Annual precipitationvariation coefficient was smaller in higher altitude mountain than in lower altitude areas and plain in Urumqi river basin.
年降水量变异系数随海拔的升高而减小，即海拔越高的区域降水量的年际间波动相对越小。
2
The runoff of Weihe river is extremely sensitive to precipitationvariation in Hulu river tributary valley, secondly to that in Bangsha river tributary valley.
葫芦河支流流域的降水量对径流量变化的影响最为敏感，其次是榜沙河支流流域的降水量。
3
Precipitation is a regionalized variable changing with the variation of space position. It has both random and structural properties.