12-29 Irrigation, Reservoirs, Flood Prevention, Water and Soil Conservation and Improvement of Saline-Alkaline Land

Item

 

 

 

 

 

1985

1990

1995

1997

1998

 

 

 

 

 

 

 

 

 

 

 

Number of Irrigation Areas    (year-end)

5281

5363

5562

5579

5611

33 000  Hectares and Over

71

72

74

77

79

20 000-33 000  Hectares

66

76

99

115

114

Effective Irrigated Areas (10 000 hectares)

2077.7

2123.1

2249.9

2249.5

22746

33 000  Hectares and Over

599.6

604.7

631.4

640.8

669.1

20 000-33 000  Hectares

167

189.6

244.4

286.2

276.9

Number of Reservoirs

83219

83387

84775

84837

84994

Large

340

366

387

397

403

Medium-sized

2401

2499

2593

2634

2653

Small

80478

80522

81795

81806

81938

Capacity of Reservoirs (100 million cu.m)

4301

4660

4797

4583

4924

Large

3076

3397

3493

3267

3597

Medium-sized

661

690

719

729

736

Small

564

573

585

587

591

Watersaving Irrigated Areas (10 000 hectares)

 

 

 

 

1523.5

Jetting Irrigation

 

 

 

 

159.5

Dropping Irrigation

 

 

 

 

14.2

Pipeline Transportion

 

 

 

 

523.2

Flooded or Waterlogged Area

1858.4

1933.7

2006.5

2052.6

2068.1

Under Control        (10 000 hectares)

        

        

        

        

 

Area of Soil Erosion Under Control

4640

5300

6690

7224.2

7502.2

(10 000 hectares)

        

        

        

        

 

Improved Area of Saline-Alkaline Land

456.9

499.5

543.4

561.2

565.3

(10 000 hectares)

        

        

        

        

 

Total Length of Dikes       (10 000 km)

17.7

22

24.7

25.1

25.8

Area of Land Protected by Dikes

3106

3200

3060.9

3414.6

3629.0

(10 000 hectares)

        

        

         

        

        

 

 

 

 

 

 

a)The capacity of the large reservoirs is over 100 million cubic meters, while that of the medium ones is from 10 million to 100 million cubic meters, and that of the small ones is from 100 000 to 10 million cubic meters.