The mechanisms and spatial-temporal effects of farmland spatial transition on agricultural carbon emission: based on 2018 counties in China

Agricultural carbon emission reduction is an important issue in environmental protection and development in China and the world. The farmland spatial transition is an important path for agricultural modernization in developing countries such as China. How can farmland spatial transition promote agricultural carbon emission reduction? This paper aims to explore the mechanisms and spatial-temporal effects of farmland spatial transition on agricultural carbon emission density. To study the mechanisms and effects, we establish the random effect model, the threshold model, and the GTWR model with 2018 counties in China from 2000 to 2020. The research shows the farmland spatial transition mainly promotes agricultural carbon emission reduction through the interaction mechanism of large-scale production and specialized production, intermediary, and threshold mechanisms of agricultural technology. The result also shows that specialized farmland management is the main driving force of agricultural carbon emission reduction for farmland spatial transition. Moreover, the impact of farmland spatial transition on agricultural carbon emission reduction has significant spatial and temporal differences. The most significant regions are located in the middle and lower reaches of the Yangtze River plain, while the least are the north and southwest. Besides, the impact of the farmland spatial transition on agricultural carbon emissions reduction has a “V” shape over time, indicating China’s agricultural carbon emission reduction is facing enormous economic and social development challenges. Our research reveals the various mechanisms and spatial-temporal effects of the transition of farmland spatial morphology on agricultural carbon emission with an evaluation framework, which is crucial to low-carbon agriculture with proper farmland use.