Characterization of preferential flow pathways by using the dye tracer test in Jiu Feng National Forestry Park
Dye tracer tests were conducted on two small undisturbed Platvcladus orientalis (Linn.)Franco plots of about 1m2 located in the downhill of the Jiu Feng National Forestry Park in order to figure out the relationship among preferential flow, soil genetic horizons and the soil water repellency. Brilliant Blue solution was applied by ponding a 50-mm pulse onto this two plots respectively and both horizontal and vertical soil profiles were gotten every 2-5cm afier 24 hours. Results showed that the dye pattern of eluvial horizon was uniform while illuvial horizon and below show nonuniform. Dye tracer penetrated vertically via preferential pathways to 71cm (vertical soil profiles) depth, while most of the soil matrix remains unstained. The water repellency experiments showed weak water repellency in soil surface which may affect the preferential flow pathways. We conclude that preferential flow distinctly shows heterogeneity among the soil horizons. The eluvial horizon is dominated by matrix flow; however, the illuvial horizon is dominated by preferential flow inversely. The decayed root channel and the fecal pellet of earthworm in the stained region plays an important role in the generation of preferential flow pathways. In addition, some discrete dye pattems in the vertical profiles show that the horizontal flow is prevalence in this region.
preferential flow soil genetic horizon soil water repellency dye tracer
Wenwei Shao Jianzhi Niu Zixing Xiao Weili Zhu Yousong Zhang Qinglong Wang
Key Laboratory of Soil and Water Conservation & Desertification Combating, Beijing Forestry Universi Huangling forestry farm, yitong county, Jilin Province 130713, China
国际会议
西安
英文
794-801
2010-10-11（万方平台首次上网日期，不代表论文的发表时间）