The Indirect Effects of Ultraviolet-B Radiation on the Composition and Decomposition of Leaf Litter From a Diverse Group of Plants

最近平流层臭氧的减少可能使本地植物暴露于更高水平的紫外线b辐射（UV-B）。虽然有许多研究调查了UV-B对农业植物的潜在破坏性影响，但很少有研究调查UV-B如何影响本地植物或重要的生态系统过程。在这个项目中，将进行两个实地实验，以确定UV-B是否会改变本地植物的化学成分，从而改变植物组织分解释放养分的速度。植物组织的分解是自然生态系统中植物养分的主要来源，分解速率的变化会显著影响土壤肥力。6种本地植物将在对应于平流层臭氧减少0%、16%和32%的UV-B水平下生长。去除正常水平的UV-B的效果也将被检查。该项目的数据将用于测试现有的土壤养分动态模型。然后，这些模型将用于评估UV-B的重大变化是否可能对土壤肥力产生重要影响。

9603659 Peterjohn Recent declines in stratospheric ozone may expose native plants to greater levels of ultraviolet-B radiation (UV-B). While numerous studies have investigated the potentially damaging effects of UV-B on agricultural plants, few studies have examined how UV-B affects native plants or important ecosystem processes. In this project, two field experiments will be conducted to determine whether UV-B changes the chemical composition of native plants in ways that alter the rate of nutrient release from decomposing plant tissue. Decomposition of deal plant tissue is the major source of plant nutrients in natural ecosystems, and changes in the rate of decomposition may significantly alter soil fertility. Six species of native plants will be grown under UV-B levels corresponding to a 0, 16, and 32% decrease in stratospheric ozone. The effect of removing normal levels of UV-B will also be examined. Data from this project will be used to test existing models of soil nutrient dynamics. These models will then be used to evaluate whether the effects of a major change in UV-B are likely to have an important impact on soil fertility.