This study investigates the ecological impact of restoration flows and scouring events on benthic macroinvertebrate (BMI) communities within the Trinity River, an ecosystem historically impacted by anthropogenic activities. Central to this study is the examination of how hydrologic alterations, especially the construction of the Lewiston Dam, have influenced these vital ecological indicators. Using data collected earlier in 2023 from a current study by Benjamin King, we analyzed BMI samples from three river sites (Junction City, Pear Tree, and Lorenz Gulch), both prior to and following a major scouring event in January 2023. This paper utilizes statistical analyses, including ANOVA and t-tests, to assess changes in BMI biomass and species diversity. Notably, the results demonstrate a significant reduction in BMI biomass post-scour, with a significant shift in the community composition towards species more beneficial as salmonid prey. These findings highlight the ecological shifts occurring in response to managed river restoration efforts and stress the importance of considering BMI dynamics in river restoration management. This study contributes valuable insights into riverine ecosystem responses to environmental management strategies, offering an understanding of the impacts on aquatic biodiversity.


Fall 2023


Environmental Science & Management


Ecological Restoration


Daniel Lipe

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