Primary productivity drives temporal beta diversity of zooplankton communities in urban lakes

Abstract

Aim: The objective of this study was to evaluate the temporal beta diversity of zooplankton communities in urban lakes in two distinct seasonal periods and to associate this diversity with environmental variability and primary productivity. Methods: We sampled 14 urban lakes in Goiânia (Goiás state, Brazil) in February (rainy season) and September (dry season) 2023. Water samples were collected in each lake, to analyze phosphate and nitrogen nutrients. Furthermore, some limnological variables were obtained in the field. The zooplankton community was collected by filtering 200 liters of water through a 68 µm mesh and subsequent identification in the laboratory using a microscope. Results: We identified 110 taxa, with the greatest richness of rotifers and testate amoebae. The temporal beta diversity (TBI) varied between 0.46 and 0.78 and was not correlated with the temporal variability of the abiotic factors. On the other hand, TBI was negatively associated with mean chlorophyll-a concentration (proxy of primary productivity). Conclusions: In these urban lakes, high-productivity environments (e.g., eutrophic systems) promote biological homogeneity. We recommend that future studies incorporate additional variables to better understand environmental variability in urban lakes, as well as extend research over longer time scales.