深圳市城市發展過程之生態環境影響與景觀格局最適化

Impacts of Urban Development on Ecological Environment and Landscape Optimization Strategies in Shenzhen

全球環境變化受自然環境與人類活動兩個方面因素影響，隨著都市化的過程不斷加快，人口大量聚集於機械化與工業化快速發展的都市地區，對於區域及全球環境帶來一定的影響，都市化所衍生的相關議題也成為研究全球環境變化的一個重要切入點。深圳市為大陸快速城市化地區之一，自1980年設立經濟特區迄今約30年，期間深圳市由原本的漁村發展成為今日大陸地區第三大城市。短時間，大範圍及高強度的開發建設雖帶來顯著的經濟效益，也帶來一定的生態環境影響。為了對深圳市近2,000km面積的土地進行時空變遷的分析，本研究結合遙感影像與土地利用現狀調查資料，分別針對景觀格局、植被覆蓋與熱環境變化三個面向，分析城市開發過程與植被退化及城市熱島等生態環境問題的空間關係；同時分析深圳市生態空間的組成與結構特徵。研究結果顯示：1990年以後的深圳市景觀出現快速變化，景觀破碎化現象主要表現在耕地面積及空間分佈的變化上，受到城建用地和閒置空間裸露地等的侵佔和道路等的分割，破碎化程度不斷加劇，其次則為林地。

As one of the most significant consequences of human activities, urbanization has caused enormous negative environmental impacts, from the local through to the regional and even global levels.To date, rapid urbanization and construction have created numerous ecological and environmental problems.Regarding its various dynamic processes, complicated driving anisms and ecological impacts, urbanization has become one ofthe key issues related to global changes such as land use change and climate change.Located in the Pearl River Delta, Shenzhen stands on the frontline of the Reformation and Opening of Mainland China.During the past 30 years, particularly Since 1990, the landscape of Shenzhen has changed from a traditional agricultural landscape to a typical urban landscape.Consequently, Shenzhen has blossomed into the third largest city in Mainland China.However, with the continuous growth in urban population and industry varcus environmental problems have begun to emerge w h negative impacts on the ur an ecoss sent indus study, spatial pattern changes of urban landscapes and the potential ecological impacts are assessed.First, spatial pattern of urban landscape has been extracted based on LANDSAT TM images and analyzed quantitatively with using a spatial analysis package embedded in geographical information system（GIS）platform Furthermore spatial modeling s applied to examine the effects of vegetation dynamics and urban heat island related to urban landscape changes, owing to urbanization, landscape fragmentation and urban heat island effect have been assessed to examine ters nfluence on natural vegetation degradation.The results indicate that rapid urbanization is speeding up the spatial changes of landscape pattern and degrading ecological function and environmental quality in Shenzhen, “The negative influence of urbanization on vegetation varies with landscape type.Area of agriculture landscape tends to decrease significantly, while natural landscape only changes slightly, that contribute to maintain a relatively high level of ecological service.Moreover, urbanization also affects lan d surface temperature.The result shows a remarkable rising trend of urban heat island effect since 1990. Especially, the most obvious temperature rise appears in the newly-built Meanwhile, the temperature is relatively low in the inner cities, which have well-developed urban aforesting and greening scheme, with evenly distributed green patches and closely spaced hgh-rise buildings.To mitigate the impacts of urbanization on urban environment, in 2005 the Shenzhen government devised a plan to integrate resource conservation areas, forest parks, and urban green lands（total area about 974 km）to establish a limited development area.From a network perspective, it is suggested that ecological planning in Shenzhen should construct an ecological network by enhancing the link between urtann open space and natural landscape in the and restricting urban expansion to reduce the impacts on the conser anon areas.