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Effects Of Long-Term Cattle Grazing And Woody Plant Encroachment On Soil Microbial Communities At The Santa Rita Experimental Range, Arizona, Cody Burton, Steven Archer, Rebecca L. Mcculley

Plant and Soil Sciences Presentations

Livestock grazing is considered a key driver of woody plant encroachment in dryland ecosystems worldwide. Woody plant establishment in these systems creates “islands of fertility,” in part by modifying erosional processes such that soil and plant litter are deposited beneath the shrub canopy, creating a nutrient rich soil/litter matrix that supports enhanced soil microbial biomass pools. In this study, we utilized a long-term grazing exclosure (>80 yrs) at the Santa Rita Experimental Range south of Tucson, Arizona and phopsholipid fatty acid analysis to quantify livestock grazing effects on soil microbial communities associated with the complex vegetative mosaic that characterizes …

Grasslands And Carbon: Processes And Trends, Rebecca L. Mcculley

Plant and Soil Sciences Presentations

Grasslands, which make up 30% of the U.S. land surface, store significant amounts of carbon belowground in roots and soils. Learn how disturbances such as drought, grazing, fire and tillage can significantly impact the grassland carbon balance.

Dr. Rebecca McCulley of the University of Kentucky, Dept. of Plant & Soil Sciences, talks about grasslands and the way they store and process carbon. Grasslands make up about 30 percent of the North American surface. Grasslands differ from forests in many ways, but from a carbon perspective they store a much greater proportion of the carbon than they take in in any …