该研究通过开展室内原位静态模拟试验,探讨了太湖梅梁湾常见优势种类羽摇蚊和长足摇蚊对底质环境以及内源释放的生物扰动效应,研究结果表明:2种幼虫均促进了沉积物的耗氧作用、显著降低了上覆水的溶氧量、促进沉积物中硝态氮向间隙水的溶出、促进沉积物氨氮向上覆水的释放;长足摇蚊促进了沉积物碱性磷酸酶活性和溶解反应性磷的溶出。2种摇蚊幼虫的物理扰动和生理代谢活动改变了泥水界面的氧化还原环境,促进沉积物的耗氧矿化作用,从而加速内源释放,对沉积物-间隙水营养盐的溶出和吸附平衡产生显著影响。
This paper studies the bioturbation of two dominant species i.e. Chironomus plumosus and Tanypus chinensis on benthic environment and inner loading release in Meiliang Bay of Lake Taihu by using simulative method in laboratory.Results indicated that both these two chironomids stimulated the sediment oxygen demand(SOD),significantly decreased dissolved oxygen in overlying water,stimulated nitrate dissolved from sediment to pore water and ammonia release to overlying water. Tanypus chinensis also significantly stimulated sediment APA and SRP release to pore water. The bioturbation and animal excretion of these two chironomids have changed the redox condition of the sediment-water interface,which led to stimulate the oxidised mineralisation,inner loading release and significant impact on the dissolution–absorption balance between sediment and intermediate water.