摘要
地貌重塑是废弃矿区土地复垦与生态重建的重要基础部分和重点研究的技术问题之一。该文根据流域地貌学及其自相似原理,利用ArcGIS技术重新规划了废弃矿区的子流域及沟道、计算了矿区邻近未干扰子流域地貌形态特征数据并作为参照的标准;在此基础上结合Geofluv模型重建了北京市房山区黄院废弃采石场的小流域地貌,探讨了基于小流域自然形态的废弃矿区地貌重塑原理与技术方法,分析了重塑后的与未干扰的子流域形态特征间关系。结果表明,重塑后子流域地貌形态是相对稳定的、自然的,并与未干扰的子流域形态特征比较相似;用地貌系统信息熵值判断出重塑后地貌起伏变化小,受侵蚀强度弱,水土流失趋向于非常缓和。该文研究成果为废弃矿区地貌重塑的研究提供了一种新思路。
Topographic reconstruction is a crucial part of land reclamation and ecological rehabilitation because the resulting geography landscapes are the foundations for all subsequent reclamation practices and the surfaces for future land uses. It is also ranked among the most important research technical problems. Nature can provide analogues for mined or mining landscapes during disturbed-land reclamation according to landscape stability and according to the reconstructed structure blending in with the surrounding undisturbed landscape. In terms of the watershed geomorphology and the principle of self-similarity theory, the sub-catchments and channels of abandoned mines were re-planned by using ArcGIS soft technology and a practical survey in this paper. At the same time, the topography characteristics of adjacent, undisturbed catchments were calculated by applying an ArcGIS Hydrologic analysis tool, which was taken as the following simulation reference standard. Then the topography in a sub-watershed unit in the Huangyuan abandoned quarry project of Fangshan county in Beijing city was reconstructed by using a Geofluv （Natural Regrade） module driven by geomorphic principles, in which this module simulated the function of the natural landscape that would evolve over time under the physical and climatic conditions present at the site to water and sediment from the land surface in a stable hydrologic equilibrium. Moreover, the theory and technical method of the reconstructed topography were studied. The initial study of the sub-watershed on the undisturbed landform in the project’s vicinity were selected and calculated to develop a stable channel design and reconstruction guidelines by using GIS spatial analysis tools, and the selected geomorphologic characteristics index were first and second order sub-watershed, the average sub-watershed area, main channel, drainage density, watershed roundness, average elevation difference, and average slope, which provided targets for topographic reconstruction. In this case, the average second order drainage density that represented the stable sub-watershed size for the local condition was 13.84km/km2. Moreover, the average second order drainage density of the reconstructed topography which simulated the natural landform evolution to the stage in balance with the local environmental condition was 14.52km/km2 on the basis of a re-planning of reconstruction sub-watershed and main channel, which achieved the desired design goals. The results showed that the reconstructed Huangyuan topography in which the hydrologic and fluvial geomorphic analyses and stable channel parameters were determined, and based on site-specific data, were relatively economical, stable, and natural, which was similar to the undisturbed catchments’ geomorphology. Finally, the relationship of geomorphologic characteristics between the reconstructed sub-watershed and the undisturbed ones was analyzed and the ratio of the index was almost similar. A topographic reconstruction simulated a relatively stable sub-watershed performed by geomorphic processes with the creation of a basin composed of slope and channels in orderly spatial arrangements and functioning for the transportation of water and sediment. The geomorphic information entropy analysis showed that the geomorphology changed very slowly after topographic reconstruction and the erosions on watershed were also gradually reduced. This study provided a novel viewpoint for the topographic reconstruction of an abandoned mine.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2014年第1期236-244,共9页
Transactions of the Chinese Society of Agricultural Engineering
基金
林业公益性行业科研专项(200904030)
北京市财政资金资助项目(PXM2013-178203-000005)
关键词
土地复垦
地貌形态
矿区
流域
重塑
地貌系统信息熵
land reclamation
geomorphology
mines
watershed
reconstruction
geomorphic information entropy
