Research Starter Grant: The Role of Soil Nitrogen in Plant Litter Decomposition

University Of Florida, Gainesville FL

Investigators

Abstract

Soil nitrogen (N) availability controls the decomposition of plant litter in two ways. First, it affects the quality or relative decomposability of litter through effects on plant growth and allocation. Second, soil N availability may directly limit the activity of decomposers. Because the Carbon (C) to N ratio of litter is usually higher than that of bacteria and fungi, these decomposers must immobilize N from the soil solution in order to use C in plant litter for metabolic activity and growth. The objective of this study is to develop a mechanistic understanding of how interactions between soil available N and plant litter quality affect decomposition using a novel method for measuring total N immobilization and loss during decomposition. This study will also provide information about the effects of fire on decomposition in boreal forest. Understanding how decomposition is altered by fire is key to understanding how ecosystem C balance may change with the increased fire frequency and intensity that is associated with anthropogenically-driven climate change. Finally, the mechanistic approach of this research should be make its findings generally applicable to understanding controls over decomposition in other systems.