:Based on May to September weather cases during recent 10 years, together with the geographic information and the distri-
bution of hail storms weather and climate in Lanzhou,applying the products of the upper and surface observation and the numerical
weather prediction et al.,the weather forecasting methods for hail storms in Lanzhou are formed.The forecasting object is hail storms
at anywhere in the area, the principle is no failed forecast in 24 hours, the identification of the hail storms is according to methods of
the combination of the automation and man-computer interaction. These methods mainly provide the early warning and forecasting
information for hail prevention operation. We successfully forecasted two local hail processes by this operational forecasting system in
May in 2004, and the forecast accuracy reaches about 67%.

The main reasons for cultivation soil salted infarming irrigating regions of Hexi corridor are over flowing irrigation，string irrigation，non-leveling farmland，non-distributed irrigation，high volume of chemical fertilizer，unreasonable cultivation system，farming abandon and trench leakage.The countermeasures of prevention and cureare to level off farming land，to plant densely with reason， to increase the volume of organic fertilizer，to save water and prevent farming abandon.