information Interchange BARC - Beltsville Agricultural Research Center BOREAS - BOReal Ecosystem-Atmosphere Study BORIS - BOREAS Information System DAAC - Distributed Active Archive Center DMSO - Dimethyl Sulfoxide EOS - Earth Observing System EOSDIS - EOS Data and Information System GSFC - Goddard Space Flight Center IFC - Intensive Field Campaign NAD83 - North American Datum of 1983 NASA - National Aeronautics and Space Administration NOAA - National Oceanic and Atmospheric Administration NSA - Northern Study Area OA-AUX - Old Aspen-Auxiliary ORNL - Oak Ridge National Laboratory PANP - Prince Albert National Park SSA - Southern Study Area SSA-OA - SSA Old Aspen SSA-OBS - SSA Old Black Spruce SSA-OJP - SSA Old Jack Pine SSA-YJP - Young Jack Pine TE - Terrestial Ecology URL - Uniform Resource Locator USDA - United States Department of Agriculture UTM - Universal Transverse Mercator WS - White Spruce YA - Young Aspen YA-AUX - Young Aspen-Auxiliary 20. Document Information 20.1 Revision Date Written: 01-OCT-1997. Last updated: 08-OCT-1998. 20.2 Document Review Date(s) BORIS Review: 08-JUL-1998 Science Review: 03-AUG-1998 20.3 Document ID 20.4 Citation Middleton, E.M., of the Biospheric Sciences Branch, GSFC, NASA, and Sullivan, J. H., of the Department of Natural Resource Sciences and Landscape Architecture, University of Maryland, College Park. 20.5 Document Curator 20.6 Document URL Keywords Chlorophyll Pigments Carbon-Hydrogen-Nitrogen Carotenoid TE10_Leaf_Chem.doc 10/09/98