基于High-1卫星影像的土地整治遥感监测方法研究与实践

为了找到一种可靠且高效的技术手段来提高国土部门对土地整治成效的有效监管,该文以High-1高分辨率卫星影像为基础数据,以ENVI、Auto CAD和Arc GIS软件为工具,提出了完整的利用高分辨率遥感影像对土地整治成果进行监测的技术方法和操作流程,研究了利用土地整治成果矢量图提取新增耕地、新增道路和新增沟渠信息的方法。最后利用该文方法对南水北调汉江沿线的土地整治工程的某个项目区进行了整治成果的监测和评估,通过实际应用,该方法对新增耕地、新增道路和新增沟渠的监测比分别达到了88.40%,97.34%和98.26%,监测完成后,详细的分析了三者之间监测比产生差异的原因,重点阐述了新增耕地监测比过低的原因,证明了该文方法对土地整治成果监测具有较高的效率,能够应用于土地整治的监管实践。

Method and application of remote sensing monitoring in land consolidation based on High-1 satellite image

Abstract: Nowadays, China spends approximately 100 billion yuan on land consolidation every year, which has positive effects on both newly-cultivated land and efficiency of land use. However, there are still a lot of problems appearing in the process of land consolidation, for instance, the project funds are not used as what is required, the plans of land consolidation are not carried out completely, and there are even Jerry-built projects and false and concealed accounts. Because of these existing problems, the goals of the land consolidation cannot be achieved as expected. To solve the problems, Ministry of Land and Resources of the People's Republic of China developed and used the monitoring and controlling system of land consolidation project as early as in 2009, which monitors and manages the results of land consolidation all over the country. The procedures are as follows: the local authorities that are in charge of the project management will report the results to the higher authorities after land consolidation, and then the competent department will arrange to check the results on the spot. There are some certain problems, for instance, the distribution of land consolidation is wide and the area is large, yet the amount of samples is limited, therefore, the specific results of land consolidation cannot be obtained thoroughly and the system cannot be applied widely. So, it is necessary and urgent for land resources management sectors (LRMS) to find an effective and reliable technical method, with which the LRMS can monitor and evaluate the project results of land consolidation. Based on the panchromatic images and multi-spectral images with high resolution got by the High-1 satellite and the software tools including ENVI, AutoCAD and ArcGIS, the paper puts forward the complete technical method and operation procedures for land consolidation monitoring and evaluation, and also studies the ways of extracting the information of newly increased farmlands, newly-added roads and newly-dug ditches by using vector map, which is made after the land consolidation by project undertaker. Furthermore, from the specific monitoring instance of a land consolidation project along Han River i.e. South-to-North Water Transfer Project, by using the method introduced in this paper, we can find the monitoring ratio of newly increased farmlands is 88.40%, newly-added roads 97.34%, and newly-dug ditches 98.26% in the study area. After monitoring, the paper analyzed the causes of the differences of monitoring ratio between the 3, and especially explains the causes of the lower monitoring ratio of newly increased farmlands in details. They are as follows: first, part of newly-cultivated land is got by means of the landfill of ridges, roads and ditches; second, some project areas haven't made vector maps properly, and the layer names can't match the actual objects in the maps, which causes that the extracted information of new land isn't complete; third, the project undertaker cheats on the area of newly-cultivated land. From all above, we can draw a few conclusions. Firstly, High-1 remote satellite images have both panchromatic images of 2 m resolution and multi-spectral images of 8 m resolution, and after processing the images in the early stage, we have used the algorithm of Gram-Schmidt to fuse the 2 types of images and obtained ideal images in space and spectrum resolution, which can satisfy the requirements of monitoring results in land consolidation. Secondly, we have got the monitoring ratio of newly-cultivated land, new roads and new ditches from one project in the land consolidation along Han River. And the specific example shows that the technical methods in the paper are reasonable and effective. Finally, The ArcGIS software platform is used to process remote sensing images, vector maps of land consolidation results and other reference maps, so that different data from different sources can be unified to GIS. During the process of remote sensing monitoring, we can use various graphics files efficiently, and at the same time it's convenient to modify the maps and print the interpreted maps, which can improve the efficiency greatly.