Land consolidation of dryland-to-paddy conversion in China: Analysis of spatial patterns, impacts on cropland ecosystem services, and adaptive management strategies

Irrigation agriculture has become integral to global food production because it drastically improves productivity. Land use pattern conversion significantly influences cropland water use, the soil environment, management practices, and ecosystem services (ESs). Studies on adaptive management strategies of land consolidation of dryland-to-paddy conversion (LC-DtPC) and their effects on ESs are scarce. Therefore, this study analyzed the evolutionary spatial pattern characteristics of LC-DtPC in China over the past 20 years, assessed the overall ESs gains or losses in the LC-DtPC areas, simulated the spatial patterns of LC-DtPC under different scenarios, and explored the adaptive management strategies of LC-DtPC. The results revealed that in the past 20 years, the LCDtPC area reached 129,700 km2, accounting for 7.31% of the cultivated land area in 2020, was concentrated in China's southern and eastern regions, especially the Northeast Plain, Sichuan Basin, and surrounding areas. In the LC-DtPC zones, there were significant tradeoffs and synergistic relationships between the ESs. The food supply, water yield, and soil conservation services were promoted, while the carbon sequestration services were inhibited. Specifically, the former increased by 3787.55 x 104 t, 1329.55 x 104 m3, and 141.69 x 104 t respectively, while the latter decreased by 814.39 x 104 t. While the simulated spatial patterns of LC-DtPC varied under different scenarios, they were always concentrated in China's northeastern and southern regions. The balanced development scenario of agricultural production and ecological protection has the best long-term ecological effect, with differentiated adaptive management strategies for LC-DtPC (planning, implementing, monitoring, and evaluating). This study will fill a gap in ecosystem services of LC-DtPC, the results are instrumental in the sustainable utilization of cropland resources and regional sustainable development.