Grantee Research Project Results
The Detritivores of Semiarid African Savannas: Community and Ecosystem ProcessesEPA Grant Number: U915805
Title: The Detritivores of Semiarid African Savannas: Community and Ecosystem Processes
Investigators: Schuurman, Gregor W.
Institution: University of Washington - Seattle
EPA Project Officer: Broadway, Virginia
Project Amount: $102,000
RFA: STAR Graduate Fellowships (2000)
Research Category: Fellowship - Terrestrial Ecology and Ecosystems , Academic Fellowships , Ecological Indicators/Assessment/Restoration
The objective of this research project is to understand how biota affect ecosystem function. Achievement of this objective relies on a solid understanding of each fundamental biotic component.Approach:
No ecosystem can function without decomposers, which convert dead organic matter into nutrients available for plant growth. Despite universally acknowledged importance, decomposers are ignored in most studies on how community traits and processes influence ecosystem function. This bias, in favor of other trophic levels (usually plants and/or herbivores), is a consequence of the fact that most decomposer communities are difficult to study and manipulate because of their tremendous taxonomic diversity and microscopic size.
As a first step in overcoming practical obstacles, I have selected a study site, the Okavango Delta region of northern Botswana, where the semiarid climate restricts microbial decomposition to a relatively brief portion of the year, and excludes most soil macrofauna, except termites. Termites, particularly members of the fungus-growing subfamily Macrotermitinae, thrive in this climate and dominate decomposition in some habitats. Using this relatively simple decomposer community, dominated by large bodied, readily identifiable species, I am investigating the roles of individual species, functional groups, and overall diversity in regulating decomposition. I also am interested in how soil properties and climate influence where various species and functional groups are found. I hope to show how differing decomposition rates caused by the presence or absence of termites (or functional groups of termites) affects soil nutrient status and ultimately influence plants, herbivores, and predators.Supplemental Keywords:
fellowship, detritivoves, African savannas, Botswana, ecosystem, decomposers, termites, dead organic matter, Macrotermitinae, ecosystem function.