Spatiotemporal variation of agroecosystem service trade-offs and its driving factors across different climate zones

Spatiotemporal characteristics of the trade-off among ecosystem services and its mechanism have been extensively studied. However, studies on the difference in spatiotemporal variation of ecosystem services trade-offs in various climate zones under climate change are limited. This study aims to explore the spatiotemporal characteristics and driving factors of trade-offs between crop production and soil conservation in different climate zones by employing a case study in various climate zones of the Shaanxi Province. We adopted statistical and GIS-based spatial analyses to explore the spatiotemporal characteristics of the trade-off and used gradient boosting decision tree to quantify the relative contribution of driving factors. Results showed that trade-off between crop production and soil conservation in a middle temperate zone (0.09) is significantly lower than in a warm temperate zone (0.18) and a subtropical zone (0.21). The trade-off clearly exhibits an upward trend from 1995 to 2018 in all climate zones. However, the increasing trend gradually weakened from the middle and warm temperate zones to the subtropical zone. Moreover, changes in the trade-off are spatially heterogeneous in all climate zones. Anthropogenic activities have larger relative contribution (62.27%-71.67%) to the trade-off than environmental factors in all climate zones. Climate zone type has an insignificant effect on the relative contributions of anthropogenic activities, whereas the relative contributions of most environmental factors are significantly different in various climate zones. Fertilization (relative contribution, 26.58%-37.66%), GDP per land area (relative contribution, 8.50%-20.49%), and population density (relative contribution, 9.77%-16.11%) are the most important anthropogenic driving factors in all climate zones. The environmental factors with greatest relative contribution in the middle temperate, warm temperate, and subtropical zones are accumulated temperature (13.40%), precipitation (26.64%), and accumulated temperature (9.63%), respectively. Thus, differences of spatiotemporal characteristics and driving factors of ecosystem services trade-off must be considered in the formulation of targeted polices for agroecosystem management in different climate zones.