Ecological corridors play a key role in promoting the flow of ecological processes, guaranteeing ecological function services and maintaining biodiversity. Based on ecological sensitivity and ecological service values, ecological corridors in typical karst areas of Ningyuan County were constructed to lay the foundation for ecological environmental protection and land development and utilization in the county. Based on the current land use situation in 2020, the ecological source sites were identified by the combined results of ecological sensitivity evaluation and ecosystem service value analysis, and then potential corridors were generated based on the minimum cumulative resistance model (MCR) and the minimum cost path method, and key corridors were identified by the gravity model. The results show that (1) the areas exhibiting strong sensitivity are concentrated within regions characterized by better ecological environment quality; the ecosystem service value and ecological sensitivity have a similar distribution pattern, and those with high ecological value are mainly distributed in areas with better habitat quality such as woodlands and along water systems. (2) The total area of ecological source land in Ningyuan County is 879.14 km², accounting for 35.15% of the county area, mainly distributed in the south and north of the county. (3) There are nine ecological corridors in Ningyuan County, which are radially distributed in a spider-web manner, five important ecological corridors and four general ecological corridors, with total lengths of 96 km and 120.87 km, respectively.

Based on the data regarding the rural population and cultivated land at the county level in Guangdong Province in 2000, 2010 and 2020, this paper analyzes the changes in rural population and cultivated land area at the county level and their spatio-temporal coupling characteristics based on GIS technology and model methods such as the elastic coefficient, and reveals the transformation process of the rural “man–land” relationship in Guangdong Province. The results show that the rural population of Guangdong Province shows a continuous growth trend, and the cultivated land area and per capita cultivated land area show a trend of continuous reduction. From 2000 to 2010, the rural population grew by 1.37% annually, while the cultivated land area and per capita cultivated land area decreased by 0.09% and 1.28% annually, respectively. From 2010 to 2020, the rural population grew by 0.07% annually, while the cultivated land area and per capita cultivated land area decreased by 1.09% and 1.15% annually, respectively. The overall coupling type of rural population and cultivated land change in Guangdong Province presents a trend of mainly maladjusted types and gradually changing to coordinated types. From 2000 to 2010, 70.64% of the counties displayed maladjusted development types. From 2010 to 2020, the number of counties with maladjusted development types decreased, while the proportion of coordinated types increased. The natural environment, economic development level and governmental decision-making behaviors were all driving factors of coupled development of rural population and cultivated land, and the driving mechanisms of different factors have clear spatial differences in different regions of Guangdong Province. The governments and relevant departments should stick to the red line of cultivated protection, make intensive use of cultivated land and improve the livelihoods of farmers. Moreover, the Pearl River Delta, eastern Guangdong, western Guangdong and northern Guangdong should improve the cooperation mechanism for rural revitalization. The study is conducive to providing a scientific basis for rural population and cultivated land utilization management, rural revitalization and new rural construction, and promoting urban–rural integration development under the new situation.