Mapping rainfall interception for assessing ecological restoration sustainability in China

Abstract

Ecological restoration (ER) programs play an important role in local and global climate change and carbon management policy interventions. Water resource is a key criterion for assessing the sustainability of ERs. Herein, we explored the spatiotemporal patterns of rainfall interception (RI, an important component of ecosystem water budgets), and its drivers after ER implementation in China. Further, we assessed whether ERs are sustainable by analyzing the trends of RI and water supply. As expected, we found that ERs caused an increase in RI in China from 2001 to 2018 (0.64 mm yr−1, p < 0.01). Changes in the normalized difference vegetation index and leaf area index contributed to a higher change in RI compared with other drivers. The decrease in RI was mainly recorded in the Qinghai–Tibet Plateau in Southwest, northern North, and southern Central and Southern China. Conversely, an increasing trend of RI was recorded in the Loess Plateau in Northwest, Northeast, and East China. Moreover, ERs are not always unsustainable in China, especially in Northeast, East, Central and Southern, and high-latitude regions of northern North China. Even in the Loess Plateau, which was criticized by previous studies, the unsustainability occurred only in the semi-humid region. Future ERs should be prioritized in southern parts of Eastern, Central, and Southern China, and must be appropriately considered in the Northeast and high-latitude regions in North China. It should be alert to the pressures of ERs on water supply, and its demand remains vigilant in the Qinghai–Tibet Plateau and semihumid areas of the Loess Plateau. This study provides new ideas for accurately evaluating the impact of ERs on water security and the sustainability of ERs.