Using the microsoft access database system, a database of sandstorm in arid region in Northwest China has been created.
We designed system of data mining  (data mining machine), data maintaining ,data querying and data interface by C/S programming
structure under database environment. When normal user doesn't know data format ,the data mining machine can achieve data query-
ing and statistics according to any condition by visual interface ,and process data by all kinds of algorithms and come up with user
needful data SeqLIenCe.  Th1S  System Can Olltpllt qLICrylng TCSLI1tS by graph ,teXt flle ,mapplng flle and  SO On .The new data can he ap-
pended by the data maintaining system easily.

By using the data of monthly surface runoff of Shule，Heihe and Xiying rivers，and spring wheat yields in Zhangye，Jiuquan
and Wuwei regions more than 40 years，the impacts of the surface runoff of inland rivers on the spring wheat yields in Hexi region
were analyzed.The results show that the spring wheat yieldis increasing fluctuatly due to the development of irrigation，agricultural
technology and improved variety，additionally，it’s also impacted by the source of irrigation.The difference of runoff in spring could
lead to annual fluctuation of spring wheat yield，short-term fluctuation of annual runoff impacts on yield is small butlong-term
fluctuation is larger，especially the long tendency of runoff in spring decides measuring the amount of water inreservoirs，so it shows
that agricultural production is impacted by climate change.