Ecosystem development and the maintenance of diversity appears to be a function of the strength of linkages among plants and decomposers and the influence that the linkages have on nutrient availability. The lodgepole pine forest and adjacent mountain meadows near Fox Park, WY, are ecosystems that differ in structure and function, yet share a common climate, similar topography, and have developed on soils derived from the same parent materials. Recent work at the sites suggests that the linkages among plants and decomposers are specialized to the substrates, soils and microclimate of their own ecosystem. Two manipulative field studies and a series of laboratory studies will be conducted to determine how specific the plant-decomposer linkages are, and the mechanisms that shape and preserve them. The "Canopy Manipulation Study" will determine the influences that canopy structure, litter quality, and soil properties have on decomposer food web structure and nitrogen dynamics of the lodgepole pine forest and adjacent meadow. The "Decomposer Deletion Study" will test whether competitive exclusion among decomposers or habitat alteration are the mechanisms that maintain the integrity of each system. The Laboratory studies will investigate the range of substrates that decomposers from the meadow and forest utilize, and the soil and climatic conditions under which the dominant isolates from each system optimally grow and reproduce.
