Response of cultivated land quality to landscape pattern changes at the watershed scale

High-quality cultivated land can enhance soil fertility and strengthen crop resilience, promoting sustainable agricultural development and ensuring national food security. In this study, the indices of cultivated land landscape patterns were correlated with cultivated land quality at the watershed scale using topographic factor extraction, the landscape pattern index method, spatial autocorrelation analysis and Pearson's correlation coefficient. The response of the quality of cultivated land to landscape pattern changes was evaluated for different landform types using data from 22 years of Landsat remote sensing image data(February 23-24), and data about the quality of arable land resources in the Chaohu Lake Basin. The results showed that there were positive correlations between the landscape pattern indices of the different types of landforms in the catchment area. The comprehensive cultural landscape index was most strongly aggregated in low-elevation plain areas and most weakly aggregated in plateau areas. The patch density index was high around water bodies in the Chaohu Lake Basin, where the soil-layer thickness (>60 cm), soil organic matter content, and soil pH were all suitable for cultivation, and paddy fields were more concentrated than in other areas of the basin. In the most comprehensive index of cultivated land landscape patterns, low-elevation hilly areas and plateau regions showed the highest proportions of low outliers (37.20 % and 47.56 % respectively). The elevated proportion of low outliers indicates poor landscape connectivity and more severe landscape fragmentation in these areas compared to other regions, which could lead to cultivated land being divided into smaller patches, increasing risks of soil erosion, thus necessitating enhanced protection measures.