生物操纵与非经典生物操纵的应用分析及对策探讨

分析了生物操纵(biomanipulation)和非经典生物操纵(non-traditional biomanipulation)理论的原理、应用条件及局限性,提出了在局部水体治理湖泊富营养化的对策.分析认为:生物操纵的核心内容是利用浮游动物控制藻类;但浮游动物不能有效控制丝状藻类和形成群体的蓝藻水华;我国的大型浅水湖泊浮游动物数量一般并不多,对浮游植物摄食压力不大;在浅水湖泊,浮游动物摄食藻类后很快分解、释放又进入物质循环,因此不能治理湖泊富营养化;浮游动物是浮游植物和鱼类等经济水生动物之间重要的营养通道,过分追求保护浮游动物是值得思考和研究的问题.而非经典生物操纵的核心内容是利用鱼类直接控制蓝藻水华;当鲢、鳙鱼达到阈值密度可以控制蓝藻水华,但很难控制所有藻类和降低N、P治理湖泊富营养化.在局部水体治理湖泊富营养化的对策是:把鱼类控藻、水生植被恢复和局部水域生态系统重建相结合,形成具有利用与控制蓝藻生产鱼类、吸收氮磷净化水质功能的"水质生物调控单元".

Analysis on biomanipulation,non-traditional biomanipulation and discussion of the coun-termeasures of biomanipulation application in waters

The principle, the application conditions and the localization of biomanipulation and non-traditional biomanipulation were analyzed. The countermeasure of biomanipulation of water quality was carried out in Lake Chaohu. The results were: The key mechanism of biomanipulation is to use zooplankton to control phytoplankton, but zooplankton can not effectively control filar alga and cyanobacterial blooms; generally, there are not plentiful zooplankton in large-scale shallow lakes, so the stress of zooplankton on alga is usually littler. Moreover, the alga fed by zooplankton grow more rapidly than before. Besides, zooplankton is the important energy path between alga and fishes which can not directly feed on alga, so zooplankton should not be protected excessively. However, The main content of non-traditional biomanipulation is that cyanobacterial blooms was controlled by silver carp and big- head. Silver carp and bighead are able to control cyanobacterial blooms only in threshold biomass, but can not control all kind of alga and reduce N and P. The countermeasure to deal with eutrophication in local area should be that the measurement such as non- traditional biomanipulation, restoration of aquatic vegetation and renewedly construct of ecosystem were combined into a unite which have the function of controlling cyanobacterial blooms to produce fishes and reducing N and P to depurate pollution water.