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NPP Grassland: Hays, USA, 1970, R1

Data Set Overview

Data setNPP Grassland: Hays, USA, 1970, R1
Release date2014-07-29
ProjectNet Primary Productivity (NPP)
Time Period1867-01-01 to 1994-12-31


This data set contains three ASCII files (.txt format). Two files contain above- and below-ground biomass and productivity data for a mixed prairie grassland, one file for an ungrazed treatment and the other for a moderately grazed treatment. The study site (38.87 N, - 99.38 W, Elevation 714 m) is located in the central Great Plains near the city of Hays, Kansas, about 400-km west of Kansas City. The third file contains monthly and annual climate data for the period 1891-1994 obtained from a weather station (38.87 N, -99.38 W, Elevation 613 m) located at the Hays grassland study site. Dynamics of above-ground living and dead plant biomass were monitored by the harvest technique at roughly 2-week intervals during the growing season of 1970. Total below-ground biomass was sampled at the same intervals by manual coring within the harvested plots to a depth sufficient to include at least 90% of the root mass. Data were collected as part of a coordinated study over 1-3 years at ten grassland sites of the central and western United States, under the US Grassland Biome Project of the International Biological Program (IBP). Annual above-ground net primary production (ANPP) was estimated conservatively by summing peak biomass of individual species. These values were 363 g/m2/year for ungrazed and 372 g/m2/year for grazed grassland plots. Annual below-ground net primary production (BNPP) was estimated as the sum of positive increments in total root biomass (including root crowns); 1,062 g/m2/year for ungrazed and 855 g/m2/year for grazed grassland plots.


Data set reference document


Hulett, G.K., and G.W. Tomanek. 2014. NPP Grassland: Hays, USA, 1970, R1. ORNL DAAC, Oak Ridge, Tennessee, USA.
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Net Primary Productivity (NPP): NPP (net primary production) data from existing field measurements are being compiled for approximately 100 study sites covering several major world ecosystem types. These data are used by global change modelers to develop and validate models of vegetation-soil-atmosphere interactions within the global carbon cycle and to help calibrate remote sensing of vegetation worldwide

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Companion Files

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  • NPP_HYS.pdf

Data Files

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Data File (Granule)File SizeDates
hys_cli.txt 45.8 KB 1867-01-01 - 1994-12-31
hys1_npp.txt 3.3 KB 1970-01-16 - 1970-11-15
hys2_npp.txt 3.3 KB 1970-01-16 - 1970-12-18


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Files related to this data set have been downloaded on 210 occasions since 2007-12-06, totaling 1075 files.