春季盘溪河水质日变化规律及水质评价

2010年春季对盘溪河水质进行了采样监测,分析了春季盘溪河水质的日变化规律,运用非参数检验、方差分析和灰色关联度方法评价了盘溪河1 d内的水质变化情况.结果表明,盘溪河的t、DO、COD、Pb、Cd、Zn和Cu在上、中、下游都没有显著性差异(P>0.05),pH、EC、TP、TSS、BOD5、NO3--N、TN和NH4+-N表现出显著性差异;盘溪河各水质参数日变化情况差别较大,TN、TP和EC的日变化趋势在上游呈波浪式逐渐增加,中游波动较小,下游呈"单峰单谷"型,峰值出现在中午12:00.COD变化曲线呈"单峰"型,上游和中游峰值都出现在10:00,下游的峰值在12:00;盘溪河Pb、Cd、Zn和Cu的浓度较低,中游Pb、Cd、Zn和Cu浓度的峰值出现在12:00;运用灰色关联度方法评价了盘溪河水质级别:上游在18:00和20:00为劣Ⅴ类,其余各时间段河流水质为Ⅱ类;中游在12:00时水质为劣Ⅴ类,其余各时间段河流水质为Ⅱ类;下游各时间段水质均为劣Ⅴ类.

Diurnal Variation and Evaluation of Water Quality of Panxi River in Spring

Based on the investigation of water quality of Panxi River in spring, 2010, we assessed the diurnal variation of water quality in spring and the characteristics of water quality changes within a day by using non-parametric test, analysis of variance and grey relationship analysis. The results showed that the differences were not significant for t, DO, COD, Pb, Cd, Zn and Cu (P > 0.05) in upstream, midstream and downstream, but significant difference existed among the pH, EC, TP, TSS, BOD5, NO3(-) -N, TN and NH4(+) -N contents. The diurnal variation of different water quality parameters presented distinct patterns: TN, TP and EC increased wavelike with time in upstream, fluctuated less in middle and showed the "single-peak single-valley" pattern in downstream, with the peak at 12:00. The diurnal variation of COD showed that "single-peak" pattern and with the peak at 10:00 in upstream and midstream and peak at 12:00 in downstream. The concentrations of Pb, Cd, Zn and Cu were low and peak at 12:00 in midstream; The grey relationship analysis indicated that the water quality in upstream was inferior to the V class of surface water at 18:00 and 20:00 and were in the II class of surface water for the rest hours, and the water quality in midstream was inferior to the V class of surface water at 12:00 and were in the II class of surface water for the rest hours; and the water quality in downstream was inferior to the V class of surface water all time during investigation.