BOREAS TE-05 Leaf Gas Exchange Data Summary The BOREAS TE-05 team collected measurements in the NSA and SSA on gas exchange, gas composition and tree growth. The leaf photosynthetic gas exchange data were collected in the BOREAS NSA and the SSA using a Li-Cor 6200 portable photosynthesis system. The data were collected to compare the photosynthetic capacity, stomatal conductance and leaf intercellular CO2 concentrations among the major tree species at the BOREAS sites. The data are average values from diurnal measurements on the upper canopy foliage (sun leaves). The data are available 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 Leaf photosynthetic gas exchange data collected in the field using a Li-Cor 6200 portable photosynthesis system. 1.1 Data Set Identification BOREAS TE-05 Leaf Gas Exchange data 1.2 Data Set Introduction Leaf photosynthetic gas exchange data were collected in the field using a Li-Cor 6200 portable photosynthesis system. The data are average values from diurnal measurements on the upper canopy foliage (sun leaves). 1.3 Objective/Purpose The data were collected to compare the photosynthetic capacity, stomatal conductance and leaf intercellular CO2 concentrations among the major tree species at the BOREAS sites. The leaf intercellular CO2 concentrations obtained from our gas exchange studies were also compared to calculated values based on our measurements of leaf carbon isotope ratios. 1.4 Summary of Parameters CO2 flux, Chamber CO2 concentration Chamber CO2 pressure, Intercellular CO2 pressure, Leaf surface area, Leaf water potential 1.5 Discussion These measurements were collected in 1994 at the southern study area (SSA) during each Intensive Field Campaign (IFC) at Old Jack Pine (OJP) and Old Black Spruce (OBS) sites. Measurements were also made at the Old Aspen (OA) site during IFC2 (summer). Measurements were collected in 1994 at the northern study area (NSA) during IFC1 and IFC2 at the old Jack Pine, T6R5S TE Upland Black Spruce (UBS), and T2Q6A TE Old Aspen. 1.6 Related Data Sets BOREAS TE-05 CO2 Concentration and Stable Isotope Composition BOREAS TE-05 Diurnal CO2 Canopy Profile Data BOREAS TE-05 Soil Respiration Data BOREAS TE-05 Leaf Carbon Isotope Data BOREAS TE-05 Surface Meteorological and Radiation Data BOREAS TE-05 Tree Ring and Carbon Isotope Ratio Data 2. Investigator(s) 2.1 Investigator(s) Name and Title J.R. Ehleringer, University of Utah, TE-05 Department of Biology Salt Lake City, UT Dr. Larry Flanagan Department of Biological Sciences University of Lethbridge 2.2 Title of Investigation Vegetation-Atmosphere CO2 and H2O Exchange Processes: Stable Isotope Analyses 2.3 Contact Information Contact 1 --------- J. Renee Brooks Department of Biology University of South Florida Tampa, Florida (813) 974-7352 (813) 974-3263 (fax) jrbrooks@chuma.cas.usf.edu Contact 2 --------- Dr. Larry Flanagan Department of Biological Sciences University of Lethbridge Lethbridge, Alberta CANADA (403) 380-1858 (403) 329-2082 (fax) larry.flanagan@uleth.ca Contact 3 --------- 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 Measurements were made using a Li-Cor 6200 portable photosynthesis system, an instrument that uses a closed loop technique. This is a standard instrument for field measurements of leaf photosynthesis gas exchange. Theoretical details of the measurements and instruments can be obtained Li-Cor Inc. P.O. Box 4425 Superior Street, Lincoln, Nebraska, 68504, USA. 4. Equipment 4.1 Sensor/Instrument Description Measurements were made using a Li-Cor 6200 portable photosynthesis system, an instrument that uses a closed loop technique. This is a standard instrument for field measurements of leaf photosynthesis gas exchange. 4.1.1 Collection Environment Environmental conditions on sampling day should be included in the BOREAS TE-05 Meteorological data. 4.1.2 Source/Platform Li-Cor 6200 Portable photosynthesis system. 4.1.3 Source/Platform Mission Objectives The data were collected to compare the photosynthetic capacity, stomatal conductance and leaf intercellular CO2 concentrations among the major tree species at the BOREAS sites. 4.1.4 Key Variables CO2 Flux Stomatal Conductance Intercellular CO2 concentration Vapor Pressure Photosynthetic Photon Flux Density (PPFD) 4.1.5 Principles of Operation None given. 4.1.6 Sensor/Instrument Measurement Geometry None given. 4.1.7 Manufacture of Sensor/Instrument Li-Cor Inc. P.O. Box 4425 Superior Street, Lincoln, Nebraska, 68504, USA. Toll free telephone 1-800-447-3576 (US and Canada), telephone (402) 467-2819. 4.2 Calibration The infrared gas analyzer of the Li-Cor 6200 portable photosynthesis system was calibrated using primary standard gas mixtures from Matheson Gas. These gas mixtures were compared to BOREAS project calibration standards. The humidity sensor was calibrated using a Li-Cor dew point generator. Other components of the Li-Cor 6200 (e.g. flow meters) were calibrated at the Li-Cor factory before the field season began. 5. Data Acquisition Methods None given. 6. Observations 6.1. Data Notes None given. 6.2 Field Notes None given. 7. Data Description 7.1 Spatial Characteristics 7.1.1 Spatial Coverage Samples were collected at NSA OJP, SSA OJP, SSA OBS, and NSA UBS in 1993 and all the sites listed below in 1994: NSA OJP flux tower site: Lat/Long=55.927 N, 98.62 W, Universal Transverse Mercator (UTM) Zone 14, N:6,197,997 E:523,501. SSA OJP flux tower site: Lat/Long=53.916 N, 104.69 W, UTM Zone 13, N:5,951,000 E:479,400. NSA OA canopy access tower site (auxiliary site number T2Q6A, BOREAS Experiment Plan, Version 3). Lat/Long = 55.88N, 98.67 W SSA OA flux tower site: Lat/Long=53.629 N, 106.197 W, UTM Zone 13, N:5,942,688 E:420,874. NSA UBS canopy access tower site (auxiliary site number T6R5S, BOREAS Experiment Plan, Version 3). Lat/Long = 55.70N, 98.51W SSA OBS flux tower site: Lat/Long = 53.985 N, 105.122 W, UTM Zone 13, N:5,981,904 E:492,000. 7.1.2 Spatial Coverage Map Not applicable. 7.1.3 Spatial Resolution These 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 These measurements were collected from 06-JUN-94 to 13-SEP-94. 7.2.2 Temporal Coverage Map Not avaliable. 7.2.3 Temporal Resolution The data are average values from diurnal measurements on the upper canopy foliage (sun leaves). These measurements were collected at the SSA during each 1994 IFC at OJP and OBS. Measurements were also made at the old Aspen site during IFC2 (summer 1994). Measurements were collected at the NSA during 1994 IFC1 and IFC2 at the OJP, UBS, and OA. 7.3 Data Characteristics Data characteristics are defined in the companion data definition file (te5lgxd.def). 7.4 Sample Data Record Sample data format shown in the companion data definition file (te5lgxd.def). 8. Data Organization 8.1 Data Granularity All of the Leaf Gas Exchange Data are contained in one dataset. 8.2 Data Format The data file contains 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 (te5lgxd.def). 9. Data Manipulations 9.1 Formulae 9.1.1 Derivation Techniques and Algorithms None given. 9.2 Data Processing Sequence 9.2.1 Processing Steps None given. 9.2.2 Processing Changes None given. 9.3 Calculations 9.3.1 Special Corrections/Adjustments None given. 9.3.2 Calculated Variables None given. 9.4 Graphs and Plots None given. 10. Errors 10.1 Sources of Error All known errors have been removed from the data. 10.2 Quality Assessment None given. 10.2.1 Data Validation by Source None given. 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 Data was examined for general consistency and clarity. 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 None. 14.2 Software Access None. 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-05 leaf gas exchange 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 contract at ORNL is: ORNL DAAC User Services Oak Ridge National Laboratory (865) 241-3952 ornldaac@ornl.gov ornl@eos.nasa.gov 16. Output Products 16.1 Tape Products None. 16.2 Film Products None. 16.3 Other Products The data are available in tabular ASCII files. 17. References 17.1 Platform/Sensor/Instrument/Data Processing Documentation None. 17.2 Journal Articles Brooks, J.R., L.B. Flanagan, G.T. Varney, and J.R. Ehleringer. 1997. Vertical gradients in photosynthetic gas exchange characteristics and refixation of respired CO2 within boreal forest canopies. Tree Physiology 17: 1-12. Sellers, P. and F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1994-3.0, NASA BOREAS Report (EXPLAN 94). 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. The boreal ecosystem-atmosphere study (BOREAS): an overview and early results from the 1994 field year. Bulletin of the American Meteorological Society. 76(9):1549-1577. Sellers, P., F. Hall, and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994 Operations. NASA BOREAS Report (OPS DOC 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. 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 102 (D24): 28,731-28,770. 17.3 Archive/DBMS Usage Documentation 18. Glossary of Terms None given. 19. List of Acronyms ASCII - American Standard Code for Information Interchange BOREAS - BOReal Ecosystem-Atmosphere Study BORIS - BOREAS Information System DAAC - Distributed Active Archive Center EOS - Earth Observing System EOSDIS - EOS Data and Information System GSFC - Goddard Space Flight Center HSA - Hemi-surface area NASA - National Aeronautics and Space Administration NSA - Northern Study Area OA - Old Aspen OBS - Old Black Spruce OJP - Old Jack Pine ORNL - Oak Ridge National Laboratory PANP - Prince Albert National Park SSA - Southern Study Area TE - Terrestrial Ecology TLA - Total Leaf Area UBS - Upland Black Spruce URL - Uniform Resource Locator UTM - Universal Transverse Mercator 20. Document Information 20.1 Document Revision Date Written : 10-Jun-1997 Last Updated: 28-Sep-1998 20.2 Document Review Date(s) BORIS Review: 02-Jun-1998 Science Review: 20.3 Document 20.4 Citation Please contact Investigators listed in Section 2.3 Contact Information. 20.5 Document Curator 20.6 Document URL Keywords CO2 Flux Surface Area Water Potential TE05_Leaf_Gas_Exch 05/07/99