Landscape impacts on fish community structure and food chain length in Prairie and Ozark Rivers.

摘要

Rivers in the Ozark Highland ecoregion and Central Prairie ecoregion differ in land use and diversity, and these could impact food chain length. The primary factors controlling food chain length are not certain, but were considered. Fish and invertebrates were collected for stable isotope analysis and analyzed for trophic position. Land use was measured using remote sensing. Fish community structure was correlated to land use, but not necessarily to water quality. In particular, it appears that the amount of forest or agriculture is very important in determining fish and invertebrate stream community composition. Food chain length was related to neither the predicted hypotheses nor community structure. However, members of the family Cyprinidae were very common, and rivers where few cyprinids were captured had low food chain length. Food chain length is driven by many processes and the effects of landscape should be considered.; Key Words: trophic position, land use, fish.