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biota

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  • Estimates of root turnover rates were calculated from measurements of live root standing crop and belowground net primary production (BNPP) compiled from the primary literature. Vegetation characteristics, soil properties, and climate conditions were associated with turnover rates to examine patterns and controls for biomes worldwide. Building on prior analyses (Jackson et al. 1996, 1997), data were compiled from approximately 190 papers from additional journals, book chapters, technical reports, and unpublished manuscripts that included information on live root standing crop and belowground BNPP. The papers described research on every continent except Antarctica, although the majority were from North America. In the database, the plant functional type and biome coverage were most abundant for grasslands and temperate zones. [ 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_turnover ]

  • 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 ]

  • The BOREAS TF-11 team collected several data sets in their efforts to fully describe the flux and site characteristics at the SSA-Fen site. This data set contains plant cover, standing crop of plant biomass, and estimated net primary productivity at each chamber site at the end of the 1994 field season. The measurements were conducted as part of a 2x2 factorial experiment in which we added carbon (300 g m-2 as wheat straw) and nitrogen (6 g m-2 as urea) to four replicate locations in the vicinity of the TF-11 tower. [ 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_TF11BIOM ]

  • 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 ]

  • The BOREAS TF-11 team collected several data sets in their efforts to fully describe the flux and site characteristics at the SSA-Fen site. This data set contains decomposition rates of a standard substrate (wheat straw) across treatments. The measurements were conducted as part of a 2x2 factorial experiment in which we added carbon (300 g m-2 as wheat straw) and nitrogen (6 g m-2 as urea) to four replicate locations in the vicinity of the TF-11 tower. [ 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_TF11DCOM ]

  • 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 ]

  • The purpose of these measurements was to determine plot-level average leaf concentrations of nitrogen, lignin, cellulose, etc. in order to investigate how AVIRIS reflectance measurements vary with chemistry. The plot-level leaf chemistry values were calculated from green leaf chemistry values and litterfall sample weights. [ 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_PLOTCHEM ]

  • 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 foliar 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_TE2FLRSP ]

  • 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 ]

  • This data set contains leaf area index (LAI), leaf inclination angle, and canopy dimension data from study sites along the Kalahari Transect in southwest Botswana. The data were collected during the 2001 wet season field campaign of the SAFARI 2000 at a total of seven plots of 200 x 150 meter dimensions; two plots each at Tshane and Mabuasehube, and three plots at Tsabong. The data set consists of measurements of leaf angle for plot dominant woody species, LAI calculated from overstory and understory photosynthetically active radiation (PAR) measurements, and canopy dimension data (i. e., crown height, crown width, and height to crown) for grass and woody vegetation, for use in the parameterization of plant canopy reflectance models.Measurements of LAI were made with a plant canopy analyzer which records direct and diffuse PAR at the top of the canopy using a beam fraction sensor. PAR beneath the canopy was measured simultaneously with a one-meter long probe held horizontally beneath the canopy. Leaf inclination angle measurements were made using a clinometer. Measurements of tree height, crown height, height-to-crown, and crown width were made for 10 to 20 individual trees of the dominant species at each field plot using a tape measure or simple trigonometry, and calculations based on these data.The data files are stored as ASCII table files, in comma-separated-value (.csv) format, with column headers. Photographs (.jpg) are provided of each plot to provide an idea of site conditions. The photographs can be viewed on the S2K Photo Gallery pages. [ 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_canopy_struc ]

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