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woodlands; 1986-2000, the order would become construction, 
lawn, unused land, farmland, woodland, water. From 2 periods 
of the changes, all the type of comprehensive dynamic content 
increased. ©The state index: in 1972-1986, the state index of 
construction land and farmland is closer to -1.00. It illustrated 
the input speed was big than the output speed of this two 
categories, internal two-way conversion have large area to turn 
out very few but very unbalanced states. The state index of 
Waters, woodland and undeveloped land was larger, were 
0 .97,0.83 and 0.76. Note that the output speed of the three 
kinds of categories is much larger than the input speed, size 
reduction, in the "cuts" state; Grassland index for the state was 
0.56, in a relatively unbalanced state, and the output speed was 
bigger than input speed. 1986-2000, construction sites than the 
output speed, extreme "expansion" state; Grassland index for 
the state was -0.38, describing its input speed was faster than 
output speed. Although lawn state of absolute index was small, 
its input speed and output speed was large, the internal two-way 
conversion obvious. In the State index greater than zero, the 
state index of unused land was close to 1.00. Note the output 
speed was bigger than input speed, many areas of the category 
turned into other categories; the state index of waters is 0.46, 
Note the output speed was bigger than input speed, which was 
the relative imbalance in the state; the state index of woodland 
and farmland were 0.16 and 0.18, closer to zero, the output 
speed was slightly bigger than the input speed, but both the two 
speeds were large, the internal two-way conversion Obviously, 
which was based on the t high turn in and turn out the 
circumstances of a state of equilibrium. 
4. ANALYSIS OF LAND USE / COVER DRIVING 
CHANGE FORCE IN THREE GORGES RESERVOIR 
AREA AT NEARLY 30 YEARS 
Land use / cover dynamically change of Three Gorges 
reservoir area affected by the natural elements and human 
factors at nearly 30 years. Policy, economic development, 
population and other human factors play a leading role, while 
climate, soil, topography and other natural elements were the 
minor. Following is the lead role of human factors analysis. 
4.1 policy-driven 
Nearly 30 years, the land use / cover change of Three Gorges 
reservoir area relatived with major national macro-policies. 
1970s to the 1980s, large-scale irrigation and water 
conservancy basically completed, and, since the 1950s and 
1960s large clearing, So in this time suitable for cultivation in 
the region have decreased, reducing land clearing, the farmland 
area increased to slow down; After the 1980s countries have 
implemented the upper reaches of the Yangtze River Water 
Conservation Forest, upper reaches of the Yangtze River 
Protection Project and the returning farmland to forest or 
grassland Project, the cultivated land on steep slopes of Three 
Gorges reservoir was part returned into woodland and grassland, 
the destruct of woodland and grassland were in a certain degree 
kept within limits; Meanwhile the mid-1990s after the progress 
of the Three Gorges Project is the most tense five years, the 
dam closure, the river closure, resettlement and urban relocation 
to varying degrees, causing a decrease in the amount of 
farmland. 
4.2 Economic development driven 
Three Gorges reservoir area is agricultural, 70's to the 80's as 
well as destroyed forest and wasteland in order to develop 
economic, But more appropriate or suitable for the cultivation 
of land has been rare, so 70's to the 80's cultivated area 
increasing trend towards relaxation; the late 1980s to the late 
1990s,with the economic development, people farming 
technology continues improved, also people began to 
understand improve farming land is not the only means of 
income, this means the use of farmland started increasing 
diversification, factories and construction sites of the increase 
was the main way. After the 1980s, particularly in 1997 after 
the establishment of Chongqing municipality, with Three 
Gorges reservoir area's rapid economic development, a large 
number of high quality arable lands were occupied for 
construction projects. 
4.3 Population growth drives 
The infection of population in the land use / cover change 
performs the change of the increase or minus in population lead 
to less food, clothing, shelter, transportation needs, population 
has been growing was one of the major pressure in regional 
sustainable development process, the conflict of high 
population density and the lack of per capita cultivated land of 
the Three Gorges reservoir area had become more prominent. 
70's to the mid-80, population increased, but the amount of land 
reclamation reduced, One can only cultivated at steep, but the 
growth rate slowed significantly; 1980s to 2000, construction 
sites have become increasing rapidly. The areas of cultivated 
land were occupied continue increased. Nearly 30 years, the 
population growth of reservoir was the important reason of the 
construction increasing sustained, rapid. 
5. RECOMMENDATION 
Analyzing the land use / cover changing of Three Gorges 
reservoir area from the mid-1970's to the end of last 
century ,nearly 30 years , could found that the reservoir quality 
of the ecological environment in urgent need of improvement. 
However, the ecological environment restoration and 
reconstruction has a long way to go, ensuring the upper reaches 
of the Yangtze River land sustainable use of resources, 
quickening the pace of the ecological environment restoration 
and reconstruction, given the following recommendations: 
(1) People should control the size of the population and 
improve the quality of population, develop the economy of the 
reservoir area. Three Gorges reservoir area had many people on 
too little land, coupling with the construction of the Three 
Gorges Project reservoir resettlement, Resettling 
Area returning farmland to forest and grassland in the 
implementation of the project, the obvious contradiction 
between people and land, for all the factors above should 
strictly control the size of the population; while the low quality 
of the population have resulted in a lack of backward 
technology, production methods primitive, the value of the 
ecological environment of ignorance for the development of 
chaos, extensive development, which should vigorously 
improve the quality of the population; In addition to the 
destruction of the ecological environment is largely caused by 
poverty, only to solve the problem of poverty in order to restore 
the ecological virtuous circle. 
(2) Scientific planning of urban construction, strictly control 
urban land. No one-sided pursuit of "high, and new and 
comprehensive", resulting in the building of things on too much, 
wasting a lot of land resources, This requirement will be strictly 
in accordance with the relevant regulations, strictly control the