| The land use/cover change, as the concrete forms that human activities affected the natural environment,is the key component and the main reason of global environmental change. It is also one of the main driving forces of natural environment change. Human activities affect the spatial pattern and process of natural environment through changing land use/cover. Wuhan is called "the Centre of Nine Provinces" in the history. With the process of gradually promoting of "the rising of the central China" and the authorized and implementing of Wuhan city circle as "the reform testing areas of national resources-saving and environment-neighboring social constructions with synthesis and whole set", significant variations will be taken place to land cover pattern. And it will have an profound influence on the regional natural environmental factors such as soil environment, water environment and climate environment. Thus, it is very important of study on land use/land cover change and its impacts on natural environment to the optimal allocation of soil and water resources, social economic sustainable development and natural eco-environment improvement.Based on the TM images of Mid of Eighties, mid of Nineties and early 21st Century and socio-economic statistic data etc., combination of field investigation, using 3S integration technique, the various data and information are corrected and handled scientifically. Using various means such as laboratory analysis, pattern recognition, model simulation and spatial calculation etc., we study on the dynamic process and driving factors of Hubei's land use / cover change in the past 20 years and put forward a typical partitioned mode, and apply cluster analysis to the land use/cover change of 11 typical cities (counties).Some predictions were done to analysis the most active land use change land category such as cultivated land, woodland and construction land. At the same time, this study discussed the effect of land use / cover change to soil erosion and soil quality combining with soil nutrient data and the remote sensing data of soil erosion. Using hydrology and water quality data, this study analysised the effect of land use/cover change to hydrological environment. And in this study we also discuss the climatic effects of land use/cover change combining with many years of meteorological and climate data. The main results are as follows:(1) In the past 20 years, significant changes were observed in the land use/cover of Hubei Province. During the years of 1985-1995, the order of the change range, from maximum to minimum, is cultivated land, woodland, waters, residential land, unutilized land, grassland. Cultivated land area obviously reduced among them. The order in the year 1996 to 2005 is unutilized land, waters, cultivated land, woodland, construction land, garden plot, grassland. The main tendency for the changes of land use/cover change in the past two decades is that cultivated land decreases gradually, while woodland shows an increasing trend, and construction land has a year-by-year-increasing trend.(2) It is apparent that the land use/cover change are caused by the interaction of various factors. The main reason of the decrease of cultivated land, the increase of waters owing to of fish pond, and the construction land expansion, is the explosion of population, the development of national economic, the low comparative benefit of cultivated land and flood disaster.(3) Hubei is divided into 4 class-1 regionalization, according to the present situation of society-economy-ecology, and 14 class-2 regionalization. Cluster analysis is employed to analysis the land use/cover change of 11 typical cities (counties) including Danjiangkou. The results showed that the Daye-led 6 cities (counties) has a increasing trend of construction land; Honghu which gives full play to its advantage of lake resource, as well as Zigui which is influenced by "large dams"in the area duing to increasing of waters; there is a leap of woodland and rapid reduction of cultivated land with a trend of one-falls-the-other-rises in Danjiangkou-led 3 cities (counties).As the remote sensing interpretation and statistical data say that the most actively change is the three categories of land as follows: cultivated land, woodland, construction land. The situation of Hubei (to 2010) is predicted by the application of grey forecasting model GM (1, 1). The result shows that the decreasing curve of cultivated land will much more stable while woodland will rise steadily and construction land will increase continuously.(4) Soil erosion displays a general downward trend in Hubei. The decrease rate of middle degree erosion and serious erosion is maximum. The change of land use type worsens the speed and intensity of soil erosion, furthermore, increases the amount of soil erosion. In the view of land category, the erosion area of cultivated land and woodland is the most, covering the 95.9 percent of total watershed erosion area.According to regional distribution, erosion intensity of West Mountain areas are the most, the next is central south areas. There was a good correlation between soil erosion and slope, most erosion are steep sloping field which 15 degree upwards.(5) The category change of land use effect the spatial heterogeneity of soil quality characteristics greatly. The different soil quality factors have different statistical variation in different depth. The order of these factors in the layer of 0～20 cm deep is available phosphorus, available potassium, TP,, TN, organic matter, TK, pH. The order in the layer of 20～100 cm deep, from max to min, is available phosphorus, organic matter, available potassium, TP, hydrolyzable nitrogen, TN, TK, pH. The pH of the whole region of Hubei Province appeared a little acidic, with the average being at 6.23 in the surface soil and 6.83 in the deep. The more sample depth increase, the more pH rise. The average content of organic matter of the whole province is relatively high; even surface soil can reach 1.926%. It show that the basic condition of Hubei's agriculture is a relatively good, the planting is comparatively developed. In the view of nugget-sill ratios, the pH of surface soil is the minimum 19.8%, others are no more than 50%. The results showed that the structural factor controlling of pH distribution leaded to the high intensity of spatial autocorrelation between sample points, while other factors showed medium intensity spatial autocorrelation.(6) The water resource is abundant in Hubei, but area of lakes and ponds declines sharply because of urbanization. Especially in regions with rapid economic development, water resources utilization is facing a serious situation. It's found by calculation that, there are quite serious problems about quantity of water and security in the east area of Hubei leading by Wuhan and the north area leading by Xiangfan at begin of 21st century. In the previous fifty years of 21st century, the consumption of living and production water will increase 10.16 billion stereos, which the rate is quite obvious, and only 1.04 billion stereos in posterior 50 years, which the rate slows down gradually. Land use/cover change is a main factor of floods in Hubei because of the following reasons. The urbanization process leads to increasing of surface runoff coefficient, blood becoming narrow and earlier. The existing mode of water discharge bring about waste and pollution of rain water. The urbanization process also causes eutrophication of lakes and river. And the influences of agriculture land use on water quality are as follows, chemical, fertilizer and pesticide pollution, livestock and poultry raising, living garbage pollution etc.(7) In recent 45 years, Hubei annual mean temperature is 15.9℃, which has rise 0.54℃and the rising speed is 0.12℃/10a. And the extreme maximum temperature showed a significant rising trend since 1980s. The urban heat island warming intension in capital Wuhan has strengthened in different season in recent 23 years. The annual mean precipitation is 1145.8mm in recent 45 years, which has a rising trend of 6.9mm/10a. The annual mean sunshine duration is 1749.9h, which has a obvious decreasing trend of -68.6H/10a. The increasing of heavy rainfall in recent years results in more flooding disaster.(8) The degeneration and recovering of the Jianghan plain wetland lead to local climate change. Since 1958, the annual mean temperature of the Jianghan plain has shown a trend of rising and the rising rate is 0.246℃/10a. But the temperature has begun to decrease obviously after 1998. The annual mean temperature decreased from 17.92℃in 1998 to 16.96℃nowadays and the rate is 0.4℃/a. Referring to the change of precipitation, it increased 4.9mm/a average since 1990s, especially in Sumer and Winter.(9) The urban environment temperature is closely related to such factors as underlying surface temperature, underlying surface structure difference, water body, vegetation cover and so on. As the change of land use due to the urbanization have extended great influence on the urban climate, the rapid acceleration of urbanization process lead to urban heat island effect of Wuhan increasingly. The seasonal difference about the rate of warming of the mean temperature, the maximum temperature and the minimum temperature from 1961 to 2000 was significant. Such conclusion was draw that a remarkable warming rate occurred in winter and the warming rate showed nonsymmetry in same season, which the warming rate of minimum temperature was highest, maximum temperature lowest and mean temperature between them. In recent two decades, the warming rate of mean, minimum and maximum temperature is raised in both urban and suburban in different season, and the warming rate due to the heat island obviously increased, especially maximum temperature in summer and minimum temperature in winter. The existing of urban heat island leads to the generation of the urban winds. And the urban winds is quite fit with the center of urban heat island in Wuhan.
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