Ecological security evaluation and early warning in the water source area of the Middle Route of South-to-North Water Diversion Project.

Ecological security has important influence on regional sustainable development. The ecological security of Nanyang, the water source area of the Middle Route of South-to-North Water Diversion Project, was threatened because of surface water pollution. The existing studies had not been able to comprehensively assess the ecological security and future trend of water source area. In order to promote the high-quality development of the follow-up projects of the South-to-North Water Diversion project, it is very important to probe into the current situation and predict the future trend of ecological security in the water source area. Therefore, this paper constructed an ecological security evaluation index system based on the Driving force, Pressure, State, Impact and Response (DPSIR) model, used the combination of Analytic Hierarchy Process and- entropy weighting method to evaluate the ecological security of each district and county in Nanyang from 2000 to 2020, and used the auto regressive integrated moving average (ARIMA) model to predict the ecological security of the water source area from 2021 to 2030. The results demonstrated that: (1) The ecological security of Nanyang had changed from a moderate warning to a general safety, and the ecological security index had improved. The ecological security level of Nanyang would improve continuously from 2021 to 2030. (2) The northwest area and the central area of Nanyang had better ecological security states, while the southeast area wasn't so. Based on the results, the countermeasures for improving ecological security were proposed.

Impact assessment on the economy, society, resource, and environment in the water-receiving cities of the Middle Route Project of South-to-North Water Diversion.

The Middle Route Project of South-to-North Water Diversion (MRPSNWD) is a major strategic project to alleviate the serious shortage of water resources in northern China, and it benefited 14 large- and medium-sized cities in Henan, Hebei, Beijing, and Tianjin. Most of the predecessors used qualitative analysis to study the impact of the MRPSNWD on the water-receiving cities (WRCs), and they only considered one aspect of economy, society, resources, and environment, which could not fully reflect the impact of the MRPSNWD on the water-receiving cities. Therefore, based on the data of economic and social resources and environment of the water-receiving cities in the MRPSNWD from 2010 to 2019, an evaluation model based on entropy weight-analytic hierarchy process (AHP) fuzzy comprehensive evaluation method was constructed to account for the impacts on the economy-society-resources-environment of the water-receiving cities after the operation of the MRPSNWD and scientifically evaluated the comprehensive benefits of the MRPSNWD. The evaluation results revealed that the economic and environmental impacts of the MRPSNWD on the water-receiving cities were more obvious than those on society and resources. As far as water-receiving cities were concerned, the impact of the Middle Route Project of South-to-North Water Diversion on Zhengzhou, Shijiazhuang, Tianjin, and Beijing was generally higher than that of other cities. As far as the Middle Route Project of South-to-North Water Diversion was concerned, its overall impact on water-receiving cities was relatively slow.