Submitted to: Ohio Journal of Science
Publication Type: Abstract Only
Publication Acceptance Date: 1/31/2007
Publication Date: 3/1/2007
Citation: Smiley, P.C. 2007. Aquatic macroinvertebrate communities within agricultural drainage ditches and streams of the Upper Big Walnut Creek watershed, Ohio. The Ohio Journal of Science. 107:7. Interpretive Summary:
Technical Abstract: Drainage ditches are headwater streams that have been modified or constructed for agricultural drainage. These modified streams are a common landscape feature in Ohio, and constitute 25% of stream habitat within the state. Management of ditches focuses on removing excess water from agricultural fields without considering how these actions influence the aquatic biota. The objective of this study was to assess if macroinvertebrate communities differed between ditches and streams and among seasons. Macroinvertebrates were sampled from four sites in two ditches and two headwater streams within the Upper Big Walnut Creek watershed, Ohio, in the spring, summer, and fall of 2005. Three dipnet and three surber samples were collected from each site in each season. A two factor ANOVA coupled with the SNK test was used to determine if response variables differed among habitat types and seasons. Taxa richness was greater in streams than ditches (n = 12, p < 0.001). No difference in evenness occurred between habitat types. Abundance was greater in ditches than streams (n = 12, p < 0.001). EPT (Ephemeroptera Plecoptera Trichoptera) abundance was greater in streams than ditches in the spring (n = 4, p = 0.002), and no difference between habitat types occurred in other seasons. Differences in taxa richness, evenness, and abundance were not observed among seasons. The increased taxa richness and EPT abundance observed in streams suggests a need to manage ditches in the Upper Big Walnut Creek watershed for the conservation of macroinvertebrate communities.