An Examination of the Effects of a Reservoir, Lake Ashtabula, on the Periphytic Algae in the Sheyenne River, North Dakota

Abstract

AbstractThe Sheyenne River is a third order stream that drains a significant portion of central and eastern North Dakota. In 1950, the Baldhill Dam was built and as a result, the reservoir, Lake Ashtabula, was formed. The periphytic algae in this river were extensively studied from 1997 to 1999. During this research, the effects of differences in environmental variables on the algal communities were assessed with Canonical Correspondence Analysis (CCA). In this analysis, the periphytic algal communities in the downstream sites appeared to be quite different from those communities found upriver of Lake Ashtabula. Other research on different rivers has shown profound changes in the algal community after a dam was built along the river. Redundancy Analysis (RDA) was used to determine if the sites downstream are more statistically similar with Lake Ashtabula than with the upstream sites. Finally, CCA was used to examine which environmental variables explain the most variance in Lake Ashtabula and the downstream sites.