[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.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. z_qqian@163.com
Qian-Qian
QQ
Zhang
Xiao-Ke
XK
Wang
Li-Ling
LL
Hao
Fei
F
Lu
Zhi-Yun
ZY
Ouyang
Pei-Qiang
PQ
Hou
D002681:China; D002947:Cities; D004784:Environmental Monitoring; D045483:Rivers; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality
D014874:Water Pollutants, Chemical