| As a very important part of the urban ecological system, urban green ground system has ecological, economic and social function and possesses a remarkable place in the urban compound system. How to maintain and keep good urban green space landscape pattern, maximizing its ecological services is an important way of achieving sustainable urban development. At present, there have been many study of urban green space landscape pattern and function of ecosystem services but consider the landscape pattern changes as assessment factor to consider the value of ecosystem services is still relatively rare. And basically qualitative research-based, quantitative analysis of the study is small.The thesis regards Changsha urban area as research range, with the green land current situation picture of Changsha as the basic picture, combining other map data,fields and investigate to divide into view types. Calculating and analyzing the above-mentioned maps, obtaining the corresponding attribute data with AutoCAD2009and GIS software, such as the type of the spot piece, quantity, shape and area, and then analyze the pattern of the urban area green land view of Changsha according to these data, obtain corresponding spatial information, and compare piece of all kinds of spots carrying on systematicness, using view ecology to combine the relevant knowledge of the urban planning, propose the optimization countermeasure of the land range inner green land spot piece space pattern of Changsha. Meanwhile, classify to ecosystem service function according to domestic and foreign experts and scholars, combine the urban green land situations and people's development and utilization current situations to the urban green land of Changsha, Divide the urban green land ecosystem service function in Changsha into two big kinds having use value and without use value, on a basis of estimation of the ecological service value coefficient in the forest land, consult" the ecological service value of the Chinese land ecosystem unit area acts as the scale ", estimate economy to all kinds of ecological service functions. The result of study shows:Landscape pattern(1) Changsha is improving its urban green space system during the Course of Urbanization. The greening construction develops rapidly and rate of greenery patches have greatly increased. From1998to2009,the green area in Changsha have increased from8134hm to2976hm2,the Ratio of Green Space have increased from25.9%to33.55%。In the composition of various types of green space system,institution affiliated Greenland occupy the most proportion, secondly is park irrigation and landscape forestry greening.In2011, park irrigation will account for a dominant position and then will be institution affiliated Greenland and residential area Greenland.(2) Based on the analysis of landscape pattern, the average size of giant plaque composition of74.19%, large plaque composition7.67%, large and middle plaque composition of8.25%, medium sized plaque composition of8.06%,miniature plaque composition of1.83%.According to the above analysis of the data we can obtained percentage of the plaques which giant patches9.45%, large plaque5.12%,large and middle plaque10.63%, medium sized plaque32.28%,miniature plaque42.52%respectively.(3) Fractal dimension is used to measure the complexity of patch shape indicators, it shows that the data more close to1.0,the more monotonous green shapes are and making it difficult to form a marginal effect. According to the data, the magnitude of fractal dimension in Changsha have a lower overall level and not obviously patch boundary,This is very unfavorable for Creating a diversity of landscape space and enhancing biodiversity in green space system.(4) From the scale effect of landscape connectivity index, the index of the whole connectivity IIC is very low. In the6kinds of MMC,the average of IIC is:0.2771,0.3090,0.2725,0.2807,0.2674,0.3214separately; PC as the index of possible connectivity is relatively higher, in the6kinds of MMU, the average is:0.5012,0.4778,0.4605,0.4590,0.4681,0.5098separately, but it's only in the middle level. With the continuously increase of the searching range, the IIC and PC increases gradually in the6kinds of MMU, the change of PC is especially obvious, this explain that in the searching range of the larger ecological process, the same landscape connectivity is higher; but with the continuously increase of MMU, the IIC and PC change a little in the same searching range, it's not sensitive for the scale variation.(5) Evaluating various types of green space in Changsha based on the fuzzy mathematics theory, making an overall assessment of the landscape green. We can draw the following conclusions:evaluation of excellence is park green space.Other green space has certain advantages in landscape pattern index such as quantity, area and landscape isolation. The better evaluation is other green space, although from the area proportion and fragmentation index, the productive plantation area occupies the dominant position. But according to the overall rate of green, productive plantation area's dominance is not high. Evaluation of medium is attached green space which is good from the distribution of the ratio green space.But the distribution Characteristics of Landscape Patterns is scattered and uneven. Therefore, it has the lower level in the evaluation system. The worst of the comprehensive evaluation is green area for environmental protection and productive green space, both green space in Changsha City in terms of area, the distribution of landscape pattern indicators are poor and other areas, which need to transform the system to build of the green space in the future.Ecological service function:(1) The general trend of the change in single service function value of eco-system in Changsha between1996-2004can be describe as follow:gas regulation,climate regulation,water conservation,soil formation and erosion control, waste treatment, raw materials, biodiversity conservation, food production and recreational and cultural value have declined in number. Among them, the value of soil formation and protection, water conservation, climate regulation, waste treatment declined at the maximum range.(2) The total value of ecosystem services from1999to2009has decreased. The total value of ecosystem services (ESV) on total area in1996was1816.424×107yuan and it isl810.408×10'in2004, that is, during this period the value of ecosystem services has reduced6.016×10'yuan.(3) Depending on the spatial structure of different green space landscape pattern to analyze the impact of ecosystem services for:excellent spot pattern landscape of green space can significantly reduce the temperature, increasing relative humidity, reduced noise and lower atmospheric SO2, TSP pollution levels of pollutants. Among them, the cooling effect up to a significant level,To small and medium-size green space plaques and green corridor uniform distribution pattern of the environmental effects of green space can also be reflected in the dust-cooling and noise reduction on the humidifier. However, the cooling effect slightly stronger than excellent spot pattern landscape, and dust-noise reduction is much weaker than excellent spot pattern and scape.The results obtained from the above analysis:(1) The corridor of urban green space is Inadequate, especially the overall level of quantity and quality can't meet the require; simultaneity the grass system lacks a good layout and perfect quantize system. The main guideline is low and the arrangement of plants are not perfection. In addition,the quality of grass view is also low.(2) From the quantitative analysis of pattern elements, the urban green space system of Changsha show the green space landscape pattern which is mainly based on the giant plague, supplemented by the large,large-medium, small plague as well as the minor is medium plague. Yet the area of large plate occupy a dominant position, the number is rather rare, it's the weak landscape element of ecological pattern. From the analysis of dominance and fractional dimension of each block pattern, the small plague occupy a dominant position, but most is concentrated in the center area of the city, the degree of fragmentation is higher.(3) Different spatial scales of landscape pattern index changes have different reactions. Based on patch density, average area, fragmentation index results showed that the degree of landscape fragmentation increases as the particle size decreases, while the resolution increases with the size of the upward trend.(4) Through the analysis of four kinds results of Changsha City green space landscape spatial pattern and the air temperature, air relative humidity, ambient noise and atmospheric SO2,TSP levels and other environmental effects can be seen comparing observations, excellent spot pattern, the pattern of spots evenly, corridor pattern and control of4different types of landscape pattern in the total plaque area, plaque area and non-green building roads and other landscape areas on the overall pattern is more balanced(5) At the end of2009, the total population in Changsha is6417367, then it needs19251hm2green area, however, the green area at present is far less than the standard. And according to the balance of carbon and oxygen in city and the analysis of emission and absorption of so2, to maintain the oxygen balance,1694.62hm2broadleaf forest is must, but, if it want to absorb all so2, it will need868565.58hm2 broadleaf forest, there is a huge gap between them.This paper use the theory of fuzzy mathematics to evaluate Changsha urban green space system, analysing its landscape patterns and takes the changes in the landscape pattern as evaluation factors to study green space system regulation and the value of ecosystem services. These theories are cutting-edge theory in our country. This paper regard landscape ecology as guidelines and bring pattern of landscape ecology and ecosystem services into planning and design of urban green space in Changsha making various types of landscape features effective integration to achieve optimum system. It has an important significance in Changsha sustainable development of urban green space system and also for the construction of sub-tropical urban green space to provide reference.
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