Investigation of the relationship between aquatic macroinvertebrate distribution and abiotic and biotic factors in a northern Michigan river.

Abstract

Conditions in streams and rivers can vary greatly and influence species composition, especially that of macroinvertebrate communities. Functional feeding groups or guilds also have an impact on the distribution of different types of macroinvertebrates in rivers. This study analyzed how abiotic and biotic factors influenced macroinvertebrate distribution in a river. It was hypothesized that different abiotic and biotic conditions would produce differences in macroinvertebrate dispersal patterns. Four different sites along the Maple River near Pellston, MI were sampled. At these sites, rocks were chosen for anlaysis, a multitude of abiotic and biotic factors, and aquatic macroinvertebrates were classified to family and order and counted. Patterns were found in macroinvertebrate distribution, with temperature, water depth, rock size, filamentous green algae (FGA) cover, and flow rate accounting for most of the variation observed. Trends were also found between abiotic factors and between the presence or absence of different macroinvertebrates. Future studies should focus on perfecting the methods of this kind of study and expanding this analysis to different areas and aquatic ecosystems.