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  • Net primary production of a saline grassland was determined at the Montecillo study site belonging to Colegio de Postgraduados, Chapingo, near Mexico City, from 1984 to 1994. Monthly dynamics of live biomass and dead matter were monitored, above and below ground, 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 UNEP (United Nations Environment Programme) Project on "Primary productivity of grass ecosystems of the tropics" and continued under subsequent UNEP and UK-ODA (Overseas Development Administration) sponsored international projects. 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_MNT ]

  • ABSTRACT: Productivity of an ephemeral desert grassland was determined at the Badkhyz Nature Reserve Station in southern Turkmenistan, between 1948 and 1982. Monthly dynamics of above-ground plant biomass were made during the growing season (January-May) from 1948 to 1963, and the record of peak live biomass continues until 1982, with a gap from 1973 to 1976. 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_BDK ]

  • Productivity of a semi-desert steppe was determined at the Dzhanybek Research Station in Kazakhstan, between 1955 and 1989. A long time series of peak live biomass measurements are available from 1955 to 1989 (excluding 1976). More detailed data on the seasonal dynamics of above ground live biomass and dead matter are available for 1985-1989. 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_DZH ]

  • Productivity of old, unlogged stands of southern Appalachian cove forest was studied and compared to young stands. Tree growth increments and allometric relationships were the basis for estimation of NPP. Measurements of tree diameter at 1.37 m above ground were made at the beginning the study. Radial increment cores were taken from a subset of trees. Above-ground net primary production (ANPP) was estimated using regional species-specific allometric relationships for tree mass. Estimation procedures were outlined by Busing et al. (1993).Old stands of mixed deciduous (and mixed deciduous-Tsuga) were selected for their gentle terrain, accessibility and history of study. From 1988 to 1992, seven old-growth stands were sampled with plots (0.6-1.0 ha each). The total area of old-growth forest sampled was 5.4 ha. Radial increments over the previous decade were used to provide estimates of tree diameter growth. Young stands, dominated by the deciduous species Liriodendron tulipifera, provided comparative information.The climate is perhumid mesothermal with seasonal temperature variation, but precipitation is distributed throughout the year. The Gatlinburg SW, Tennessee station mean annual temperature is 13.2 degrees centigrade. Mean annual precipitation is 141 cm. Detailed long-term climate data for this station are available from the Southeast Regional Climate Center (http://www.dnr.state.sc.us/climate/sercc/). The Gatlinburg SW station is at 445 m asl, whereas the study sites are at elevations from 720 to 1140 m. The Alum Cave Bluffs Parking Area station at 1173 m asl is more representative of the study sites, but long-term data are not readily available. Shanks (1954), Stephens (1969), and Busing et al. (2005) have documented the 1947-1950 data from this station (http://water.usgs.gov/pubs/ds/2005/115/). Mean annual temperature is 9.9 degrees centigrade. Mean annual precipitation is 200 cm. Estimates of annual ANPP for stands of various ages ranged from 6 to 13 Mg/ha. Stand biomass of the old stands was high for temperate deciduous forests (>300 Mg/ha above ground); however, ANPP was average (6-10 Mg/ha/yr) and tended to be lower than that of young stands (12-13 Mg/ha/yr) on similar sites. [ 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_gsm ]

  • 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]NPP_NLS ]

  • Productivity of a "typical" steppe was determined at the Khomutovskaya Ukrainian Steppe Natural Reserve in Donezk Region, from 1967 to 1970. Measurement of monthly dynamics of above-ground plant biomass were made for each growing season (April-August/September). Cumulative above-ground net primary production was estimated for each year. 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 atthe 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_KHM ]

  • Productivity of an old stand of coast redwoods in northern California was studied via tree remeasurement (1972-2001) and allometric relationships. Measurements of tree circumference at 1.7 m above ground were made at the beginning and the end of the study. Above-ground net primary production (ANPP) was estimated using a range of specific gravities and several allometric relationships for tree volume. Trees lost to mortality over the study interval were included in the analysis. Reported data include site characteristics, redwood stand descriptors, and measured and calculated biomass and ANPP data.In 1972, Dr. Fujimori placed a 120 x 120 m plot (1.44 ha) in a particularly massive stand of coast redwoods on alluvial flats near Bull Creek in Humboldt Redwoods State Park, California (40.35 degrees N, -123.00 degrees W). At more than 1000 years of age, with trees greater than 90 m tall, the stand is relatively old and well developed. The climate is characterized by moderate temperatures, wet winters, and summers with low precipitation. Summer fog contributes to moisture input. The Scotia, California station mean annual temperature is 12.6 degrees centigrade. Mean annual precipitation is 123 cm. Detailed climate data for this station are available from the Western Regional Climate Center (http://www.wrcc.dri.edu/). A 1972 stem map of the stand allowed us to identify and remeasure trees > 10 cm in diameter. A range of tree biomass and ANPP estimates was obtained. Estimation procedures were outlined by Busing & Fujimori (2005).Estimates of annual ANPP ranged from 6 to 14 Mg/ha. However, ANPP values in the range from 7 to 10 Mg/ha were considered to be the most reasonable because of the accuracy of the particular equations, specific gravities and assumptions used to obtain them (Busing & Fujimori 2005). Stand biomass was extremely high (>3000 Mg/ha above ground); however, ANPP was not extreme. Photograph: The old-growth study stand in 2001. [ 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_busing_redwood ]

  • Productivity of a steppe grassland was determined at the Tumentsogt Research Station in Mongolia, between 1982 and 1990. Measurements were made of seasonal dynamics of above-ground live biomass for each year. The Mongolian steppe occupies a major part of eastern Mongolia and northern China, characterised by an arid continental climate with most rain falling between June and August. Land use is dominated by grazing, historically by nomadic pastoralists and more recently for cooperative livestock production. Private livestock grazing has been increasing since 1990. 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_TMN ]

  • Productivity of a steppe grassland was determined from 1980 to 1989 at the Inner Mongolia Grassland Research Station of the Chinese Academy of Sciences, within the Xilingol Biosphere Reserve. Measurements of above-ground live biomass, standing dead matter and litter were made bi-weekly from the beginning of May to early October for each year. Above-ground net primary production was estimated by summing peak live biomass of each of 5 species categories. Steppe grasslands of Leymus chinense and Stipa grandis are the dominant vegetation types, respectively, in the Eastern Eurasian steppe zone (semi-arid and sub-humid) and the middle Eurasian steppe zone (semi-arid). Both species provide good livestock forage and are used mainly as natural grazing lands, and both occur within the Xilingol reserve. 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_XLN ]

  • 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 ]

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