Healthy plankton communities are the foundation of many freshwater food webs. Their biodiversity is often used to directly reflect the health of the rivers. Globally, river ecosystem restoration is a critical issue and many freshwater ecosystems, especially in cities, are degraded because of intensive human activities. This is true for Jinan, China’s first pilot city for the Water Ecological Civilisation Project. The outcomes of aquatic ecosystem restoration in the city will directly affect the success or failure of the construction of aquatic ecological civilisations across the entire country; therefore, there is an urgent need for research on the assessment of river health in Jinan based on plankton biodiversity. As such, this study gathered data on the distribution of plankton (phytoplankton and zooplankton) in Jinan by collecting three sets of samples from 59 aquatic ecosystem monitoring stations in spring, summer and autumn of 2015. In all, 104 species of phytoplankton and 56 species of zooplankton were identified. Diatoms, Chlorophyta, and Cyanophyta accounted for 50, 31 and 15% respectively of phytoplankton, and rotifers, Protozoa and cladocerans accounted for 39, 31 and 17% respectively of zooplankton. We constructed a plankton health assessment model based on the Shannon–Wiener diversity index for analysis of the temporal and spatial distribution. According to the overall health distribution diagram, spatially health status was significantly better in north and south Jinan than in the city centre; temporally, spring water ecosystem health was better than in summer and autumn. These conclusions provide a theoretical basis and direction for the restoration of aquatic ecosystems in Jinan, and the methods used in this study can serve as a reference for aquatic ecosystem evaluation in developing countries.
The role of biomarkers in the assessment of aquatic ecosystem health
