Effects of Stream Crossings on Macroinvertebrate Assemblages of the Upper Current River, Ozark National Scenic Riverways, Missouri

This study examined the impact of road crossings on benthic macroinvertebrate communities in a wadeable Ozark river. I collected macroinvertebrates during winter and summer from four riffle locations (upstream, at crossing, downstream, and farther downstream) at each of five sites in the upper Current River (mean discharge 12 m3 s-1). Sixteen environmental variables were measured at each location to characterize sites. Using digital photographs from trail cameras, traffic frequencies were calculated and largely consisted of hikers and horses. Based on counts of 68,353 individuals from 111 macroinvertebrate taxa, I calculated four metrics (taxa richness, Shannon's index, EPT, biotic index) combined into the Stream Condition Index and assessed effects of stream crossings with a two-way nested ANOVA for each season. All metrics showed strong differences among sites but inconsistent effects among locations. Multivariate analyses (NMDS and a nested ANOSIM) also revealed strong differences in community composition among sites, as well as among locations. Taken together, the results indicate crossing disturbances during summer and winter 2009 were either too infrequent or small in intensity to impair benthic macroinvertebrate communities.

Name thesis:degree_name

Master of Science in Biology

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Biology

Year

2010

Author dc:creator

• Heth, Rachel Lee Sine

Contributors dc:contributor

• John Havel

• benthic community
• traffic
• Stream Condition index
• taxa richness
• EPT richness
• biotic index
• Shannon's Diversity Index
• Biology

Statement dc:rights

• © Rachel Lee Sine Heth

Repository record dc:identifier

https://bearworks.missouristate.edu/theses/1276

OAI identifier oai:identifier

oai:bearworks.missouristate.edu:theses-2277