骊山—横岭—白鹿塬地区溯源侵蚀空间分异性研究

发布时间：2018-01-10 00:28

本文关键词：骊山—横岭—白鹿塬地区溯源侵蚀空间分异性研究　出处：《西北大学》2015年硕士论文　论文类型：学位论文

【摘要】：溯源侵蚀是沟谷地貌发育的主要侵蚀方式之一,也是我国当前发生最为频繁的沟谷发育方式,与土壤侵蚀产沙与地貌发育关系密切。骊山-横岭-白鹿塬地区地貌类型多样,有黄土台塬、黄土丘陵、河流川地和土石低山丘陵等。该区域沟头的溯源侵蚀作用强烈,且不同地貌类型的溯源侵蚀特征也不尽相同。因此,深入研究该地区沟头溯源侵蚀量化特征和地域性特征,不仅有助于揭示该地区沟头发育演化特点,而且对于区域水土保持治理、土地资源保护利用均具有重要的价值。本文在总结前人的研究成果和经验的基础上,依据地貌学、水文学和空间统计学等相关学科知识,综合运用GIS技术主导下的数字地形分析、地统计分析方法,遥感影像分析解译等室内实验方法,结合沟头实地调查等野外工作方法,以ArcGIS软件为主要技术平台,研究分析了骊山-横岭-白鹿塬地区的沟头溯源侵蚀地域差异性和空间分异特征。本文首先详细介绍了沟头的相关理论,结合沟头的地貌学特征,对其范围下了定义,并发展了基于5米分辨率DEM数据的侵蚀沟头提取方法,随后对研究区进行侵蚀沟头提取实验,得到了较好的效果。接着选取了表征沟头溯源侵蚀强度、残余量和潜能的4个量化指标,其中,沟头频度指标表征溯源侵蚀强度,逼近度指标表征溯源侵蚀残余量,相对高程和沟头的平均坡度指标表征溯源侵蚀的潜能。通过对上述4个指标进行实验样区的提取并分析发现,选取的量化指标能够很好的反映研究区内不同地貌类型的沟头溯源侵蚀特征。最后,通过对骊山-横岭-白鹿塬地区均匀分布的28个实验样区的沟头溯源侵蚀量化指标进行空间分异规律分析,发现研究区内处于不同地貌发育阶段的沟头溯源侵蚀具有一定的分布规律：沟头频度指标在研究区内由南至北呈现递增的趋势；逼近度指标则呈现递减的趋势；该两项指标的变化趋势与研究区内不同地貌特征和沟头溯源侵蚀特征相符合,反映了两项指标与地貌发育程度的关系密切。相对高程和沟头的平均坡度指标则呈现出骊山地区和白鹿塬地区稍高,中间横岭地区稍低的分布规律,也与研究区内不同地貌特征和沟头溯源侵蚀特征密切相关。本次研究是对沟头提取和沟头溯源侵蚀量化研究的一次大胆的尝试,虽然存在一些不足之处,但是对于进一步揭示沟谷地貌发育与沟头溯源侵蚀的定量关系具有一定的参考价值。
[Abstract]:Traceability erosion is one of the main erosion ways of valley geomorphology development, and it is also the most frequent gully development mode in China at present. It is closely related to soil erosion, sediment yield and geomorphology development. There are various landforms in Lishan, Hengling and Bailuyuan areas, including loess plateau and loess hilly area. The traceability erosion at the head of the region is very strong, and the characteristics of traceability erosion of different geomorphological types are different. Further study on the quantitative and regional characteristics of trench head traceability erosion is not only helpful to reveal the development and evolution characteristics of gully head in this area, but also to regional soil and water conservation. Conservation and utilization of land resources are of great value. This paper summarizes the previous research results and experience, according to geomorphology, hydrology and spatial statistics and other related disciplines. Comprehensive use of GIS technology led by the digital terrain analysis, geostatistical analysis methods, remote sensing image analysis and interpretation of indoor experiments, combined with field work methods such as trench field investigation. Using ArcGIS software as the main technology platform, this paper studies and analyzes the regional differences and spatial differentiation characteristics of trench head traceability erosion in Lishan-Hengling-Bailuyuan area. Firstly, this paper introduces the relevant theory of Goutou in detail. Combined with the geomorphological characteristics of the gully head, the scope of the definition, and the development of a 5m resolution DEM data based erosion head extraction method, and then the study area of erosion gully head extraction experiment. Then four quantitative indexes were selected to characterize the trace erosion intensity, residual amount and potential. Among them, the trench head frequency index was used to characterize the traceability erosion intensity. The index of approximate degree represents the residual amount of traceability erosion, and the average slope index of relative height and trench head represents the potential of traceability erosion. The selected quantitative indicators can well reflect the erosion characteristics of different geomorphological types in the study area. Finally. This paper analyzes the spatial differentiation law of the quantitative index of the racehead traceability erosion in 28 experimental areas uniformly distributed in the Lishan, Hengling and Bailuyuan regions. It is found that the trench head traceback erosion in different geomorphological development stages in the study area has a certain distribution law: the frequency index of trench head is increasing from south to north in the study area; On the other hand, the degree of approximation tends to decrease; The change trend of these two indexes is consistent with the different geomorphological features and trench head traceability erosion characteristics in the study area. The two indexes are closely related to the degree of geomorphologic development. The relative elevation and the average slope index of the gully head show the distribution law of the Lishan region and the Bailuyuan area slightly higher, and the middle Hengling area slightly lower. It is also closely related to different geomorphological features and trench head traceability erosion characteristics in the study area. This study is a bold attempt to extract and quantify trench head traceability erosion although there are some shortcomings. But it has certain reference value for further revealing the quantitative relationship between valley geomorphology development and trench head traceability erosion.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P931;P208

【参考文献】