QQ客服 官方微博 反馈留言

题名	高塬沟壑区溯源侵蚀发生发育规律研究—以董志塬为例
学位类别	硕士
答辩日期	2009
授予单位	中国科学院研究生院
授予地点	陕西
导师	王文龙
学位专业	土壤学
中文摘要	黄土高塬沟壑区甘肃董志塬是黄土高原保存最好、面积最大的黄土塬，被誉为“天下黄土第一塬”。该区水蚀与重力侵蚀强烈，塬面溯源侵蚀异常严重，许多沟壑的沟头不断向董志塬腹地推进，塬面不断萎缩，常常吞噬塬面肥沃农田，使塬的面积缩小到不及原来的1/2，并导致沟壑纵横深切，造成了严重的水土流失。塬面不断萎缩的主要原因就是沟头溯源侵蚀。因此，“固沟保塬”对于区域粮食和生态安全具有不可低估的重要作用。本研究以甘肃董志塬沟头溯源侵蚀为研究对象，以土壤侵蚀学等理论为基础，采用野外实地调查与理论分析相结合的方法，查明董志塬沟头溯源侵蚀的分布特征、规模及危害，阐明影响发生溯源侵蚀的主要因素，探讨董志塬溯源侵蚀发生类型、发生阶段，分析典型地段沟头溯源侵蚀的特点，并提出治理沟头前进的途径和措施，为黄土高塬沟壑区“固沟保塬”提供科学依据，对区域生态环境建设具有重要的科学意义和实用价值。主要研究结论如下：1. 影响董志塬溯源侵蚀的因素包括自然因素和人为因素。自然因素主要有降雨、土壤、地形、植被等。人为因素主要包括工程建设、城市发展、不合理的工厂选址和没有沟道防护措施的城市排洪排污。2.董志塬沟头溯源侵蚀按照其形成机理分为水力冲刷型、陷穴诱发型、裂缝诱发型和人为诱发型。通过考察发现，董志塬沟头溯源侵蚀主要是水力和重力作用共同影响的结果。从其形成机制来看，一为沟头上方汇集的径流直接冲刷造成了沟头的迅速延伸类型；另一为径流在沟边附近的裂缝、陷穴处下渗，从而导致沟头的坍塌、滑落与沟头前进类型。从溯源侵蚀的发生强度来看，是异常剧烈的，已经对塬面的土地、村庄、道路、民居和工厂造成了严重的威胁。对于黄土高塬沟壑区的沟头防护的治理，应该放在更为重要的地位考虑。3. 总结了董志塬溯源侵蚀发生过程。溯源侵蚀发生类型虽然形式不同，但是侵蚀过程从时间顺序上来讲可划分为水力冲刷、水力重力共同作用、重力侵蚀三个阶段。4.总结提出了董志塬溯源侵蚀防治措施。董志塬溯源侵蚀的防治措施概括为塬面措施和沟底措施两大类。塬面措施是在沟头上方来水方向修筑涝池或涝池群拦蓄地表径流。此外还有蓄水堰、沟边防护埂、防护墙等措施来蓄存或分散径流，达到巩固沟岸的目的。其次是沟底修筑沟底谷坊，抬高侵蚀基准面，防止沟床下切。在条件允许、经济可能的情况下，要选取合适的沟底地段安排淤地坝和引洪漫地，使泥沙就地拦蓄，削减洪峰，调节径流。
英文摘要	Dongzhiyuan is the best preserved and largest Plateau, which is known as the "the first Plateau in the world " in this area .The head-cut erosion companying with serious water erosion and gravity erosion pushs forward the hinterland to continuous shrinkage of Plateau surface to less than 1/2 of the former land. Therefore, the "protecting the plateau from erosion" plays an important role in the regional food and ecological security. In this paper,we studied the head-cut erosion of Dongzhiyaun on Loess Plateau.By field investigation and theoretical analysis, we surveyed the head-cut erosion developing and distribution characteristics, and clarified the distribution of gully head advance and the development law, put forward specific measures to combat head-cut erosion.The main conclusion of the study are as follows:1. National factors and human factors are the main factors impacting head-cut erosion. National Factors,including rainfall, soil, topography, vegetation and so on. Human factors accelerate soil erosion,such as the construction projects, urban development, the predatory mode of operation and unreasonable land use.2. According to the mechanism of its formation,we can divide it into four types:water erosion type,sinkhole-induced type,crack-induced type and man-induced type. We found that it is the combined effect of water and gravity resulting in head-cut erosion. From the formation mechanism,the first type is that the runoff from up stream of gully speeds up the development of head-cut erosion directly;the other is that runoff infiltrates in the vicinity of the cracks, sinkhole, resulting in the collapse of the first groove , slide with the gully head extension forward. Head-cut erosion is the most important erosion type ,playing an important role in the loess plateau and gully region,which has been posing a serious threat to the avaiable land, farms, villages, roads, houses and factories. So taking treatment to control the head-cut erosion should be placed on the more important status.3. We summed up the process of head-cut erosion occurrence. Although the difference of formation type,but they all include three stages of runoff-wash erosion, the combined effect of gravity and water, gravity erosion.4. We put forward the control measures.It can be summarized as plateau surface measures and gully bottom measures.Plateau surface measures:comprehensive treatment can be generalized by "block,store,drain and lead” four words. Practice has proved that to build flood pool or pool group on the overhead of the gully is the most practical way to retain surface runoff. gully bottom measures:when all the measures mentioned above can not cut off the runoff,we take the gully bottom measures as the secend defense. The main approach is to build a solid embankment，elevating the erosion datum plane,protecting the gully bottom from cutting.
公开日期	2011-07-01
内容类型	学位论文
源URL	[http://ir.iswc.ac.cn/handle/361005/4120]
专题	水土保持研究所_水保所知识产出(1956-2013)
推荐引用方式 GB/T 7714	. 高塬沟壑区溯源侵蚀发生发育规律研究—以董志塬为例[D]. 陕西. 中国科学院研究生院. 2009.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。