长江荆江段的渔业生态环境评价

EVALUATION OF FISHERY ECOLOGICAL ENVIRONMENT IN THE JINGJIANG REACH OF THE YANGTZE RIVER

1997—2002年,对长江荆江段青、草、鲢、鳙产卵场的水环境质量和浮游生物状况进行了调查,并用河流水质综合评价方法和Kolkwitz&Marsson体系法进行了评价。结果表明:在每年5—6月份的青、草、鲢、鳙繁殖季节,仅个别采样点铜或石油类超过渔业水质标准,该江段水质基本符合渔业水质标准和地表水环境质量Ⅱ类标准,能满足青、草、鲢、鳙繁殖对水质质量的要求。浮游生物的指示性表明其水体属于β中污带。

Jingjiang reach of the Yangtze River is an important spawning site for four major Chinese carps. In order to assess the water quality and the suitability for four major Chinese carps to spawn, investigations focused on this site were carried out from 1997 to 2002. The water from 3 sampling stations were monitored for 17 physico-chemical parameters （temperature, pH, dissolved oxygen, permanganate index, ammonium, total phosphorus, volatile phenolic, oil, total cyanide, chromium, Cu, Zu, Pb, Cd, Hg and As）. Additionally ,the species and density of plankton were also measured .They were then evaluated by applying comprehensive assessment method of river water quality, the Kolkwitz ＆ Marsson system. The results were as follows： Water quality was fit for four major Chinese carps to spawn. For it was about Ⅱ grade according to the environmental quality standards for surface water, and only at few sampling sites, the copper or oil in water was higher than the content of the criterion of water quality for fisheries. According to the results of investigation on the plankton, water in Jingjiang reach of the Yangtze river is polluted to certain extent and is allocated to β middle polluted zone.