Ecological and chemical status of peri-urban lakes in the Ile-de-France region: data collection and indicator definition

International audiencePeri‐urban lakes provide essential economic, recreational and ecosystem services. They are subject to a large variety of local and global pressures that may interact, such as nutrient imbalance, organic micro-pollutants and trace metals from both agricultural and urban origins. In this context, one of the main objectives of the research project PULSE (Peri-Urban Lakes, Society, and Environment) was to investigate the impact of anthropogenic pressures on water quality of urban lakes by monitoring a large variety of physical, biological and chemical parameters on a representative sample of 49 lakes in the Ile-de-France region. The physical-chemical parameters (water, temperature, pH, conductivity and oxygen), the concentrations of biological parameters (Chlorophyll a, Cyanobacteria biomass, Escherichia coli densities…), and the chemical parameters (Polycyclic Aromatic Hydrocarbons and trace metals) were measured simultaneously in the water column during summer campaigns, performed during 3 successive years (2011, 2012, 2013). A comparative analysis of the values obtained on the lakes provides an interdisciplinary overview of the lake water quality indicators in Île-de-France region during 3 years. This analysis allows us to assess the links between biological and chemical status of the lakes and the characteristics of their catchment