标题：The contribution rate of stem-leaf and root of alfalfa (Medicago sativa L.) with diverse spatial distribution patterns to sediment and runoff reduction on the Loess Plateau

作者：Chong Yao, Yan Zhuan, Yonghua Liu, Yixin Wang, Gaohan Xu, Siyuan Chen, Ming Zhu and Faqi Wu

来源出版物：Frontiers in Plant Science

DOI：10.3389/fpls.2026.1854426

出版年：2026

文献类型：Article

语种：英文

摘要：

Introduction: Herbaceous plants regulate the generation of runoff and sediment and the anti-erosion ability of soil by altering vegetation coverage and root systems, thereby influencing soil erosion. However, the variation in soil erosion reduction benefits and the contributions of stem–leaf and roots under diverse vegetation spatial distribution patterns on the Loess Plateau have not yet been understood.

Methods: In the current study, alfalfa spatial distribution patterns with vegetation coverage of 50% (T1 treatment; LS, downstream of hillslopes; MS, middle of hillslopes; US, upper of hillslopes; and SS, equidistant planting), four alfalfa spatial distribution patterns without above-ground biomass (T2 treatment), and bare soil (CK) were designed. Rainfall simulations with slope gradients of 8.75%, 17.63%,

26.80%, and 36.40% and a rainfall intensity of 90 mm h−1 were carried out on runoff plots (2 m × 1.0 m) filled with clay loam. The initial runoff generation time (RT) was recorded, and runoff sediment samples were collected.

Results: The results showed that the RT for the T1 and T2 treatments was delayed by 1.47 to 2.51 and 0.75 to 1.65 min, respectively, compared with CK. The mean runoff rate for the T1 and T2 treatments ranged from 0.18 to 1.15 and from 0.61 to 1.16 L m⁻² min⁻¹, respectively. The mean sediment rate for the T1 and T2 treatments ranged from 1.50 to 18.63 and 3.01 to 20.01 g m⁻² min⁻¹, respectively. The runoff reduction benefits (RRB) for the T1 and T2 treatments ranged from 44.20% to 84.67% and from 34.40% to 43.66%, respectively. The sediment reduction benefits (SRB) for the T1 and T2 treatments ranged from 25.01% to 86.48% and from 9.30% to 71.30%, respectively. The contribution rates of stem–leaf and root to RRB ranged from 3.87% to 30.14% and from 10.10% to 30.80%, respectively, and those for SRB ranged from 9.75% to 24.65% and from 7.28% to 37.75%, respectively. Principal component analysis indicated that the slope gradient explained the greatest variation in runoff, followed by the spatial distribution pattern and vegetation traits.

Conclusion: The research results provide references for vegetation protection and management in areas with severe soil erosion and enrich the understanding of soil erosion mechanisms.

关键词：alfalfa, rainfall simulation, soil erosion, spatial distribution pattern, vegetation component

影响因子：5.9

论文链接：https://doi.org/10.3389/fpls.2026.1854426

（地理科学学院 程建双/撰稿 崔向超/初审 闫军辉/复审 韩勇/终审）