Identifying cumulative transition effects of large-scale vegetation restoration on climate and hydrology via a dynamically separating framework

Abstract

Vegetation restoration is an important approach to improve ecosystems and address climate warming. However, there is significant debate regarding climate and hydrological impacts of large-scale vegetation restoration. This study proposes a framework for dynamically separating the cumulative climate and hydrological effects of vegetation restoration, offering a perspective on the seasonal and regional variations in these effects. The framework applies WRF-NoahMP land-atmosphere coupled model with various surface parameters to distinguish the seasonal climate and hydrological effects of the Grain for Green Program as well as the inconsistency in climate and hydrological effects between important grassland restoration and afforestation regions. The Middle Yellow River Basin, a region severely impacted by large-scale vegetation restoration, was selected to demonstrate the proposed approach. The results indicate that seasonal variations in albedo, fraction of vegetation cover, and leaf area index contribute to distinct seasonal patterns in the climate and hydrological effects of vegetation restoration in the study region, with maximum effects observed in summer. A significant shift in the cumulative climate and hydrological effects occurred around 2010 during 2001-2020. Compared to the afforestation region, the grassland restoration region showed significantly reduced land surface temperature and soil moisture, and enhanced evaporation and precipitation recycling (p < 0.05). Our study contributes to an efficient method for distinguishing the seasonal cumulative climate and hydrological effects of vegetation restoration, as well as the inconsistency in climate and hydrological effects resulting from afforestation and grassland restoration regions, providing insights to better implement vegetation restoration initiatives.