Study of Temporal Dynamics on Ecological Types of Land during Shanghai Urban Development
|School||Shanghai Normal University|
|Keywords||ecological land types shanghai spatial and temporaldynamics|
The expansion of the city is the transformation of natural environment into a human environment, with the gradualreplacement of natural underlying surfaces by impervious pavement surface. The land area of farmland, green space water, and other ecological land, as the basic resource forcity development, is increasingly reducing. The previous land use planning was paralleled conducted with the urban development planning, neglecting the change of land type, the balance between development and stability in the process of urban development, and therefore, to some extent, affected the overall urban development.This paper focused on the eco-environment perspective of land ecological types in the process of urban development. Landsat TM digital images of1987,1997, and2007were used to establish the modeling of such index as brightness, temperature of the ground, and green space area, and therefore, on the perspective of greenness and heat, to quantify the ecological effect. On the basis of such modeling and ecological index, land area was separated into thermal zone, thermalgreen zone, green zone, and the watergreen zone. Finally, the research on the temporal and spatial change of land ecological types in past two decades in Shanghai was conducted, to reach following conclusion:(1) The hot zone, which refers to the urban land, continues to expand, but the land scale of central urban and suburban areas still remains at low level, and no reasonable structure of’multi-core’and ’multi-axis’is established.(2) The thermal green zone, which refers to the transitional land between urban and suburban area, accounts forthe biggest function land type, surpassing the area of farming land and suburban land. (3) The green zone, which refers to the farming land, represents highdynamic level. Land use intensity of some rural land, especially thejunction zone between urban and development area, is relatively low.(4) The water green zone, which refers to water and wet land area,remains at low level in the past two decades with no synchronizationwith the development of the city.