郑州市某地面水源水体富营养化现状调查及相关因素分析

目的　了解水体富营养化状况及相关因素对富营养化的影响。方法　对郑州市某地面水源的两个采样点进行TN、TP、Chla、CODMn和SD连续三周的环境监测,并计算综合营养状态指数TLI(∑),根据地表水环境质量标准和湖泊富营养化评价与分级标准进行评价;同时对Chla与TN、TP、CODMn和SD进行两两因素的直线相关分析。结果　该地面水源两采样点TN均值分别为 1. 62mg/L和 1. 94mg/L,超过Ⅲ类标准 4. 40倍和 5. 47倍,TP均值分别为 0. 048mg/L和 0. 044mg/L,超过Ⅲ类标准 0. 92倍和 0. 76倍;SD均值分别为 1. 1m和 1. 2m,超过Ⅲ类标准 1. 27倍和 1. 17倍;Chla均值分别为 0. 006mg/L和 0.009mg/L,达Ⅲ级标准;CODMn均值均为 4mg/L,达Ⅱ级标准。两采样点TLI(∑)分别为 47. 32和 48. 96,水体处于中度营养状态。2号水样中Chla与TP呈正相关(r=0. 855　P<0. 05),与CODMn呈正相关(r=0. 841　P<0. 05),与SD呈负相关(r=-0. 871　P<0. 05)。水体氮磷比值为 20. 94~97. 35。结论　该地面水源水体氮磷污染严重,处于中度营养到富营养化的过渡阶段,影响Chla含量变化的主要因子有SD和TP。磷是富营养状态的限制性营养盐。

The Investigation and Analysis of the Eutrophic Condition and Correlated Factors of Some Surface Water Source in Zhengzhou

Objective To investate and analyze the eutrophic condition and correlated factors of some sureface wate source. Methodes several indices(TN,TP,Chla,COD Mn,SD,)were determined in two sampling stations by nine times sampling. The eutrophication degree was assessed with the synthetical Trophic Level Indexes of Chla, TP, TN, SD and COD Mn in two sampling sites. The influences of some environmental factors on eutrophication were analyzed via correlation analysis. Rusults The mean concentrations of TN,TP,Chla, COD Mnand SD in two sampling sites were 1.62 and 1.94 mg/L,0.048and 0.044mg/L,0.006and 0.009mg/L,4 and 4 mg/L,1.1and 1.2m respectively. TLI()of two sampling sites in the surface water source were about 50 which implyed the existence of eutrophication. Significant positive correlation were found between the Chla and TP (r=0.855 P<0.05),the Chla and COD MN(r=0.841 P<0.05),Significant negative correlation was found between the Chla and SD (r=-0.871 P<0.05).The concentration radio of TN to TP in the surface water source were about 20.94 to 97.35. Conclusions The surface water source was polluted by N and P seriously, the eutrophication is imminent. The main environmental factors affecting the concentration of Chla are SD and TP. Phosphorus is the potentially restrictive nutriment.