Wetland Functional Area Division Method: A Correlation Analysis of Water Quality and Landscape Structure

The purpose of this study is to provide a clearer idea for the optimization of wetland functional areas and a new method for the identification and analysis of wetland functional areas under the background of the latest Wetland Protection Law in China. This study selected Pan’an Lake Wetland, the first national wetland park built in coal mining subsidence land in China, as the research object. By constructing a “Water-water-landscape-function” (WLF) model, combined with landscape pattern index and Nemerov pollution index method (NPI), the differences in water quality and landscape structure of different functional areas were analyzed. Then, Pearson’s Correlation Analysis and Redundancy Analysis are combined to quantitatively analyze the correlation between water quality environment and landscape structure. Finally, Inverse Distance Weighting (IDW) was introduced to help study the spatial difference in water quality in different functional areas. This study lasted for one year. Twelve water quality sampling points were set up, and 216 effective samples were collected monthly for one year. The results showed that: (1) the ratio of built-up land and cultivated land area had a high impact on water quality indicators in each water period, especially the increase in cultivated land patch density would increase the risk of TN and TP losing to surrounding water bodies; (2) the lakes and rivers in the wetland park have good ecological effects and should be widely used in various functional areas; (3) the degree of landscape fragmentation was negatively correlated with the overall water quality, while the degree of landscape agglomeration and landscape diversity were positively correlated with the overall water quality; (4) ecological corridors should be established between WCA and WRA, artificial corridors should be established between MEA and LEA, and ecological interception should be set between MEA and WRA; and (5) the “Water-quality-landscape-function” (WLF) model is an effective tool for the analysis and optimization of wetland functional areas, which provides a reference for the new round of wetland planning in China