Study On The GIS-based Ecological Sensitivity Evaluation And Ecological Function Division Urban Ecological Park

Natural ecology has eventually been destroyed with the development of urbanization, and original vegetation has almost died out, which lead to the fact that people seldom have opportunities to enjoy the fun of playing with wild animals. Therefore, it is crucial for us to consider how to lead more wild animals back to the city for recovering and rebuilding wild animal and plant species in order to fulfill people's requirement of living with nature. In my view, building ecological parks will be an important approach. This paper uses GIS technology in the construction of ecological park in Nan Dan county, Guang Xi province to analyze ecological park's sensitivity and makes an ecological function division for the above ecological park based on the ecological sensitivity evaluation. Furthermore, this paper puts forward some proposals for the future construction direction and ecological environment protection. Major conclusions of the research are as follows:(1) This research has obtained the precise DEM data model by using ArcGIS three-dimensional instrument in the high-precision and large scale topographical map which is made in an 1:10000 topographical map with the adoption of RTK. Meanwhile, for the purpose of establishing the ArcGIS platform to get the space and attribute data of dimensional analysis and mapping, the research has screened out ecological sensitive evaluation factors of the city ecological park through the collection of data and investigation of ecological environment. And the ultimate division and map has been completed through the space superposition analysis of each evaluation factor with the adoption of weighted summation tools. This entire technology is based on GIS platform, which guarantees the precision of the evaluation and division and also increases efficiency of the projection, thus providing new approaches for the projection of city ecological park.(2) By selecting and adopting six ecological sensitive evaluation factors of elevation, slope degree, aspect, vegetation cover, water, land cover types, with the support of highly accurate survey data, ecological environment investigation and the GIS technology, this paper aimed at analyzing and comprehensively evaluating the ecological environment sensitivity of the researched territory located in Nandan county, Guangxi province, around which the ecological system has been delegating. After having confirmed the weight of each factor, it displayed that there were 14.73% of extremely sensitive areas,53.90%of highly sensitive areas,24.36% of moderately sensitive areas,2.87%of low sensitive areas and 4.14% of non-sensitive areas. The former three sensitive areas were of 92.99% of the entire region, which demonstrated that the researched region was likely to suffer from ecological environment problems, for example, the vegetation degradation, soil erosion, etc.(3)The research has concluded six sensitivity levels through comprehensive analysis according to which proper methods are adopted in exploitation of the researched territory. Ecological construction has to be put forward to improve vegetation coverage and the diversity of ecological system in extreme sensitive and high sensitive territories so that the distribution areas of these territories and the probability of environmental problems could be eliminated. While in moderate sensitive territory it is important to protect the original vegetation and improve its growing environment purported to prevent its change to high sensitive territory. Exploitation could be implemented in low and non sensitive territories.(4)Based on the evaluation of ecological sensitivity together with the requirement of ecological landscape design and construction, the research has achieved ecological function division, including exploitation and construction territories(landscape construction territoryⅠ, landscape construction territoryⅡ), ecological exploitation control territory, ecological buffer territory and core ecological protection territory. No matter in respect of area or small-class-based number, exploitation and construction territories only count for 5%, while ecological use territory 95%,which indicates that the whole compartment sufficiently considers the requirement of building city ecological park and also reflects the principle of giving propriety to city ecological park. In this way, ecological function division not only directly provides planning basis and guidance for the master plan of city ecological park, but also offers design basis for the construction of ecological scenic.