The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 
242 
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CONTAG 
X X 
(p.) /“ 
X*. 
z*. 
2 In m 
Where m = number of patch types (classes) 
Pi = proportion of the landscape occupied by patch 
type (class) i, 
g ik = number of adjacencies (joins) between pixels of 
patch types (classes) i and k. 
• Shannon diversity index (SHDI) 
m 
SHDI = Y,(Pi xLn P) (7) 
i=i 
Where Pi = proportion of the landscape occupied by patch 
type (class) i. 
• Modified Simpson's diversity index (MSIDI) 
MSID1 = -\r\Yj P i 2 (8) 
/=1 
Where Pi = proportion of the landscape occupied by patch 
type (class) i. 
• Shannon evenness index (SHEI) 
m 
YjPi xLn Pi 
SHEI = - (9) 
Lnm 
Where Pi = proportion of the landscape occupied by patch 
type (class i) 
m is number of patch types (classes). 
• Modified Simpson's evenness index (MSIEI) 
m 
-InX-ff 
MSIEI = (10) 
In m 
Where Pi = proportion of the landscape occupied by patch 
type (class i) 
m is number of patch types (classes) 
Landscape index 
year 
Grass land 
Farmland 
Construction land 
Woodland 
Water land 
Unused land 
Landscape 
1977 
0.0604 
0.0171 
0.0024 
0.0491 
0.0036 
0.0412 
0.1738 
PD 
1996 
0.0751 
0.1134 
0.1073 
0.0598 
0.0041 
0.0551 
0.4148 
2000 
0.0765 
0.1148 
0.0994 
0.0596 
0.0037 
0.0591 
0.413 
2006 
0.0949 
0.1013 
0.0662 
0.0635 
0.0107 
0.0675 
0.404 
1977 
1032.3618 
1224.1253 
36.0503 
116.5965 
968.9796 
181.0381 
575.4012 
MPS 
1996 
830.9357 
166.1222 
10.3887 
99.7627 
917.0495 
143.7226 
241.0636 
2000 
812.8416 
165.1289 
10.3396 
99.3936 
1274.8394 
121.988 
242.113 
2006 
624.8233 
201.6722 
11.4228 
102.2128 
475.3234 
117.8512 
247.5038 
1977 
9.9399 
3.8337 
0.057 
3.5426 
1.8848 
3.7504 
11.5042 
ED 
1996 
20.9804 
14.295 
1.6763 
4.9309 
2.1573 
5.0372 
24.5386 
2000 
21.0998 
14.1118 
1.532 
4.8889 
2.2434 
5.0225 
24.4492 
2006 
19.9437 
12.6308 
1.0374 
4.581 
2.1944 
5.0391 
22.7132 
1977 
40.0701 
25.5219 
5.7009 
47.521 
29.7752 
41.1095 
37.7611 
LSI 
1996 
79.1217 
97.8841 
46.8301 
63.0677 
32.7915 
53.5884 
76.1448 
2000 
81.1646 
96.3921 
44.5822 
62.8039 
30.5859 
56.0493 
75.9063 
2006 
81.7104 
83.3806 
35.2884 
56.7011 
28.7456 
53.4477 
70.7972 
1977 
34.8372 
6.6973 
0.0418 
0.6008 
1.2417 
1.9997 
34.8372 
LPI 
1996 
9.1917 
2.6185 
0.0593 
0.4186 
1.9565 
2.6494 
9.1917 
2000 
11.4713 
2.0707 
0.0559 
0.417 
3.2208 
1.8083 
11.4713 
2006 
16.9765 
2.0745 
0.0557 
0.9659 
2.6392 
2.604 
16.9765 
Table 2 Landscape pattern index in areas of cascade hydropower station construction 
The computed results of those indices are listed in Table 2. For 
the construction of cascade hydropower station, the original 
natural ecosystem was affected. The patch density of the 
grassland, farmland, woodland, water area and unused land 
increased steadily while the mean patch size decreased 
correspondingly, which accounted for fragmentation of these 
landscape types. The PD of the construction land dropped in the 
last ten years while the MPS went up recently, which indicated 
the ascending trend of connectivity and integrity of construction 
land. The Largest Patch Index (LPI) of water area has climbed 
rapidly, but as for the Mean Patch Size (MPS) of grassland, it 
has shown a decreasing tread, it can be explained that as the 
grassland patches were extensively distributed in the landscape 
around the water area, the rising of the water level because of 
the construction of the cascade hydropower station contributed 
to the fragmentation of the grassland. The LPI provided the 
information about the role the largest patch played in the total 
patches of the same land use. For the landscape change, the LPI 
of the water area, construction land, woodland and unused land 
climbed. The calculated LSI in the table did not fluctuate 
obviously, which suggested the reservoir construction did not 
change the patch shape intensively. 
Year 
CONTAG 
SHDI 
MSIDI 
SHEI 
MSIEI 
1977 
66.4342 
1.1025 
0.8157 
0.6153 
0.4553 
1996 
62.623 
1.1515 
0.8298 
0.6427 
0.4631 
2000 
62.4593 
1.158 
0.8351 
0.6463 
0.4661 
2006 
61.5337 
1.2013 
0.9001 
0.6705 
0.5024 
Table 3 Index comparisons of landscape diversity structure 
According to reviews of the regional landscape evolution, the 
Contagion Index (CONTAG) presents a declining trend while 
the landscape diversity indexes such as Shannon's Diversity 
Index (SHDI) rises, which implies that regional landscape 
patches turn to be more fragmented and the landscape had a 
trend of diversity and regularity surrounding the hydropower 
station field. The increased SHDI meant the diversity degree of 
each land use climbed up and centralized. The calculation of the