Remediation performance of land leveling projects on cultivated land fragmentation under micro-topographic differences

China's expansive mountainous and hilly regions, shaped by varied topography, have led to widespread fragmentation of cultivated land, posing challenges to mechanized and large-scale agriculture. Land Leveling Projects (LLPs) have been widely adopted to address this issue. However, their effectiveness, particularly across different micro-topographical conditions, has not been systematically evaluated. This study examines the performance of LLPs in reducing Cultivated Land Fragmentation (CLF) using 16 land consolidation projects in the mountainous and hilly areas of Chongqing as case studies. This study constructs a tripartite analytical framework of “geomorphological type - project intensity - remediation performance”. Taking typical mountainous and hilly areas of Chongqing as a case study, it selects 16 implemented LLPs under different micro-geomorphological conditions as samples to comprehensively investigate the performance of LLPs in remediating CLF. The results showed that: (1) Various types of LLPs, including Strip Field Remediation Projects (SFRP), Terrace Remediation Projects (TRP), Slope-to-Terrace Projects (STP), Slope-to-Slow Projects (SSP), Field Merging Projects (FMP), and Mesa Reconstruction Projects (MRP), can all reduce CLF to some degree. (2) Micro-topographical conditions significantly influence LLPs performance. The Gentle Hilly and Flat Dam Area (GHFDA) showed the highest remediation effectiveness, followed by the Low Hill Area (LHA), Hilly and Wide Valley Area (HWVA), and Middle-Low Hillside Area (MLHA). (3) Complex terrain increases the degree of land fragmentation and the investment required for LLPs, without corresponding improvements in remediation outcomes. (4) Given limited financial resources, priority should be given to areas with high remediation potential and adaptability, such as GHFDA and LHA. These regions are more suitable for reducing fragmentation and promoting large-scale cultivation. In contrast, large-scale LLPs are less appropriate for MLHA; instead, efforts should focus on improving field access, irrigation systems, and basic infrastructure to enhance production and living conditions. This study provides a foundation for evaluating the performance of LLPs and supports more targeted, effective land management strategies in complex terrains. • Various Land Leveling Projects (LLPs) reduce Cultivated Land Fragmentation (CLF). • LLPs obviously improve area fragmentation, but shape/spatial remediation is limited. • Landform complexity increases LLPs' costs, but CLF remediation doesn't rise equally. • LLPs' CLF reduction efficiency by micro-geomorphic type: GHFDA > LHA > HWVA > MLHA. • Prioritize LLPs in GHFDA/LHA; avoid large-scale LLPs in MLHA.