竖井是一种特殊的潜蚀地貌类型,是大规模土壤侵蚀背景下不容忽视的灾害性环境问题。竖井的发育是冲沟侧蚀后退的一种方式,对冲沟沿线形态影响巨大,研究其成因和演化过程对认识冲沟的侧蚀和后退机制具有很大的参考价值。基于对元谋干热河谷沙地村竖井群的实地考察和测量,将竖井的发育划分为萌芽期、扩张期、完整期、破碎期和残夷期5个阶段,不同发育阶段其平面形态与剖面形态具有显著的差异;完整期竖井的形态最具代表性,其长度、宽度和深度的变化范围分别在0.75-3.29 m、1.01-2.84 m、1.98-10.26 m,长宽比在0.3-3.1;竖井的形态与发育过程主要受到降水和地表径流、构造、土体性质、地形与植被等因素的控制。这一研究有助于认识竖井的形成与演化,也为实践中工程地质灾害防治与沟蚀监测提供科学指导。
The vertical hole is a special kind of piping landforms; it is the disastrous environmental problem that cannot be ignored under the background of large-scale soil erosion. The development of vertical hole indicates the lateral erosion of gully,so that it has a huge impact on shoulder line shape of gully. It is very important to study the evolution and formation of vertical holes for understanding the mechanics of lateral and backward erosion of gully.Based on the investigations of vertical holes at Shadi Village of Yuanmou Dry-hot Valley,they can be divided into germination period,expanding period,complete period,broken period and residual period. There are significant differences between plane shape and cross-sectional shape of vertical hole at different developmental stage. The vertical hole of complete period is the most representative stage,the changes of long axis,short axis and the depth of vertical holes are in the range between 0. 75 - 3. 29 m,1. 01 - 2. 84 m,1. 98 - 10. 26 m; the ratio of long axis and short axis is between 0. 3 - 3. 1. The morphology and developmental process are mainly controlled by the factors of precipitation and surface runoff,structure,soil properties,terrain and vegetation etc. This paper not only contributes to the understanding of the formation and evolution of the vertical hole,but also provides scientific guidance for treatment of engineering geological hazard prevention and monitoring of gully erosion.