PS 37-25 - Benthic macroinvertebrate assemblages across the intermittent stream system of the Konza Prairie, Kansas

Abstract: Non-perennial streams and rivers, those that dry or cease to flow, comprise the majority of earth’s waterways. As drying increases due to climate change, research into how drying influences spatial variation among communities is vital. Using a local contribution to beta diversity (LCBD) approach, we investigate local environmental factors that influence benthic macroinvertebrate meta-community structure: distance to perennial groundwater sources, canopy cover, substrate composition, and dissolved oxygen. We used DNA metabarcoding methods to quantify benthic macroinvertebrates at 42 of 50 total sites across the South Fork of Kings Creek in the Konza Prairie Biological Station (Kansas, USA). We predict that sites with less canopy cover will have longer dry periods due to increased evaporation, leading to assemblages that consist primarily of resistant taxa such as Chironomidae. Conversely, sites with more canopy cover will be more diverse and have a greater proportion of taxa belonging to the ‘shredder’ functional feeding group due to the increase in terrestrial leaf litter that they consume.  Finally, we predict that upstream and continuously flowing sites will influence LCBD, serving as source populations of colonists to non-perennial sites when water flow resumes and connects the system. This study will expand our current knowledge of how benthic macroinvertebrate communities are structured within a non-perennial stream, and can be used in the future to better inform management and policy to protect and preserve these communities and the environment they rely on.