## 1 Introduction  
Farmland is the foundation of the agricultural sector, and food security is a cornerstone of national stability [1, 2]. Since the initiation of economic reforms and opening-up, China has undergone rapid industrialization and urbanization, which has significantly increased employment opportunities and led to a sharp rise in wages in non-agricultural sectors. As a result, a substantial proportion of the rural labor force has migrated to urban areas or non-agricultural sectors [3; 4]. The resulting reduction in rural labor, coupled with the aging of the agricultural workforce and the increasing marginalization of farmland, has exacerbated the abandonment of farmland, both in extent and intensity, posing a serious threat to China's food security and agricultural stability [5; 6; 7]. This abandonment also has various impacts on biodiversity [8], soil quality, carbon cycling [9; 10], and the broader ecological environment [11]. According to the Third National Land Survey of China (conducted in 2017-2019), the total area of cultivated land stands at 127.8619 million \(\mathrm{hm}^{2}\), a decrease of 7.5231 million \(\mathrm{hm}^{2}\) compared to the results of the Second National Land Survey (conducted in 2007-2009) [12]. Consequently, research on the quantity, spatial distribution, and driving factors of abandoned farmland are essential to mitigating land abandonment, improving land use efficiency, and promoting the stable development of rural economies and societies. The concept of land abandonment refers to the condition in which farmland is left fallow or underutilized due to the decisions made by land users. These decisions are influenced by a range of factors, including natural, social, economic, and policy conditions [13]. Abandoned farmland can be classified into two main categories based on its utilization status and the duration of abandonment. The first category includes land that is not cultivated during certain seasons of the agricultural production cycle due to factors like climate conditions and farming practices. This type of land is referred to as seasonal land abandonment. The second category includes farmland that remains idle and unused for one year or more. This prolonged abandonment is typically caused by factors such as remote geographic location, poor land quality, high cultivation costs, low agricultural returns, or other socio-economic reasons that discourage farmers from continuing cultivation. This type of practice is known as permanent land abandonment [14; 15]. The extraction of the amount and spatial distribution of abandoned farmland is essential for managing land abandonment. The main methods for extracting data on abandoned farmland include sampling surveys, literature meta-analysis, and remote sensing analysis. Sample survey is a method used to assess land abandonment on a small scale, primarily through household interviews, field surveys [16; 17], or survey data from authoritative organizations to assess the extent of abandoned farmland in a given region [18; 19; 20]. This traditional approach requires substantial human and material resources, making it unsuitable for large-scale, high-precision, long-term projects [21]. Literature meta-analysis involves reviewing studies on farmland abandonment in different regions and employing meta-analytic methods to create a database that classifies different types of abandoned farmland [22]. This method can effectively assess the status of farmland abandonment on a small scale. However, the limited selection of study areas and sampling points makes it difficult to monitor the temporal and spatial changes of abandoned farmland and to carry out long-term monitoring of land abandonment [20; 23].