Evaluation of the Relationship between Stream Habitat Quality and Taxa and Trait Richness and Diversity in Piedmont Streams in North Carolina

Abstract

As impervious cover increases with urban development, stream channels are degraded by increased stormwater runoff, which negatively impacts stream habitat quality and benthic macroinvertebrate diversity. We examined the relationship between stream habitat diversity and aquatic insect taxa and trait richness and diversity at the watershed scale in 30 streams, covering a gradient of stream habitat quality. We then quantified the relationship between taxa and trait richness and diversity and seven microhabitats at the reach scale in ten streams with high habitat quality. We found that both taxa richness and diversity declined at a greater rate than trait richness and diversity along an in-stream habitat diversity gradient. Taxa richness was positively correlated with pools, runs, backwater, leaf packs, and riffles, while trait richness was positively correlated with runs, small wood, and riffles. Taxa diversity was positively correlated with pools and leaf packs while trait diversity was positively correlated with runs, leaf packs, small wood, and riffles. An indicator species analysis revealed that specific taxa and traits were associated with specific microhabitats or combinations of microhabitats. By correlating the taxa in urban streams with specific microhabitats, we can better evaluate the success of stream restoration in restoring stream function and in stimulating benthic macroinvertebrate recovery.

Ecology of Aquatic Invertebrates in Springs and Headwater Streams: Imperiled Habitats in a Changing World

“…This Special Issue provides a series of papers that advance our understanding of BMIs in headwater streams and springs, which will aid in elucidating ecological relationships, fine-tuning impact assessments, and promoting the conservation of these animals and their habitats. In this Special Issue, there are three papers related to spring ecosystems [1][2][3] and four papers related to small-discharge and headwater streams [4][5][6][7]. All of these papers deliver new and compelling findings, as well as useful tools and analyses that will aid future studies.…”

“…The final paper in this Special Issue studied the diversity of aquatic invertebrates across 30 streams on the watershed scale to assess the impacts of impervious cover [7]. Increasing impervious cover associated with urbanization has a negative impact on stream conditions and BMI diversity.…”