Investigating the effects of vegetation and location on macroinvertebrate community composition in Grass Bay Nature Preserve, Cheboygan County, Michigan

Abstract

Wetlands provide a variety of ecosystem services to humans, as well as providing habitat to organisms such as macroinvertebrates. Macroinvertebrates are ecologically important as water quality indicators, since their distribution is largely influenced by factors like water temperature, pH, dissolved oxygen, and substrate availability. In the following study, macroinvertebrate richness, evenness, and abundance was tested in an inland (enclosed) and coastal (open) freshwater fringe marsh, both in vegetated and non-vegetated areas to determine if there could be finer distinctions within fringe wetlands. Few prior studies have examined these differences within wetland types, specifically in fringe marshes. No significant difference was found between the Shannon-Wiener Diversity Index (E) values for richness or the Simpson’s Diversity Index (D) values for evenness in the four total areas. However, there was significantly greater macroinvertebrate abundance in the enclosed marsh compared to the open marsh, and in vegetated compared to non-vegetated areas. Macroinvertebrate abundance was highest in the enclosed-vegetated site. These results may indicate location-specific factors affect abundance of macroinvertebrate communities. Determining how macroinvertebrate community composition differs between environments can yield important information for predicting water quality and future changes in communities due to climatic changes or anthropogenic factors in these environments. This information can be made more site-specific based on this study’s finer look at communities within fringe marshes.