Trophic cascades, which are predator-initiated interaction pathways producing indirect effects in food webs, can influence rates of basic ecosystem processes such as plant productivity and leaf-litter decomposition. Theory predicts that the high diversity of generalist predators in terrestrial food webs should severely dampen control processes involving trophic cascades. Some results of the PI's research program support these predictions, whereas other findings fail to confirm theory. By utilizing several statistical techniques to synthesize and integrate experimental results, the proposed research will identify major pathways of trophic cascades and reveal how variation in climatic variables may affect control processes involving these pathways.
The scientific insights generated by the research relate directly to several challenges facing contemporary society: (1) understanding how biodiversity and food-web dynamics are related, which is critical to developing programs in biodiversity conservation; (2) understanding how generalist predators can be utilized to control insect pests in agriculture, leading to reduced reliance on pesticides; and (3) understanding how changes in climate may affect species interactions that alter litter decomposition and nutrient cycling in forest ecosystems. The research will strengthen the infrastructure of science by introducing a graduate student in statistics to contemporary ecological research.