COLLABORATIVE RESEARCH: Decomposition in drylands: Soil erosion and UV interactions

New Mexico State University, Las Cruces NM

Investigators

Abstract

Decomposition, the breakdown of dead plant and animal material, is a fundamental process that affects soil fertility and ecosystem carbon storage. Most of what is known about decomposition is from studies in high rainfall areas, but this knowledge does not translate well to dryland ecosystems. Some recent studies suggest solar ultra-violet radiation has a major influence on decomposition in drylands; however, other studies indicate the level of mixing of wind/water-transported soils with litter is the key factor. This project seeks to resolve these competing explanations through a series of laboratory studies and field experiments in Arizona designed to measure interactions among these factors. These linkages will be assessed in the context of woody plant encroachment into grasslands, a globally extensive vegetation change in drylands. This investigation will yield new insights into processes that affect soil fertility and carbon storage in drylands by combining the disciplines of plant community ecology, ecosystem science and earth science in a novel framework. The findings will be relevant nationally and internationally, as dryland ecosystems characterize major portions of the US and global land area, and may be significant carbon sinks. In addition to dissemination in the scientific community, results will be communicated to land management personnel and organizations through outreach programs. The study will provide training opportunities for four graduate and numerous undergraduate students. The collaborating institutions (University of Arizona, New Mexico State University, University of Kentucky and Loyola University) have substantial minority enrollments, and efforts will be made to recruit students from underrepresented groups.