Trait-based insights into arthropod community shifts following forest disturbance

Emerald ash borer (EAB; Agrilus planipennis) is an invasive buprestid beetle that has recently established in northern Minnesota and will cause widespread mortality of black ash (Fraxinus nigra), the dominant tree species in the forested wetlands that cover approximately 1.2 million acres across Minnesota. Black ash wetlands are a unique ecosystem that provides many ecological services, including water table regulation, carbon sequestration, and supporting many taxa. As EAB eliminates populations of black ash, these forests are expected to transition into sedge and shrub-dominated wetlands. Landscape-level shifts trigger cascading ecological effects, including changes in arthropod community structure and the ecosystem services they support. Here, we assess arthropod community structure and ecological function across a simulated disturbance gradient representing forest alteration due to EAB. Arthropod communities were assessed across three treatments: undisturbed black ash stands, experimental plots where all black ash trees were girdled, and plots where all black ash were pre-emptively harvested. Utilizing functional traits allows us to link shifts in arthropod community structure to ecosystem processes. Using next-generation sequencing, we characterized community assemblages and evaluated shifts in taxonomic and functional trait composition. We hypothesize that disturbance will alter arthropod functional diversity and trait distributions, which in turn influence ecosystem processes. As black ash forests undergo structural change, cascading effects will alter community function. To evaluate these shifts, we used a Fourth Corner analysis to link environmental gradients to species traits and assess how disturbance alters functional composition. Understanding these changes will help us predict arthropod response to landscape-level disturbance.