An Analysis Of Periodic Rules Of The Elements Of Hydrology And Weather Of The Yellow River Source

The source region of the Yellow River is a very important part ofSanjiangyuan,a natural reserve,and one of the areas of the most seriouslyenvironmental degradation.So thoroughly studying of the region onevolutionary rules will play a very important role in recovering theecological environment of the region and the economic development inregions of the headwater region and the lower river.The article analysesprecipitation,temperature and runoffapplying wavelet theory.We foundthat there are periods of7-8 years and 3-4 years in the runoff.There maybe the period of 43-44 years in the runoffand it controls the whole trendofrunoff.The runofftakes on a track of low-high-low,and it resulted inthe runoff-breaking of 1960 and low water period and two times ofrunoff-breakings from 1995.The precipitation presents periods of 3—4years and 7-8 years.And the temperature shows a long period andperiods of 3—4 years and 7-8 years.From 50s to 90s,the temperature wentthrough a change ofhigh—low-high,and the area will be in high temperaturefrom 2000.In terms of the period of about 40 years,mnoff has an excellentrelativity,with temperature.SO considering long period(above 40 years),temperature is the chief factor affecting runoff but the short periodsof7-8 years and 3-4 years ofrunoffare resulted form precipitation.Thearticle deepens the cognition about the rules of ecological change inthe headwater region of Yellow River,reduces blindness and providesscientific reference to layout of the region.