UV Litter Decomposition: The role of photodegradation in surface litter decomposition in grasslands along UV-B gradient

Process-based models of plant litter decomposition typically underestimate the rates of decomposition in arid and semi-arid grasslands. Recent research, including our field studies, suggests that photodegradation, the decomposition of material through solar radiation, may play an important role in arid and semi-arid grassland ecosystems. The contribution of photodegradation to overall rates of decomposition is not well understood or quantified. The goal of this project is to investigate the effects of ultraviolet radiation on rates of plant litter decomposition for two grass species, Andropogon gerardii and Bouteloua gracilis, in three grassland sites: Cedar Creek (MN), Shortgrass Steppe (CO), and Sevilleta (NM).基于过程的植物枯落物分解模型通常会低估干旱与半干旱草原生态系统中的枯落物分解速率。近期相关研究（含本团队的野外实地研究）表明，光降解（photodegradation）——即通过太阳辐射实现的物质分解过程——在干旱与半干旱草原生态系统中可能发挥着重要作用。目前，光降解对总分解速率的贡献尚未得到充分阐明与量化。本项目的研究目标为：探究紫外辐射对两种草本植物——须芒草（Andropogon gerardii）与格兰马草（Bouteloua gracilis）——枯落物分解速率的影响，实验样地涵盖三处草原站点：雪松溪（Cedar Creek, MN）、短草草原（Shortgrass Steppe, CO）以及塞维列塔（Sevilleta, NM）。