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  • The BOREAS TE-11 team collected several data sets in support of its efforts to characterize and interpret information on the sap flow, gas exchange, and lichen photosynthesis of boreal vegetation and meteorological data of the area studied. This data set contains measurements of sap flow conducted at the SSA-OJP site in the growing seasons of 1993 and 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_TE11SAPF ]

  • The NPP Database contains documented field measurements of NPP for global terrestrial sites compiled from published literature and other extant data sources. The NPP Database contains biomass dynamics, climate, and site-characteristics data georeferenced to each intensive site. A major goal of the data compilation is to use consistent and standard well-documented methods to estimate NPP from the field data. Other important components of the database include a summary, investigator contact information, and a list of key references for each site. As far as possible, the original principal investigator or his/her successor has been contacted to review the data and documentation. The NPP Database currently contains detailed data for over 60 intensive study sites. A majority of these sites are grasslands, the remainder being tropical forests, boreal forests, and tundra study sites. Some combination of above-ground annual peak live biomass data and/or seasonal biomass dynamics data are available for all sites. Many sites also have data on below-ground biomass and/or turnover. Estimates of net primary productivity are included, where available, for individual sites, and as part of the NPP Summary tables. Climate and soils data are available for all sites in varying degrees of detail. The sites have been grouped according to vegetation maps based upon Bailey ecoregions, Holdridge Life-Zones, Matthews vegetation classes, and Olson World Ecosystem Complexes. Previously compiled multi-site data sets of georeferenced NPP estimates are also provided. NPP estimates are available from a number of different collections, containing more than 1700 sites but with less information available for each individual site as compared to the intensive sites. Records for these sites typically include an NPP value, latitude and longitude, original source of the data, and sometimes information on vegetation type, management, soils, and local climate. More information on the entire Net Primary Productivity Project can be found at the NPP home page, with links to further details on individual study sites or multi-site collections. Users are encouraged to browse these Web pages to find details of original studies, methodologies, and original research contacts. NPP data are available on-line from the ORNL Distributed Active Archive Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, U.S.A. Data Citation: Cite the data sets using the following reference format: Author, P. A., and M. B. Author. Year. Data Set Title. Available on-line from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. For example: Williamson, P., and J. Pitman. 1999. NPP Grassland: Beacon Hill, U.K. 1972-1973. Available on-line from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. [ 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]GPPDI ]

  • The Vegetation-Ecosystem Modeling and Analysis Project (VEMAP) was a large, collaborative, multi-institutional, international effort whose goal was to evaluate the sensitivity of terrestrial ecosystem and vegetation processes to altered climate forcing and elevated atmospheric CO2. Phase 1 of the VEMAP project developed historical (1895-1993) data sets of observed climate, soils, and vegetation compatible with the requirements of ecosystem models and vegetation distribution models. See the VEMAP Phase 1 User's Guide for more information.Phase 2 developed historical (1895-1993) gridded data sets of climate (temperature, precipitation, solar radiation, humidity, and wind speed) and projected (1994-2100) gridded annual and monthly climate data sets using output from two climate system models (CCCma (Canadian Centre for Climate Modeling and Analysis) and Hadley Centre models). See the VEMAP Phase 2 User's Guide for additional background information.Two Phase 2 model experiments were run. First, a set of selected biogeochemical models and coupled biogeochemical-biogeographical models were run from 1895 to 1993 to compare model responses to the historical time series and current ecosystem biogeochemistry. Second, these same models were run on the projected 1994 to 2100 data to compare their ecological responses to transient scenarios of climate and atmospheric CO2 change. Model runs were performed for daily, monthly, and annual gridded data sets. The output of the monthly model runs in VEMAP grid format are contained in this data set.The models investigated included five biogeochemical cycling models, which simulate plant production and nutrient cycles, but rely on a static land-cover type, and two dynamic global vegetation models (DGVMs) that combine biogeochemical cycling processes with dynamic biogeographical processes including succession and fire simulation.Biogeochemical Cycling ModelsBiome-BGC (BioGeochemical Cycles)CenturyCentury rxveg GTEC (Global Terrestrial Ecosystem Carbon Model)TEM (Terrestrial Ecosystem Model)Dynamic Global Vegetation ModelsLPJ (Lund-Potsdam-Jena MC1 (MC 5 modified Century)VEMAP 2 model intercomparison results have been published by Schimel et al.(2000), Bachelet et al. (2003) and Gordon and Famiglietti (2004). Related Data SetsAvailable on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center.VEMAP 2: U.S. ANNUAL CLIMATE, 1895-1993 VEMAP 2: U.S. MONTHLY CLIMATE, 1895-1993, VERSION 2 VEMAP 2: U.S. DAILY CLIMATE, 1895-1993 VEMAP 2: U.S. ANNUAL CLIMATE CHANGE SCENARIOS VEMAP 2: U.S. MONTHLY CLIMATE CHANGE SCENARIOS, VERSION 2 VEMAP 2: U.S. DAILY CLIMATE CHANGE SCENARIOS VEMAP 2: Annual Ecosystem Model Responses to U.S. Climate Change, 1994-2100. [ 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]vemap2_monthly_rslts ]

  • The focus of this study was to quantify the effects of foliage removal by cattle on plant net primary productivity (NPP). The Vegetation Biomass, Production and Consumption at Selected Sites Data Set contains mean values and their variances. During the growing season of 1987, portable cattle exclosures were used to quantify above-ground plant biomass dynamics at each of four sites. All sites had been grazed each year and burned frequently during the preceding 10 years. Biomass was measured inside portable exclosures, outside exclosures (in unprotected vegetation), and inside permanent exclosures. Exclosures were moved to previously unsampled locations within a distance of 10 m after samples were obtained, and these remained in place until the next sampling date. [ 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]FIFE_PLANTPRO ]

  • Nutrient measurements for fine roots were compiled from 56 published studies providing information on 372 different combinations of species, root diameter, rooting depths, and soils at a variety of locations. The compilation was used to examine dynamics of 14 nutrients, including translocation properties of roots of varying size and status.Fine roots are an important source and sink for nutrients in terrestrial biogeochemistry. The data collected come from 56 published studies that give information on fine root (less than 5mm diameter) nutrient concentrations, root diameters, and retranslocation of nutrients. These studies include diverse vegetation and biomes, including grass, shrub, and tree functional types from temperate, tropical, boreal and tundra systems. The preponderance of data comes from experiments with temperate and coniferous trees. [ 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]root_nutrients ]

  • This data set contains contains two ASCII files. One file, in comma-separated-values (.csv) format, provides above-ground net primary production (ANPP) and total NPP [expressed in grams of carbon per square meter per year (gC/m2/year)] and the C fraction used to convert dry biomass weight to carbon content for 127 unique study sites in northern Eurasia. The sites are classified by ecozone (i.e., tundra, forest-tundra, taiga, mixed forest, broadleaf forest, small-leaved secondary forests, forest bogs, meadows, steppe, semi-desert, and polar desert) and plant community (phytocoenosis). Each study location is georeferenced (latitude/longitude) with elevation and zonal/interzonal information. References to original author, year of publication, and table/record in Bazilevich (1993) are also included in the data file. The second ASCII file, in text (.txt) format, provides the bibliography of 274 original-source references (in Russian) to accompany the 127 data records on NPP from Bazilevich (1993). The data are a subset of data adapted from Bazilevich, N.I. 1993. Biological Productivity of Ecosystems of Northern Eurasia. Nauka Publishers, Moscow. 293 pp. (in Russian). The data set originated from field measurements of primary productivity collected between 1940 and 1988 for most of the terrestrial vegetation types in northern Eurasia. [ 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_BAZ ]

  • The BOREAS RSS-17 team acquired and analyzed imaging radar data from the ESA's ERS-1 over a complete annual cycle at the BOREAS sites in Canada in 1994 to detect shifts in radar backscatter related to varying environmental conditions. This data set consists of dielectric constant profile measurements from selected trees at various BOREAS flux tower sites. The relative dielectric constant was measured at C-band (frequency = 5 GHz) as a function of depth into the trunk of three trees at each site. Measurements were made during April 1994 with an Applied Microwave Corporation field PDP fitted with a 0.358-cm (0.141-inch) diameter coaxial probe tip. [ 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_RS17DIEL ]

  • This data set describes the nitrogen and chlorophyll content of small, monospecific canopies formed from seedlings of Douglas-fir (Pseudotsuga menziesii) and bigleaf maple (Acer macrophyllum). The trees were provided different levels of fertilization in order to produce canopies with varying nitrogen and chlorophyll concentration. For the Douglas-fir, fertilization was provided during the dormant season, so there were no differences in growth or leaf area among canopies, and canopies were at a constant density with varying foliar chemistry. For the maple, seedlings were aggregated at various densities, producing a matrix of leaf area as well as chemistry variations. Before destructive analysis for foliar chemistry, canopy reflectance was measured under natural sunlight (see ACCP Seedling Canopy Reflectance Spectra Data). [ 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]ACCP_CANOPYCHEM ]

  • Vegetation cover and composition, including species types and richness assessments, were measured at four locations along the Kalahari Transect in Botswana (Pandamatenga, Maun, Okwa River, and Tshane) during the SAFARI 2000 wet season field campaign. The sites visited showed interesting degrees of variability despite the apparent homogeneity of the Kalahari sands and predominantly semi-arid savanna shrub-woodlands vegetation cover (Ringrose et al., 2003).At each site, twelve individual locations were chosen by random stratified techniques within a 30-km radius at each location, based on differences in topography, soils, and known disturbance, to help determine local variability (Huennecke et al., 2001). Data collection methods were identical at each location (Ringrose et al., 1996; 1998): (1) identification and enumeration of all species along 3 x 90-m transects, spaced 45-m apart; (2) visual estimation (tape measure and pacing) of canopy diameter along each transect; and (3) visual estimation of percent live and dead herbaceous cover, litter, and bare soil using 3 x 50 m2 quadrats spaced at 30-m intervals along each transect. In addition, vegetation components were calculated for each site comprising woody vegetation cover, green herbaceous cover in terms of grass and forbs, dead herbaceous cover, plant litter, and bare soil. Species richness was calculated as the actual number of species per three transects (270 m2) at each site (Kent and Coker, 1996).The data set consists of two data files (ASCII tables) in comma-delimited format (.csv) with descriptive header records. [ 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_kt_veg_inv ]

  • A global data set of root biomass, rooting profiles, and concentrations nutrients in roots was compiled from the primary literature and used to study distributions of root properties. This data set consists of estimates of fine root biomass and specific area, site characteristics, and source references associated with two papers (Jackson et al. 1996 and 1997).Understanding and predicting ecosystem functioning (e.g., carbon and water fluxes) and the role of soils in carbon storage requires an accurate assessment of plant rooting distributions. [ 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]rootfine_biomass1997 ]

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