不同植被群落斜坡非饱和带土体大孔隙流试验研究  

Research on Macropores Flow in Unsaturated Zone Soil of Slopes under Different Vegetation Community

作　　者：曾强[1,2] 徐则民[1] 张有为[1] 张惠宁[3] 梅雪峰[1] 任喆[1] 

机构地区：[1]昆明理工大学建筑工程学院,云南昆明650500 [2]湖南工学院,湖南衡阳421002 [3]武汉大学土木建筑工程学院,湖北武汉430072

出　　处：《西南交通大学学报》2017年第4期694-704,共11页Journal of Southwest Jiaotong University

基　　金：国家自然科学基金-云南联合基金重点资助项目(U1033601;U1502232)

摘　　要：为评价自然降雨条件下天然斜坡非饱和带土体大孔隙流分布模式,保留坡面原始状态,模拟降雨过程,开展了亚甲基蓝染色示踪试验;结合水分穿透法,采集高精度染色剖面图像,基于图像处理、差方分析、回归分析等方法研究了降雨过程中高盖度(>90%)斜坡土体大孔隙流的分布及其影响因素.结果表明:对比草本植被群落土体,木本植被群落土体剖面大孔隙流分布范围(染色覆盖率46.18%~63.55%)更大,连续性程度更低,分化程度(染色路径数203~8 599)更高,染色模式更复杂;大孔隙二维流态一定程度上能反映其三维流态;坡向效应在与土体大孔隙拦截效应竞争降雨分配过程中,更倾向于顺坡向(最大染色覆盖率63.55%、59.67%)土体的降水垂直入渗;根系尺寸并非控制土体大孔隙尺度的唯一因素(平均孔径分别为1.23~2.03 mm、1.34~2.23 mm);团聚体颗粒本身也可存在根系通道.To evaluate Macropores Flow in unsaturated zone Soil of natural Slopes under rainfall conditions, A dyeing tracing test with methylene blue was carried out based on retaining the original state of the slopes and simulating rainfall process. Combined with water breakthrough method and high- precision dyeing profile image, based on image processing, differential and regression analysis, distribution and influence factors of macropore flow in high coverage（ 〉90% ） slope during the rainfall process were studied. The results show that ： comparing with herbaceous vegetation community soil, the distribution range （ dyeing coverage is at 46. 18% - 63. 55% ） of macropores flow in the profile of woody vegetation community soil is larger, the continuous degree is lower, the differentiation degree （dyeing route number is at 203 - 8 599 ） is higher, the staining patterns are more complex. Macropores flow patterns of 2D can reflect that of 3D. In the rainfall distribution process, competing with the interception effect of macropore in soils, slope orientation effect is tend to infiltrate vertically along the slopes （max dyeing coverage are at 63.55% and 59. 67% ） . Roots size is not the only factor to control macropores scale （the mean pore sizes are at 1. 23 - 2. 03 mm and 1. 34 - 2. 23 m m ） . Aggregate particles themselves can also have root channels.

关 键 词：植被发育斜坡 降雨入渗 滑坡 大孔隙 

分 类 号：TD12[矿业工程—矿山地质测量] P32[天文地球—地球物理学]