SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER
- Received Date: 2001-10-16
- Publish Date: 2001-12-20
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Key words:
- major ions /
- spectrum characteristic of water quality /
- water quality change /
- the Changjiang River
Abstract: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang (Yangtze) River, etc. The fluctuations of Ca2+, Mg2+ and HCO3- concentra tions in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation(QBO). Na+, Cl- SO42- have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn't exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river discharge fluctuation accounts for 43.9%,45.1%, 54. 3%, 33.9%, 30.3% and 42.7% of the variance of Ca2+, Mg2+, HCO3-, Na+, Cl-, SO42-, respectively, at Wuhan from 192 to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data.
Citation: | XIA Xing-hui, CHEN Jing-sheng, CAI Xu-yi. SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER[J]. Chinese Geographical Science, 2001, 11(4): 315-320. |