Research on Comprehensive Evaluation and Coordinated Development of Water Resources Carrying Capacity in Qingjiang River Basin, China

Evaluation of water resource carrying capacity in the middle reaches of the Yangtze River Basin using the variable fuzzy-based method

The middle reaches of Yangtze River Basin (MYRB) are rich in water resources, with a large number of rivers and lakes. However, in recent years, water resources from this basin are no longer sufficient to support the region's rapid economic development. This study established a model to evaluate the water resource carrying capacity incorporating water resources, population, and socio-economic data. The characteristic values of water resource carrying capacity were calculated using the variable fuzzy evaluation method in MYRB from 2005 to 2020. Although both population and GDP in the MYRB showed an increasing trend between 2005 and 2020, the water supply capacity increased and then decreased. The weights of each index for evaluating the water resource carrying capacity of perennial botanical gardens were as follows: degree of water resource development (0.311) > total water resources (0.24) > population density (0.156) > GDP per capita (0.097) > water resources per capita (0.077) > water supply per capita (0.064) > water resources per unit area (0.055). Furthermore, the water resource carrying capacity in the MYRB showed an increasing trend from 2005 to 2020. In 2020, the carrying capacity of water resources in Changsha, Jingmen, Xiangtan, Hengyang, Wuhan, Xiaogan, Nanyang, and Xiangyang was attributed an evaluation grade of level 3, which indicates that the development and utilization of water resources in these areas were at their saturation point.

Assessment of the Carrying Capacity and Suitability of Spatial Resources and the Environment and Diagnosis of Obstacle Factors in the Yellow River Basin

The assessment of the carrying capacity and suitability of spatial resources and the environment can provide effective guidance for regional planning and make vital contributions to the high-quality advancement of society and the economy. Additionally, this scientific evaluation of the spatial carrying capacity and suitability of urban production-living-ecological space (PLES) has important scientific value as well as practical significance for territorial spatial planning. This paper takes the cities along the Yellow River Basin (YRB) as the research object; establishes the PLES resource and environment carrying capacity evaluation index system; uses the multi-indicator superposition method and entropy weight method to evaluate the ecological importance, production and life carrying capacity of 78 cities in the YRB from 2010 to 2020; obtains the final ecological importance, production and life suitability levels based on the carrying capacity combined with the location conditions; and uses exploratory spatial data analysis (ESDA), the barrier degree model and other methods to determine the cities' spatial and temporal patterns and influencing factors. The findings indicate that: (1) Ecological importance is characterized by "high upstream and low downstream"; the suitability for production is higher mainly in the eastern coastal area; the suitability of life as a whole is increasing, and the higher grade is in some provincial capitals and surrounding cities. (2) The local Moran's I all passed the test, and the relationship between PLES showed a significant positive spatial correlation. The clustering characteristics of ecological importance and production suitability are strong, while the clustering characteristics of suitability for living functions are relatively weak. (3) Biodiversity, significance of water conservation and significance of wind and grit control functions are the main barrier factors affecting the ecological importance of the YRB; industrial value-added output per unit of industrial land, number of industrial enterprises above the scale and GDP per capita are the dominant factors affecting the production suitability of the study area; total water-resource utilization per capita, total sewage treatment per capita and residential land area per capita are the main barrier factors of living suitability.

An Improved Approach of Integrated Carrying Capacity Prediction Based on TOPSIS-SPA

Regional coordinated development is an important policy to promote socio-economic development, especially in the Yangtze River Delta, Greater Bay Area and others, which is one of the guidelines of the 14th Five-Year Plan for economic development. The relative stability of the carrying capacity (CC) is the precondition for long-term rapid development, whereas the comprehensive capacity of natural resources, ecological environment, social economy, population and others, defined as integrated carrying capacity (ICC). Due to the complexity of the CC quantitative assessment, constructing an accurate ICC predication model is the core challenge of dynamic adjustments of socio-economic development planning. In this study, four critical issues, which focused on indicator value estimation, optimal ICC value screening, ICC tendency prediction and study area application in order to formulate a novel prediction framework, are investigated as follows: (1) The proposal formulated an estimation model of indicator value in the future based on the grey model. The grade ratio and the relative residuals of all third-class indicators are less than 0.1, which is highly accurate for indicator value estimation. (2) The optimal ICC value screening model was proposed based on the multi-objective decision-making theory. The optimal ICC values of Suzhou, Ningbo and Zhoushan were 0.7002, 0.6797 and 0.5982, which were also the maximum values from 1996 to 2019. However, the values of Nantong, Jiaxing and Shaoxing were recorded in 2018, 2001 and 1999, which were not the maximum ICC values, and the difference ratio was more than 10%. The optimal ICC value of these three cities were improved. (3) The ICC prediction model was constructed based on the theory of set pair analysis and Euclidean distance. The ICC prediction result of eight cities maintained a relative fluctuation during 2020–2030. Compared with the polynomial fitting curve predication, there were some differences in Nantong, Shaoxing and Zhoushan over the next 5 years. This study provided an improved approach of ICC prediction model, focusing on indicator weight, indicator data estimation and optimal ICC value screening. The model and conclusion aim to validate the rationality of economic planning target for government policymakers and stakeholders.