Milchunas, Daniel G.2007-01-032007-01-031985-2007http://hdl.handle.net/10217/85665http://dx.doi.org/10.25675/10217/85665Natural Resource Ecology Laboratory (NREL)Shortgrass Steppe-Long Term Ecological Research (SGS-LTER)This data package was produced by researchers working on the Shortgrass Steppe Long Term Ecological Research (SGS-LTER) Project, administered at Colorado State University. Long-term datasets and background information (proposals, reports, photographs, etc.) on the SGS-LTER project are contained in a comprehensive project collection within the Repository (http://hdl.handle.net/10217/100254). The data table and associated metadata document, which is generated in Ecological Metadata Language, may be available through other repositories serving the ecological research community and represent components of the larger SGS-LTER project collection. The belowground system in arid and semiarid regions can be of relatively greater importance than in more mesic systems because plant competition is most often for soil water rather than for light in aboveground canopies. Belowground plant biomass in the shortgrass steppe represents approximately 80% of the total. These data, entitled Long-Term Seasonal Root Biomass, were obtained in section 21 of the Central Plains Experimental Range from 1985-2008 in conjunction with a 14C labeling experiment designed to test isotope methods of estimating root production. Paired plots for each of eight replicate 14C labeled plots were established and cored on average six times per year over 13 years (five cores each plot each date as above). There were two primary objectives for collecting these data, 1) to compare estimates of root production (or belowground net primary production - BNPP) obtained using the sequential coring of biomass methods with various isotope, minirhizotron, ingrowth, and other methods, and 2) to examine long-term controls on the temporal dynamics of root biomass. This shortgrass steppe LTER site is the only place we are aware of that has compared most methods of estimating BNPP, including sequential coring, ingrowth cores, and ingrowth donuts, 14C pulse-isotope dilution, 14C pulse-isotope turnover, rhizotron windows, and minirhizotron, and indirect methods including nitrogen budget, carbon flux, simulation carbon flow model, and regression model. All production methods are compared in Milchunas (2009), and more detailed comparisons among particular methods can be found in Milchunas and Lauenroth (1992, 2001), and Milchunas et al. (2005a, and 2005b). Results and conclusions concerning root biomass dynamics and relationships with precipitation, season, and aboveground biomass are reported primarily in Milchunas and Lauenroth (2001).ZIPPDFTXTXMLengData sets were provided by the Shortgrass Steppe Long Term Ecological Research (SGS-LTER) Program, a partnership between Colorado State University, United States Department of Agriculture, Agricultural Research Service, and the U.S. Forest Service Pawnee National Grassland. Significant funding for these data was provided by the National Science Foundation Long Term Ecological Research program (NSF Grant Number DEB-1027319). The SGS-LTER project (1980-2014) was established as one of the first sites in the US LTER Network and has produce a rich legacy of digital materials including reports, proposals, images, and data packages. Data, products and other information produced from the SGS-LTER are curated as a collection within the Repository (http://hdl.handle.net/10217/100254). Materials can be accessed from the Institutional Digital Repository of Colorado State University or upon request by emailing ecodata_nrel@colostate.edu. All data are open for dissemination and re-use for any purpose, but you must attribute credit to the owner and cite use appropriately according to the LTER Data Access Policy (http://www.lternet.edu/policies/data-access).primary productionpopulation dynamicsbelowground net primary productionbiomassplantsDataset