Urban lake spatial openness and relationship with neighboring land prices: Exploratory geovisual analytics for essential policy insights

Possessing ecological service functions, as well as social and economic values, urban lakes are an important part of urban open spaces. The improvement in the openness of urban lakes is crucial to enhancing the efficiency and fairness of urban land use. Accompanied by China's rapid urbanization, China's urban land prices continue to rise and the government relies on land finance. Meanwhile, the number of urban lakes is decreasing, the lake water surface area is shrinking, and water pollution is becoming more serious. By using exploratory indicators, this study quantifies the degree of openness of urban lakes, and focuses on the relationship between lake spatial openness and neighboring land prices. Taking Wuhan (China) as a study case, we proposed a conceptual framework to guide the analysis within the context of land use policy. Then, we created exploratory indicators to quantify the spatial openness of urban lakes and mapped the results. Afterward, we conducted an exploratory geovisual analytics of urban land prices and lake spatial openness. Finally, we used a regression model to examine the relationship between prices and openness. Our results show that our new indicators were able to reflect the openness of the lakes in the central urban area of Wuhan simply and effectively. The overall spatial openness is relatively high, the mean values of two main indicators reflecting the openness percentage of the lakes are 69.91 % and 67.57 % respectively. However, there are still obvious regional differences between the openness indicators. The relationship between openness and neighboring land prices is spatially heterogeneous. Based on our analysis, we finally propose policy suggestions for protecting urban lakes and rational land use in the rapid urban expansion occurring in developing countries.