Biophysical feedback from earlier leaf-out enhances nonerosive precipitation in China
Zhuoran Yan, Jiuchun Yang, Han Zhang, Wenbo Li, Yeqiao Wang, Huanjun Liu, Lingxue Yu
Abstract
Abstract Earlier leaf-out enhances spring moisture exchange between land and atmosphere. However, its impact on precipitation intensity remains unclear, hampering dynamic monitoring on water erosion. Here we combined remote sensing, reanalysis data, and coupled land-atmosphere model to address this knowledge gap. Results observed an increasing trend in spring precipitation accompanied by earlier leaf-out across temperate China. The simulations isolated the phenological impacts and attributed it to the enhancement of nonerosive precipitation. The mid-temperate semi-humid region exhibited the largest increase (3.03 ± 3.66 mm) in response to 14-days leaf-out advancement. Conversely, erosive precipitation declined in sparsely vegetated areas (<50% cover), sharpening the heterogeneity of moisture gradient. Elevated convective available potential energy promoted more frequent precipitation, inhibiting the deep moisture accumulation required for erosive downpours. Simulated erosive precipitation also declined in temperate summer and autumn. Findings highlight vegetation’s role in precipitation redistribution beyond surface interception, requiring conservation planning to consider bidirectional vegetation-climate feedback.