Forested Riparian Buffers Change the Taxonomic and Functional Composition of Stream Invertebrate Communities in Agricultural Catchments

Abstract

Riparian zones form the interface between stream and terrestrial ecosystems and play a key role through their vegetation structure in determining stream biodiversity, ecosystem functioning and regulating human impacts, such as warming, nutrient enrichment and sedimentation. We assessed how differing riparian vegetation types influence the structural and functional composition (based on species traits) of stream invertebrate communities in agricultural catchments. We characterized riparian and stream habitat conditions and sampled stream invertebrate communities in 10 independent site pairs, each comprising one “unbuffered” reach lacking woody riparian vegetation and a second downstream reach with a woody riparian buffer. Forested riparian buffers were associated with greater shading, increased gravel content in stream substrates and faster flow velocities. We detected changes in invertebrate taxonomic composition in response to buffer presence, with an increase in sensitive Ephemeroptera, Plecoptera and Trichoptera (EPT) taxa and increases in key invertebrate species traits, including species with preference for gravel substrates and aerial active dispersal as adults. Riparian vegetation independently explained most variation in taxa composition, whereas riparian and instream habitat together explained most variation in functional composition. Our results highlight how changes in stream invertebrate trait distributions may indirectly reflect differences in riparian habitat, with implications for stream health and cross-ecosystem connectivity.

Temporal changes in headwater streams macroinvertebrate assemblages during the snowmelt season in northeast china

“…Frontiers in Environmental Science frontiersin.org of litter residue and sediment on both sides quickly enters the stream channel during ice and snow melt (Brighenti et al, 2019). Although this process increases the turbidity of stream water, it also simultaneously transports a large amount of organic matter into the stream (Brighenti et al, 2019;Sargac et al, 2021). Climate change in the surrounding environment can affect the environmental characteristics of stream ecosystems (Brown et al, 2018;Brighenti et al, 2019), which has a significant impact on stream hydrology and water quality in particular (Lencioni et al, 2021).…”

Regression Tree Analysis for Stream Biological Indicators Considering Spatial Autocorrelation

“…Additionally, previous studies reported that riparian forests adjacent to streams directly influence the flow mechanisms of sediments, organic matter, and nutrients from watersheds [19,20]. Riparian forests have various functions, such as preventing bank erosion, reducing organic matter and nutrients, controlling water temperature, providing habitats for aquatic and terrestrial organisms, increasing ecological health and diversity, and mitigating the negative effects of land use on rivers [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Therefore, the relationships between land cover (particularly, green and urban areas) and stream conditions need to be studied in detail to develop programs for improving the stream health and implementing stream restoration and management strategies [34].…”