Assessing the Effects of Phytoplankton Structure on Zooplankton Communities in Different Types of Urban Lakes

Abstract

Urban lakes play important roles in microclimate regulation such as controlling run-off and groundwater recharge, as well as being a source of water supply and a habitat for a wide variety of flora and fauna. Bucharest has a wide variety of water resources where phytoplankton represent the dominant primary producer, the defining biological factor for zooplankton development. Our hypothesis was that as a result of anthropogenic pressures, phytoplankton in the urban aquatic ecosystems diminish the qualitative and quantitative capacity to maintain a good health condition with effects on the food web. By the structural features of the phytoplankton and zooplankton communities, the objectives were to determine the changes in diversity in different types of urban lakes, to explore the relationships between communities, and to determine the response of phytoplankton and zooplankton functional groups to the environmental factors. The ecological status assessed by Chlorophyll-a (µL−1) highlights that most of the investigated lakes were eutrophic and hypereutrophic. The phytoplankton were influenced by lake types, seasonal variations and nutrient input. The dominance of the Chlorophyceae, Cyanobacteria and Bacillariophyceae influenced the zooplankton’s development. The rotifers were the most represented in both species richness and abundance in zooplankton, followed by Copepoda young stages.