Utilization of riverine organic matter by macrobenthic communities in a temperate prodelta

Macrobenthos is an important component of organic carbon storage and energy flow in marine systems, including these impacted by riverine discharge high share allochthonous matter (OM). Changing environmental conditions, such as lower precipitation snow cover duration, may affect patterns input, therefore it crucial to know how benthic communities utilize different OM sources areas affected rivers. Using Bayesian stable isotope mixing models, we assessed the diet composition common macroinvertebrates forming transition zone one largest river outlets Baltic Sea region, Vistula River prodelta. Furthermore, analyzed spatial temporal variability biomass-weighted resource utilization those communities. Contribution particulate prodelta decreased with increasing depth. Despite similar distances mouth, relative contribution all studied taxa also depth, which corresponded waters. Nevertheless, due synchronous structural changes communities, feeding modes dominant species, particularly Macoma balthica Hediste diversicolor , biomass often remained highest deepest parts. Our study corroborates that primary consumers act a gateway for into food web illustrates sediment properties partitioning affects structure their abilities OM.