Factors affecting the environmental carrying capacity of a freshwater tropical lake system

Analysis and Evaluation of Variation Characteristics in Groundwater Resources Carrying Capacity in Beijing between 2010 and 2020

The problems of water shortages and groundwater overexploitation are serious in Beijing. Resources are over-exploited to meet the industrial needs of various sectors, and the capacity of groundwater resources to support economic development is also reduced. Therefore, it is of great significance to study the evaluation of regional groundwater resources carrying capacity from the perspective of time and space. This study evaluates the groundwater resource carrying capacity of Beijing from time and space by using the function between water use efficiency and groundwater availability constructed by regional water supply, consumption data and GDP data. The results show that: The proportion of groundwater in water supply in Beijing has decreased and it was still one of the main sources of water supply from 2010 to 2020. From the perspective of time, when the degree of groundwater exploitation (De) was greater than 1, the contribution rate of exploitation degree of economic development (Dg) reached 60% from 2010 to 2015, indicating that the economic development of Beijing is highly dependent on groundwater resources. From 2015 to 2020, the De was less than 1, but the Dg value kept increasing and approaching 90% and the total overload rate was 81.8%. The supporting capacity of groundwater resources will become more fragile. At the spatial scale, only the Dongcheng and the Xicheng regions were overloaded whose rates were 58.48% and 69.92%. The research shows that the degree of groundwater exploitation has approached the saturation state, the economic development is highly dependent on groundwater resources and there is a large space for water saving. Improving the utilization efficiency of water resources cannot improve the carrying capacity of groundwater resources, so it is still necessary to increase the amount of groundwater resources by recharging the groundwater through a series of comprehensive over-exploitation control measures, which is of great significance to the management and sustainable development of regional groundwater.

Temporal and spatial evolution and obstacle diagnosis of resource and environment carrying capacity in the Loess Plateau

Natural resources are scarce in the Loess Plateau, and the ecological environment is fragile. Sustainable development requires special attention to resource and environmental carrying capacity (RECC). This study selected 24 representative cities in five natural areas of the Loess Plateau; used the entropy-weight-based TOPSIS method to evaluate and analyze the RECC of each city and region from 2013 to 2018; established a diagnosis model to identify the obstacle factors restricting the improvement of RECC; and constructed the theoretical framework of the RECC system mechanism. The results show that the RECC of the Loess Plateau is increasing in general but is relatively small. The environmental and social subsystems have the highest and lowest carrying capacities, respectively. There is an evident contradiction between economic development and the environment. Population density, investment in technological innovation, per capita sown area, and per capita water resources are the main obstacles affecting the improvement of RECC in the Loess Plateau. Such evaluations and diagnoses can support ecological civilization and sustainable development.