Carrying Capacity Of Water Resources Research Articles

Study on Water Resource Carrying Capacity of Zhengzhou City Based on DPSIR Model.

Based on the driving force-pressure-state-impact-response (DPSIR) model, a comprehensive evaluation index system is constructed. The index weight is determined by the combination weighting method in combination with the data of 2010-2019. The TOPSIS model is used to comprehensively analyze the water resource carrying capacity of Zhengzhou as the central city in China with a developed economy and relatively short water resources. The study results are as follows. (1) During the sample period, the comprehensive evaluation value of water resources carrying capacity of Zhengzhou increases from 0.4183 in 2010 to 0.5560 in 2019, with an overall fluctuating rise. Simultaneously, the water resource carrying capacity grade improves from Grade III (normal carrying capacity) to Grade II (good carrying capacity). (2) The contribution of each subsystem to the comprehensive evaluation value increases year by year. Among them, S subsystem and I subsystem make the largest contribution to the comprehensive carrying capacity. R subsystem makes a relatively stable contribution to the overall carrying capacity. Affected by GDP growth rate and uneven temporal-spatial distribution of water resources in Zhengzhou, the D subsystem and P subsystem of water resource carrying capacities show the fluctuating change. Finally, based on the above conclusions, this paper puts forward the countermeasures and suggestions to improve the level of water resource carrying capacity of Zhengzhou.

Predicting the Evolution Trend of Water and Land Resource Carrying Capacity Based on CA–Markov Model in an Arid Region of Northwest China

The evolution of water and land resource carrying capacity significantly impacts optimal water and land resource allocation and regional sustainable development in arid regions. This study proposes a model that combines cellular automaton (CA) and Markov; this model aids in predicting spatial changes in water and land resource availability. In this study, taking the Jingdian Irrigation District in China’s northwest arid region as an example, we used long-series monitoring data and a Landsat dataset to create a raster-weighted fusion of 18 indicators and quantitatively analyzed the carrying status of water and land resources from 1994 to 2018. The CA–Markov model was used to simulate the carrying status of water and land resources in 2018 and to perform accuracy correction. The validated CA–Markov model was used to predict water and land resource carrying status in 2026 and 2034. The results show (1) from 1994 to 2018, the area of “good carrying” zone increased by 10.42%, the area of “safe carrying” zone increased by 7%, and spatially rose in an arc from the town to the surrounding regions. The area of “critical carrying” zone remains almost unchanged. The area of “slight carrying” zone decreased by 5.18% and the area of “severe carrying” zone decreased by 11.99%. (2) Comparing the actual and predicted carrying state of water and land resources in 2018, it was found that the simulation accuracy of “good carrying”, “safe carrying”, “critical carrying”, “slight carrying”, and “severe carrying” reached 98.71%, 92.07%, 95.34%, 94.05%, and 93.73%, respectively. This indicates that the simulation results have high reliability and applicability. (3) The future medium and long-term carrying status of water and land resources are healthy, but this trend is gradually slowing. The “slight carrying” and “severe carrying” zones show the gradual spatial transition from land desertification to soil salinization.

Analysis of Water Resource Carrying Capacity and Obstacle Factors Based on GRA-TOPSIS Evaluation Method in Manas River Basin

The investigation of water resource carrying capacity (WRCC) in oasis cities in Northwest China is useful for guiding the sustainable development of arid regions. To quantify the WRCC of Shihezi, an oasis city in the Manas River Basin (MRB), Northwest China, a total of 21 indicators from three subsystems were selected to construct an evaluation index system based on the theory of the water resource–socio-economic–ecological complex system. Our study utilized a combination of the CRITIC method and the entropy weight method to determine the synthesis weight, the GRA-TOPSIS approach to comprehensively evaluate the WRCC, and the obstacle degree model to identify its main obstacle factors. Our results showed that the WRCC of Shihezi showed an increasing trend from 2011 to 2020, with the compositive index increasing from 0.3454 to 0.5210. The carrying capacities of the ecological environment and socio-economic subsystems were generally on the rise, but the rate of change was relatively gentle from 2017 to 2020. The carrying capacity index of the water resource subsystem dropped significantly from year to year from 2016 to 2020. The irrigation coverage rate, the proportion of agricultural water, water consumption per 10,000 CNY of GDP, the modulus of water production, water resource development and its utilization ratio, the water supply modulus, and the proportion of ecological water were the seven most significant obstacles. Our findings could serve as scientific references for enhancing WRCC and promoting the sustainable development of oasis cities in arid regions.

The driving effect of spatial-temporal difference of water resources carrying capacity in the Yellow River Basin

Water resources is one of the basic resources for human social development. In the context of China's rapid economic development, how to achieve the sustainable development of water resources, social economy and ecological environment has become an urgent issue. Water Resources Carrying Capacity (WRCC) is an important indicator of the degree of coordinated social, economic and ecological development that can be supported by water resources in a certain region. Based on the internal mechanism of WRCC, this paper constructs the evaluation system of WRCC, and estimates WRCC of 9 provinces in the Yellow River Basin (YRB) from 2009 to 2018 by the entropy method. Using the Logarithmic Mean Divisia Index (LMDI) model, we analyze the driving effects of WRCC differences in the YRB from both spatial and temporal aspects. Main conclusions are as follows: (1) There is an inherent mechanism between water resources, social economy and eco-environment, and the coordinated development of the three subsystems can promote the improvement of WRCC; (2) From 2009 to 2018, WRCC of the YRB showed a relatively stable upward trend, in which the sewage treatment effect and the technical effect were the main factors promoting WRCC, while the economic effect had a negative weakening function throughout the research period; (3) There were obvious differences in the WRCC of each province. We choose Shandong and Gansu as the comparison objects, then analyze the factors causing differences of WRCC through the driving effects decomposition analysis.

Prediction of Settlement Growth in Meulaboh Urban Area (MUA) and Its Implication for Carrying Capacity

Population growth affects the competition between land uses. Inevitably, the increasing demand for natural resources causes severe damage to the urban environment. In addition, the potential of water resources can be a problem related to the supply of clean and suitable water to the community. The geological structure of the soil, disaster susceptibility, and issues with the clean water supply at the location are challenges in determining the development of residential areas in the Meulaboh Urban Area (MUA). This study aims to determine the carrying capacity of the Meulaboh urban settlement environment and the model for the distribution of settlements in the MUA. The environment’s carrying capacity is reviewed based on two aspects: the carrying capacity of settlements and water resources. In analyzing settlement modeling using MLC data from time-series images of Google Earth and Landsat 8-9 in 2011, 2016, and 2021 and using the MOLUSCE plugin on QGIS. The environmental carrying capacity assessment results show that the level of carrying capacity of settlements in the MUA is currently worth 1.69, and in 2041 it will reach a value of 1.26. While the carrying capacity of water resources in the current year is at a value of 2.8, and in 2041, it will reach a value of 2.0. Until 2041, it can still accommodate the population and meet the water needs to support population growth. However, it must still consider the disaster aspects and existing environmental constraints. So that sustainable development can be created that can balance development and the environment in the region.

Simulation of water resources carrying capacity of the Hangbu River Basin based on system dynamics model and TOPSIS method

Water resources play a key role in development. The research on water resources carrying capacity (WRCC) is helpful to judge the development status and provide suggestions for regional policy-making. In this study, the System Dynamics (SD) model and the Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) method are combined to calculate the change of WRCC of the Hangbu River basin from 2015 to 2035 under four development scenarios. The results show that WRCC of each scenario decreases first and then increases. The scenario that prioritizes water resources is the best for the Hangbu River Basin, under which the WRCC will increase to 0.631 in 2035, achieving a good level. This is different from other WRCC studies. Through analysis, the research method and the development level and focus of the study area may be the reasons for this difference. In addition, some suggestions were provided such as focusing on improving the efficiency of irrigation water use and looking at the long-term development of the region.

Water resource carrying capacity and obstacle factors in the Yellow River basin based on the RBF neural network model.

The Yellow River basin (YRB) plays an important role in China’s economic and social growth. Based on different dimensions, we adopted the radial basis function (RBF) neural network model and the obstacle degree model to examine the water resource carrying capacity (WRCC) of the YRB. From 2005 to 2020, the WRCC of the entire YRB, as well as the upstream and midstream regions, improved, but the WRCC of the downstream region remained poor, revealing spatial differences. The overall improvement in the WRCC of the Yellow River’s nine provinces is good, but the WRCC of Inner Mongolia and Henan is poor, suggesting regional differences. From the standpoint of obstacle factors, the development and usage rate of surface water resources are the main challenges. In 2020, the obstacle degree of the YRB reached 87.4871%. The irrigated area rate in Gansu was the primary obstacle factor, and the obstacle degree reached 73.0238%. Qinghai’s industrial aspects mostly hindered the improvement of its WRCC, with an obstacle degree of 31.36%. The results provide a theoretical reference for the high-quality development of the YRB.

Assessment of the Water Resources Carrying Capacity in the Great Dunhuang Region

Water resources carrying capacity (WRCC) is an important index for assessing the coordinated development relationship between population and water resources. The quantitative evaluation of WRCC can provide an important basis for water resource regulation and sustainable economic and social development. Based on the statistical data of cities and counties in the Great Dunhuang Region (GDR), and taking counties as the basic units, this study quantitatively analyzed the WRCC and carrying status of the GDR under different water inflow conditions and policy constraints from 2010 to 2017. The study revealed three main trends. (1) From 2010 to 2017, the WRCC of the GDR increased year by year, from 343700, 315900 and 291100 people to 458700, 415400 and 375600 people in normal, dry and extremely dry years, respectively. (2) Under policy constraints, the WRCC of the GDR increased year by year from 309400 people in 2010 to 412400 people in 2017. Based on future estimates, the WRCC of the GDR are expected to be 326600 people in 2020 and 341200 people in 2030. (3) From 2010 to 2017, the water resources carrying index of the GDR was decreasing, and it decreased from 1.05, 1.14 and 1.24 to 0.80, 0.88 and 0.97 in normal, dry and extremely dry years, respectively. The carrying status changed from critical overload to balanced. Although the WRCC and the carrying status of the GDR had significantly improved by 2017, the overall upper limit of the carrying capacity is not high. Therefore, efforts should be made to improve the utilization efficiency of water resources in order to maintain the sustainable utilization of water resources in the GDR.

Evaluating water resources carrying capacity of Pearl River Delta by entropy weight-TOPSIS model

To understand the spatio-temporal changes in the water resources carrying capacity (WRCC) of Pearl River Delta (PRD), 19 indicators were selected from three subsystems (water resources, socio-economic, and eco-environment), and the entropy weight-TOPSIS model was employed to analyze the WRCC of each cities in PRD from 2015 to 2020. As the result shows, the water resources subsystem (WRS) had the largest weight in the evaluation system, followed by the socio-economic subsystem (SES), and the eco-environmental subsystem (EES); among these indicators, economic density, water resources per capita, annual precipitation, and new soil erosion treatment area had the highest weights; the PRD had a low WRCC score overall, with considerable regional differences; the capacity score changed with time, but the ranking of cities remained largely the same, with Shenzhen, Zhaoqing, and Huizhou marking higher scores, whereas Zhongshan, Foshan, and Zhuhai achieving lower scores. It was also found that Shenzhen had a high score for SES, which made up for the shortage of natural water resources there; cities like Huizhou, Jiangmen, and Zhaoqing which boast rich water resources and extensive development achieved high scores for WRS and EES. As the PRD develops, it is important to optimize dispatch of water resources, boost green economy, and promote ecological wellbeing.

Evaluation of water resources carrying capacity in ecologically fragile mining areas under the influence of underground reservoirs in coal mines

The coal mine underground reservoir (CMUR) technology effectively solves the problem of “rich coal, poor water and weak ecology” in the mining areas of northwest China. This technology not only makes full use of underground space formed by coal mining, but also protects regional water resources. Water resources carrying capacity (WRCC) is an important indicator for characterizing the sustainable development of regional water resources and ecosystem. With the concept and technical core of " conductivity, storage and use" of CMUR as the entry point, this paper defines the concept of WRCC in the mining area. Based on the fuzzy comprehensive discrimination method, Focusing on stability and sustainability of the ecosystem in the mining area and fully considering geological factors, mining factors, water resource factors, this study constructs an evaluation system for the WRCC of the mining area under the influence of the coal mine underground reservoir based on fuzzy comprehensive discriminant method. Moreover, the evaluation criteria are formulated, and the membership functions and weights of 16 impact factors are derived. The transformation characteristics of WRCC with and without underground reservoir in Shendong mining area from 2009 to 2021 are evaluated CMUR, and the results show that CMUR improves the WRCC of the mining area, and supports the benign development of the regional ecosystem. The results of this study are of reference value and academic significance for the evaluation of WRCC in mining areas and the protection of water resources in ecologically fragile mining areas.

Comprehensive comparison and assessment of three models evaluating water resource carrying capacity in Beijing, China

Water supply is one of the most critical factors for food security in many parts of the world, and the balance of water supply and demand ensures the sustainability of water resources. The water resources carrying capacity (WRCC) can effectively evaluate the state of sustainable development of water resources. Taking Beijing, which is severely lacking in water resources, as an example, the five-element subtraction set pair potential, logistic, and Technique for Order Preference by Similarity to Ideal Solution evaluation models (TOPSIS) were comprehensively compared and assessed to identify a more suitable method for water resource assessment. The results indicate that Beijing's WRCC score substantially improved from 2010 to 2018. The overall WRCC of Beijing has improved from the perspective of the carrying subject subsystem, and this has been particularly evident since 2014. The change of quantity and quality index in the quantity-quality-water bodies-flow index layer was the main reason for the increase in Beijing's WRCC. The South-to-North Water Transfer Project had a major impact on the changes in the quantity and quality index layers, which was reflected most distinctly in the measures of per capita water resources and Chemical Oxygen Demand (COD) emissions per 10,000 yuan. From the perspective of carrying object, Beijing’s carrying capacity has improved significantly since 2013. In terms of utilization and social development, water consumption per 10,000 yuan of GDP and the proportion of tertiary industry are important factors affecting WRCC. Of the evaluation results of the three models, the results of the five-element subtraction set pairing evaluation model exhibited the highest accuracy. The results may also reflect the indicator status to a certain extent, and the results were more consistent with Beijing's WRCC. This study accurately identified the advantages and disadvantages of various indicators of WRCC by comparing different models and provided a reference for the formulation of Beijing's regulation measures for the sustainable development of water resources and food security.

Comprehensive evaluation on water resources carrying capacity based on water-economy-ecology concept framework and EFAST-cloud model: A case study of Henan Province, China

Water is the basic need for human survival and the development of economy and ecology. Water resources carrying capacity (WRCC) modelling is a fundamental task to explore the interaction mechanism between economy-ecology development and water resources carrying system. To reasonably quantify the regional WRCC, an evaluation method based on Water-economy-ecology (WEE) concept framework and EFAST-Cloud model is proposed in this study, and Henan Province of China is selected as a typical study area. It can both identify the inter-feeding relationships between sub-systems and evaluate the proportion of each grade in detail by reflecting the randomness and fuzziness of the evaluation. A total of 15 indicators including water system, economy system, and ecology system are constructed. The study analyzes the sensitivity of indicators by using Simlab software and then calculates the weight of indicators by using EFAST method. Compared with other traditional methods, EFAST algorithm is a special method for model sensitivity analysis, which can fully consider the coupling effect between indicators. According to the statistical data of 2010, 2015, and 2020, the WRCC at the watershed scale and municipal scale in Henan Province are evaluated through the EFAST-Cloud model. At the watershed scale, the ecology system criterion layer performs best over the multiple years, the Huaihe and Yangtze River basin have better WRCC at the target layer. At the municipal scale, Xuchang, Luohe, and Zhumadian have better WRCC, Puyang, Zhoukou, and Jiaozuo are slightly worse. The results show that WRCC of the study area has shown an overall improvement, but there is still much space for its development. Therefore, targeted recommendations are made for the water, economy, and ecology system respectively. The conclusion of this paper can provide a reference for the government in making water resources management policies.

Evaluating water resources carrying capacity: The empirical analysis of Hubei Province, China 2008–2020

Scientific evaluation of water resources carrying capacity (WRCC) is the basis for implementing water resources conservation measures. Hubei Province, with the longest runoff mileage of the Yangtze River, the reservoir area of the Three Gorges Project and the core water source area of the South-to-North Water Diversion Middle Line Project, bears great responsibility for ecology conservation in China. How to evaluate WRCC in Hubei Province has become significant. This study created a WRCC evaluation method based on information entropy method, principal component analysis and Spearman’s rank correlation coefficient to assess the WRCC in Hubei Province from 2008 to 2020. The available indicators were collected and summarized from the aspects of economy, population, resources and environment. By three-dimensionally displaying different indicators’ eigenvalues of principal component analysis, the major indicators can be screened. Subsequently, information entropy method was applied to estimate WRCC in Hubei Province and Spearman’s rank correlation was examined between WRCC and relevant factors. The results indicated that the WRCC in Hubei Province had been unstable in the range of 0.065 to 0.088 with the annual growth rate of 0.096%. It had a few peaks in year 2010, 2012, 2014, 2015 and 2016 while it decreased dramatically in year 2009, 2011, 2013, 2018 and 2020. Specifically, agricultural water use is more influential than industrial water use. The annual decline at 1.865% in agricultural water use is much smaller than the annual decline at 10.471% in industrial water use. Economically developed areas in the province have higher WRCC while economically backward areas have weaker WRCC.

Spatiotemporal Heterogeneity and Driving Factors of Water Resource and Environment Carrying Capacity under High-Quality Economic Development in China.

Rapid economic growth and social development in China have led to serious water pollution problems and water resource shortages, limiting the sustainable development that could support both the socio-economy and water resources carrying capacity (WRECC). However, the spatial heterogeneity and evolutionary characteristics of the coordination between the WRECC and economic development have not been adequately explored in China. In this study, we developed the support and pressure indicators of China’s 30 provinces and then analyzed the spatiotemporal distribution and evolution characteristics of their WRECC by using the geographically and temporally weighted regression (GTWR) model. The main findings are shown in the following: (i) From a temporal perspective, there has been an overall upward trend in the WRECC to support human activities; however, the WRECC level is not high. Approximately 63.7% of provinces remain in an overloaded state, indicating that the support indicator of most provinces is smaller than the pressure indicator imposed by human social activities. (ii) There are significant spatial differences in the WRECC indicators across provinces. Provinces with low-level WRECCs are concentrated in central China but decrease significantly from the country’s borders to its center. Eastern regions have a medium-level of WRECC with the greatest degree of regional difference, while western regions have a high-level of WRECC with the smallest degree of regional difference. The variation of WRECC is attributed to within-group differences in the three geographical regions in China. (iii) The factors that significantly impact the WRECC include population density, gross domestic product (GDP), temperature, urbanization, the added value of tertiary industry within the GDP, and R&D expenditures. GDP and R&D expenditures positively impact the WRECC, while the other four factors have different influences on the WRECC. (iv) The spatial distributions of driving factors show significant aggregation characteristics, with decreasing trends from the eastern to western regions and from the southern to northern regions. These findings present a comprehensive understanding of the current WRECC in China’s provinces which can be used as a reference for realizing environmentally sustainable water development strategies under high-quality economic development.

Comprehensive evaluation and scenario simulation of carrying capacity of water resources in Mu Us Sandy Land, China

Abstract With the rapid improvement in socioeconomic conditions globally, the demand for water resources has dramatically increased. Evaluating water resource carrying capacity (WRCC) is crucial for regional sustainable development. To date, limited attention has been paid to WRCC in areas of predominantly sandy land, with the impact of vegetation restoration in ecologically degraded areas on WRCC remaining unclear. In this study, using a comprehensive evaluation index and a system dynamics model, we evaluated the WRCC of the Mu Us Sandy Land, Inner Mongolia, China, from 2000 to 2019 then projected to 2030. Our results show WRCC has decreased since 2000, reaching a general state by 2019. In a future scenario where historical development remains unabated, WRCC will continue to decline to a poor carrying state by 2030. The comprehensive scheme based on industrial restructuring and water conservation performed the best in terms of WRCC, continuously increasing and returning to a general carrying state by 2030. Our findings highlight the WRCC of the Mu Us Sandy Land is not optimistic and subsequent ecological restoration should proceed with caution. A comprehensive scheme is an optimal development strategy for the future.

Assessing carrying capacity of regional water resources in karst areas, southwest China: a case study

Assessing carrying capacity of regional water resources in karst areas, southwest China: a case study

Evaluation of spatial variation of water resources carrying capacity using optimal method: a case study of Fujian, China.

Studying regional water resources carrying capacity (WRCC) is an important guarantee for realizing regional sustainable development. Previous evaluation of WRCC mainly focused on the construction of the index system and the optimization of multiattribute decision analysis methods (MDAMs). The selection of the weighting assignment method (WAM) is a key link in the evaluation of WRCC, but different WAMs may bring different results, which brings challenges to the actual WRCC evaluation. Therefore, this paper proposes a WAM selection framework, under which WRCC evaluation index system is firstly constructed. Secondly, from the four objective WAMs, the most suitable WAM is identified and selected to evaluate WRCC in Fujian Province in terms of the reliability and stability of the evaluation results. In addition, the main factors affecting regional WRCC are discussed using the obstacle degree model. The results show that (1) under the same evaluation index system, the CRITIC method was the suitable method with more reliability and stability than the coefficient of variation method, the entropy method, and the equal weight method. (2) The higher water resources carrying capacity (level I) is mainly located in the west of the study area, and the lower one (level V) is located in the east coast. (3) The superimposition effects ecological water use rate, water production modulus, acreage water consumption of farmland irrigation, per capita water resources, and COD emissions hindering the level of regional WRCC. The framework proposed in this study can provide methodological options for quantitative evaluation of WRCC. The results of this paper provide favorable support for decision makers to carry out rational planning of resources.

Decoupling of water resources utilization and coordinated economic development in China's Hexi Corridor based on ecological water resource footprint.

The rapid growth of population and economy leads to a further increase in demand for water resources. The contradiction between supply and demand of water resources has become the main bottleneck restricting sustainable development of a regional social economy. Accurate measurement of regional water usage and the harmonious balance between water consumption (WC) and economic growth (EG) are the premise of regional high-quality development. Based on this premise, this paper studied the arid oasis region, Hexi Corridor, as the research object; utilized the theory of ecological footprint to calculate the ecological footprint (EFW) and ecological carrying capacity (ECCW) of water resources from 2005 to 2019; and quantitatively analyzed the water utilization situation in Hexi Corridor in the past 15years. Then, combining with the coordinated development decoupling evaluation model, the connection between WC and EG was evaluated. The main results of this study were as follows: (1) During the study period, EFW has shown a fluctuating downward trend, decreasing from 1.745 in 2015 to 1.588 hm2/person in 2019. The average annual EFW per capita of 10,000 yuan of GDP decreased by 10.18%, which showed that the water resources utilization efficiency was gradually increasing. However, there was still a large water deficit. The average water ecological pressure index was 16.55; water resources were under great pressure. (2) From 2005 to 2019, the relationship between WC and EG experienced stages of strong decoupling-weak decoupling-weak negative decoupling-strong decoupling in Hexi Corridor, and the coordination between the two was gradually strengthened. (3) The decoupling status of the Hexi Corridor cities was gradually optimized. Zhangye was the best and in a stable decoupling state, followed by Wuwei and Jiuquan. The number of decoupling years accounted for 85.7% and 78.6% of the evaluation period, respectively. The cities with poor decoupling status were Jiayuguan and Jinchang, and the number of decoupling years accounted for 71.4% and 57.1%, respectively. This study provides some highlights for the formulation of arid oasis regional water strategy.

Analysis of the climate change impact on water availability and the links between water pollution and economy for sustainable water resource management in Kaski District, Nepal

Abstract The newly enacted national water policy is envisioned as ensuring water sustainability in Nepal. Despite theoretical pertinence, questions remain about the effective implementation due to limited studies on key aspects of sustainability, such as water supply and demand, pollution, and impacts of climate change and socio-economic growth. This study analyses the current and future availability of water under climate change scenarios and determines water resources carrying capacity (WRCC) as the maximum socio-economic growth that can be supported in a case study on the Kaski District, Nepal. Annual average water availability was estimated to be 11,030.7 million cubic meters (MCM) for the baseline period (1992–2010), and 7,677.4 and 7,674.2 MCM for the future period (2022–2050) under the representative concentration pathway (RCP) 4.5 and 8.5 emission scenarios, respectively. For the baseline period, WRCC far exceeds the current population; therefore, water resources will not be a limiting factor for local socio-economic development. Nevertheless, sustainable water infrastructure development policies are necessary to ensure a reliable water supply able to cope with increasing seasonal variability and declining future water availability. A total of 30,049 tons of biological oxygen demand (BOD) loads were estimated based on the economic activities of the Kaski District in 2011, with the direct and indirect sectoral roles of water pollution determined for the first time. Rather than a single pollution control strategy based on pollution loads, multiple sector-specific strategies are necessary to effectively implement water pollution control policies.

Assessment of coupling coordination degree and water resources carrying capacity of Hebei Province (China) based on WRESP2D2P framework and GTWR approach

• A multi-system multi-layer theoretical framework is proposed for the first time. • Sustainable development measures was selected as indicators. • Improved TOPSIS model is used to evaluate the water resources carrying capacity. • Standard deviation ellipses were applied to analyze the WRCC orientation. • WRCC and GTWR model are combined for the first time. Water resources system (WRS), socio-economic system (SES) and Ecological environment system (EES) are systems closely related to the sustainable development of cities. It is crucial to accurately evaluate the Water resources carrying capacity (WRCC) and the Coupling coordination degree (CCD) among the systems for sustainable development. The paper proposed a conceptual framework of Water Resources Endowment-Support-Pressure-Development-Destructiveness-Protection-Promotion(WRESP2D2P) and constructed an index system with 20 indicators. The improved TOPSIS model and Geographic spatiotemporal weighted model (GTWR) were applied to evaluate the water resources carrying capacity and analyze the key factors affecting the WRCC. Findings showed that (1) CCD in 11 cities of HBP are in a state of reluctant coordination from 2011 to 2018. (2) Although the Water resources carrying capacity index(WRCCI) of 11 cities is increasing, Water resources carrying capacity grade(WRCCG) of most cities are in Grades III and IV, which is in a state of critical carrying state and slight overload. (3) Spatially, the distribution pattern of WRCC of HBP changes from Northeast to Southwest. (4) The factors affecting WRCC have spatial and temporal heterogeneity. (5) The per capita water resources is the most dominant factor affecting the WRCC in HBP. The study proposed a multi-system, multi-layer index system, aiming to provide a scientific basis for urban sustainable natural resources management.