Development of a zoning-based environmental–ecological coupled model for lakes: a case study of Baiyangdian Lake in northern China

Abstract. Environmental/ecological models are widely used for lake management as they provide a means to understand physical, chemical, and biological processes in highly complex ecosystems. Most research has focused on the development of environmental (water quality) and ecological models, separately. Limited studies were developed to couple the two models, and in these limited coupled models, a lake was regarded as a whole for analysis (i.e. considering the lake to be one well-mixed box), which is appropriate for small-scale lakes but is not sufficient to capture spatial variations within middle-scale or large-scale lakes. In response to this problem, this paper seeks to establish a zoning-based environmental–ecological coupled model for a lake. Hierarchical cluster analysis was adopted to determine the number of zones in a given lake based on hydrological, water quality, and ecological data analysis. The MIKE 21 model was used to construct 2-D hydrodynamics and water quality simulations. STELLA software was used to create a lake ecological model that can simulate the spatial variations of ecological condition based on flow field distribution results generated by MIKE 21. Baiyangdian Lake, the largest freshwater lake in northern China, was adopted as the study case. The results showed that the new model is promising for predicting spatial variations of ecological conditions in response to changes in lake water quantity and quality, and could be useful for lake management.