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biota

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  • Ecosystem simulation models use descriptive input parameters to establish the physiology, biochemistry, structure, and allocation patterns of vegetation functional types, or biomes. For single-stand simulations, it is possible to measure required data, but as spatial resolution increases, data availability decreases. Generalized biome parameterizations are then required. Undocumented parameter selection and unknown model sensitivity to parameter variation for larger-resolution simulations are currently the major limitations to global and regional modeling. We present documented input parameters for process-based ecosystem simulation models (specifically for the BIOME-BGC) for major natural temperate biomes. Parameter groups include the following: turnover and mortality; allocation; carbon to nitrogen ratios (C:N); the percent of plant material in labile, cellulose, and lignin pools; leaf morphology; leaf conductance rates and limitations; canopy water interception and light extinction; and the percent of leaf nitrogen in Rubisco (i.e., ribulose bisphosphate-1,5-carboxylase/oxygenase). Input parameters may also be used for other ecosystem models. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]white_parameters ]

  • Data from the LAI-2000 instrument were processed to determine the leaf area index (LAI) at the EOS Validation Core Site in Kataba Local Forest, approximately 20 km south of Mongu, Zambia. Measurements began in 2000 and continued into 2002, with measurements collected about every month throughout the growing season to examine the phenology of LAI for the site. The LAI-2000 measures the intensity of blue light in five upward-looking concentric conical rings. Measurements are made under the forest canopy and compared with open-sky measurements to determine transmittance for each of the five viewing angles. The sensor head was placed at ground level while the sensors measured light levels in conical scans. Effective leaf area was calculated from the transmittance in the different view angles based on the assumption of a random distribution of leaves (Welles and Norman, 1991).The LAI-2000 was carried along three parallel transects, each 750 m long and spaced 250 m apart. Each transect was divided into 25 m segments, and measurements were collected at the endpoints of each segment. Data from all transects were combined to provide site-average LAI for each sampling date. The length and spacing of the transects were chosen to sample an area large enough to be representative of a 1 km MODIS pixel. Ground observations of LAI from this study compared with MODIS LAI products were found to be in close agreement.The data are stored in an ASCII text file, in comma-separated-value (csv) format, with column headers. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]s2k_lai-2000 ]

  • Field measurements of biomass and associated environmental data were compiled for multiple study sites in major grassland types worldwide. When sufficient biomass data were available, we compared NPP estimated by six different algorithms for 31 grassland sites to examine potential bias associated with the algorithms (Scurlock et al. 2002). This data set includes monthly grassland biomass data and NPP estimates produced by the different algorithms. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]npp_grassland_31 ]

  • The BOREAS TE-02 team collected several data sets in support of its efforts to characterize and interpret information on the respiration of the foliage, roots, and wood of boreal vegetation. This data set contains measurements of growth and sapwood of the stems conducted in the NSA during the growing season of 1994. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE2STSAP ]

  • This data set documentation is currently in work. In the interim, an abstract of the entire Superior National Forest (SNF) data collection activity from which the SNF Vegetation Cover Data: C. Jarvis Data Set is a product is being provided. During the summers of 1983 and 1984, the National Aeronautics and Space Administration (NASA) conducted an intensive experiment in a portion of the Superior National Forest (SNF) near Ely, Minnesota, USA. The purpose of the experiment was to investigate the ability of remote sensing to provide estimates of biophysical properties of ecosystems, such as leaf area index (LAI), biomass and net primary productivity (NPP). The study area covered a 50 x 50 km area centered at approximately 48 degrees North latitude and 92 degrees West longitude in northeastern Minnesota at the southern edge of the North American boreal forest. The SNF is mostly covered by boreal forest. Boreal forests were chosen for this project because of their relative taxonomic simplicity, their great extent, and their potential sensitivity to climatic change. Satellite, aircraft, helicopter and ground observations were obtained for the study area. These data comprise a unique dataset for the investigation of the relationships between the radiometric and biophysical properties of vegetated canopies. This is perhaps the most complete dataset of its type ever collected over a forested region. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]SNF_CJ_VEG ]

  • Klong Hoi Khong Site (Thailand) Net primary production of a humid savanna grassland was determined at the Klong Hoi Khong study site belonging to Prince of Songkla University in southern Thailand. Monthly dynamics of live biomass and dead matter, above and below ground, were monitored from 1984 to the present, together with monthly litter bag estimates of decomposition rates above and below ground. The method for calculating net primary production accounted for simultaneous growth and death, and carbon flows to all trophic levels. Work was carried out under the United Nations Environment Program (UNEP) Project on "Primary Productivity of Grass Ecosystems of the Tropics" and has continued under subsequent UNEP and Thai-Austrian research projects. The study site of several hectares is situated within a larger experimental field area (6.3 N 100.9 E), about 40 km south-west of Hat Yai. Ancient shifting cultivation in the region originally converted the tropical forest to a savanna-like tree-grass mosaic on poorer soils. The study site has supported a humid savanna for at least the last 50-100 years, and is typical of the semi-natural pastures in the Thai/Malaysian Peninsula which were until recently commonly maintained by burning. However, much of the region is now under pressure for conversion to arable crops or rubber plantations. Net primary productivity was determined, initially under the auspices of an international collaborative UNEP Project, since there was a lack of information on the productive capacity and carbon cycling of the region. Complete data are available 1984-1990, including accidental burning in 1986 and 1989. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]NPP_KLN ]

  • Productivity of a meadow steppe was determined at the Kursk long-term ecological study site from 1954 to 1983. Measurement of monthly dynamics of above-ground plant biomass were made for each growing season (April-October), although the data on live and dead matter are more sparse and root data collection covers only some years in the 1970s and 80s. Above-ground net primary production was estimated for many years, but the record is discontinuous. These data are part of a series of grassland data sets recently assembled and checked by Dr. Tagir Gilmanov, which cover a wide range of climate and "continentality" (increasing maximum summer temperatures, decreasing precipitation) from the North-West to the South-East of the Commonwealth of Independent States (former USSR). Climate data for this site are also available: see Any Other Relevant Information in section 11 of this document. More information on the entire Net Primary Production Project can be found at the NPP homepage. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]NPP_KRS ]

  • Productivity of a humid grass savanna was determined at the Lamto Research Station, Cote Ivoire, operated in collaboration with CNRS (Centre Nationale de Recherche Scientifique) - Ecole Normale Superieure, Paris, France. Measurement of monthly dynamics of above-ground plant matter (live biomass and dead matter for some years, total biomass in other years), and total roots (live + dead), were monitored from 1969 to 1987. Net primary production has been estimated for both above and below-ground, although more data is available on the former. Climate data for this site are also available: see Any Other Relevant Information in section 11 of this document. More information on the entire Net Primary Production Project can be found at the NPP homepage. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]NPP_LMT ]

  • The BOREAS TE-07 team collected data sets in support of its efforts to characterize and interpret information on the sapflow and dendrology of boreal vegetation. This data set contains dendrology measurements, consisting of tree ring width and density taken at several points within each ring. Measurements were taken near the TE towers at the OJP and OBS sites in NSA. In the SSA, measurements were taken near the TE towers at the MIX, OBS, and OJP sites; at the AIM-13 and BMH-9 sites; and near the TF-YJP site. All data were collected during the summer of 1994. Note that the TE-07 dendrology data available for the ORNL DAAC are a summary and an inventoru of the full Canadian Forest Service (CFS) data set. Please see Section 1.5 of the complete data set reference document for information on obtaining the CFS data set. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE07DEND ]

  • The gas exchange data of the Boreal Ecosystem-Atmosphere Study (BOREAS) Northern Study Area (NSA) were collected to characterize diurnal gas exchange and water potential of two canopy levels of five boreal canopy cover types: young and old jack pine (Pinus banksiana Lamb.), old aspen (Populus tremuloides Michx.), and lowland and upland black spruce (Picea mariana (Mill) B.S.P.). These data were collected between 27-May-1994 and 17-Sep-1994. The purpose of this study was threefold: 1) to provide in situ gas exchange data that will be used to validate models of photosynthetic responses to light, temperature, and carbon dioxide (CO2); 2) to compare the photosynthetic responses of different tree crown levels (upper and lower), and 3) to characterize the diurnal water potential curves for these sites to get an indication of the extent to which soil moisture supply to leaves might be limiting photosynthesis. [ This document was provided by NASA's Global Change Master Directory. For more information on the source of this metadata please visit http://gcmd.nasa.gov/r/geoss/[GCMD]BOREAS_TE09GXDA ]

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