FROM THE BENTHIC TO THE RIPARIAN: EFFECTS OF UNIONOID MUSSEL-DERIVED NUTRIENTS ON VASCULAR PLANTS AT THE AQUATIC-TERRESTRIAL INTERFACE
The loss of native freshwater mussels (Unionoida) from North American rivers threatens both biodiversity and freshwater ecosystem function. Mussels occur in dense multi-species aggregations, creating hotspots of biogeochemical activity. As filter feeders they consume organic particles containing nitrogen (N) and phosphorus (P) then release waste rich in bioavailable N and P. Mussel-derived nutrients enter various compartments of the food web, including the emergent vascular macrophyte Justicia americana. J. americana is widespread and commonly found in habitats where mussels occur. It is unknown if mussel-derived nutrient uptake alters J. americana stoichiometry or growth in a way that would benefit terrestrial herbivores which consume it, such as deer. We hypothesize that changes in availability of recycled N and P caused by manipulating the density of an experimental mussel community will affect J. americana stoichiometry (C:N:P ratios) and biomass accrual. We are testing this using stream mesocosms that model mussel communities found in nature. We predict the results will show that increased mussel density is associated with greater biomass accrual and decreased C:N:P in J. americana. These effects could reveal a previously unknown pathway by which aquatic resources subsidize terrestrial food webs.
Thomas Parr (Co-Presenter/Co-Author), University of Oklahoma, Thomas.firstname.lastname@example.org;
Caryn C. Vaughn (Co-Presenter/Co-Author), University of Oklahoma, email@example.com;
Jonathan Lopez (Primary Presenter/Author), University of Oklahoma, firstname.lastname@example.org;