The urban heat island (UHI) environment is closely related to the daily life of residents, and the impact of UHI is further expanding in the era of rapid urbanization, which is particularly obvious in the Beijing-Tianjin-Hebei urban agglomeration and Guangdong-Hong Kong-Macao Greater Bay Area (GBA). To explore the connection between UHI and urban expansion, this study takes GBA as the study area, based on Google Earth Engine platform and Landsat satellite data. The urban-rural temperature difference method was used to analyze the heat island zoning in the GBA from 2000 to 2020, and the direction and type of urban expansion in the GBA were investigated by standard deviation ellipse and LEI, to explore the link between the type of urban expansion and the heat island region through geospatial analysis methods. The results of the study show that: (1) The proportion of the area of strong and extreme heat islands in the GBA was 37.64% in 2000; 38.61% in 2005; 47.07% in 2010; 55.76% in 2015; and finally 59.69% in 2020. The proportion of the area of heat island regions in the period from 2000 to 2020 showed an overall increasing trend, with the largest increase in heat island regions in the period from 2015 to 2020. (2) The intensity of urban expansion in the GBA is 32% in both 2000–2005 and 2005–2010, which is significantly higher than the 9% in 2010–2015, and then increases to 24 per cent in 2015–2020. The speed of movement of urban centroids decreases in 2000–2015 and increases in 2015–2020. The direction of urban expansion in the first 5 years is dominated by the northeast, and the direction of urban expansion in the latter 15 years is generally dominated by the southwest, and the type of urban expansion is dominated by the fringe type, with the enclave type of expansion accounting for a smaller proportion. (3) Pearson correlation analysis further confirms that there is a significant positive correlation between urban sprawl and the urban heat island effect, with a correlation coefficient of 0.78 and a p-value of 0.041. There is a high degree of spatial consistency between the distribution of built-up urban areas and the distribution of heat island areas in GBA, and the direction of the evolution of the urban heat island areas is the same as the direction of the evolution of the built-up urban areas in general, and the thermal response of the marginal expansion to the ground surface temperature is stronger than that of enclave expansion. The thermal response to the surface temperature is stronger than that of the enclave type of expansion.

Forests are composed of landscape spatial units (patches) of different sizes, shapes, and characteristics. The forest landscape pattern and its trends are closely related to resistance to disturbance, restoration, stability, and the biodiversity of the forest landscape and directly influence the benefits and sustainable exploitation of forest landscape resources. Therefore, forest landscape patterns and the driving forces have increasingly attracted the attention of researchers. The present study analyzed the spatial and temporal dynamics of woodland landscape patterns in typical hilly mountainous areas in southern China using ArcGIS, landscape pattern index, and morphological spatial pattern analysis. Meanwhile, a logistic regression model was used to analyze the drivers of woodland change in Anyuan County from three aspects: natural, geographic location, and socio-economic conditions. The total area of woodland decreased during the 10-year study period, with a net decrease of 4959.27 ha, mainly due to conversion into cultivated land, garden land, and construction land. Patch density, edge density, and aggregation index of woodlands increased over time, indicating enhanced fragmentation, stable and complex patch edges, and increased patch connectivity. Conversely, the highest patch index values exhibited decreasing trends, indicating decreases in the dominant patch type. Morphological spatial pattern analysis results showed that the core area was dominant and the islet area increased over time, which also indicates enhanced fragmentation. Forest landscape change is the result of environmental change, ecological processes, and human disturbance, with geographical location and social economy having greater influences on forest landscape change. Human activities such as navel orange cultivation, returning cultivated land to forest, and land occupation for construction were the major factors driving woodland change. The results provide reference that could facilitate forest management and sustainable forest resource utilization.

With China’s urbanization process and changes in rural family structures, the abandonment of farmland in scattered villages within hilly mountainous regions is becoming an increasingly serious issue, restricting the improvement of land use efficiency. This study analyzes the basic characteristics and variations in abandoned farmland by conducting surveys and interviews with peasants in a scattered village in southern China. Using the Heckman two-stage model, we perform empirical analysis on the factors influencing farmland abandonment, addressing potential sample selection bias. The findings show the following: peasants with better health and higher education levels are more likely to transition to non-agricultural occupations which contributes to an increased abandonment of farmland. However, larger and more integrated land parcels, along with favorable farming conditions, help reduce abandonment. Additionally, rural land transfer and agricultural subsidies are important factors that enhance farmland utilization and mitigate abandonment. These results provide a reference for addressing the abandonment of farmland and improving both the farming environment and social policies in rural villages.

Non-grain production of cultivated land (NGPCL) threatened food security. Therefore, scholars have begun study this area in China and other countries, but most of the studies have focused on large scales, and few studies have focused on plot scale analysis. This study presents an analytical framework to shed light on the causes of NGPCL in the hilly mountainous regions of southern China. First, we categorized NGPCL into severe damage class and slight damage class according to the degree of damage of NGPCL to cultivated soils and the difficulty of restoring food production capacity. Then, we revealed the characteristics of spatial differentiation and causes of NGPCL in the southern hilly areas by using methods such as binary logistic regression model and spatial correlation analysis. Finally, the results in the study showed that: (1) the overall NGPCL areal in 2020 was 11288.46 hm², accounts for 38.14%, of which the areas of NGPCL in the minor damage class and the serious damage class were 27.32% and 10.82%, respectively. (2) The spatial differentiation of NGPCL was obvious, which showed a clustered distribution pattern, with NGPCLs of the minor damage class clustered at high values in the topographically flat areas of the east-central zone, and NGPCLs of the severe damage class clustered at high values in the vicinity of the central urban area. (3) The levels of NGPCL for each type were significantly correlated with the three dimensions of natural, locational, and socio-economic factors, while topography, cultivated land infrastructure conditions and the degree of centralized and contiguous cultivated land were the important drivers of spatial differentiation of NGPCL. This paper reveals the distribution and influencing factors of NGPCL at the plot scale, that can provide theoretical reference and categorized governance suggestions for NGPCL governance in similar regions in China and even in the world.