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Developing an efficient strategy for managing nutrients in less-developed lake watersheds that can balance the need for socioeconomic progress with the protection of aquatic ecosystems has become an urgent research subject for achieving sustainable development. This paper improves the optimization method for environmental and economic management of lake watersheds proposed in our previous research. A spatiotemporal optimization method based on a coupling model consisting of the Soil and Water Assessment Tool, system dynamics model, and objective programming model was applied to an agricultural non-point source (ANPS) pollution control program and a rural sewage treatment program at the Yilong Lake watershed as a case study. A simulation evaluation showed that the efficiency of the previous scheme was significantly improved after conducting spatiotemporal optimization. This scheme was dynamic and distributed, demonstrating an annual and high-resolution control program that can provide a basis for the precise management of ANPS. Although it still requires improvement, a framework for coupling simulation and two-step optimization was achieved in this study. • A framework for coupling simulation and two-step optimization is completed. • Spatiotemporal optimization could significantly improve the scheme, which is output by an objective programming model. • A dynamic and high-resolution NPS control program for paddy fields is obtained. [ABSTRACT FROM AUTHOR]

The environmental effects of the urban agglomeration planning policy (UAPP) are an exploration by rapidly developing China and a concern for countries seeking development and urban reform around the world. This paper takes the three regional urban agglomerations in the Yellow River Basin (YRB) as the research object and collects the panel data of 106 prefecture-level cities from 2006 to 2019 to study the reduction effects of UAPP on the industrial wastewater discharge (IWD). The empirical results from Difference-in-Differences models indicate that UAPP can significantly inhibit IWD. UAPP reduces IWD by promoting green innovation, and the development of service industries can strengthen this effect. UAPP shows a stronger IWD reduction effect in the northeast YRB than that in the southwest region. Compared to urban agglomerations with a single provincial jurisdiction, UAPP exerts stronger IWD reduction effects on urban agglomerations with multiple jurisdictions. Moreover, there exist spatial spillover effects of UAPP on IWD. These findings provide support and references for urban reform and the development of green cities in countries around the world, especially in developing countries. • Urban agglomeration planning policies can reduce industrial wastewater discharge. • Green innovation is the main intermediary factor. • Service industry development strengthens the discharge reduction effects. • The discharge reduction effects are stronger with multiple jurisdictions. • There exist spatial spillover effects of the discharge reduction effects. [ABSTRACT FROM AUTHOR]

Due to insufficient understanding of human-water interaction, many water-related problems arise in watersheds, posing severe threats to the sustainability of watershed development. Although water environmental carrying capacity (WECC) is a powerful tool to support sustainable development of watersheds, few studies considered aquatic ecological factors and uncertainty in indicator values, leading to losses of sample information in the evaluation of WECC. This paper developed a systematic framework for comprehensive WECC assessment that included the indicator system and a novel variable fuzzy pattern recognition (VFPR) approach. The WECC index system incorporated aquatic ecological factors, and addressed uncertainties associated with the indicator values. The proposed VFPR-based assessment model could realize successive evaluation to retain more original information of the sample and distinguish similar result values by treating the sample as having a continuous degree of membership instead of the traditional point form. In addition, it could be more adaptable to various circumstances including extreme cases, and closely reflect the impacts of indicator changes on the results. The established evaluation framework has been applied to Dongjiang River Basin in Guangdong Province. The spatial differences and main influencing factors of WECC in the study area were analyzed. Results show that 50% and 16.7% of the sub-regions in the study area would be subject to a poor level of WECC under pessimistic and optimistic circumstances, respectively. WECCs in the upper and lower reaches are the best and worst, respectively, which is in line with the levels of economic development in the Dongjiang River Basin. The proposed method can also be applicable to many other problems involving numerous indicators. • Traditional VFPR model was improved from both model structure and model parameters. • A systematic framework was proposed for continuous and comprehensive evaluation of WECC. • Water ecology and the uncertainty in indicator values were considered in the index system. [ABSTRACT FROM AUTHOR]

This paper aims to present a new quantitative systematic approach to evaluate the effectiveness of utilizing and allocating resources based on the concept of "Work" in physics. This method is examined in the Urmia Lake Basin (ULB), shrinking of which has threatened the life of about five million inhabitants and ecosystem biodiversity. In the proposed approach, the role of three types of financial, human, and environmental resources in the development process is evaluated quantitatively, and they have been compared in two periods before and after the severe reduction of the lake water volume. Results show that although financial resources have increased by 1.9 times in the second period, the effectiveness of the development process has decreased. Therefore, the resources have not been utilized properly in a direction compatible with sustainable development strategies. Additionally, the improperly-spent financial resources on the development projects especially in the second period have had a more destructive role than the human and environmental resources in the ULB crisis. • A new quantitative approach is presented to assess the effectiveness of resource allocations. • The proposed approach is based on the concepts of force and work in physics. • Application of the approach is evaluated in Urmia Lake shrinking of which has threatened life of inhabitants. • Financial resources utilized in an unsustainable manner are the main reason for critical adverse conditions of the lake. [ABSTRACT FROM AUTHOR]