Can the transition of multiple cropping systems affect the cropland change?

Intensification of cropland can achieve food security by increasing agricultural production pre-unit yield, thereby slowing down cropland expansion. However, it is also possible to accelerate the cropland expansion due to the increasing net benefits of cropland. The transition of multiple cropping system (MCS) caused by climate change is an important strategy for cropland intensification, its impact on cropland changes needs further in-depth discussion. This research aims to address the following two questions: (1) The transition patterns of the MCS in China against the background of climate change; (2) The impact of the MCS's transition on the change rate of cropland and grain production capacity. Based on meteorological observation data, the Global Agro-Ecological Zones (GAEZ) model is utilized to map the China's MCS to analyze the temporal and spatial variation patterns of MCS under the comprehensive influence of various meteorological factors. On this basis, we investigate the change of cropland area and grain production capacity under the transition of MCS. The results indicate that in the past 20 years, the increase of cropping intensity in China has led to 0.42Mha expansion in the multiple cropping area. Temporally, the probability of maintaining the original cropping system (2000) in 2020 was greater than the probability of transiting (83% > 17%). These transitions occurred more frequently between cropping systems with small gradation differences, and the probability of cross-gradation changes decreased with increasing cropping intensity. Spatially, the MCS exhibited a decreasing trend with increasing distance from the coastline. Although regardless of whether the MCS transiting or maintaining, the cropland area would reduce, the increase in cropping intensity would reduce the cropland area more than the decrease (6.48% > 2.66%). Moreover, we found that the decreased cropping intensity was beneficial to slow down the cropland reduction (4.35%; 2.93%; 5.95% > 2.66%), while increased cropping intensity accelerated the cropland reduction (1.56%; 4.35%; 2.93%; 5.95% < 6.48%). This result was further validated by grid-based statistical regression results (p < 0.05). In regions where the MCS transited, 96% of the cropland decrease was occupied by construction land, and 76% of the cropland expansion was due to the conversion of grassland. Among them, when the cropping intensity increased, although the cropland area reduced even more, the grain production capacity would actually increase by 40.29%, and when the planting intensity decreased, the grain production capacity would decrease by 10.55%. Increasing the cropping intensity of cropland through multiple cropping can increase the comprehensive grain yield under the condition of limited cropland resources. This strategy holds significant promise for bolstering China's food security and fostering sustainable agricultural development.