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Due to the joint influence of human activities and climate change, lakes experience significant shrinkage or expansion, posing enormous challenges for water resource management and the ecological balance of lake ecosystems. As an important region abundant in water resources in China, the balance of water resources in the middle and lower Yangtze River Basin (MLY) is crucial for region sustainable development. However, to date, few studies have quantitatively analysed the lake area during heat waves in the MLY. To fill this gap, this study selected the summer of 2022, which encountered unprecedented heat waves, to analyse the changes of lake area in the MLY. Specifically, Sentinel-1 images were used as data sources, and the Random Forest (RF) model was applied to extract the monthly area of 62 lakes (area >10 km2) in the MLY from 2019 to 2022. The results showed that: (1) Compared to the Support Vector Machine (SVM) model and the Otsu method, the RF model had the highest accuracy, with its accuracy and Kappa coefficient in the testing samples of 97.14% and 0.94, respectively. During the period from June to September in 2022, the total area of 62 lakes decreased by 3475.50 km2. (2) Compared to the same period in the summer of 2019–2021, 23 lakes (37.10%) were observed to experience shrinkage. Among them, the area of Poyang Lake and Dongting Lake decreased to the level of the previous winter dry seasons in August 2022. (3) Temperature was the most important meteorological factor that caused changes in the lake area in the MLY, compared to precipitation, evaporation, and runoff. This research can help understand the impact of climate change on lakes and provide references for decision-making in the MLY to formulate the strategies of water resource management under the changing climate. [ABSTRACT FROM AUTHOR]

The construction of the ecological security pattern (ESP) and ensuring its integrity are the focal points of ecological actions. However, existing evaluation frameworks lack comprehensiveness, and studies addressing temporal dimensions are limited. This study constructed a comprehensive framework to evaluate ESP and introduced a method to portray the relationship between ecological security status and landscape structure. Initially, multiple indicators were optimized to construct an ecological security index (ESI). The relationship between ESI and landscape structure was quantified. Then, fifteen spatiotemporal factors were combined using the Analytical Hierarchy Process to construct an ecological resistance layer. Finally, Circuit theory was applied to visualize trends in ESP. The findings indicated that ecological security was generally better but with a downward trend. The relationship between ESI and landscape fragmentation was mainly a tradeoff. The area of stable ecological sources was 1251.06 km2 (1996–2021). The number of minimal-cost corridors decreased continuously. Ecological sources with the highest conservation priority were the largest (1336.2 km2) in 2021. The number of pinch points was 25, 31, and 30, while ecological barriers covered 51.5, 148.74, and 139.51 km2 in 1996, 2008, and 2021, respectively. This study will serve as a valuable methodological reference and support ecological civilization projects in Fuzhou. [ABSTRACT FROM AUTHOR]

The effective refuge area is a key indicator in the study of emergency shelters. Accurately extracting the effective refuge area and analyzing the effectiveness of emergency shelters are of great significance for site selection, spatial distribution, and the evaluation of suitability. Beijing is one of only three capitals in the world located in a high-seismic-intensity zone of magnitude 8. The fast and accurate monitoring of effective refuge areas and an analysis of the effectiveness of emergency shelters are conducive to evacuation planning and disaster prevention and mitigation, and they promote the construction of a resilient city. However, the extraction of effective refuge areas in existing studies is not only a time-consuming and labor-intensive task but also has accuracy and efficiency problems, resulting in less precise validity analyses. In this paper, a remote sensing monitoring technology system for the effective refuge areas of emergency shelters is proposed based on multi-source data. Different methods were used to extract various land features, such as buildings and collapsed areas, water, dense areas of understory vegetation, and steep slope areas that cannot be evacuated, to obtain the effective refuge area at a detailed scale, in combination with the service radius of emergency shelters, the population distribution, and the actual road network, the criteria for effectiveness analysis were established for the effective open space ratio, capacity, per capita accessible effective refuge area, and population allocation gap. Taking the area within the Fifth Ring Road of Beijing as an example, the effectiveness of emergency shelters was analyzed at both the whole scale and a local scale. The results show that the effective refuge areas of different emergency shelters in Beijing vary significantly, with the smallest effective refuge area being located in Rings 2–3 and the largest one being located in Rings 4–5; between different regions, there are differences in the effectiveness. This study provides a feasible method for the fast, accurate, and detailed extraction of the effective refuge areas of emergency shelters and also provides a reference for emergency planning for disaster prevention and mitigation. [ABSTRACT FROM AUTHOR]

China's report of government–business relation (GBR) index focuses on the roles of the GBR in improving information transparency of economy and society, but ignores the GBR's potential in enhancing environmental information transparency (EIT). This research employs the data from 120 cities in 30 provinces in China to map the distribution of GBR and EIT, which basically coincides with Hu-line (population density and developed economy boundaries in China), showing the trend of high-quality performance in the eastern region of China, but low-quality performance in the central and western region of China. To study the relations of GBR, population, GDP per capita with EIT, and their influential degree on EIT, the test of Pearson correlation coefficient, ordinary least squares, and multiple linear regressions are, respectively, applied in the study. Moreover, the intra-provincial comparison is conducted to study the discrepancies of EIT within a province in different regions of China. The results show that the EIT-population relation and the EIT-GDP per capita relation both present inverted U-shaped curves, and GBR is positively related to EIT. Moreover, there are the more balance performance of EIT within the province in the eastern China, while the central and western of that is opposite. This work firstly finds the relation among GBRI, EIT, and Hu-line and extends the application of environmental Kuznets curve. Policy and managerial implications are expounded to enhance the performance of EIT and sustainability by developing the potential of GBR and better allocating resources. [ABSTRACT FROM AUTHOR]