Oral Presentation Freshwater Sciences 2023

How are stream macroinvertebrates responding to variations in landuse and remediation levels? (#282)

Sergio A Sabat-Bonilla 1 , Marlaina Marvin 1 , Kelly O Maloney 2 , Greg Noe 3 , Sally Entrekin 1
  1. Entomology Department, Virginia Tech, Blacksburg, VA, USA
  2. Leetown Science Center, U.S. Geological Survey's (USGS), Kearneysville, WV, USA
  3. Florence Bascom Geoscience Center, U.S. Geological Survey's (USGS), Reston, VA, USA

Rapid global change continues to impact both past and present anthropogenic and environmental stressors on freshwater ecosystem functions and biodiversity in streams. Since aquatic macroinvertebrates provide key ecosystem services and functions, they are ideal indicators of local and ecosystem-wide responses to anthropogenic stressors. For this reason, their community structure is commonly assessed by studying their response to stressors and the subsequent remediation practices (e.g., best management practices). Yet, focusing on the taxonomic identity of macroinvertebrate communities may fail to inform the selection pressures driving biological responses. Integrating functional trait diversity into established assessment protocols allows for expanded quantification of biological responses to remediation efforts to reach biological uplift. However, a needed first step is to understand what types of traits show the greatest affinity to environmental changes. The objective of this study is to refine regional stream assessment protocols for the Chesapeake Bay Watershed, one of the most well-studied freshwater ecosystems in the world. We will assess a) the influence of single-trait selection when multiple traits (e.g., filter-feeder and collector-gatherer) have been assigned to a grouping feature (e.g., FFG) for the same aquatic macroinvertebrate taxa, and b) quantify how functional trait diversity responds across varying pasture landuse gradients with different remediation levels. We hypothesize that functional traits weighted by biomass will explain more variation across the landuse and remediation gradients because they better represent the biological response to these stressors compared to taxonomic diversity metrics alone. Preliminary results suggest that functional diversity metrics like evenness, richness and quadratic entropy (Q) better represent the aquatic macroinvertebrate responses along the landuse and remediation gradients than taxonomic diversity metrics alone.

  1. Noe, G. B., Cashman, M. J., Skalak, K., Gellis, A., Hopkins, K. G., Moyer, D., ... & Hupp, C. (2020). Sediment dynamics and implications for management: State of the science from longā€term research in the Chesapeake Bay watershed, USA. Wiley Interdisciplinary Reviews: Water, 7(4), e1454.
  2. Poff, N. L., Olden, J. D., Vieira, N. K. M., Finn, D. S., Simmons, M. P., & Kondratieff, B. C. (2006). Functional trait niches of North American lotic insects: traits-based ecological applications in light of phylogenetic relationships. Am. Benthol. Soc, 25 (4).