Study On Green Space Landscape Along Gradients In The Urban Fringe Of Guangzhou City Based On GIS

With the influence on environment change by man's exploitation, the contradiction between urban land expansion and land use, economic development and resources protection is intensified. During all the studies of all kinds of regional land use, the urban fringe is the most fragile area of environment and also the joint area of human factors. The urban Green space system plays an important role in improving the quality of ecological environment of urban fringe area, adjusting the ecosystem to be balanced and keeping physically and mentally healthy of residents.Combined with traditional statistic methods, this article takes the strut by the Remote Sensing method and the formidable space analysis function of Geographical Information System to gain massive spatial data. Attribute data is also supplemented from statistic references. Choosing Panyu district as a studied object, this thesis divides it into three environmental gradients areas according to its natural characteristics and the humanities characteristics to research the green space structure of fringe area in Guangzhou city and the relation to impact of urbanization on gradient change. Through overall analysis and discussion, the following conclusions were drawn.1. The results of the spatial structure of different gradients' land use types show that: Because the humanity disturbance tends to weaken gradually along the gradient zones, landscape diversity index and evenness index decrease. The artificial landscape types gradually reduce. The nature or half-natural landscape types increase piece by piece. The geometry shape of patch is simplier than others within closing to gradients of the city.2. According to the research goal, Green space landscape is divided into four types: public green space, residence green space, subsidiary green space and agriculture-forest vegetation. The analysis of the green space structure in different gradients indicates that: the spatial distribution of different green space types is asymmetrical in total area. The diversity and evenness of green space landscape reduced and the fragmentation index of patch exhibits descendent tendency along the gradients, showing a significant relationship between the quality of green space's distribution and the extent of disturbance. The lower fragmentation index goes;the quality of green space increased. The landscape mean fractal dimension index is generally smaller, which is disadvantageous to maintenance and establishment of city biodiversity.3. The relativity between thermal field's distribution and the effect of green space is also studied. The distribution of heat islands has many centers. It is also found that the distribution of city energy-consuming and landcover affects directly the upper ground temperature. In opposition of heat islands, there are a plenty of micro-climate islands, which is covered by waters or vegetation. The analysis of typical area proves that scientific and rational distribution of green space can reduce or even eliminate the thermal field's effect.4. The entropy model for green space landscape based on the thermodynamics principle and the spatial analysis theory of Geographical Information System is effective and available to assess the spatial structure stability and ecological service function. The data needed in the model are easy to calculate, which mean that the green space landscape entropy model could be in practice.