As an important subsystem describing rural development, the mutually beneficial symbiosis of rural settlements and cultivated land is crucial for sustainable rural development. Under the heterogeneous physical environment of Gansu province, 1384 townships were taken as the research units, and the symbiosis theory was introduced to construct a framework for the symbiosis between rural settlements and cultivated land. We construct a system of indicators for evaluating rural settlements, cultivated land, symbiosis environments, and identify their symbiosis patterns with the help of the Lotka-Volterra model. In the context of the new round of territorial spatial planning, the SD-FLUS coupled model is used to compare and analyze the evolutionary trends of symbiosis patterns under the baseline development scenario (BD) and the planning development scenario (PD) in 2035. The study found that: (1) The development level of rural settlements and cultivated land in Gansu shows a trend of first increasing and then decreasing, and the symbiosis environmental capacity shows a continuous decreasing trend. Three indicators of the five agricultural zones have significant differences. The irrigated agriculture area of the Hexi Region (IA) has an obvious advantage in the regional development. (2) The overall pattern of symbiosis between rural settlements and cultivated land in the province showed a shift from mutually beneficial symbiosis to mutually detrimental symbiosis, with the proportion of mutually beneficial symbiosis decreasing from 59.80% to 38.97%. There were significant differences in dominant patterns between regions. Alpine pastoral area (AP), mountainous agricultural area (MA), and IA are dominated by mutually beneficial symbiosis, while dry agricultural area (DA) and rain-fed agricultural area (RA) are dominated by rural settlements-bias and cultivated land-bias. During the 21-year period, the dominant pattrens of each region tended to be diversified and showed a commonality in the transformation from mutually beneficial symbiosis to mutually detrimental symbiosis. (3) The symbiosis relationship between rural settlements and cultivated land varies significantly under different scenarios. In the BD scenario, the five regions continue the historical rough development pattern, and the proportion of mutually beneficial symbiosis continues to decrease. In the PD scenario, the symbiosis pattern evolves to mutually beneficial symbiosis due to the improvement of symbiosis unit and environmental development level.

Shanghai is one of the most significantly urbanized cities in modern China, and its urban spatial pattern and urban area have changed dramatically since its opening up (1843-2020). Reconstructing and analyzing the expansion process of Shanghai has great importance toward attaining a deeper understanding of China's urbanization. This study collected multi-source and multi-precision urban spatial data such as old urban maps, topographic maps of the Republic of China (1912-1949), declassified images from the U.S. military (KeyHole), and remote sensing data (Landsat), and reconstructed a long time series of urban built-up areas, and finally examined the evolution process and driving forces of the spatial structure of Shanghai. The results show that: (1) Since 1843, the area of urban built-up areas increased tremendously, with a total expansion of about 1453 times, and the expansion rate and expansion intensity also changed drastically. (2) The overall change trend of compactness is decreasing, and the fractal dimension shows a certain cycle. (3) The center of gravity of the built-up area in different periods showed a trend of developing first to the north and then to the south, and the most important direction of expansion was southwest and west by south. (4) The urban change was complicated by multiple driving factors: the natural location established the prerequisite for the development of Shanghai as a port city; as the most fundamental driving force, social change and policy determined the main direction of urban development at different stages; the spatial agglomeration of industry and trade is the direct cause of the formation and expansion of cities; population migration also injected new impetus into the urbanization; transportation, as an urban infrastructure, has been used to strengthen the connection between the city's external and internal regions. This study clarifies the processes and mechanisms of urban expansion in Shanghai and provides historical knowledge and scientific support for a deeper understanding of urban change and the evolution of the human-land relationship. Moreover, the ways in which a set of general data with a wide coverage and high resolution can be used for the study of the spatial and temporal processes of urban expansion on a centennial scale are discussed, which is quite instructive for understanding the pre-remote sensing era and developing longer time series.

Ecological risk (ER), ecosystem health (EH), and ecosystem services (ESs) are key features that describe the status of regional ecological security. While ER and EH respectively represent the pressure on and state of ecosystems, these two components interact with each other and jointly impact ESs. However, there is a paucity of studies linking ER, EH, and ESs to decipher their intrinsic impact mechanisms. Here, we spatially quantified the provisioning, regulating, and cultural ecosystem services of the Huaihe River Basin using the InVEST and maximum entropy models. We then explored the impact levels and paths of ER elements (natural hazard risk, human activity risk, and landscape pattern risk) and EH elements (vigor, organization, and resilience) on different types of ESs using the boosted regression tree algorithm and the partial least squares path model. Results showed that there was significant spatial heterogeneity in the provisioning, regulating, and cultural services of the Huaihe River Basin in 2020, all of which were classified into overall low grades. The paths of action among the regional ecological security features encompassed ER→ESs and ER→EH→ESs. Although vigor was a major direct positive contributor to provisioning service, resilience exhibited a greater direct impact with the relative importance of 32.79%. Resilience was also the greatest direct positive contributor to regulating service with the relative importance of 70.52%, followed by human activity risk exhibiting an indirect inhibitory effect. Human activity risk had the greatest direct positive effect and low indirect negative effect on cultural service, with the relative importance of 55.40%. Our findings are helpful to enhance the understanding of intrinsic relationships among ER, EH, and ESs, and provide scientific evidence for regional ecosystem management and decision making.

Deepening the understanding of thermal comfort conditions of urban and rural residents is important for improving the outdoor thermal environment. Based on ERA5-Land reanalysis data, this study quantifies the thermal comfort along the urban-rural gradient (urban core-urban expansion-rural area) in 101 large cities in China during the summers from 2000 to 2020 by taking physiological equivalent temperature (PET) as the evaluation index, and explores the spatiotemporal characteristics of thermal comfort and its drivers along different gradients using the Sen's slope estimation, Mann-Kendall significance test and geodetector model. The results show that: (1) The average PET in the core areas (29.89 ℃) of case cities is slightly higher than that in the expansion areas (29.86 ℃) and much higher than that in the rural areas (28.94 ℃), and the cities with higher PET in each gradient are mainly located in the Beijing-Tianjin-Hebei region and the middle reaches of the Yangtze River. (2) PET shows an increasing trend from 2000 to 2020, with an increasing rate of 0.24℃/10a in the core and expansion areas, and 0.22 ℃/10a in the rural areas. (3) Natural factors dominated by vegetation coverage and socioeconomic factors dominated by population density are key determinants of PET in the core and rural areas, respectively, while the drivers of PET in the expansion areas are unstable, with vegetation and impervious surface coverage playing an increasing role. As PET rises, the population exposed to uncomfortable environments increases, and this state of affairs poses new challenges for addressing thermal environmental issues. In the future, more studies on the thermal environment in urban and rural areas need to be conducted to provide a more comprehensive reference for the development of thermal adaptation strategies.

To achieve sustainable economic development and promote the comprehensive green transformation of the economy and society, it is necessary to improve ecological welfare performance. This study constructed a method of quantitatively evaluating ecological welfare performance in China based on residents' welfare and ecological consumption. On this basis, the ST-LMDI model was used for spatial and temporal decomposition of the ecological welfare performance of provincial-level regions and economic zones in China, thus expanding the current research on the decomposition of the driving factors of ecological welfare performance. The results of the study were as follows. First, the trend for China's ecological welfare performance from 2001 to 2020 was first increasing and then decreasing, with significant regional differences. Additionally, because of their advantages in socioeconomic structure and livelihood-based fiscal expenditures, the coastal regions had a higher ecological welfare performance and also showed spatial spillover effects. Second, the six factors of social benefits, economic benefits, population dispersion, population density in built-up areas, scale of urbanization, and ecological sustainability were introduced to explore their driving roles on ecological welfare performance. The findings showed that the spatial and temporal decomposition results were significantly different. The temporal decomposition results proved that economic benefits and scale of urbanization were the main factors promoting ecological welfare performance, whereas population dispersion inhibited growth of ecological welfare performance. However, the spatial decomposition indicated that the drivers that determine above-average ecological welfare in each provincial-level region showed regional differences and dynamic changes in different periods. The combination of spatial and temporal decomposition and the relationships among economic growth, ecological conservation, and enhancement of residents' welfare are comprehensively helpful to provide reference for local governments to formulate and implement differentiated policies.