广西会仙湿地水质现状分析与评价

Analysis and evaluation of water quality status in Huixian wetland of Guangxi

为了解会仙湿地水环境质量的最新状况,对后续水体修复工作提供依据,于2017年4月和10月布点采样,对湿地水质现状进行分析,并采用综合污染指数法和营养状态指数法对湿地水体进行评价,结果表明:会仙湿地污染物时空分布特征明显,DO、Chl-a浓度枯水期显著高于丰水期,从湿地上游至下游呈上升趋势, TN和NH3-N浓度则呈下降趋势;湿地水体呈现不同程度的污染,其中运河河道达到严重污染水平,根据污染负荷分担率Ki值可知,TN(24.15~35.70)、 DO(3.97~38.71)和CODMn(9.86~25.80)对水体污染最为显著;各点位EI均值都大于50,会仙湿地水体整体处于富营养化状态。

Huixian wetland is the largest karst wetland in Guangxi. In order to understand water environmental quality of Huixian wetland and provide subsequent water remediation,this study sampled in April and October 2017,analyzed and assessed water environmental quality by comprehensive pollution index method and nutritional status index method. The results indicated that the temporal and spatial distribution characteristics of pollutants in Huixian wetland are obvious.The concentration of DO and Chl-a in dry season was significantly higher than that in high water season,and increased from the upstream to the downstream of the wetland, while the concentrations of TN and NH3-N showed a downward trend.The water of Huixian wetland were in different degrees of pollution, while ancient canal pollution was the worst. According to the analysis of the pollution loading(the value of Ki),TN(24.15-35.70)polluted water most seriously,followed by DO(3.97-38.71)and CODMn(9.86-25.80).The average value of EI was greater than 50 at every sampling site, so the water of Huixian wetland was in a eutrophic state.