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

Abstract

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 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 was appropriate for small-scale lakes and was 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. The hierarchical cluster analysis (HCA) was adopted to determine the number of zones for a lake based on the analysis of hydrological, water quality and ecological data. MIKE21 model was used to construct two-dimensional hydrodynamics and water quality simulations. STELLA software was used to create a lake ecological model which can simulate the spatial variations of ecological condition based on flow field distribution results generated by MIKE21. The Baiyangdian Lake, the largest freshwater lake in Northern China, was adopted as the study case. The results showed that the new model was promising to predict the spatial variation trends of ecological condition in response to the changes of water quantity and water quality for lakes, and could provide a great convenience for lake management.