Analysis Of Urban Development And Environment Change In Anshun Based On GIS And RS

Cities of our country have entered a period of High speed develops in 1990's, especially with the suggestion and implement of the Western Development Project, The city is developing very fast, but meanwhile, the dilation of the city, the contraction of cultivated land and the greenbelt, the land's degeneration, have been directly changed the ecological environment in the area and then also affected the sustainable development of the society economy. The remote sensing technique has provided a convenient and rapid means for detecting covered land utilization changes and environment changes for urbanization develops.This research adopted the LANDSAT TM passes a remote sense of two times and the GIS technology, and to take the city development and environment changes from 1993 to 2001 in Guizhou An Shun City area as the object of the research, have dynamically monitored and analysed for the urbanization process and environment changes.Firstly to have Geometry adjusted, radiation rectified and noise disposed in An Shun downtown area for primitive remote sense portrait, and have used histogram to emphasis the image, and then have eliminated some part of shadow, all those have gotten great effect. By the principle of covering classification/land utilization, combining with the characteristic of covers/land utilization in An shun city, to have extracted a kind of landscape data form TM and ETM by the method of maximum likelihood. All the landscape types have been divided to 7 kinds types, such as the paddy field, dry land, forest, grassplot, water area, residential area and a use industrial and mining field.The research indicated that, after Guizhou Privince AnShun City entered the nineties, bigger change happened in land utilization/covering way with the fact that economic growth and the course of urbanization accelerating. From 1993 to 2001, the downtown of AnShun's paddy field, forest land, grassplot, unused field have decreased unceasingly, but dry land, construction use field increased. The dry land increased most, has increased by 17.95％between 8 years, but paddy field decreased most, has decreased by 9.96％during the 8 years, forest land also decreased very much, has reached 1459.73 hectare every year. The range of urban area expands outside unceasingly in this 8 years, the space of An Shun City expands very fast. In 2001 the scale of the city using field having expanded by almost 1/3 than in 1993, that expanded Shun City field-uses is mainly to invade and occupy cultivated land on each side. That have led to the AnShun City periphery vegetable field decreased unceasingly; however, development of the economy has brought about another problem, as increase of urban population, the need to vegetable and fruit is enlarged unceasingly, that led to while the paddy field falls off, dry land area is increasing.Because city land utilization types have being changed, lead to the changes of the face under the city, by analysis of the climate changes during the past 40 years in An Shun City, we have found that the trend of An Shun City climate changes is overall close to the countrywide, the extent of air temperature change is not notable during the past 40 years, the annual average air temperature is 14.06℃, apply the analyses of the linearity draft, the mean growth rate was 0.117℃, in every 10 years of An Shun City, great higher than Gui Yang City (0.045℃). But the trend of precipitation comes down, especially entered the nineties, decreasing trend change is greater than 30 years ago, with flood and waterlogging year. By the comparative analysis of the 40 years climate changes and entered the nineties climate changes, have discovered that after the nineties the An Shun downtown area climate environment change was accelerated, the air temperature rised, the trend of precipitation was especially obvious.In one aspect, the city heat island effect can reflect the urban environment change, this study from the picture of the heating power field distribution by urban area of An Shun City finds that the city dilation and the enterprise increasing have brought about the trend of the hot centre of An Shun downtown area moving to northwest. Combine the NDVI distribution picture of An Shun City we can see that, along with the dilation of the city to northwest direction, the vegetation covers decreased. See from the Space distribution picture of the heat island effect, in 1993, where the vegetation has covered higher, the city temperature is lower, but in the year of 2001, along with the coming down of the vegetation covers of the city, the heat island centre begins to shift toward the center of An Shun city, especially expands area of the city before 2001, The temperature going up obviously.During 8 years from 1993 to 2001, Land-use of An Shun City changed very quickly, part of Land-use types had bring big change, the city dilated rapidly, hot centre are expand to the city of dilation, environmental climate change obviously.