Study On Phosphorus Contamination And Phosphorus Transportation Of The Yellow River In Lanzhou City

Phosphorus in water body would cause eutrophieation, which produces "Shuihua" in freshwater lake or river and gives birth to "Red Tide" in gulf or offing sea, the ecological equilibrium and economy development were greatly affected.there is great pragtical significance studying the phosphorus contamination of Lanzhou section of Huanghe River and related treatment technologies.For reflecting the phosphorus contaminates condition of Huanghe River after flowing throught Lan Zhou City, in this paper, thinking to traffic, taking samples condition and so on, selected Xincheng bridge section that Huanghe River entered Lanzhou downtown area and Yan erwan bridge that Huanghe River goes out of Lanzhou downtown area for monitoring, discussed the various forms of phosphorus content in Lanzhou section of the Yellow River water and analysed the correlativity of phosphorus content with the changing characteristics of surface water temperature,pH value,dissolved oxygen,etc.The results showed that the water quality of the Xincheng bridge and Yan erwan bridge both belong toⅢ, Xincheng bridge TP was 0.018-0.097mg/l,the annual average level was 0.042 mg/l,Yanerwan bridge TP was 0.04-0.105mg/l,the annual average level was 0.059mg/l;Soluble phosphate content of Xincheng bridge section in Yellow River water was 0.014-0.035mg/l and Yanerwan bridge section was 0.026-0.72mg/l;Soluble orthophosphate content of Xincheng bridge section in Yellow River water was 0.009-0.04mg/l,the annual average level was 0.023mg/l and Yanerwan section was 0.02-0.07mg/l, the annual average level was 0.042mg/l;In the winter and spring water soluble orthophosphate concentrations were higher, up to 0.07 mg/1.Transport fluxes of various forms of P in the two sections of Yellow River in Lanzhou City in 2007:(1)Xincheng bridge TP was 13.88×l0~2 t,Soluble phosphate content was 7.6×10~2 t, Soluble orthophosphate content was 7.6×10~2 t; (2)Yanerwan bridge TP was 19.49×10~2 t,Soluble phosphate contentwas 13.87×10~2 t, Soluble orthophosphate content was7.28×10~2 t. Transmission fluxes of phosphorus accross the Yanerwan bridge section were obviously higher than the Xincheng bridge section,TP was taller than out 28. 78% and Soluble phosphate content was taller than out 44. 85%, the result showed that transmission fluxes of phosphorus of the Yellow River in Lanzhou City were closely related with human production and daily life activities.Through analysising the relationship between the phosphorus content and the water surface temperature, pH, dissolved oxygen, conductivity, TDS, and other basic water quality parameters showed that: TP content with the temperature, pH value had a significant positive correlation, the correlation coefficient respectivelywas:(1)and the temperature: the Xincheng bridge section R=0.89515, the Yanerwan section R=0.59699; (2)andpH value: the Xincheng bridge sectionR=0.77078, the Yanerwan section R=0.65077; and with the flow,dissolved oxygen,conductivity had a significant negative correlation, the correlation coefficient were as follows:(1)and flow: Xincheng bridge section R=-0.77408, the Yanerwan section R=-0.60762; (2)and dissolved oxygen: Xincheng bridge sectionR=-0.45541; the Yanerwan sectionR=-0.40398; (3)and conductivity: Xincheng bridge sectionR=-0.59716, the Yanerwan section R=-0.47823.The relevant changes of soluble phosphates and soluble orthophosphate content changes with the flow, temperature, pH, dissolved oxygen, conductivity values, TDS were not highlighted.