灌丛化对高寒草甸土壤水力性质的影响  

Effects of Shrub Encroachment on Soil Hydraulic Properties in Alpine Meadow

作　　者：尹霞 李冬梅 李易 王平[1] 刘淑英[1] 高永恒[2,3] YIN Xia;LI Dongmei;LI Yi;WANG Ping;LIU Shuying;GAO Yongheng(College of Resources and Environment,Gansu Agricultural University,Lanzhou 730070;Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041;Institute of Biology,Chinese Academy of Sciences,Chengdu 610041)

机构地区：[1]甘肃农业大学资源与环境学院,兰州730070 [2]中国科学院水利部成都山地灾害与环境研究所,成都610041 [3]中国科学院成都生物研究所,成都610041

出　　处：《水土保持学报》2022年第5期121-129,共9页Journal of Soil and Water Conservation

基　　金：四川省重点研发计划项目(2022YFS0489);国家重点研发计划项目(2016YFC0501802)。

摘　　要：全球气候变化背景下,青藏高原高寒草甸灌丛化已经成为青藏高原植被景观的主要变化趋势。为了更好地认识和理解灌丛化与高寒草甸生态系统的关系,以青藏高原东缘川西锦鸡儿(Caragana Erinacea Kom)和金露梅(Potentilla Fruticosa)灌丛化高寒草甸为对象,采用环刀浸泡法和双环入渗法研究了其在未灌丛化、轻度灌丛化、中度灌丛化和重度灌丛化阶段土壤持水和入渗能力特征。结果表明:(1)2种灌丛化草甸土壤容重在中度灌丛化阶段最低,总孔隙度在中度灌丛化阶段最高。(2)随着灌丛化程度的增加,2种灌丛化草甸土壤含水量呈增加趋势,表现为在重度灌丛化阶段最高;土壤毛管持水量、田间持水量和最大持水量呈抛物线变化趋势,在中度灌丛化阶段最大。(3)2种灌丛化草甸土壤的初渗率、稳渗率和入渗速度随灌丛化程度的增加总体表现为增加趋势,其中在中度和重度灌丛化阶段显著高于未灌丛化阶段。(4)相关性分析表明,灌丛化草甸土壤的入渗指标与土壤含水量、非毛管孔隙度有显著相关关系。因此,高寒草甸灌丛化过程中,土壤水力性质的改变通常发生在中度和重度灌丛化阶段。Under the background of global climate change,shrub development of alpine meadow has become the main trend of landscape change in Qinghai-Tibet Plateau.In order to better understand the relationship between shrub and alpine meadow ecosystem,this paper taking shrub alpine meadow of Caragana Erinacea Kom and Potentilla Fruticosa in the eastern margin of the Qinghai-Tibet Plateau as an example,characteristics of soil water holding capacity and infiltration capacity during non-shrub,mild shrub,moderate shrub and severe shrub were studied by using ring knife soaking method and double ring infiltration method.The results showed that:(1)Soil bulk density was the lowest and total porosity was the highest in moderate shrub stage.(2)With the increase of degree of shrub,soil water content of two kinds of shrub meadows showed an increasing trend,and it was the highest in heavy shrub stage.Soil capillary water capacity,field water capacity and maximum water capacity showed a parabolic trend,and maximum water capacity was the highest in moderate shrub stage.(3)The initial infiltration rate,stable infiltration rate and infiltration rate of two kinds of shrub meadow showed an increasing trend with increase of degree of shrub,and infiltration rates in moderate and severe shrub stages was significantly higher than that in non-shrub stage.(4)Correlation analysis showed that soil infiltration index was significantly correlated with soil water content and non-capillary porosity.Therefore,changes of soil hydraulic properties usually occur in moderate and severe shrub stages during alpine meadow shrub development.

关 键 词：高寒草甸 灌丛化 土壤持水 土壤入渗 

分 类 号：S152.7[农业科学—土壤学]