| Urban green space as an environmental factor plays an important role in advancing the sustainable development of urban. Based on the quantitative description and analysis of the effect scale of landscape composition, structure, and spatial pattern, and the analysis of landscape connectivity in Changsha city, principles and methods in landscape ecology are introduced to reveals the spatial structure of the green space landscape as well as the regular pattern and scale effect of spatial changes with the technological support of GIS and RS. It provides a theoretical reference for landscape planning of urban green space system. Meanwhile, it has an important significance to develop the ecological function of urban green space of Changsha.The paper analyses the landscape pattern of urban green space system of changsha city. Which is classed to five kinds included parks, production green space, protection green space, subsidiary and other green space according to the classification of green space function. The research findings are as follow:(1)The distribution of green space landscape'type is uneven. Other green space is in the majority in the total of green space area, which area is 5725.85 hm2, and takes up 57.6 percentages; while the subsidiary green space occupy utterly predominance by the proportion of each type patch accounts for the total number of patch, which is 8594 and takes up 92.9 percentages, but which area just is 2545.85 hm2, and accounts for 25.61 percentages; the area of parks is 1015.44 hm2, which takes up 10.22 percentages; the area of production green space is 575.86 hm2, which takes up 5.79 percentages; the area of protection green space is the lightest of 77.86 hm2, and only takes up 0.78 percentages.(2)Different landscapes pattern indexes have different sensitivity response to varied grain size. With gradually increasing analysis scale, the degree of landscape fragmentation shows the decreasing trend by patch density, mean patch size and fragmentation index. However, separation index shows the rising trend and is the contrary of fragmentation index. While aggregation index shows the decreasing trend, which shows that the landscape aggregation doesn't acts contrary to fragmentation degree.(3)The results shows that Shannon's diversity index, Shannon's evenness index and dominance index are not sensitive to varied grain size, just which have a slight change at the grain size of 120m.In different scales, the average of the indices of diversity just is 1.04, the average of the indices of evenness is 0.4907, and the average of the indices of dominance is 1.2726.(4)The results shows that the relative importance (dâ…¡C and dPC) of patches in landscape is not sensitive to varied grain size. PC and IIC were not strongly scale-dependent. With the enhancement of motor ability of the animals, the scale sensitivity has been a decrease.In six kinds of MMU, the integral indices of connectivity (IIC) is low, the averages of which are 0.2771,0.3090,0.2725,0.2807,0.2674 and 0.3214. The probability indices of connectivity (PC) are relative higher, the averages of which are 0.5012,0.4778,0.4605,0.4590,0.4681 and 0.5098in six kinds of MMU. The connectivity of green space landscape in Changsha City is not so well on the whole.(5)The article uses spatial analysis tools and network analysis in ARCGIS and a analysis is conducted to analyze the accessibility of urban green spaces, public parks and serving area of public parks. Which are necessary supplements to the indictor system presently used to evaluate eco-city.The results show that the proportion of the area of accessibility which occupies the whole area of city is 66.01 percentages within 30 min. The area of accessibility of public parks is 1985.55 hm2, takes up 3.85 percentages of the whole area of city within 15min by walk. Serving area of public parks within 1000m of radius just is 9269.65hm2, takes up17.97 percentages. At the same time, distribution of green space of varied administrative region is unreasonable.
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