黄河上游巨型滑坡区植被分布及其根系力学强度特征  

Vegetation distribution patterns and root mechanical properties of selected plant species on the Xijitan giant landslide in the upper reaches of the Yellow River

作　　者：赵吉美 胡夏嵩[3] 付江涛 刘昌义[3] 邢光延 杨馥铖 张培豪 周喆 ZHAO Ji-mei;HU Xia-song;FU Jiang-tao;LIU Chang-yi;XING Guang-yan;YANG Fu-cheng;ZHANG Pei-hao;ZHOU Zhe(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China;School of Mechanical Engineering,Qinghai University,Xining 810016,China;Department of Geological Engineering,Qinghai University,Xining 810016,China;Academy of Agriculture and Forestry Sciences,Qinghai University,Xining 810016,China)

机构地区：[1]青海大学农牧学院,青海西宁810016 [2]青海大学机械工程学院,青海西宁810016 [3]青海大学地质工程系,青海西宁810016 [4]青海大学农林科学院,青海西宁810016

出　　处：《草业学报》2024年第1期33-49,共17页Acta Prataculturae Sinica

基　　金：国家自然科学基金资助项目(42041006);第二次青藏高原综合科学考察研究项目(2019QZKK0905);青海省自然科学基金项目(2020-ZJ-906)资助。

摘　　要：为研究黄河上游巨型滑坡区植被分布类型及其根系力学强度特征,以位于黄河上游席芨滩巨型滑坡区为研究区,通过野外植被样方调查、制取根系和土体试样以及室内开展单根拉伸试验等方法,探讨了区内3种优势草本植物醉马草、异针茅、冷地早熟禾的单根抗拉力学特征,以及植物生长区土体营养元素特征对植物分布的影响。结果表明:席芨滩滑坡区以草本植物为主,灌木零星分布,物种数呈“驼峰状分布”;通过采用冗余分析得到,草本植物生长区土壤含水量(P<0.01,F=12.7)、pH值(P<0.05,F=8.0)和全氮(P<0.05,F=4.5)对植物群落生长和分布特征影响较为显著。进一步研究表明,同种植物生长位置不同,则其单根抗拉力学强度亦不同,而相同位置处的不同种植物,相应地其单根力学强度亦表现出不同的特征。这种特征表现在分布于滑坡中部的冷地早熟禾的平均单根抗拉力和平均抗拉强度均显著高于生长在滑坡前缘和后壁位置的;分布在滑坡中部位置处的3种优势草本植物,其平均单根抗拉力和平均单根抗拉强度由大至小依次为异针茅(9.10 N,80.29 MPa)、冷地早熟禾(7.51 N,49.78 MPa)、醉马草(6.69 N,34.82 MPa)。本研究结果可为科学防治席芨滩滑坡分布区边坡水土流失、浅层滑坡等坡面水土灾害提供理论依据和实际指导。This research investigated the distribution pattern of vegetation and the root mechanical properties(tensile resistance,tensile strength)of selected plant species(Achnatherum inebrians,Stipa aliena and Poa crymophila)on the Xijitan giant landslide in the upper reaches of the Yellow River,and also the influence of soil nutrient status on field distribution of these species.Methodology included quadrat investigation of species distribution,root system extraction,soil sampling of 3-10 cm soil depth,and single root tensile tests.It was found that herbs were the main species sparsely mingled with shrubs.Based on redundancy analysis,soil water content(P<0.01,F=12.7),pH(P<0.05,F=8.0)and total nitrogen(P<0.05,F=4.5)were the main factors affecting the distribution of the plant communities in this area.Furthermore,tensile strength of roots of the same species was different in different growth positions,and tensile strength of roots of different species in the same position also differed.Average tensile strength and tensile resistance of single root of P.crymophila plants located in the middle of the landslide were significantly higher than those growing in the front and rear edge of the landslide.Average tensile strength and resistance of single root of the three dominant herbs located in the middle of the landslide were S.aliena(9.10 N,80.29 MPa),P.crymophila(7.51 N,49.78 MPa),and A.inebrians(6.69 N,34.82 MPa),respectively.The results provide a theoretical basis and practical guidance for planting to control slope soil and water loss in shallow landslides.

关 键 词：黄河上游 巨型滑坡 席芨滩滑坡 植被分布 单根抗拉力 单根抗拉强度 

分 类 号：S157[农业科学—土壤学]