Herbage dynamics and net primary production in certain ungrazed and grazed grasslands of North America

TitleHerbage dynamics and net primary production in certain ungrazed and grazed grasslands of North America
Publication TypeConference Proceedings
Year of Publication1971
AuthorsSims P.L., Singh J.S
EditorFrench NR(ed.)
Conference NamePreliminary Analysis of Structure and Function in Grasslands: Proceedings of Symposium Entitled "The Grassland Biome: Analysis and synthesis of First Year Data"
Series TitleRange Science Department Science Series 10
Date PublishedSeptember 1, 197
PublisherColorado State University
Conference LocationColorado State University, Fort Collins, Colorado
Keywordsabstract, abstracts, biomass,grassland, conference, conference proceedings, conferences, grassland,abiotic factors, grassland,biomass, grassland,herbage dynamics, grassland,primary production, grazing,herbage dynamics, grazing,primary production, primary production,grassland, proceeding, proceedings
Abstract Nine U.S. IBP Grassland Biome sites are characterized according to the abiotic and vegetational characteristics and their relationship to grazed and ungrazed conditions by analysis and synthesis of 1970 field data. Abiotic characteristics including length of growing season, usable solar radiation, mean annual temperature, mean annual precipitation, potential and actual evapotranspiration, and aridity indices are used to interpret intraseasonal herbage dynamics and net primary productivity. Snythesis of vegetation data involved categorization of plant species into cool and warm season vegetation classes (grasses, forbs, shrubs, and succulents) and into compartments by live, current year's dead, old dead, litter, and belowground plant meterial. The belowground biomass is characterized according to the seasonal average and peak biomass, percentage of total plant biomass situated belowground, and the vertical distribution of this material. Annual increment and turnover rates are presented. The relationship of these charcteristics to abiotic factors is examined. Estimated net primary productivity and accumulation rates are calculated for ungrazed and grazed grasslands on each site. These data are further analyzed by evaluation of system transfer functions and efficiency of energy capture by various vegetation compartments.
Custom 1Fort Collins, Colorado