The Calculation Of The Two-Dimensional Vegetation Quantity In Central Area In Wuhan Based On GIS

The regulation of Ministry of Construction in China about greenbelt index includes four items: per capita green area, per capita public green area, ratio of green space, urban green coverage. Using four quota indexes to evaluate the level of urban green has either scientific ration or reflect real situation. Consequently, the calculate method for greenbelt ecological compensation has been put forward. At the same time, GIS has penetrated into urban landscape areas gradually. GIS of greenbelt can obtain the actuality of urban green recourse and change information accurately.This research mainly includes two parts: greenbelt information drawing and subsistent ecological compensation ability analysis. Conception related greenbelt, the study progress of greenbelt evaluation index, GIS and interrelated technology using in urban greenbelt study have been introduced. Applying ERDAS IAMGINE software following this progress: image selection, image disposal, computer supervise classification, alternant correction, greenbelt information abstracting, statistic accounting, in accordance with leafy arbor, conifer, bush, grass, farmland, hedge, greenbelt information has been extract respectively.According to investigate result, the three-dimensional distribution pattern of greenbelt ecological compensation ability of Wuhan can be draw. From this pattern, we can infer that the greenbelt distribute unequally, separately and the difference of area is prominent. Applying the conception of green equivalent, we replace all greenbelt of research zone by corresponding grass area.We discuss above grass area distribution pattern in items of executive region, analysis subsistent greenbelt ecological compensation ability of different territory. The consequence shows, the general level of greenbelt can satisfied demand for c-o equipoise in Wuchang district and Hongshan district, the Green equivalent of other districts need the improve according to various levels.Combine the grass distribution pattern with population actuality, and figure up all grass area needed by central areas, and compare with the grass area actuality. Consequently, the relationship between population and greening actuality can be obtained. As for the population distribution of each street, the account of greenbelt demanding should be précised. The consequence shows that the general Green equivalent of research district can supply fine air. However, for each street, the demanding greening level is dissimilar.Overlay the grass distribution pattern with urban land use types distribution diagram, and then analyze the greenbelt ecological compensation ability of various types of urban land. The result shows that the difference of green equivalent of inhabit area is remarkable. At the same time, the green level of education and scientific research and industry is insufficient in general.Ultimately, the problems of existing greenbelt of center in Wuhan have been elaborated simply and the questions arisen during research have been discussed.