基于CSLE模型的黄河上游龙羊峡至积石峡段流域土壤侵蚀评价

CSLE Mode-Based Assessment of the Soil Erosion Along the Longyangxia Gorge and Jishixia Gorge in the Upper Yellow River

[目的]研究黄河上游龙羊峡至积石峡段流域2017—2021年土壤侵蚀特征,揭示区内植被在防治土壤侵蚀中的贡献,进而为黄河上游流域开展植被水土保持与生态安全保护的合理实施提供科技支撑。[方法]以位于黄河上游的龙羊峡至积石峡段流域为研究区,基于CSLE模型分别以空间插值法和地图代数法,探讨了区内土壤侵蚀、各年份植被覆盖度空间分布,以及植被覆盖度时空变化空间分布特征;在此基础上,分析了区内植被有效防治土壤侵蚀过程中的减蚀作用。[结果]区内2017—2021年黄河上游龙羊峡至积石峡段流域土壤侵蚀以微度和轻度侵蚀作用为主,5个不同年份其平均土壤侵蚀模数分别为21.329,55.518,23.394,21.490,21.650 t/(km^(2)·a)。[结论]2017—2021年区内发生中度和强度侵蚀区域主要集中在极低植被覆盖度区,其中微度侵蚀区域的植被覆盖度普遍较高,结果表明区内植被能有效减少土壤侵蚀现象的发生。

[Objective]The aims are to study the soil erosion characteristics of Longyang Gorge to Jishi Gorge in the upper reaches of the Yellow River from 2017 to 2021,reveal the contribution of vegetation in soil erosion prevention and control,and provide scientific and technological support for the rational implementation of vegetation soil and water conservation and ecological security protection in the upper reaches of the Yellow River basin.[Methods]The section from Jishixia Gorge to Longyangxia Gorge of the Yellow River was chosen as the study area,and based on CSLE modes,methods of using spatial interception and map algebra were adapted to obtain soil erosion and vegetation coverage in this region and the spatial-temporary variation of the prementioned data.[Results]On these basis,the contribution of the vegetation to conserving soil was assessed,and the corresponding results showed that from 2017 to 2021,slight erosion and light erosion were the predominant erosion intensities,and the corresponding erosion moduli were 21.329,55.518,23.394,21.490,21.650 t/(km^(2)·a),respectively.[Conclusion]Additionally moderate and heavy erosion generally occurres in regions with sparse vegetation coverage,and regions suffering a slight erosion are generally characterized with high coverage,which verifies the role vegetation in reducing soil erosion.The vegetation can effectively reduce the occurrence of soil erosion.