13-8  Irrigation, Reservoirs, Flood Prevention, Water and Soil Conservation
Item	1990	1995	2000	2005	2010	2011
Number of Irrigated Areas at Year-end    (set)	5363	5562	5683	5860	5795	5824
33 000  Hectares and Over	72	74	101	117	131	129
20 000-33 000  Hectares	76	99	141	170	218	219
Effective Irrigated Area      (10 000 hectares)	2123.1	2249.9	2449.3	2641.9	2941.5	2974.8
33 000  Hectares and Over	604.7	631.4	788.3	1023.0	1091.8	1099.9
20 000-33 000  Hectares	189.6	244.4	344.0	408.0	474.0	479.6
Number of Reservoirs                            (unit)	83387	84775	85120	85108	87873	88605
Large Reservoir	366	387	420	470	552	567
Medium-sized Reservoir	2499	2593	2704	2934	3269	3346
Small Reservoir	80522	81795	81996	81704	84052	84692
Capacity of Reservoirs        (100 million cu.m)	4660	4797	5184	5624	7162	7201
Large Reservoir	3397	3493	3842	4197	5594	5602
Medium-sized Reservoir	690	719	746	826	930	954
Small Reservoir	573	585	594	602	638	645
Water-saving Irrigated Area (10 000 hectares)			1638.9	2133.8	2731.4	2917.9
Areas with Flood Prevention Measures	1933.7	2006.5	2098.9	2133.9	2169.2	2172.2
(10 000 hectares)
Area of Soil Erosion under Control	5300	6690	8096	9465	10680	10966
(10 000 hectares)
Total Length of Dikes                   (10 000 km)	22.0	24.7	27.0	27.7	29.4	30
Area of Land Protected by Dikes	3200.0	3060.9	3960.0	4412.0	4683.1	4595.6
(10 000 hectares)
a) The capacity of the large-scale reservoir is over 100 million cubic meters, while that of the medium-scale one is from 10 to 100 million cubic meters,
and that of the small-scale one is from 100 000 to 10 million cubic meters.