金沙江干热河谷乡土草本植物根系固土能力原位测定  

In situ measurementon the capability offixing soil of local herbaceousroots in dry-hot valley of Jinsha River

作　　者：段青松[1,2] 何丙辉[2] 余建新[1] 张川[1] 字淑慧[3] 杨旸[4] 李亚伟[4] 

机构地区：[1]云南农业大学国土资源科学技术工程研究中心,云南昆明650201 [2]西南大学资源环境学院,三峡库区生态环境教育部重点实验室,重庆400715 [3]云南农业大学农学与生物技术学院,云南昆明650201 [4]云南农业大学,水利水电学院,云南昆明650201

出　　处：《云南大学学报（自然科学版）》2015年第5期779-785,共7页Journal of Yunnan University(Natural Sciences Edition)

基　　金：“十二五”国家科技支撑计划(2011BAD04B01)

摘　　要：研究采用野外原位剪切试验的方法,对金沙江干热河谷分布较广的扭黄茅(Heteropogon contortus)、莎草(Eulaliopsis binata)、芸香草(Cymbopogon distans)、旱茅(Schizachyrium delavayi)等4种乡土草本植物的根系固土能力进行了研究.结果表明:1草本植物根系能提高土壤的抗剪强度,起到固土作用.在受试的4种草本植物中旱茅根系提高土壤的抗剪能力最强达72.5%,扭黄茅最低为2.8%;2在特殊情况下,根系会降低土壤的抗剪强度,起到疏松土壤的作用.在研究中,扭黄茅根系第1样方出现了抗剪强度低于裸土样方的情况;3植物根系在提高土壤抗剪强度的同时,也提高了土壤的破坏位移.在受试的4种草本植物中,破坏位移最大是莎草、最小是芸香草,分别比裸土样方提高了109.4%、32.7%,草本植物根系提高土壤剪切破坏位移的幅度比提高抗剪强度的幅度大;4在受试的4种草本植物中,旱茅固土能力最强,又是优良的牧草,在金沙江干热河谷生态恢复、边坡防护、植物篱等生态工程中可作为优先选用的植物.The fixing soil capability of roots of 4 local herbaceous herbs, Heteropogon contortus, Eulaliopsis binata, Cymbopogon distans, Schizachyrium delavayi, which are widely distributed in dry-hot valley of Jinsha River,was studied by in situ measurement.The results showed that： （1） Roots of the 4 local herbaceous herbs enhanced anti-shearing strength of soil and fixed soil.Among the selected 4 herbs, the one with the strongest capability of enhancing soil anti-shearing strength was Schizachyrium delavayi, which was 72.5%, while the lowest was Heteropogon contortus with 2.8%. （2） Roots can reduced soil＇s anti-shearing strength in some special condition, which played a role in loosening the soil.It appeared in the study that the soil anti-shearing strength in the 1st sample of Heteropogon contortus was lower than that in the bare soil sample. （ 3 ） Roots can enhance soil antishearing strength as they enlarge the maximal shear damage displacement. Among the 4 herbs, the largest and smallest damage displacement belonged to Eulaliopsis binate and Cymbopogon distans respectively during the process of destruction ,which increased by 109.4% and 32.7% than that of the bare soil sample.The extension of maximal damage displacement of soil was larger than that of the anti-shearing strength caused by herbs. （4） Among the 4 herbs,Schizachyrium delavayi had the strongest capability in fixing soil, which could be suggested as the pioneer plant for the purpose of ecological recovering, slope protection and plant fencing in ecoengineering in dry-hot valley of Jinsha River.

关 键 词：干热河谷 乡土草本植物 根系固土能力 原位试验 

分 类 号：S157.2[农业科学—土壤学]