13-10Irrigation, Reservoirs, Flood Prevention, Waterand Soil Conservation and Improvement of Saline-Alkaline Land
Item
1990
1995
2000
2002
2003
2004
Number of Irrigation Areas at the year-end(set)
5363
5562
5683
5691
5729
5800
33 000Hectares and Over
72
74
101
110
112
111
20 000-33 000Hectares
76
99
141
168
169
169
Effective Irrigated Areas
(10 000 hectares)
2123.1
2249.9
2449.3
2503.0
2524.4
2550.6
33 000Hectares and Over
604.7
631.4
788.3
915.8
938.1
971.4
20 000-33 000Hectares
189.6
244.4
344.0
407.2
408.4
405.7
Number of Reservoirs
83387
84775
85120
85288
85153
85160
Large
366
387
420
445
453
460
Medium-sized
2499
2593
2704
2781
2827
2869
Small
80522
81795
81996
82062
81873
81831
Capacity of Reservoirs
(100 million cu.m)
4660
4797
5184
5595
5658
5542
Large
3397
3493
3842
4229
4278
4147
Medium-sized
690
719
746
767
783
796
Small
573
585
594
597
597
599
Water-saving Irrigated Area(10 000 hectares)
1638.9
1862.7
1944.3
2034.6
Flooded or Waterlogged Area(10 000 hectares)
1933.7
2006.5
2098.9
2109.7
2113.9
2119.8
Area of Soil Erosion under Control
5300
6690
8096
8541
8971
9200
(10 000 hectares)
Improved Area of Saline-Alkaline Land
499.5
543.4
584.1
528.3
586.5
596.2
(10 000 hectares)
Total Length of Dikes
(10 000 km)
22.0
24.7
27.0
27.4
27.8
27.7
Area of Land Protected by Dikes
3200.0
3060.9
3960.0
4286.2
4387.5
4393.4
(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.กก
