Table 1 Range of values for each grade and FR of DGSI.

Aspect (AS)

1

x < 0

0

0

2

0 ≦ x < 22.5

8

4.6

3

22.5 ≦ x < 67.5

24

13.8

4

67.5 ≦ x < 112.5

20

11.5

5

112.5 ≦ x < 157.5

17

9.8

6

157.5 ≦ x < 202.5

28

16.1

7

202.5 ≦ x < 247.5

20

11.5

8

247.5 ≦ x < 292.5

22

12.6

9

292.5 ≦ x < 337.5

25

14.4

10

337.5 ≦ x < 360

10

5.7

Curvature (CU)

1

–

80

46.0

2

0

0

0

3

+

94

54.0

Slope (SP)

1

x < 15

24

13.8

2

x < 30

95

54.6

3

x < 45

50

28.7

4

x < 60

5

2.9

5

60 ≦ x

0

0

TWI

1

x < 1.5

0

0

2

x < 3

32

18.4

3

x < 4.5

87

50.0

4

x < 6

41

23.6

5

x < 7.5

8

4.6

6

x < 9

2

1.1

7

x < 10.5

1

0.6

8

x < 12

1

0.6

9

x < 13.5

2

1.1

10

13.5 ≦ x

0

0

Tree diameter (TD)

1

None or rare

15

8.6

2

Small wood

34

19.5

3

Middle wood

119

68.4

4

Large wood

6

3.5

Parent rock (PR)

1

None

0

0

2

Igneous rock

93

53.5

3

Sedimentary rock

22

12.6

4

Metamorphic rock

59

33.9

Forest density (FD)

1

None

7

4.0

2

Low

8

4.6

3

Medium

9

5.2

4

High

150

86.2

Soil depth (SD)

1

0

0

0

2

x < 10

6

3.4

3

x < 20

43

24.7

4

x < 30

116

66.7

5

30 ≦ x

9

5.2

Forest type (FT)

1

None

1

0.5

2

Coniferous forest

73

42.0

3

Broadleaf forest

80

46.0

4

Mixed

20

11.5

5

Bamboo

0

0

Soil type (ST)

1

None

0

0

2

Sandy loam soil

107

61.6

3

loam soil

30

17.2

4

Silt loam soil

20

11.5

5

Silt clay loam

7

4.0

6

Sandy clay loam

6

3.4

7

Loamy sand

4

2.3

Drainage class (DC)

1

None

3

1.7

2

Poor

0

0

3

Ordinary

101

58.0

4

Good

64

36.9

5

Excellent

6

3.4

Accumulate form (AF)

1

None

7

4.0

2

Residual soils

61

35.1

3

Creep

92

52.9

4

Colluvial Soil

14

8.0