Delineation of a basic farmland protection zone based on spatial connectivity and comprehensive quality evaluation: A case study of Changsha City, China

摘要

The continuous reduction of farmland poses a serious threat to national food security. Delineating essential basic farmland for special protection is urgently needed in China and is an important measure to stabilize food production capacity and ensure regional food security. Currently, research on basic farmland delineation is mostly based on the evaluation of the characteristics of the farmland and lacks the integration of multiple factors such as spatial connectivity and scale constraints. Solving these issues will help improve the rationality and scientificity of basic farmland delineation. This study performed a case study of Changsha City based on land use, spatial planning, economic and social factors, natural geography, and other multi-source data. The index method and the food demand method were used to predict the scale of basic farmland protection to determine the basic farmland scale thresholds. Buffer analysis method is used to measure the spatial connectivity of farmland. This study implemented the LESA evaluation system to construct a comprehensive quality evaluation index system for farmland. Finally, based on the technical framework of basic farmland delimitation of "serial priority, quality screening, and scale constraint," the basic farmland scale was determined to be 23,104,701 ha.