An assessment of macroinvertebrate functional feeding groups upstream and downstream of dam on Sharon Creek.
Start Date
April 2024
Location
2nd floor - Library
Abstract
Dams negatively impact aquatic ecosystems by altering stream flow, sedimentation, nutrient levels and habitat critical for biota. The overall objective of this study was to assess local dam impacts on aquatic ecosystems. Macroinvertebrates are aquatic biota often used as biological indicators of ecosystem health because they respond to multiple environmental stressors. The specific objective of this study was to assess stream macroinvertebrate community function above and below a dam. This study will also provide baseline data to assess future dredging impacts planned in this watershed. This study was conducted in Sharon Creek, Cincinnati, Ohio with samples collected in September 2023. Three sites were chosen within Sharon Creek, one site located upstream, and two sites located downstream of the dam and reservoir. Benthic riffle samples (n=5) were collected using a Surber sampler and a timed-search and a composite sample (n=1) was collected from all habitats within a designated reach at each site. Macroinvertebrates were identified to the family level using a dissecting microscope. Downstream sites had more functional diversity and were dominated with scrapers, whereas upstream had less functional diversity and was dominated by filtering and gathering-collectors. Using functional feeding ratios, both downstream sites were autotrophic, while upstream was heterotrophic. The most downstream site had significantly greater photosynthesis/respiration (ANOVA, F=17.86, DF= 2,12, p<0.001) and channel stability (ANOVA, F= 36.06, DF=2,12, p<0.001) compared to other sites. All three sites appear impacted by the dam within and surrounding habitat modifications. This study will provide valuable baseline data for future assessments.
An assessment of macroinvertebrate functional feeding groups upstream and downstream of dam on Sharon Creek.
2nd floor - Library
Dams negatively impact aquatic ecosystems by altering stream flow, sedimentation, nutrient levels and habitat critical for biota. The overall objective of this study was to assess local dam impacts on aquatic ecosystems. Macroinvertebrates are aquatic biota often used as biological indicators of ecosystem health because they respond to multiple environmental stressors. The specific objective of this study was to assess stream macroinvertebrate community function above and below a dam. This study will also provide baseline data to assess future dredging impacts planned in this watershed. This study was conducted in Sharon Creek, Cincinnati, Ohio with samples collected in September 2023. Three sites were chosen within Sharon Creek, one site located upstream, and two sites located downstream of the dam and reservoir. Benthic riffle samples (n=5) were collected using a Surber sampler and a timed-search and a composite sample (n=1) was collected from all habitats within a designated reach at each site. Macroinvertebrates were identified to the family level using a dissecting microscope. Downstream sites had more functional diversity and were dominated with scrapers, whereas upstream had less functional diversity and was dominated by filtering and gathering-collectors. Using functional feeding ratios, both downstream sites were autotrophic, while upstream was heterotrophic. The most downstream site had significantly greater photosynthesis/respiration (ANOVA, F=17.86, DF= 2,12, p<0.001) and channel stability (ANOVA, F= 36.06, DF=2,12, p<0.001) compared to other sites. All three sites appear impacted by the dam within and surrounding habitat modifications. This study will provide valuable baseline data for future assessments.