广州市流溪河降水离子浓度与电导率关系

通过对2006年7月～2008年5月在流溪河地区采集的106次降雨水样(雨量范围0.7～268.6 mm)进行化学测试,研究了降水中几类主要离子含量与电导率的关系.结果显示:(1)通过各化学离子含量计算的电导率与对应实测的电导率之间存在-2.94%的平均相对误差.(2)H~+离子浓度与电导率之间的相关关系,在水样中pH＜5.6时是正相关,在水样中pH≥5.6时呈现负相关规律.(3)电导率随离子总浓度的增加而增加,但当水样的总离子浓度相同或者H~+和总离子浓度相同时,由于样品之间存在显著的其他化学组成差异,致使电导率的不一样.(4)将水样分成pH≥5.6和pH＜5.6的两组后,每组中各离子浓度与电导率之间存在更好的回归关系,因此可以通过pH值、电导率的测定并利用刨归方程来预测水中的其他化学成分含量.

Relationships between electrical conductivity and main ions' concentration in rainwater at Liuxihe, Guangzhou

By the monitoring and chemical analysis of wet deposition at Liuxihe, Guangzhou, 106 rainwater samples with rainfall depth from 0.7 mm to 268.6 mm were collected and tested during the period from July, 2006 to May, 2008. The relationship between electrical conductivity (EC) and main ions' concentration in the precipitation was studied and discussed in this paper.The results indicated that: (1) Mean relative error between the measured data and the calculated data of EC was -2.94%. (2) The positive correlation between concentration of H~+ and EC was found in the rainwater with pH＜5.6 and the negative correlation occurred in the rainwater with pH≥5.6. (3) EC increased with the increase of total ions concentration, nevertheless, when the H~+ concentration and the total ions concentration were the same, there were also obvious EC differences among the rainwater samples duo to significant differences of chemical components. (4) After dividing rainwater into two groups (pH＜5.6 and pH≥5.6), there existed better relations between EC and ion concentrations, so the concentrations of some ions can be calculated or forecasted by the regression functions and the measured pH value and EC.