Aquatic Insect Community Functional Responses to Canopy Cover Changes Along Gradients of Elevation a
Parameters: Chlorophyll, Algal Classification
Congratulations to Carolina Gutierrez who was awarded a Travel Stipend for his presentation at the ESA 2019 featuring our AquaFluor Handheld Fluorometer and PhytoFind in situ Algal Classification Instrument.
Growing levels of human-induced changes on mountainous streams around the globe demand for an understanding of how species diversity and ecosystem function are affected by increasing water temperature and loss of riparian coverage along environmental gradients. Organismal traits determine how species perform and contribute to ecosystem functioning. Functional diversity quantifies the value and range of these traits, which provides a mechanistic framework to understand community productivity and resilience to perturbations or invasion. We applied a multifaceted framework to quantify functional diversity of stream insects along gradients of canopy coverage, water temperature and elevation across the Rocky Mountain Streams of Colorado. We quantified three primary components of functional diversity of stream insects along environmental gradients of canopy coverage, water temperature and elevation across the Rocky Mountain Streams of Colorado. We performed multivariate analyses (principal component and NMDS) to understand how changes in the species diversity of aquatic insect assemblages translate into changes of functional diversity along gradients of canopy coverage, water temperature and elevation across 26 headwater streams in the Rocky Mountains of Colorado. Results/Conclusions Our results based on analyses on a matrix of 21 traits per taxon collected, showed a strong relationship between species and functional diversity independent of the functional traits used, with no evidence for saturation in this relationship. Traits related to voltinism (number of generations per year), development, ecological habit, and adult dispersal ability, showed the highest correlation to changes in the environment; particularly to water temperature changes over 1°C in areas with open canopy (less than 60% coverage). These findings support the understanding that small tributary streams collectively exhibit high beta diversity; and that taxonomic (as well as functional) richness of aquatic insects declines with elevation in headwater mountain streams. Habitat heterogeneity and changes in water temperature along the elevational gradient, coupled with increased pressure on dispersal traits between isolated communities, contributes to sustaining large biotic heterogeneity among small montane streams. Observed results regarding changes in taxonomic and functional diversity along canopy coverage gradients have important implications for understanding the impact of riparian cover loss on aquatic insect communities and stream ecosystem function. >>View Presentation
Author: Carolina Gutierrez, Rachel Harrington, Boris Kondratieff, Colleen Webb, Cameron Ghalambor and N. LeRoy Poff
Institution: Colorado State University, Colorado, USA