Kaize Zhang

Based on the symbiosis theory, the concept of compatibility within the regional water-energy-food-ecology (WEFE) system was proposed. An indicator system for adaptability analysis was constructed from three subsystems: coordination, stability, and sustainability. Using the co-evolution model and partial autocorrelation analysis, the spatiotemporal evolutionary patterns and spatial correlation patterns of WEFE adaptability in the Yellow River Basin (YRB) from 2011 to 2022 were assessed. The results indicated that: (1) The order of subsystem weights was: stability > sustainability > coordination. (2) The absolute adaptability of the indicator was significantly higher than the relative adaptability. The adaptability degree of the three subsystems increased to varying degrees. Overall, the adaptability of the WEFE system in the middle and lower reaches of the YRB was obviously higher than in the upper reaches. (3) In terms of system coordination, the coordination and stability subsystems improved, whereas the coordination of the sustainability subsystem gradually declined. (4) The adaptability levels of the WEFE system in the YRB had a random distribution. In terms of local spatial autocorrelation, there were significant spatial disparities and path dependencies in the WEFE system adaptability across the YRB. This study enhances the understanding of the symbiotic adaptability development among water resources, food, energy and ecology in the YRB and provides important insights for regional multi-resource collaborative management.

The corporate water use audit system is an important part of implementing China’s strictest water resource management system and building a water-saving society. Since 2009, seven provinces (municipalities/autonomous regions) in China have begun to explore corporate water audits. However, conflicts of interest between the Chinese government, water-using enterprises, and commissioned third-party auditors may lead to the ineffective promotion of the corporate water audit policy. In this paper, we study corporate water auditing behavior from the perspective of information asymmetry, construct an evolutionary game model of the three parties, explore the strategy choices of each party, study the asymptotic stability of the evolutionary stability problem via numerical methods, and analyze the impact of parameter changes on it. The study shows that, firstly, strict governmental supervision plays a key role in promoting the implementation of corporate water audit systems. Incentive subsidies had a positive and direct impact on firms and auditors in the water audit system. Secondly, the higher rent-seeking costs of tripartite audit institutions affect the probability of firms’ participation in rent-seeking. As a social institution, regulation and penalties for firms should be strengthened to reduce the risk of information asymmetry. The results of this study provide insights into the existence of asymmetry problems and possible coping strategies.

Accounting for water resources assets is an important part of the inventory of nationally owned natural resources assets, and is a basic prerequisite for the preparation of natural resources balance sheets. This study examines the macroeconomic data of the 11 provincial-level regions in the Yangtze River Economic Belt (YREB) from 2012 to 2021. It begins by elucidating the natural system of water resources formation and the economic system of water resources asset formation. The concept of potential water resources assets is introduced, and the cyclical patterns of water resources asset evolution are investigated. Then, based on the "quantity-value" framework, the adjusted coefficient method and energy value analysis method are adopted to construct models for the physical quantity and value accounting of regional water resources assets. Finally, an indicator system is designed from economic, social, environmental, and ecological dimensions. The geographic detector model is selected to explore the influencing factors of spatial differentiation of water resources assets. The research findings reveal that: (1) The physical volume of water resources assets in the YREB demonstrates fluctuating changes, reaching a peak of 2734.27 billion m3 in 2019 and a low value of 2548.70 billion m3 in 2020. Specifically, Shanghai, Jiangsu, Hunan, and Yunnan display "N"-shaped trends, while Jiangxi, Hubei, and Guizhou demonstrate "W"-shaped trends. The remaining regions exhibit more moderate trends. (2) The overall value of water resources assets fluctuates, showing an upward trend with an average annual increase of 13.14%. The spatial distribution of water resources asset value exhibits a pattern of "downstream>midstream>upstream" differentiation. (3) Population density is identified as the primary driver of spatial differentiation in water resources assets within the YREB. The cumulative explanatory power of the social subsystem is the highest, indicating that social factors have the greatest influence on the spatial pattern of water resources assets. The research findings contribute to elucidating the cyclic evolution process of water resources, latent water assets, and water resources assets, improving the macroeconomic accounting system, and providing valuable insights for the sustainable utilization of water resources.

During the flood season, various regions in a watershed often have flood drainage conflicts, when the regions compete for flood drainage rights (FDR). In order to solve this problem, it is very necessary to study the allocation of FDR among various regions in the watershed. Firstly, this paper takes fairness, efficiency and sustainable development as the allocation principles, and comprehensively considers the differences of natural factors, social development factors, economic development factors and ecological environment factors in various regions. Then, an indicator system for allocation of FDR among regions in the watershed is established. Secondly, an entropy weight Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) model is used to construct the FDR allocation model among regions in the watershed. Based on a harmony evaluation model, a harmony evaluation and comparison are carried out on the FDR allocation schemes under three different allocation principles. Finally, taking the Jiangsu section of the Huaihe River watershed as an example, the FDR of eight cities in the watershed are allocated and evaluated to see if the allocation scheme is harmonious. The results show that the allocation scheme of FDR based on the principles of fairness, efficiency and sustainable development has the highest degree of harmony, which can meet the FDR demands in various regions in the watershed, avoid the occurrence of flood drainage conflicts among regions, form an orderly flood drainage situation and promote the harmonious development of the watershed.

As the key source for freshwater resources, urban rivers are essential for human survival and urban socio-economic development. Recently, the functions of urban rivers have been damaged by increasing human activities. A better understanding of the health state of urban rivers is the basis of sustainable urban planning. To this purpose, this research took the Jinshui River as a research area. An indicator system for urban river health evaluation was first established using the driving force-pressure-stateimpact- response (DPSIR) framework. The health state of the Jinshui from 2008 to 2017 was then assessed based on the urban river health index, which was calculated by the improved fuzzy matterelement extension model. The results show that the overall health status of the Jinshui has improved, from its unhealthy state in 2008-2016 to a sub-healthy state in 2017. Corresponding response measures have achieved certain results, which have led to an improvement in the health state of the river. However, its health still faced many problems, including pressure from a rapid urbanization rate and population density, a large amount of sewage discharge, and serious water pollution. In general, the health of the Jinshui was still on the low side. Therefore, to ensure sustainable water environment in the region, it is necessary to further govern the water environment and improve the health status of urban rivers. This research can help government easily understand an urban river’s health state and formulate effective measures in the future.

Water resource security is an important condition for socio-economic development. Recently, the process of urbanization brings increasing pressures on water resources. Thus, a good understanding of harmonious development of urbanization and water resource security (WRS) systems is necessary. This paper examined the coordination state between urbanization and WRS and its obstacle factors in Beijing city, utilizing the improved coupling coordination degree (ICCD) model, obstacle degree model, and indicator data from 2008 to 2017. Results indicated that: (1) The coupling coordination degree between WRS and urbanization displayed an overall upward tendency during the 2008–2017 period; the coupling coordination state has changed from an imbalanced state into a good coordination state, experiencing from a high-speed development stage (2008–2010), through a steady growth stage (2010–2014), towards a low-speed growth (2014–2017). (2) In urbanization system, both the social and spatial urbanizations have the greatest obstruction to the development of urbanization-WRS system. The subsystems of pressure and state are the domain obstacle subsystems in WRS system. These results can provide important support for urban planning and water resource protection in the future, and hold great significance for urban sustainable development.