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use/cover type. We calculated the area change ratio for the main 
land use type in the five series time periods(Tab.l). It can be 
seen from Tab.l that the area of cropland, woodland, and 
grassland were reducing continuously, whereas the construction 
land, water, and unused land area were increasing obviously. 
Change percent of the land for construction was the highest in 
the four comparison periods, It had been rising since the first 
studied period( 1977-1987) by 7.1%, and arrived at the top of 
10.8% in the forth period(2000-2005). The result is caused by 
growing population and urbanization. The population is dense 
and quickly increasing in Three Gorges Reservoir Area. It had 
grown from 14.8 million in 1992 to 20.0 million in 2004 (http: // 
www.3g.gov.cn). This growth in population and urbanization 
had increased the demand for food, houses, and factories (Hunter 
L M, 2004 and Semwal R L, 2005). Furthermore, The Three 
Gorges Project accelerated the regional economy, leading to the 
rapid rise in the use of construction land. 
Land use type 
1977-1987 
(%) 
1987 -1995 
(%) 
1995 -2000 
(%) 
2000-2005 
(%) 
Cropland 
-0.107 
-0.055 
-0.059 
-0.295 
Woodland 
-0.022 
-0.082 
-0.157 
-0.250 
Grass land 
-0.040 
-0.030 
-0.129 
-0.047 
Water land 
0.389 
0.090 
-0.551 
9.589 
Construction land 
7.104 
8.118 
14.471 
10.776 
Unused land 
0 
0 
1.312 
-7.371 
Table 1. the area ratio of land use / cover changes in Three Gorges Reservoir Area 
3.2 The Dynamic Degree of Land Type Area Change 
The dynamic degree of land type area change indicates the speed 
of annual land use area change, which is an important index to 
show change. It can describe the speed of LUCC in a certain 
region quantificationally. The calculation formula is 
D = A ‘ 2 ^ x—*—xl00% 
1 ^2 — fi 
Where A tl = area of a kind of land use type in time tl 
A,2 = area of a kind of land use type in time t2 
The results according to this formula are shown in Tab.2 
Land use type 
1977-1987 
(%) 
1987-1995 
(%) 
1995-2000 
(%) 
2000-2005 
(%) 
Cropland 
-0.011 
-0.008 
-0.012 
-0.059 
Woodland 
-0.002 
-0.012 
-0.031 
-0.050 
Grass land 
-0.004 
-0.004 
-0.026 
-0.009 
Water land 
0.039 
0.013 
-0.110 
1.918 
Construction land 
0.710 
1.160 
2.894 
2.155 
Unused land 
0 
0 
0.262 
-1.474 
Talbe 2. Dynamic degree of single land use in Three Gorges Reservoir Area 
From Tab.2, we can see in the four periods, cropland, forest, 
grass all reduced annually in a lower speed, however, the land 
for construction increased in a higher speed annually, and the 
change was accelerating continuously in every following period. 
For each type the most outstanding period is: 2000-2005 for 
cropland by 0.059, 2000-2005 for forest by 0.05%, 1995-2000 
for grass by 0.026%, 2000-2005 for water by 1.918%, 1995- 
2000 for construction by 2.894%, and 2000-2005 for unused 
land by 1.474%, which indicates that in third period and forth 
period (Three Gorges Project construction time) land use 
converted most rapidly. The main reason is the rising water line 
of Three Gorges dam. 
3.3 land transformation matrix 
Land transformation matrix is to show the pattern of changes, 
namely, from what to what. We made land transformation matrix 
in every time period to track the change. Limited by paper 
length , we took an example for 2000-2005 period in which the 
amount of land use changes was the greatest. The land 
transformation matrix during 2000-2005 was shown in Tab.3. 
Jn 
From 
Crop 
Wood 
Grass 
Urban 
Village 
Other 
built-up 
Water 
Unused 
land 
Cropland 
0 
0 
59.99 
5.25 
5.41 
0 
0 
Woodland 
0 
0 
9.68 
9.09 
4.87 
3.77 
0 
Grassland 
0 
0 
3.46 
4.88 
5.72 
7.30 
0 
Urban land 
0 
0 
0 
0 
0 
28.07 
0 
Village land 
0 
0 
0 
0 
0 
0 
0 
Other built-up 
0.22 
0 
11.77 
0 
0 
0 
0 
Water body 
0 
0 
1.53 
0 
0 
1.77 
0 
Unused land 
0 
0 
0 
0 
0 
0 
0 
Table 3. Land transformation matrix during 2000-2005