Trends of water quantity and water quality of the Yellow River from 1956 to 2009: implications for the effect of climate change

Abstract

Background: Based on the monthly data of river runoff and major ion contents of the mainstream of the Yellow River during the period of 1956–2009, the effects of climate change on the trends of water quantity and major ion contents have been analyzed. Results: The main conclusions have been drawn as follows: 1) The river runoff showed a significant decreasing trend from 1956 to 2009. 2) Total ion contents showed an increasing trend during this period, and there was a significantly negative correlation between the river runoff and total ion contents of the river. 3) There were two probable reasons for the increasing trends of major ion concentrations in the Yellow River. One was that the increasing of temperature caused by climate change enhances rock weathering; the other was that the decreasing trends of river runoff weaken its dilution effect for major ions in river water. Conclusions: The results obtained in this research implicates that climate change will affect the major ion chemistry and water quality of the Yellow River. Further researches are needed to study the effects of climate change on water quality and water environment.