Zhao Changxing, Mou Wenbo, Liu Jinrong, Li Chaonan, Lei Longju, Ta Feng, Lai Shiwei, Feng Yonglin, Zhou Ziqiang
State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
Sci Total Environ. 2024 Feb 20;912:169528. doi: 10.1016/j.scitotenv.2023.169528. Epub 2023 Dec 21.
Soil erosion leads to soil degradation and depletion of land resources, posing a significant threat to industrial production and ecological sustainability. In high-altitude regions, rill erosion is the main form of soil erosion in mining areas, however, our understanding of morphology and developmental characteristics of rills and the mechanisms influencing them remains limited. In this study, data were collected from 96 rill plots across two gold mines in the eastern Tibetan Plateau according to vegetation restoration modes (natural restoration (CK) and planted with Elymus dahuricus (ED), Medicago sativa (MS), and multi-plant mixed (Avena fatua L. + Elymus dahuricus + Medicago sativa + Oxytropis coerulea, MM)) and restoration periods (1 year, 3 years, 4 years, and 6 years). We investigated the variations of 7 indicators that can reveal rill morphological and developmental characteristics across different restoration modes and restoration periods, and utilized a partial least squares structural equation model (PLS-SEM) to analyze the effects of 15 indicators from topography, soil, and vegetation on rill erosion modulus (REM). The results indicated that artificial vegetation restoration effectively restrained rill development, notably by decreasing the frequency of wider (>15 cm) and deeper (>10 cm) rills when compared to CK plots. Planting MM and ED exhibited greater efficacy in controlling rill erosion than planting MS. However, the effectiveness of planting ED in controlling rill erosion gradually weakened with time, while MM consistently maintained a strong inhibitory effect. Topographic features, soil texture, and vegetation significantly influenced the REM through direct or indirect effects. Plant root functional traits were the main driving factors in reducing REM, affecting not only REM directly but also influencing vegetation-induced soil properties to indirectly effect REM.
土壤侵蚀导致土壤退化和土地资源枯竭，对工业生产和生态可持续性构成重大威胁。在高海拔地区，细沟侵蚀是矿区土壤侵蚀的主要形式，然而，我们对细沟的形态和发育特征及其影响机制的了解仍然有限。本研究根据植被恢复模式（自然恢复（CK）、种植披碱草（ED）、紫花苜蓿（MS）和多植物混合（野燕麦+披碱草+紫花苜蓿+蓝花棘豆，MM））和恢复时期（1年、3年、4年和6年），从青藏高原东部的两个金矿的96个细沟样地收集数据。我们调查了7个能够揭示不同恢复模式和恢复时期细沟形态和发育特征的指标的变化，并利用偏最小二乘结构方程模型（PLS-SEM）分析了地形、土壤和植被的15个指标对细沟侵蚀模数（REM）的影响。结果表明，人工植被恢复有效地抑制了细沟发育，特别是与CK样地相比，减少了较宽（>15厘米）和较深（>10厘米）细沟的频率。种植MM和ED在控制细沟侵蚀方面比种植MS表现出更大的效果。然而，种植ED控制细沟侵蚀的有效性随时间逐渐减弱，而MM始终保持较强的抑制作用。地形特征、土壤质地和植被通过直接或间接影响显著影响REM。植物根系功能性状是降低REM的主要驱动因素，不仅直接影响REM，还通过影响植被诱导的土壤性质间接影响REM。
