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

发布时间：2018-04-08 09:24

本文选题：非饱和带　切入点：优先域　出处：《地理科学》2017年05期

【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。
[Abstract]:In order to obtain the structure type of preferential zone in unsaturated soil of the slope, five basalt slopes in two experimental areas were taken as the research objects. The existence of priority region and its influencing factors were revealed by staining tracer test.The characteristics of soil permeability in unsaturated zone with different depth were measured by double ring infiltration test to reveal the contribution of preferential region to water infiltration.The results show that the preferential structural types of soil in slope unsaturated zone are not only the traditional residual channels of plant roots, but also the animal channels and dry shrinkage fissures of soil.There are also gaps in the contact zone of root soil and gravel soil, and cracks produced by climate freeze-thaw alternately, in which the influence of vegetation roots on macropores is dominant.The saturated permeability velocity of unsaturated soil in the slope of the test area tends to decrease with the increase of depth.The maximum saturated permeability velocity of soil is as high as 513.6 mm / h (surface layer; minimum 13.33 mm / h). The high permeability caprock formed under the influence of widely distributed preferential region is a great contribution to precipitation infiltration.
【作者单位】：云南师范大学旅游与地理科学学院;昆明理工大学建筑工程学院;云南大学滇池学院;
【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~~
【分类号】：P642.2;Q948

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