×≤ Figure 1 Average annual rainfall in China (as of average from 1956 to 1979)(source: Liu and Chen, 2001) Basin(Zone III) has a per capita water resource as low as 123.78 m/person/year. It is the water scarcest region in China and nowadays people depend on water trans- ferred from other basins, such as the Yangtze River Basin (Zone vD) through the South-to-North Diversion Project(Pan and Zhang, 2001), so the water withdrawal in this region is 251.57% of the internal water resource, as shown in Table 2. The per capita water resources in the Huai River Basin (Zone V) and Yellow River Basil (Zone IV) are also extremely low, and the water withdrawals take 88 and 82% of the internal water resources in the two basin igure 2 Main hydrological zones in China(source: Liu and Chen, 2001)Basin (Zone III) has a per capita water resource as low as 123.78 m3 /person/year. It is the water scarcest region in China and nowadays people depend on water trans￾ferred from other basins, such as the Yangtze River Basin (Zone VI) through the South-to-North Diversion Project (Pan and Zhang, 2001), so the water withdrawal in this region is 251.57% of the internal water resource, as shown in Table 2. The per capita water resources in the Huai River Basin (Zone V) and Yellow River Basin (Zone IV) are also extremely low, and the water withdrawals take 88 and 82% of the internal water resources in the two basins, respectively. Figure 2 Main hydrological zones in China (source: Liu and Chen, 2001) Figure 1 Average annual rainfall in China (as of average from 1956 to 1979) (source: Liu and Chen, 2001) X.C. Wang and P.K. Jin 37