植被发育斜坡非饱和带土体优先域及其对水分入渗的贡献——以云南省呈贡和昭通玄武岩质斜坡为例  

Preferential Domain Types of Basalt Slope Unsaturated Zone Soil and the Contribution to Water Infiltration:A Case Study of Basalt Slope in Chenggong and Zhaotong of Yunnan Province

作　　者：徐宗恒[1] 徐则民[2] 李凌旭[3] 

机构地区：[1]云南师范大学旅游与地理科学学院,云南昆明650500 [2]昆明理工大学建筑工程学院,云南昆明650500 [3]云南大学滇池学院,云南昆明650228

出　　处：《地理科学》2017年第5期783-791,共9页Scientia Geographica Sinica

基　　金：国家自然科学基金(41502340);国家自然科学基金-云南省联合基金(U1502232);云南省应用基础研究计划项目(2015FD016)资助~~

摘　　要：为了全面得到植被发育斜坡非饱和带土体中优先域结构类型,以2个试验区5个玄武岩斜坡为研究对象,采用染色示踪试验揭示优先域的存在形式及其影响因素,并采用双环入渗试验对不同深度非饱和带土体渗透特征进行测定,揭示优先域对水分入渗的贡献。研究表明:植被发育斜坡非饱和带土体中优先域结构类型除了传统的植物根系腐烂后残留的通道、动物通道、土体干缩裂隙以外,还存在有根系-土体以及砾石-土体接触带空隙以及气候冻融交替产生的裂隙,其中植被根系对大孔隙的影响占主导地位;试验区斜坡非饱和带土体的饱和渗透速度随深度增加有降低的趋势,土体饱和渗透速度最大值高达513.6 mm/h(表层);最小值13.33 mm/h,受广泛分布的优先域影响下形成的斜坡饱和带高渗透盖层对降水入渗的贡献是巨大的。All kinds of soil macropores （preferential domain） is widespread in vadose zone of well vegetated slope, that have an effect on rapid moisture infiltration and supply a useful condition for aquifer feed water. For comprehensive collection the soil macropores types. Taking five basalt slope of two experimental areas as the research object, this article adopts dye tracer experiments to reveal the forms of the preferred domain and its influencing factors. Furthermore, the unsaturated zone soil infiltration characteristics with different depth were determined by the double-ring infiltrometer method in order to explain the contribution of macropores to water infiltration. The results show that preferential domain types also includes the fractures resulted from freezing-thawing events and the contact gap of root system-soil and gravels-soil apart from the traditional dis- covered macropores such as the rotten plant roots channels and faunal tunnels. Of all factors, the plant roots are the first and most important role on macropores. The soil saturated infiltration coefficient, the minimum and maximum of which is 513.6 mm/h （soil surface layer） and 13.33 mm/h, has a reduced tendency with the increase of depth. In conclusion, the contribution of huge permeability vadose zone to water infiltration is enormous.

关 键 词：非饱和带 优先域 染色示踪 双环入渗 高渗透特征 

分 类 号：P642.21[天文地球—工程地质学]