潇湘平湖水质污染及其对鱼类影响的研究

Water Pollution and its Effects on the Fishes in Xiaoxiang Lake

对潇湘平湖菜市、曲河、宋家州3湖段水质及其对鱼类毒性影响进行了调查研究:⑴潇湘平湖水质已受石油烃类、挥发酚类、重金属铜和氨氮为主的污染源的污染,尤其是氨氮污染严重,污染程度宋家州>曲河>菜市。污染物中的石油烃类、挥发酚类、重金属Pb、Cu和As在鲤、鳊、鳜、黄颡鱼、草鱼和翘嘴鲌体内有一定蓄积,超过参考值8.03、1.66、1.30、1.71、1.24倍;肉食性鱼类较草食性鱼类高,石油烃类含量肉食性鱼显著高于草食性鱼(P<0.05)。⑵经t检验,试验组鱼类染色体微核率与对照组比较,差异显著(P<0.05)。⑶3湖段共有浮游植物6门43属85种,其中污染指示属18属,耐污染的普通等片藻、小异端藻等16个属出现频率较高;浮游动物3门8属14种,底栖动物3门3属3种,其中污染指示生物颤蚓1458.67条/m2。污染指示属宋家州>曲河>菜市,宋家州显著高于菜市(P<0.05),多样性指数的计算值表明:从菜市至宋家州湖段的依次为2.35、2.13、1.67,表明宋家州段的水质受到中度污染;菜市、曲河段水质已轻度污染。

Water pollution and its effects on the fishes were investigated at Caishi, Quhe and Songjiazhou regions in Xiaoxiang Lake. The results showed that water quality in these sections had primarily been polluted to some extent by petroleum hydrocarbon, volatile phenols, Cu and especially NH3-N. The Songjiazhou was the most polluted area, heavily,followed by Quhe, then Caishi. Petroleum hydrocarbon, volatile phenols, Pb, Cu and As deposited in fishes such as common carp （Cyprinus carpio）, white bream （Parabramis pekinensis）, mandarinfish （Siniperca chuatsi）, yellow catfish （Pelteobagrus fulvidraco）, grass carp （Ctenopharyngodon idellus） and topmouth culter （Erythroculter ilishaeformis）. The accumulated content of petroleum hydrocarbon, volatile phenols, Pb, Cu and As was 8.03, 1.66, 1.30, 1.71 and 1.24 times as much as reference indexes, respectively. Yet, there were more pollution deposits in carnivorous fish than those in herbivorous fishes, however, there were much higher deposits of petroleum hydrocarbon, in carnivorous fishes than those in herbivorous fishes （ P 〈0.05）. A t- test showed that there was significant difference in micro-nucleus rate between tested and control groups （ P 〈 0.05）. There were 85 phytoplankton species belonging to 6 phyla and 43 genera including 18 poison-indicator genera, 16 poison-resisting genera such as Diatoma rulgare and Gomphonewa parvunum, and 14 zooplankton species belonging to 3 plyla and 8 genera, and 3 zoobentho species belonging to 3 plyla and 3 genera including 1458.67 Limnodrilus/m^2 in the three sections. There were more poison-indicator genera in Songiiazhou than in Quhe and Caisi （ P 〈 0.05）. Multiple indices showed that the water was heavily polluted in Songjiazhou section, and lightly in Caishi and Quhe, with index of 2.35, 2.13 and 1.67, respectively.