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The over-exploitation of groundwater resources is a significant concern due to the potential risks associated with the depletion of this valuable freshwater source. Future planning must consider changes in groundwater availability and urban expansion which are critical for understanding urban growth patterns. This study aims to investigate the impact of land cover change on groundwater depletion. Further, the Land surface temperature (LST) analysis has been performed to find the spatial spread of urbanization and its impact on surface temperature. The Gravity Recovery and Climate Experiment (GRACE) data for groundwater storage monitoring and Landsat data for land cover and LST mapping have been used. The GRACE-based Groundwater Storage (GWS) anomaly has been correlated with Tropical Rainfall Measuring Mission (TRMM)-based precipitation data. The GWS is further cross validated with the groundwater monitoring stations in the study area and the correlation of 0.7 is found. The time series analysis of GWS and the land cover maps with a decadal interval from 1990 to 2020 has been developed to find the impact of groundwater change due to urbanization. The results demonstrate a rapid increase in groundwater depletion and urbanization rates over the past decade. The LST spatial pattern is increasing similarly with the study area’s urban expansion, indicating the temperature rise due to urbanization. The study highlights the limitation of effective policies to regulate groundwater extraction in urban areas and the importance of proper planning to ensure the long-term sustainability of freshwater resources.

In recent years, the health conditions of the elderly (the middle-aged and the old, which for this study means people over 50 years of age) have deteriorated along with the aggravation of air pollution, which led to the change of medical insurance costs. This phenomenon is particularly prominent in developing countries, such as China. A total of 15,892 research subjects from 56 prefecture-level cities in 23 provinces were collected from the database of China Health and Retirement Longitudinal Survey (CHARLS). We investigated the effects of air pollution, physical health, and medical insurance costs among three mechanisms using logistics and Ordinary Least Squares (OLS) hybrid cross-sectional regression, and we conducted a robust test. Overall, two pollutants, namely, PM10 and NO2, respectively showed an “inverted U-shaped” and “positive U-shaped” influencing path to health. In addition, when we studied the mechanism of air pollution affecting medical insurance costs, we found that air pollution can affect medical insurance costs through affecting self-rated health, and that the impact path is related to different diseases to some extent. At the same time, there was a certain negative correlation between air pollution and medical insurance: The higher the degree of air pollution, the worse the self-rated health, and the fewer opportunities there are to purchase medical insurance. It can be seen that air pollution affects the physical health of middle-aged and elderly people, thus indirectly and negatively affecting the medical insurance cost. Further research also found that the types of air pollutants in southern and northern China showed some differences. Specifically, NO2 and SO2 were the pollutants that harm the health of the elderly in the south and north, respectively.

International economic cooperation accelerates the flow of capital, technology, labor, and other factors between different countries, which promotes global sustainable development. Building infrastructure construction is an important way to strengthen social development, and absorbing foreign capital is an effective way for developing countries to improve their infrastructure and to promote economic development. This study puts forward the factors that have influenced China’s investment in international engineering projects, and it constructs a panel data regression model for empirical testing. The study shows that, first, international infrastructure investment tends to select countries or regions with good condition of highway infrastructure. Second, international infrastructure investment tends to choose countries or regions with low development level of port and power infrastructure. Third, bilateral diplomatic visits play a significant role in promoting international infrastructure investment. Fourth, international infrastructure investment tends to choose countries or regions with good resource endowment. This study reveals the influencing factors and the mechanisms for the choices of location for China’s investment in international engineering projects, providing a theoretical framework for investors to optimize international infrastructure investment and management, as well as providing the policy references for developing countries to attract international infrastructure investment.

We used the hyperbolic Drucker–Prager and damage-failure models to simulate a three-dimensional rock fragmentation with a tunnel boring machine (TBM) disc cutter through ABAQUS. The energy entropy method was proposed to identify the optimal disc cutter spacing. In order to verify the results of the numerical simulation, previous linear cutting machine (LCM) test data were referred to. The results of the numerical simulation were verified by comparing the mean rolling force and the specific energy against the corresponding values from the LCM tests. The proposed energy entropy method showed a good agreement with the LCM test results, thus proving its usefulness in analyzing rock fragmentation for various disc cutter spacings. The comparison between energy entropy and the specific energy showed that both methods provide similar conclusions with regard to optimal spacing. The results of this research showed that energy entropy can predict the performance of TBM disc cutters and could help improve their design.

Urban ecosystem services provide many benefits for human beings. Given the dramatic increase of urbanization, maintaining sustainability of cities relies heavily on ecosystem services, and it is crucial for quantifying, managing, and optimizing urban ecosystem services to promote social and ecological sustainable development. This study presents the review of models for assessing urban ecosystem services through gathering the pertinent literatures which were published recent years. The main types of approaches for assessing urban ecosystem services were summarized, and the model simulation approach was detailed. From modelling techniques to the existing models, it was found that a process-based model is, relatively, a better way to detect the mechanism of urban ecological processes and simulate the future dynamic changes of urban ecosystem services. Three key limitations of existing products and frameworks were identified: (1) lacking understanding of multiple urban ecosystem services interactions, (2) ignoring accounting the socioeconomic factors into dynamics of urban ecosystem, and (3) lacking considerations of feedback effects between social system and urban ecosystem. The study concludes with outlooks that a comprehensive social-ecosystem model based on the social-ecological framework is helpful to reveal the relationships and interactions among various urban ecosystem services, and can better assess how human-induced urban growth affects ecosystem services, and better describe the feedback effect between the social environment and urban ecosystem services, as well as dynamically predict the changes of urban ecosystem services under different scenarios in future long time series.

A transit ridership study is an essential part of sustainability, and can provide a deep understanding of people’s travel patterns for efficient transportation development and urbanization. However, there is a lack of empirical studies comparing subway and taxi services, and their interactions within a city, that is to say, the interdependent transportation networks. Incorporating new data, this study aims to examine the spatial variation of urban taxi ridership due to the impacts of a new subway line operation opened in 2014 in Wuxi, China. We examine the spatial patterns and interactions of ridership in Wuxi by integrating taxi trajectory from GPS data and subway data from continuously collected fare transactions. The results indicated that the demand for taxi and subway usage is quite elastic with respect to both location and time, and the new subway’s opening had more influence on areas adjacent to subway stations and urban center-suburban travel. Furthermore, increases in travel time and distance would increase the demand for subway, while taxi trips largely represented movements for those locations that the subway could not reach. This paper betters the understanding of travel patterns through large volumes of transportation data for sustainable urbanization policy design.

The neglect of endogenous strength is one of the reasons for the lack of sustainability in mountainous rural development and tourism development in China at present. How to incorporate the opinions of villagers in the tourism development process led by the government and other external entities is the main focus of this article. Based on the fieldwork of two typical mountainous villages and a previous rural development evaluation method, this article proposes the villager-satisfaction-based evaluation method for tourism village development, covering rural settlement construction, village esthetics, and economic and social development. “Villager satisfaction” is a crucial indicator obtained by objectifying the subjective opinions of villagers. Finally, the evaluation method was applied in the form of a questionnaire in two villages. The experimental results are correlated with the tourism development patterns of the two villages, verifying the feasibility and effectiveness of the evaluation method. It is expected that this evaluation method will become an effective communication medium between non-professional villagers and the professional tourism development process, thereby promoting the sustainable development of rural areas in the future.

Through field perception in winter and summer, people’s preferences for vegetation types in green spaces with various structures (single-layer woodland, tree-shrub-grass composite woodland, tree-grass composite woodland, and single-layer grassland) and concrete and asphalt sites (areas) without plants are evaluated. The results show the following: (1) There are significant differences in landscape preference between the two seasons, and the environmental perception preference score for landscapes in summer is higher. (2) The preference score for the vegetation types in green spaces was single-layer woodland > tree-shrub-grass composite woodland > tree-grass composite woodland > single-layer grassland > concrete and asphalt sites (areas). The preference score for the single-layer woodland landscape in winter was significantly higher than that in summer. (3) The preferences of participants to carry out activities vary by season and the magnitude of thermal comfort; notably, rest and communication activities in green spaces with high thermal comfort, such as tree-shrub-grass composite woodland and single-layer woodland areas, are preferred in summer, and physical activities in the single-layer woodland landscape are preferred in winter. (4) Regardless of which environmental perception method is adopted, landscape preferences did not significantly differ by sex or professional background. Based on the above results, the two seasonal perception methods cannot replace each other. Therefore, the types of activities should be carefully selected to be appropriate for the specific vegetation types in green spaces and season in which they will occur, and the green space should be reasonably planned according to the thermal comfort of the vegetation types to provide a scientific basis for evaluating landscape perception and preferences in the future.