| The ecology environment is not only the basic condition for human survival and development but the foundation for socio-economic development. At present, with the acceleration of China's urbanization process and the improvement of industrialization level, the extensive economic growth is accompanied by the energy and resource shortages and the degradation of the environmental quality. Under the guidance of scientific concept of development, properly handling PRED (population, resources, environment and development) is fundamental for achieving sustainable development. Hangzhou is a well-known tourist city as well as a key national scenic tourist city famous for its historical and cultural heritages. In recent years, Hangzhou speeds up the urbanization level in the medium term, which significantly improves the economy growth, rapidly expands the scale of urban construction land, and increasingly boosts the standard of living of urban residents. However, rapid economic growth and fast urbanization process greatly change its natural landscape. With the economic development of the city, ecological environment deterioration impacts on the quality of the production and living environment for urban residents and has a negative effect on future development of urban economy environment to some extent. A city's competitiveness mainly depends on the quality of ecological environment. Therefore, how to solve the problem of urban ecological environment effectively during the urbanization is the fundamental guarantee for sustainable development. This paper studies the landscape pattern characteristics and its changing driver mechanism based on remote sensing image and GIS platform, meanwhile, the interaction mechanism between landscape pattern and ecological environment has been researched from the water, gas, heat environmental point of view and combined with statistics, monitoring and interpretation of remote sensing data. In this paper, the content and main conclusions are as follows:1. Landscape pattern characteristics and its driver mechanism of changingLand-use dynamic change and entropy analysis showed that from 1991 to 2005 nearly 15 years, Hangzhou's land-use changed significantly. Land-use information entropy goes upward with the acceleration of urbanization, the land information entropy change rate is 0.83 percent. Landscape pattern characteristic analysis showed that the total number of patch increased, the diversity of landscape went up, the degree of fragmentation of the landscape also went uptrend. The drop of patch dominance degree noted that the control of the advantage of big patch on the entire landscape was weakening with the land-use change. Landscape transferring analysis showed that agricultural landscape and water landscape reduced significantly during past 15 years, which is the main increasing source of urban construction landscape. The center of gravity analysis of agricultural landscape pattern changes showed that agricultural land area declined with the expansion of Hangzhou city, and the center of gravity of agricultural landscape shifts gradually from north to west. The driver mechanism study of landscape pattern change based on canonical correspondence analysis (CCA) showed that the gross national product and traffic density were the main driving factor for the landscape diversity (SHDI) and fragmentation (FN). Financial income and real estate investment are the main reasons for the increasing of the total number of patches (NP).2. Water environment spatial-temporal change and its relationship with urban landscape pattern Hangzhou water environment spatial-temporal change analysis showed that as a major urban water landscape, West Lake water quality was mainly affected by the total nitrogen (TN) and total phosphorus (TP) pollution, water quality of 5 monitoring points has improved from 1999 to 2003, but overall water quality needs further improving. Water quality monitoring of Qiantang River showed that the water quality decreased from the entrance of Qiantang River to the northern end of the canal, which was deteriorated by the production and life contamination along the canal. The relationship among the water quality, landscape composition and pattern has been researched by the method of buffer zone analysis. Finally, this paper constructed water quality environmental model (WQ) by stepwise regression. The model indicated that the canal water pollution was influenced by multi-dimensional impact forces, economy, population, urbanization and pollutant emissions of which were the main driving force for deterioration of the water. Meanwhile, the reducing water area led to a decline in water heavy load and water environmental capacity, which was also the indirect reason for water quality deterioration.3. Atmospheric environment spatial-temporal change and relationship with landscape patternThe sulphur dioxide (SO2), nitrogen dioxide (NO2) and total suspended dust (TSP) were chosen as atmospheric environmental assessment index in accordance with conventional evaluation index for Hangzhou city. On the whole, the air quality of Hangzhou city is in good level, and some air quality indicators, such as the concentration of suspended dust, dust, etc., are to further optimize, whereas the concentration of sulphur dioxide and oxides of nitrogen showed an upward trend, the air quality goes deterioration trend, and environmental quality should not be overly optimistic. The spatial distribution of air pollution concentration by geo-statistical method showed that the spatial distribution of three indicators of air pollution concentration has a similar nature, which was the low concentration of three indicators area in and around the West Lake scenic area. The air pollution index (API) goes gradually upward trend from southwest to northeast. In order to further reveal the relationship between spatial distribution pattern of air pollution concentration and change of landscape pattern, this paper analyzed the relationship between average value of each air pollution concentration indicator and landscape pattern indexes, respectively. Quantitative correlation analysis showed that there is a high coefficient among the largest green vegetation landscape patch area index (LPI-G), green patch of vegetation landscape fragmentation (FN2-G), construction landscape patch fragmentation (FN2-C) and NO2 concentration. The relationship between SO2 concentration and landscape pattern indexes is similar with that of NO2. But for TSP, only the largest building landscape patch area index (LPI-C) and construction landscape fragmentation (FN2-C) have a significant correlation with TSP. Some landscape pattern indexes of this paper used, such as landscape diversity and fragmentation of the landscape etc. have a weak correlation with all pollution factors. The study also showed that the change of landscape diversity is sensitive to pollution concentration, and has a significant correlation with it when the concentration of pollutants in the air reaches a certain value.4. Interactive mechanism between urban heat environment and landscape patternUrban surface temperature has been inversed and the heat market distribution has been accessed based on remote sensing images of the study area on the surface brightness temperature inversion. Urban surface-temperature changes have been researched based on analysis of profiles in different directions of city. Urban heat market changes difference analysis showed that urban development and its land-use patterns in different directions is complex and unsymmetrical.Urban heat field of environmental analysis showed that from 1991-2005 nearly 15 years, overall urban surface temperature went upward trend, and "heat island" scope expanded in different direction of the city from 1991 to 2005 nearly 15 years. The urban heat field performed the characteristics of expanding, scattering, associating and inter-decomposing. Finally, the study concluded that land-use landscape pattern characteristic is the determination mechanism for overall urban heat field distribution pattern. Furthermore, industrial layout and ecological planning and design are a push-resist mechanism for heat field distribution pattern, and the convergency of population and industry is an achieving mechanism for heat distribution pattern.5. Policy implications of the urban ecology environment effect changeThis paper proposes five-point regulation countermeasures of landscape pattern change and the ecological environment based on the qualitative and quantitative analysis of ecological environment in Hangzhou city. Firstly, to strengthen the governance and improve the investment in ecological environment is an important foundation. Secondly, to promote the industrial structure changing and the layout adjustment is the key. Thirdly, to improve the quality of urbanization is the fundamental way. Fourthly, to improve the level of implementation and management of land-use planning is the key. Lastly, to enact the ecological and environmental protection laws and regulations is guarantee.
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