| As a hotspot of urban ecosystem research, quantitative study on the urban landscape pattern and its ecological service value can be a solution to promoting urban sustainable development, which has practical value to improve urban ecological living environment. This dissertation attempts to introduce net primary production of vegetation into the evaluation of ecological service value of urban green space, in the meantime making a quantitative analysis on dynamic evolution and landscape pattern of ecosystem service value of urban green space so as to get the per unit area of ecological service value and temporal and spatial variation disciplines of different green space ecosystems. As a result, this study can make contribution to the research on sustainable development of urban ecosystem.This study classifies different types of green space ecosystems and analyzes some information on landscape pattern in research areas of four years (2003,2007,2010and2012), by collecting data from multi-period SPOT5and ZY-102C and by combining other data such as historical culture, meteorology and topography, statistic yearbook and field survey in Dalian City. This study spatialises the data of temperature, rainfall and total solar radiation and estimates net primary production of green space through the utilization efficiency model of solar energy, which aims to provide parameter for evaluation of ecological service value. This study also evaluates per unit area and total service value respectively in different ways, by combing the Digital Elevation Model (DEM) and by regarding eight types of ecosystem services as the basic service function of green space ecosystem. Main contents and conclusions of this research are as follows:(1) In recent ten years, the types of green space landscape in the main urban area in Dalian remain stable. Other green space and Public park are the primary green space types. The green spaces for research mainly locate in the hilly area in the southwest and southeast area. The green space areas account for large areas in Zhongshan and Shahekou districts, while green spaces in Ganjingzi district are extreme unevenly distributed. Regarding the types of green space landscape, the percentage of the density and area of manmade green space patches is on the increase and the index of the largest patches become higher, which shows that the landscape area expands and suffers from high degree of fragmentation; while the index of natural green space landscape become lower, which shows that human activities have great impact on it. In terms of the green space landscape level, the Largest Patches Index (LPI) and contagion index decrease while the Patches Density (PD) increases, which show that the types of green space patches tend to be fragmented and disjunctively distributed. However, the enlargement of spatial heterogeneity and the higher Shannon’s Diversity Index (SHDI) show that human-caused disturbance has been intensified. From the above analyses, in research area, the change of green space landscape pattern in recent ten years has weakened the natural features but enhanced the humanistic characteristics. By comparing the dynamic changes of main urban area and development area, we can know that the natural green space in main urban area has shrunk25.74%because of city construction and development from2003to2012, while the green space area in development area has become increased8.44%since2003. This shows that human decisions play an important role in the development of urban green space. In the city center to do isometric for3km buffer gradient zone, combined with landscape indices, its change was related to the hilly distribution of Other green space and part of Public park. The city center starts from the south and gradually expands northwards in the city, resulting in the volatility change of landscape index with the gradient.(2) In the four stages from2003to2012, the NPP average value of green space in the main area of Dalian increased15.72%in2007, but diminish12.5%afterwards. NPP total value had the same change trend, it increased13.67%in2007and diminsh13.41%aferwards. The same change trend in these two values could be best explained by the decrease of the total area of green space in the research areas. The max NPP is mainly distributed in the southwest and southeast, reflecting a general trend that the NPP in city center is lower than that in suburbs. From2003to2012, the areas with relatively lower NPP in research areas expand towards the city outskirts; higher in hilly areas, lower in plain areas which are manifested by the fact that the southwest and southeast of the city are significantly higher than the central and northern regions. According to relevant meteorological factors spatial distribution data, NPP spatial pattern is greatly influenced by the temperature and rainfall distribution. NPP is larger in the areas of higher rainfall, while NPP is smaller in the areas of higher temperature. Compared with temperature, rainfall impacts on NPP more.(3) Different service types of green space ecosystem value in research areas rank as follows:soil conservation service value, air conditioning service value, organic matter production service value, water reservation service value, nutrient accumulation service value, creature variety preservation service value, culture service value and waste disposal service value. Soil erosion in various types of green space ecosystem has relatively obvious changes in the four periods. In2010, due to the centralized rainfall, there is a large amount of soil erosion which is more likely to be found in land with complex curved surface morphology and relatively higher rainfall. The maximum total service value of green space ecosystem in research area is in the southwest and southeast, which are hilly areas, mainly covered by Other green space ecosystem. The minimum total service value of green space ecosystem in research area is in the centre and north of the city, which are mainly covered by artificial green space ecosystem. The spatial distribution gradually increases from city center to the peripheries. The green space area in southeast and southwest which are covered by Other and Public park is larger than that in center and north which have lots of construction land. Different types of green spaces in research area have different per unit area service value, ranking as Other green spaces, Public park, attached green space and road and river green spaces. The total value of four types of green space ecosystem service is consistent in eight kinds of ecosystem services, ranking as Other green spaces, Public park, attached green space and road and river green spaces. Other green spaces have been up to66.46%-79.52%of total service value, and Public park has been18.97%-25.09%of total service value. The total service value is greatly influenced by area. Overall, roads and river green space service value tends to increase. Public park, attached green space and Other green spaces increase before2010, whereas in2012they decline mainly due to the increase of artificial green space area and the decrease of natural green space area. |
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