Seasonal and flow regime differences should be considered in explaining zooplankton metacommunity assembly

Abstract

Environmental and spatial filtering collectively regulate zooplankton communities, while their relative contributions to community structure may change with seasonal variations and flow regime differences. However, there is a lack of research on the combined effect of these two factors. To explore these differences, we studied zooplankton populations as well as environmental and geographical data from different seasons in rivers with variable flows in the Shaying River basin. According to our results, the assembly mechanisms for intermittent river (IR) communities fluctuated more and were more responsive to geographical factors than were the assembly mechanisms of perennial river (PR) communities during the wet and dry seasons. We discovered that the rotifer/protozoan assemblage was more vulnerable to spatial influences, whereas the composition of the crustacean group was heavily impacted by the environment. Our findings contribute to a better understanding of metacommunity assembly mechanisms in highly dynamic ecosystems.