BOREAS TF-01 SSA-OA Soil Characteristics Data Summary The BOREAS TF-01 team collected several data sets in support of its efforts to characterize and interpret soil information at the SSA-OA tower site in 1994 as part of BOREAS. Data sets collected include soil respiration, temperature, moisture, and gravimetric data. The data are stored in tabular ASCII format. 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 TF-01 SSA-OA Soil Characteristics Data 1.2 Data Set Introduction Tower Flux (TF)-01 collected measurements of soil respiration, temperature, moisture, and gravimetric data in an effort to characterize the soil at the Southern Study Area (SSA) Old Aspen (OA) tower site in 1994 as part of the BOReal Ecosystem-Atmosphere Study (BOREAS). 1.3 Objective/Purpose The objectives of this research were to: 1) Determine the efflux of CO2 from the soil using the closed-chamber method and to investigate the flow of C and N through the litter/soil system (Paul Voroney and Craig Russell, University of Guelph). 2) Determine the course of soil moisture content during the year using gravimetric (University of British Columbia) and Time Domain Reflectometry (TDR) (University of Guelph and University of British Columbia). 1.4 Summary of Parameters The soil respiration flux data contain measurements of mean daytime soil CO2 flux, mean daytime soil temperature, mean daytime chamber air temperature, and mean daytime chamber relative humidity. The CO2 concentration data include measurements of the CO2 concentration in the humus soil layer at 62 mm below the surface of the soil and in the surface mineral soil layer at 15 cm below the soil surface. The soil temperature data contain measurements of the mean daily soil temperature at depths of 50 mm, 100 mm, 200 mm, 500 mm, and 1 m. The soil gravimetric data contain measurements of mean gravimetric and mean volumetric soil moisture and mean bulk density taken at the following soil depths: Litter-Fibric-Humus (LFH) organic soil horizons, 0-3 cm, 3-6 cm and 6-10 cm, and 0-15 cm and 15-30 cm. The soil moisture data contain measurements of soil moisture in the mid-humus, mineral soil, and submineral soil layers taken at locations A, B, C, and D at the SSA-OA site using surface probes. Soil moisture was also measured at depths ranging from 0 cm to 120 cm in increments of 15 cm using depth probes read by Tektronix Cable Tester and Moisture Point (Gabel Corp.) instruments. The soil moisture summary data contain means, variation coefficients, and the number of observations of the soil moisture data as discussed above. 1.5 Discussion TF-01 collected measurements of soil respiration, temperature, moisture, and gravimetric data in an effort to characterize the soil at the SSA-OA tower site in 1994 as part of BOREAS. The closed chamber was the primary method of measuring soil CO2 efflux. The data from this method were used to obtain the seasonal pattern of soil CO2 efflux. The open chamber method was used over a 3- week period late in the growing season to determine the diurnal patterns of soil CO2 efflux. A soil temperature profile was taken at depths of 2, 5, 10, 20, 50, and 100 cm using CSI direct-burial copper-constantan thermocouples. Gravimetric measurements of soil water content of the surface layers (0-3, 3-6, and 6-10 cm) were made every 2-3 days. In addition, the TDR technique (Hook and Livingston, 1996) was also used. Two probes consisting of three stainless steel roads (3 mm in diameter, 30 cm long, and 2 cm apart) were positioned horizontally at 8-cm (organic layer) and 15-cm (mineral layer) depths. Five 120- cm segmented rods (two thin stainless steel strips 1.2 cm wide and 1.5 cm apart bonded by an epoxy resin layer) were installed to measure average water content in 15-cm (0- to 30-cm depth) and 30-cm layers (30- to 120-cm depth). The TDR rods near hut B (University of British Columbia) were mainly read using the Tektronix Cable Tester in hut B with signal cables (about 30 m long) extending out to the TDR rods. A small manually weighed lysimeter (15 cm diameter x 15 cm deep) was operated for 15 days in July and August of 1994 to determine the magnitude of evaporation from the soil. 1.6 Related Data Sets BOREAS HYD-06 Moss/Humus Moisture Data BOREAS TE-01 Soils Data over the SSA Tower Sites in Raster Format BOREAS TF-01 SSA-OA Tower Flux, Meteorological, and Soil Temperature Data BOREAS TF-01 SSA-OA Understory Flux, Meteorological, and Soil Temperature Data BOREAS TF-02 SSA-OA Tower Flux, Meteorological, and Precipitation Data BOREAS TGB-01 Soil CH4 And CO2 Profile Data From NSA Tower Sites BOREAS TGB-12 Soil Carbon Data over the NSA 2. Investigator(s) 2.1 Investigator(s) Name and Title Dr. T. Andy Black, Professor 2.2 Title of Investigation Boreal Forest Atmosphere Interactions: Exchanges of Energy, Water Vapor and Trace Gases (SSA-OA) 2.3 Contact Information Contact 1: Mr. Zoran Nesic University of British Columbia Department of Soil Science Vancouver, BC CANADA (604) 822-3479 (604) 822-5654 (Lab) (604) 822-8639 (fax) NESIC@PPC.UBC.CA Contact 2: Prof. T. Andy Black University of British Columbia Department of Soil Science Vancouver, BC CANADA (604) 822-2730 (604) 822-8639 (fax) ablack@unixg.ubc.ca Contact 3: Andrea Papagno Raytheon ITSS NASA GSFC Greenbelt, MD (301) 286-3134 (301) 286-0239 (fax) Andrea.Papagno@gsfc.nasa.gov 3. Theory of Measurements Three methods were employed to estimate soil CO2 efflux. The first method used Fick's law, which required estimates of soil gas (CO2) diffusivity and measured CO2 concentration gradients. See Section 18 for a definition of Fick's law. The second method used the accumulation of gas within a chamber placed over the soil surface (static closed chamber). The third method is the steady-state or dynamic open chamber. In this method, flow rate through the chamber and the difference in gas concentration between the inlet and outlet of the chamber are measured. The CO2 efflux is given by the product of the concentration difference and flow rate. These estimates were compared with nighttime eddy covariance CO2 fluxes (Russell et al., 1998). TDR relies on the different dielectric constants for water and air to detect the reflection of a high-frequency electromagnetic pulse sent down a transmission line or wave guide, with volume water content related to the apparent dielectric constant by a model described by Hook and Livingston (1996). 4. Equipment 4.1 Sensor/Instrument Description 4.1.1 Collection Environment Soil respiration, soil CO2 concentrations, gravimetric, and soil moisture data were collected by TF-01 from the ground or from the soil respiration boardwalk at the SSA-OA site. Soil respiration was measured with a LI-COR 6200 portable photosynthesis unit from the 6000-09 soil respiration chamber. Data are daytime averages of daily observations recorded between 10 a.m. and 4 p.m. local time. Soil CO2 concentrations were collected in evacuated containers from sampling lines in the surface soil. Data are daily averages of half-hour observations. Data for 0.05, 0.1, and 0.2 m below the soil surface are averages of three probes (one close to tower, i.e., University of British Columbia probes, and two along soil respiration boardwalk, i.e., University of Guelph probes). Data for 0.5 and 1.0 m were recorded from one set of probes close to the SSA-OA flux tower. Gravimetric data were derived from the weight loss of wet soil after 72 hours in an oven at 60 _C for organic soil samples and at 105 _C for mineral soil samples. Soil moisture was determined from the time delay along probe transmission lines, i.e., TDR. Time delays were converted to volumetric moisture contents using the Hook and Livingston (1992) equation where the ratio of the time delay in dry soil to that in air was 1.2 for organic soil and 1.55 for mineral soil. Two types of TDR probes were used. Surface probes consisted of three parallel 0.3-m lengths of stainless steel welding rod 2 cm apart. These were inserted into surface soil layers, i.e., 0 to 0.3 m in a horizontal orientation, and connected to a Tektronix cable tester via lengths of coaxial cable. Depth probes were purchased from Environmental Sensors, Inc., along with a MoisturePoint TDR analysis instrument. The depth probes could be read by both Tektronix and MoisturePoint instruments. The depth probes were 4 feet in length and could estimate soil moisture content along five segments (6", 6", 1', 1', 1'). These probes were inserted vertically into the forest floor. 4.1.2 Source/Platform Soil respiration, soil CO2 concentrations, gravimetric, and soil moisture data were collected by TF-01 from the ground or from the soil respiration boardwalk at the SSA-OA site. 4.1.3 Source/Platform Mission Objectives The general objective was to study carbon dioxide and water vapor exchange between the forest and atmosphere at SSA-OA. Specific objectives were to: ? Measure the fluxes of sensible heat, H2O, and CO2 above the aspen stand throughout the year. ? Obtain from the CO2 flux data estimates of gross photosynthesis and respiration. ? Determine the contribution of the hazelnut understory to net ecosystem productivity (NEP). ? Determine the effects of environmental factors on stand evapotranspiration (E) and NEP. ? Take part in the development of procedures for scaling up component fluxes to the stand level. ? Study the processes controlling turbulent transfer of H2O and CO2 within the stand. ? Take part in the evaluation of methods of estimating nocturnal CO2 in and above the stand. 4.1.4 Key Variables Mean soil CO2 flux, soil CO2 concentration, mean volumetric soil moisture, mean soil temperature, mean soil bulk density, mean gravimetric soil moisture, mean TDR soil moisture, and TDR soil moisture. 4.1.5 Principles of Operation The principles of operation of most of the instruments can be found in Pearcy et al., 1991, and Fritschen and Gay, 1979. (See Sections 3 and 4.1.1 also.) 4.1.6 Sensor/Instrument Measurement Geometry Closed chamber: Inner diameter 9.55 cm and height 14.60 cm. Open chamber: Collar inner diameter 20 cm and collar height 10 cm (Russell et al., 1998). TDR: 120-cm segmented (two 15-cm segments and three 30-cm segments) rods (two stainless steel strips 2 cm apart separated by epoxy) with shorting diodes (Hook et al., 1992). 4.1.7 Manufacturer of Sensor/Instrument Cable Length Tester (model 1502B & C) Tektronix, Inc 26600 SW Parkway Wilsonville, OR 97070 800-TEK-WIDE Data logging system 21x, CR10 Campbell Scientific P.O. Box 551, Logan, UT 84321 USA (801) 753-2342 (801) 752-3268 (fax) Field (110 VAC) drying oven LI-COR 6200 portable photosynthesis unit and 6000-09 soil respiration chamber LI-COR, Inc. P.O. Box 4425/4421 Superior Street Lincoln, NE 68504 (303) 499-1701 (303) 499-1767 (fax) Soil temperature (burial) Campbell Thermocouple Copper-constantan thermocouple Campbell Scientific P.O. Box 551, Logan, UT 84321 USA (801) 753-2342 (801) 752-3268 (fax) Thermal conductivity gas chromatography instrumentation (University of Guelph) Datalogger model 21X Campbell Scientific, Inc. (CSI) P.O. Box 551 Logan, UT 84321 (801) 753-234 (801) 752-3268 (fax) TDR TDR depth (segmented) probes and Moisture Point Depth Probe Reader G.S. Gabel & Associates Ltd. 100 - 4243 Glanford Avenue Victoria, British Columbia, Canada V8Z 4B9 (250) 479-6588 (general) (800) 799-6324 (within North America only) (250) 479-1412 (fax) info@esica.com http://www.esica.com/ TDR surface probes (three stainless steel rods and two diodes) (homemade) 4.2 Calibration 4.2.1 Specifications The TDR calibration was done in the field using gravimetric sampling and a bulk density profile. Chamber calibration was done by using calibration gases used to calibrate the eddy correlation/CO2 profile analyzers. Analysis was performed at the Atmospheric Environment Service (AES) Headquarters, Downsview, Ontario, Canada, using a standard traceable to a Scripps analysis in 1993. 4.2.1.1 Tolerance None given. 4.2.2 Frequency of Calibration Soil chamber: Infrared Gas Analyzer (IRGA): three times during 1994 growing season. TDR: Organic surface layer: calibrated using gravimetric samples taken every 2-3 days in 1994 (Blanken et al., 1997). TDR: Mineral layers: calibrated using gravimetric profiles (two) in 1994. 4.2.3 Other Calibration Information Not applicable. 5. Data Acquisition Methods Soil respiration (CO2 efflux) was measured with a LI-COR 6200 portable photosynthesis unit from the 6000-09 soil respiration chamber. This unit also facilitates measurements of chamber temperature, relative humidity, and soil temperature adjacent to the chamber. Data are daytime averages of daily observations recorded between 10 a.m. and 4 p.m. SSA local time. Soil CO2 concentrations were collected in evacuated containers from sampling lines in the surface soil. These samples were analyzed for CO2 concentration by thermal conductivity gas chromatography. Soil temperatures were measured with thermocouples attached to a Campbell 21X datalogger. Data are daily averages of half-hour observations. Data for 0.05, 0.1, and 0.2 m are averages of three probes (one close to tower, i.e., University of British Columbia probes, and two along soil respiration boardwalk, i.e., University of Guelph probes). Data for 0.5 and 1.0 m were recorded from one set of probes close to the tower. Gravimetric data were derived from the weight loss of wet soil after 72 hours in an oven at 60 _C for organic soil samples and at 105 _C for mineral soil samples. Soil moisture was determined from the time delay along probe transmission lines, i.e., TDR. Time delays were converted to volumetric moisture contents using the Hook and Livingston (1992) equation where the ratio of the time delay in dry soil to that in air was 1.2 for organic soil and 1.55 for mineral soil. Two types of TDR probes were used, surface and depth. Surface probes consisted of three parallel 0.3-m lengths of stainless steel welding rod 2 cm apart. These were inserted into surface soil layers, i.e., 0 to 0.3 m in a horizontal orientation, and connected to a Tektronix cable tester via lengths of coaxial cable. TDR depth probes and Moisture Point electronics were purchased from Gabel Corp. The depth probes could also be read by the Tektronix cable tester. The depth probes were 4 feet in length and could estimate soil moisture content along five segments (6 inches, 6 inches, 1 foot, 1 foot, 1 foot). These probes were inserted vertically into the forest floor. Extensive details of methods and equipment is outlined in the publications (i.e., Russell and Voroney, 1998; Russell et al., 1998; Black et al., 1996; Chen et al., 1999). For the main flux system, all raw data were recorded using PC computer systems with backup tape drives. Half-hour fluxes were calculated online. For other measurements, all those data were recorded by data loggers (model 21X, Campbell Scientific, Inc., Logan, UT), which were networked together (using the model MD- 9 network interface ) along with the main system. Every 3 hours, this network automatically transferred (using pc ANYWHERE, Symantec Corp.) all data from the loggers to a network computer. This computer was accessed from our laboratory at University of British Columbia through a communication system, which comprised a modem, cellular phone, and Yagi antenna at the site, and a phone and modem in the laboratory. The Yagi antenna was mounted above the trees and the cellular phone was housed in a thermostatically controlled box near the antenna. At midnight the site computer compressed the previous 24 hours of half-hour flux data, called the laboratory, and in 3 minutes transferred (using Kermit) the compressed data to the laboratory computer. 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 The SSA measurement site and associated North American Datum of 1983 (NAD83) coordinates are: SSA-OA, site id C3B7T, Lat/Long: 53.62889° N, 106.19779° W, UTM Zone 13, N: 5942899.9, E: 420790.5. 7.1.2 Spatial Coverage Map Not available. 7.1.3 Spatial Resolution The data are point measurements at the given location. 7.1.4 Projection Not applicable. 7.1.5 Grid Description Not applicable. 7.2 Temporal Characteristics 7.2.1 Temporal Coverage Measurement occurred between 10 a.m. and 4 p.m. SSA local time. 7.2.2 Temporal Coverage Map None given. 7.2.3 Temporal Resolution None given. 7.3 Data Characteristics Data characteristics are defined in the companion data definition file (tf01soil.def). 7.4 Sample Data Record Sample data format shown in the companion data definition file (tf01soil.def). 8. Data Organization 8.1 Data Granularity The TF-01 SSA-OA Soil Characteristics Data are contained six data files: soil CO2 concentrations; gravimetric soil moisture; summarized soil moisture; volumetric soil moisture; soil respiration; and soil temperature. 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 single apostrophe marks. There are no spaces between the fields. Sample data records are shown in the companion data definition file (tf01soil.def). 9. Data Manipulations 9.1 Formulae 9.1.1 Derivation Techniques and Algorithms None given. 9.2 Data Processing Sequence None given. 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 None given. 10.2 Quality Assessment None given. 10.2.1 Data Validation by Source Data have been reviewed by TF-01 personnel. 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 The data were 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 This data set can be used to study the soil properties of an aspen boreal forest. 13. Future Modifications and Plans None given. 14. Software 14.1 Software Description None given. 14.2 Software Access None given. 15. Data Access 15.1 Contact for Data Center/Data Access Information These BOREAS data are available from the Earth Observing System Data and Information System (EOS-DIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The BOREAS contact at ORNL is: ORNL DAAC User Services Oak Ridge National Laboratory (865) 241-3952 ornldaac@ornl.gov ornl@eos.nasa.gov 15.2 Procedures for Obtaining Data BOREAS data may be obtained through the ORNL DAAC World Wide Web site at http://www-eosdis.ornl.gov/ or users may place requests for data by telephone, electronic mail, or fax. 15.3 Output Products and Availability Requested data can be provided electronically on the ORNL DAAC's anonymous FTP site or on various media including, CD-ROMs, 8-MM tapes, or diskettes. The complete set of BOREAS data CD-ROMs, entitled "Collected Data of the Boreal Ecosystem-Atmosphere Study", edited by Newcomer, J., et al., NASA, 1999, are also available. 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 given. 17.2 Journal Articles and Study Reports Black, T.A, G. den Hartog, H.H. Neumann, P.D. Blanken, P.C. Yang, C. Russell, Z. Nesic, X. Lee, S.G. Chen, R. Staebler, and M.D. Novak. 1996. Annual cycles of water vapour and carbon dioxide fluxes in and above a boreal aspen forest. Global Change Biology 2: 219-229. Blanken, P.D., T.A. Black, P.C. Yang, H.H. Neumann, Z. Nesic, R. Staebler, G. den Hartog, M.D. Novak, and X. Lee. 1997. Energy balance and canopy conductance of a boreal aspen forest: Partitioning overstory and understory components. Journal of Geophysical Research 102: 28,915-28,927. Chen, W.J., T.A. Black, P.C. Yang, A.G. Barr, H.H. Neumann, Z. Nesic, P.D. Blanken, M.D. Novak, J. Eley, R.J. Ketler, and R. Cuenca. 1999. Effects of climatic variability on the annual carbon sequestration by a boreal aspen forest. Global Change Biology 5: 41-53. Fritschen, L.J. and L.W. Gay. 1979. Environmental Instrumentation. Springer- Verlag, Berlin, New York and Heidelberg. Hook, W.R. and N.J. Livingston. 1996. Errors in converting time domain reflectometry measurements of propagation velocity to estimates of soil water content. Soil Science Society of America Journal. 60: 35-41. Hook, W.R., N.J. Livingston, Z.J. Sun, and P.B. Hook. 1992. Remote diode shorting improves measurement of soil water by time domain reflectometry. Soil Science Society of America Journal 56: 1384-1391. 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. Pearcy, R.W., J Ehleringer, H.A. Mooney, and P.W. Rundel. 1991. Plant physiological ecology: Field methods and instrumentation. Chapman and Hall, London and New York. Russell, C.A. and R.P. Voroney. 1998. Carbon dioxide efflux from the floor of a boreal aspen forest. I. Relationship to environmental variables and estimates of C respired. Can. J. Soil Sci. 78:301-310. Russell, C.A., R.P. Voroney, T.A. Black, P.D. Blanken, and P.C. Yang. 1998. Carbon dioxide efflux from the floor of a boreal aspen forest. II. Evaluation of methods - verification by infra-red analysis of a dynamic closed chamber. Can. J. Soil Sci. 78:311-316. 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. 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.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. Soil Classification Working Group (Eds.). 1998. The Canadian System of Soil Classification. 3rd Edition. Agriculture and Agri-Food Canada Publication 1646. National Resource Council of Canada Research Press. Ottawa, Ontario, Canada. 187 pp. 17.3 Archive/DBMS Usage Documentation None. 18. Glossary of Terms E - Evapotranspiration. F - Fibric: this is an organic horizon characterized by an accumulation of partly decomposed organic matter. The original structures in part are difficult to recognize. The horizon may be partly comminuted by soil fauna as in moder, or it may be a partly decomposed mat permeated by fungal hyphae as in mor. Fick's Law - This law states that the rate of diffusion, M, of one material through another is proportional to the cross sectional area of diffusion, A, the concentration gradient, dC/dX, and the diffusion coefficient, D. Their relationship is M = -D*A*(dC/dX). H - Humus: this is an organic horizon characterized by an accumulation of decomposed organic matter in which the original structures are indiscernible. This material differs from the F horizon by its greater humification chiefly through the action of organisms. It is frequently intermixed with mineral grains, especially near the junction with the mineral horizon. L - Litter: this is an organic horizon characterized by an accumulation of organic matter in which the original structures are easily discernible. LFH - The major organic horizons are L, F, and H, which consist mainly of forest litter at various stages of decomposition. These organic horizons developed primarily from leaves, twigs, woody materials, and a minor component of mosses under imperfectly to well-drained forest conditions. 19. List of Acronyms AES - Atmospheric Environmental Service ASCII - American Standard Code for Information Interchange Batoche - The study site located in the Batoche National Historic Park BFTCS - Boreal Forest Transect Case Study BOREAS - BOReal Ecosystem-Atmosphere Study BORIS - BOREAS Information System CD-ROM - Compact Disk-Read-Only Memory CFS - Canadian Forest Service DAAC - Distributed Active Archive Center DOY - Julian Day of Year EOS - Earth Observing System EOSDIS - EOS Data and Information System GIS - Geographic Information System GMT - Greenwich Mean Time GSFC - Goddard Space Flight Center HTML - HyperText Markup Language IFC - Intensive Field Campaign IRGA - Infrared Gas Analyzer NAD83 - North American Datum of 1983 NASA - National Aeronautics and Space Administration NEP - Net Ecosystem Productivity NOAA - National Oceanic and Atmospheric Administration NSA - Northern Study Area OA - Old Aspen ORNL - Oak Ridge National Laboratory PANP - Prince Albert National Park RSS - Remote Sensing Science S - Sap Flux Density SSA - Southern Study Area TDR - Time Domain Reflectometry TE - Terrestrial Ecology TF - Tower Flux URL - Uniform Resource Locator UTM - Universal Transverse Mercator 20. Document Information 20.1 Document Revision Date Written: 09-Jul-1999 Last Updated: 29-Sep-1999 20.2 Document Review Date(s) BORIS Review: 21-Jul-1999 Science Review: 20.3 Document ID 20.4 Citation When using these data, please acknowledge T. Andy Black and Z. Nesic of the University of British Columbia, and include citations of relevant papers in Section 17.2. If using data from the BOREAS CD-ROM series, also reference the data as: Black, T.A., "Boreal Forest Atmosphere Interactions: Exchanges of Energy, Water Vapor and Trace Gases (SSA-OA)." 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 Keywords: CO2 Concentration CO2 Flux Gravimetric Data Soil Moisture Soil Respiration Soil Temperature Time Domain Reflectometry TF01_Soils.doc 09/30/99