转基因鲤鱼对大型底栖动物群落及多样性的影响

为了对转基因(CAgcGH)鲤的生态风险评估提供参考依据，于2004~2006年在梁子湖畔的人工隔离湖泊开展了转基因鲤对其主要饵料生物--底栖动物群落结构及多样性影响的研究。结果表明：投放转基因鲤1 a后，底栖动物物种组成、丰度和多样性指数均出现不同程度下降。底栖动物总物种数从65种下降为36种；总密度从4973 ind/m2下降到3707 ind/m2；总生物量(湿重)从77136 g/m2上升到97558 g/m2。单因素方差分析显示：总物种数、寡毛类、毛翅目和摇蚊科物种数有显著降低。寡毛类、毛翅目和腹足类密度有显著下降。毛翅目生物量有显著下降。幽蚊〖WTBX〗(Chaoborus 〖WTBZ〗sp.)和环棱螺〖WTBX〗(Bellamya 〖WTBZ〗sp.)取代纹沼螺(〖WTBX〗Parafossarulus striatulus)和苏氏尾鳃蚓(Branchiura sowerbyi)〖WTBZ〗成为优势种。底栖动物多样性呈现显著下降，3种多样性指数平均减少19%~44％，物种丰富度则减少了38%。〖WTBX〗K〖WTBZ〗优势曲线显示了同样结果。转基因鱼与对照鱼在捕食压力和摄食选择偏好上的差异，可能是造成隔离湖泊内底栖动物群落结构和多样性变化的重要原因之一.

EFFECTS OF ‘ALLFISH&rsquo|GH TRANSGENIC COMMON CARP 〖WTHX〗(CYPRINUS CARPIO L.) ON BENTHIC MACROINVERTEBRATE COMMUNITY STRUCTURE AND BIODIVERSITY IN THE ISOLATION LAKE

In order to evaluate the possible ecological risks of transgenic common carp,the present work primarily studied the effects of ‘allfish’ GH transgenic common carp (〖 Cyprinus carpio  L.) on benthic macroinvertebrate structure and biodiversity in an isolation lake during a two year period.The main results showed that species richness,abundance,the standing crops and biodiversity of the benthic macroinvertebrate community decreased at different degree after introducing of transgenic fish.The total species composition of benthic macroinvertebrate decreased from 65 to 36,total density from 4973ind/m2 to 3707 ind/m2.However,the total biomass (wet weight) increased from 77136 g/m2 to 97558 g/m2.One way AVONA indicated that taxa richness of Oligochaeta,Trichoptera and Chironomidae,density of Oligochaeta,Trichoptera and Gastropoda,and biomass of Trichoptera showed significantly decreased.Instead of  Parafossarulus striatulus  and  Branchiura sowerbyi,Chaoborus sp.and  Bellamya  sp.became the dominant taxa.Biodiversity indices (Margalef’s,Simpson and Shannon Wiener index) and species richness decreased 19%~44% and 38%,respectively and K dominate curves also showed that biodiversity decreased after introducing of transgenic fish.It might be true that the difference of pressure of predation,prey preference and prey size selection between transgenic fish and common carp play important roles in changing benthic macroinvertebrate community and biodiversity.However,further works should be carried out to conform to our preliminary result.