Multivariate Analysis of Rangeland Vegetation and Soil Organic Carbon Describes Degradation, Informs Restoration and Conservation

摘要: Agricultural expansion has eliminated a high proportion of native land cover and severely degraded remaining vegetation. Managers must determine where degradation is severe enough to merit restoration action, what if any, necessary. We report on grassland by multiple factors, including grazing, soil disturbance, exotic plant species introduced in response agriculture management. use multivariate method categorize communities state based floristic biophysical associated with historical use. The variables we associate include abundance the invasive cool-season grass, tall fescue (Schedonorus phoenix (Scop.) Holub); organic carbon (SOC); heavy livestock grazing. Using series analyses (ordination, hierarchical clustering, regression), identify patterns community composition describe states. found vegetation states be described largely primarily secondarily but not carbon. Categorizing grasslands helps managers efficiently apply inputs that optimize ecosystem response, so discuss potential pathways state-and-transition model. Reducing stocking rate grazing actively practiced an important first step might sufficient for restoring richness minimal from plants. More likely requires approaches reverse degradation. Of these, recommend ecological processes disturbance regimes such as fire suggest old-field North America, which are similar European semi-natural function, deserve more attention conservation biologists.