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  • The BOREAS TGB-07 team measured the concentration and flux of several agricultural pesticides in air, rainwater, and dry deposition samples in order to determine the associated yearly deposition rates. This data set contains information on the ambient air concentration of seven herbicides [2,4-dichlorophenoxyacidic_acid (2,4-D), bromoxynil, dicamb, 2-methyl-4-chlorophenoxyacetic acid (MCPA), triallate, trifluralin, and diclop-methyl] known to appear in the atmosphere of the Canadian prairies. Also, the concentration of three herbicides (atrazine, alaclor and metolachlor), two groups of insecticides (lindane and breakdown products and dichlro-diphenyl-trichloroethane (DDT) and breakdown products), and several polychlorinated biphenyls commonly used in the central United States were measured. All of these chemicals are reported, in the literature, to be transported in the atmosphere. Many have been reported to occur in boreal and arctic food chains. The sampling was carried out from June 16 to August 13, 1993 and May 4 to July 20, 1994 at the BOREAS site in the Prince Albert National Park (Waskesiu). [ 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_TGB7AAHO ]

  • This data set is an expanded version of the Costa et al. (2000) data set and consists of a single grid with values of 1 for cells within the basins and 0 for cells outside. The resolution of the data set is 5 x 5 min (approximately 9 x 9 km). The area of this data set is consistent with the study area of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) in South America. The data file is in ASCII GRID format. [ 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]lba_reg_basin ]

  • 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 ]

  • Annual mean aboveground wood increments for both hardwood and softwood are provided for 1956 counties of the 28 eastern U.S. states based on the forest inventory data from 1960s to 1990s. Estimates of aboveground production and mortality of woody biomass for forests of the eastern United States based on data collected from an extensive network of permanent inventory plots maintained by the U.S. Department of Agriculture Forest Service Forest Inventory and Analysis (FIA). Estimates of growing stock volume by forest type and stand size-class were compiled for 1,956 counties in the 28 Eastern states based on state-based inventories conducted between 1962 and 1988 with remeasurements conducted 6 to 23 years later between 1985 and 1996 (average interval of 12 years) (see Brown and Schroeder 1999). Inventory data were aggregated by county into three broad forest categories (hardwood, pine, and spruce-fir) and three stand-size classes and expressed per unit area of forest land. Forest area is defined by the Forest Service as land producing or capable of producing in excess of 20 cubic feet per acre per year of industrial roundwood products. Stand volume was converted to aboveground biomass with regression equations for biomass expansion factors (BEF; ratio of aboveground biomass density of all living trees to merchantable volume). The change in biomass and mortality between the two inventories was converted to an average net annual change in growing stock and mortality (MWB - mortality of woody biomass). APWB (aboveground production of woody biomass) was calculated as the sum of net annual growth and mortality of woody biomass. APWB is a major component of aboveground net primary production (ANPP). Statistics were presented for hardwood and softwood (pine plus spruce-fir) forest categories. The approach accounted for production of commercial and non commercial tree species with diameters greater than 2.5 cm and included noncommercial tree components (branches, twigs, and leaves) but did not account for annual leaf production. The estimation methods were based on work by Schroeder et al. 1997 and were also used to estimate woody biomass (Brown et al. 1999).Based on the analysis of the aboveground production data (Brown and Shroeder 1999), APWB for hardwood forests ranged from 0.6 to 28 Mg ha-1 yr-1 and averaged 5.2 Mg ha-1 yr-1. For softwood forests, APWB ranged from 0.2 to 31 Mg ha-1 yr-1 and averaged 4.9 Mg ha-1 yr-1. The correct spatial patterns of woody production estimates were published in Brown and Schroeder (2000). The corrected version of Figure 2 from Brown and Schroeder (1999) is included here as a companion file. Aboveground production of woody biomass was generally highest in southeastern and southern counties, mostly along an arc from southern Virginia to Louisiana and eastern Texas. No clear spatial pattern of mortality of woody biomass (MWB) existed, except for a distinct area of high mortality in South Carolina due to Hurricane Hugo in 1989. For hardwood forests, MWB ranged from 0 to 15 Mg ha-1 yr-1 and averaged 1.1 Mg ha-1 yr-1. The average MWB for softwood forests was 0.6 Mg ha-1 yr-1 with a range of 0-10 Mg ha-1 yr-1. The rate of MWB on an aboveground biomass basis averaged <1/yr for both hardwood and softwood forests. [ 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_woody_production ]

  • This dataset is a 1:2 million scale forest cover map for the land area of the Krasnoyarsk Region, Russia. Thirty-two land cover classes are distinguished. These data were digitized from maps of the Atlas of Forests of the USSR (Anon. 1973). This map should not be strictly viewed as a map of actual forest cover, but rather as a map of dominant tree species. Very few tree species are defined, and generally, each polygon and color has only one tree species assigned to it. [ 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]rlc_forest_cover ]

  • This data set contains two ASCII files (.txt format). One file provides ground-based biophysical measurements and above-ground net primary productivity (ANPP) estimates for 31 black spruce (Picea mariana) and 30 quaking aspen (Populus tremuloides) stands in Superior National Forest (SNF) in northeastern Minnesota, U.S.A. (-92 W 48 N). The measurements were obtained during a 1983-1984 intensive field campaign. Non-destructive measurements were made in over 100 forest plots covering a 50 x 50 km area. Sacrificed trees for biomass and annual increment measurements were taken outside the plots. The second file provides climate data from nearby weather stations for the period 1976-1986. The data set provides stand structural measurements (diameter at breast height, tree height, crown depth, and stem density), above-ground biomass, leaf area index, bark area index, and ANPP estimates. ANPP data are based on a combination of allometric relationships and annual tree-ring (radial) increments for the 5-year period 1979-1983. In the spruce stands, above-ground biomass ranged from 700-15,100 g/m2, LAI varied between 0.5-4.3, and ANPP ranged from 39-572 g/m2/yr. In comparison, above-ground biomass among aspen stands ranged from 600-22,000 g/m2, LAI varied between 1.3-4.0, and ANPP ranged from 213-1,199 g/m2/yr. The purpose of the SNF campaign was to investigate the ability of remote sensing to provide estimates of ecosystem biophysical properties. In addition to the results presented herein, satellite, aircraft, and helicopter observations and other ground measurements for the study sites are available from the ORNL DAAC Superior National Forest (SNF) Project web site [http://daac.ornl.gov/SNF/snf.shtml]. [ 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_SNF ]

  • 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]BCN_NPP ]

  • 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 wood respiration 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_TE2WDRSP ]

  • A newly developed ground-based canopy imaging system called an MVI was tested and used by the BOREAS TE-06 team to collect measurements of the canopy gap fraction (sky fraction), canopy gap-size distribution (size and frequency of gaps between foliage in canopy), branch architecture, and leaf angle distribution (fraction of leaf area in specific leaf inclination classes assuming azimuthal symmetry). Measurements of the canopy gap-size distribution are used to derive canopy clumping indices that can be used to adjust indirect LAI measurements made in nonrandom forests. These clumping factors will also help to describe the radiation penetration in clumped canopies more accurately by allowing for simple adjustments to Beer's law. Measurements of the above quantities were obtained at BOREAS NSA OJP site in IFC-2 in 1994, at the SSA OA in July 1995, and at the SSA OBS and SSA OA sites in IFC-2 in 1996. Modeling studies were also performed to further validate MVI measurements and to gain a more complete understanding of boreal forest canopy architecture. By using MVI measurements and Monte Carlo simulations, clumping indices as a function of zenith angle were derived for the three main boreal species studied during BOREAS. [ 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_TE6MLTVG ]

  • The BOREAS HYD-03 team collected several data sets related to the hydrology of forested areas. This data set contains measurements of snow depth, snow density in 3-cm intervals, an integrated snow pack density and snow water equivalent (SWE), and snow pack physical properties from snow pit evaluation taken in 1994 and 1996. The data were collected from several sites in both the SSA and the NSA. A variety of standard tools were used to measure the snowpack properties, including a meter stick (snow depth), a 100 cc snow density cutter, a dial stem thermometer and the Canadian snow sampler as used by HYD-04 to obtain a snow pack-integrated measure of SWE. This study was undertaken to predict spatial distributions of snow properties important to the hydrology, remote sensing signatures, and the transmissivity of gases through the snow. [ 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_H03SD96D ]

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