Regional Ecological Risk Assessment with Respect to Human Disturbance in the Poyang Lake Region (PYLR) Using Production-Living-Ecology Analysis

In the regional ecological risk assessment (RERA) research with respect to human disturbance, risk source-receptor identification and corresponding indicators selection are of great importance. In this study, three regional function indexes, i.e., production function index, living function index, and ecology function index, were produced and incorporated into the human-caused RERA research. Among them, the former two indexes can be considered as human disturbance indexes, namely risk source indexes, whereas the last one can be deemed as ecological risk receptor index. Based on related economic statistics and land-use data, which are commonly used approaches for data acquisition, these three spatial function indicators were calculated separately. Incorporated with eco-environmental vulnerability proxies, this RERA framework was realized finally. With the Poyang Lake Region as a case study, the proposed RERA model was practiced to examine its effectiveness in expressing and revealing spatial heterogeneities of regional ecological risk source, risk receptor, eco-environmental vulnerability, and final integrated risk level. The results showed that: (1) the main winter waterbody of Poyang Lake was mainly in the grade of medium risk (grade 2), whereas the north connection part between the lake and the Yangtze River, and the south semi-closed sub-lakes, such as the Junshan Lake, were in high-risk group (grade 3); (2) the west part of the region had a higher human-caused risk level on the whole than that of the east, especially those in Jiujiang and Nanchang cities, in accordance with higher production and living human-disturbance level there; (3) owing to near to the downtown of cities, the wetlands and forestlands within the scope of Nanchang and Jiujiang cities, such as Nanjishan Wetland National Nature Reserve in Nanchang City and Lushan Mountain Forest in Jiujiang City, all had high final risk level (grade 3); (4) in terms of proportion, the low-, medium-, high-, and very-high-risk grades accounted for 47.27%, 33.01%, 13.56%, and 6.16% of the region, respectively. The three regional function indexes adopted in this study, characterizing spatial heterogeneity of regional ecological risk with respect to human activities, will be helpful for related research in the future. Besides, the assessment results could provide scientific basis for regional ecological risk management and then sustainable development of the study area.