Landscape Pattern Change And Its Impact On Urban Heat Island In Beijing Urbanization

Urban ecosystem is different to natural ecosystems because it is human-oriented. Rapid urbanization has brought a lot of ecological and environmental problems to human being. A systemic research was conducted on ecological and environmental impacts of Beijing urbanization process based on landscape ecology. The main results of this study as follows:(1)Urban growth and characters of land use change of Beijing from 1984 to 2002 were reviewed. The urbanization level of Beijing raised significantly from 1984 to 2002, the fragmentation degree was also increased. From 1984 to 1991, there was an all-sided, massive urban expansion, and the urban area expansion took place mainly in areas 10km outside the city center from 1991 to 2002.(2)Urban heat island effect in Beijing was studied. Under the background of urban growth, urban heat island effect grew year by year. Newly added UHI(Urban Heat Island) regions nearly inosculated with newly built-up districts, strong heat islands have multiple centers. Common characters for the heat island areas are: lower green coverage, less water body, more buildings, population and sources of industrial heats were mustered.(3)Urban green space was analyzed in Beijing: it was lack of green coverage and has a tendency of fragmentating. The number of large, middle and small size green patches is disproportion.(4)Take all the above problems into consideration, some reasonable suggestions were proposed for setting up urban landscape pattern for ecological security in Beijing by taking urban heat island effect intensity as measurement for intensities of human disturbance (the flow of population, economical activities, metabolism of energy and materials) in urban ecological process, and by optimizing urban green space system as an approach to relieve human disturbance.