厦门海域岩相海岸带疣荔枝螺(Thais clavigera)与甲虫螺(Cantharus cecillei)性畸变

Imposex of Thais clavigera and Cantharus cecillei in the coastal waters of Xiamen

海产腹足类性畸变以其对有机锡的敏感性、特异性和不可逆性而成为海洋有机锡污染的理想指示种。调查研究了厦门海域岩相海岸带疣荔枝螺(Thais clavigera)和甲虫螺(Cantharus cecillei)的性畸变情况,通过生物学指标IOI(性畸变率)、RPSI(相对阴茎发展指数)、VDSI(输精管发展指数)及SRI(性比指数)综合评价其性畸变发展程度,间接指示厦门周边海域的有机锡污染程度。研究结果发现,在采集疣荔枝螺的17个站点中有5个站点种群性畸变率为100%,其中宝珠屿种群性畸变程度最为严重,VDSI达4,采集甲虫螺的4个站点的种群性畸变率均为100%。性畸变程度较严重的种群普遍集中于厦门西港,并且表现出由港内到港外逐渐减轻的趋势,而白城、会展中心和大嶝岛等位于开阔的厦门东海域的种群性畸变程度最轻,与往年厦门西海域有机锡污染监测数据相比一致,体现出性畸变程度与有机锡污染程度及海港码头远近之间的相互关系。

The degree of imposex, i.e. the imposition of male characteristics onto females, in neogastropods can be used as a sensitive and accurate biomarker to evaluate organotin contamination in coastal marine environment. Now, the imposex status in females of Thais clavigera and Cantharus cecillei in 17 sites was investigated to evaluate the organotin contamination along Xiamen Bay during 2006 and 2007. The four indices including incidence of imposex（IOI） , relative penis size index （RPSI）, vas deferens sequences index（VDSI） and sex ratio index（SRI） were used comprehensively to assess the imposex status in order to ascertain the extent of organotin bioavailability in Xiamen Bay. Based on this research, T. clavigera in 5 sites and C. cecillei in all survey sites exhibited the IOI of 100%. At Bao ZhuYu Islet, the imposex level was the most serious with maximum VDSI value of 4. In general, the imposex level decreased from the inner to the outer of Xiamen Western Harbour, and the populations in the open Xiamen Eastern Waters including Bai Cheng, Convention and Exhibiton Center and Dadeng Island showed a lower imposex level. These results were accordant with the concentrations of organotins in 2005. The imposex degree also increased with increasing organotin contamination and decreasing distance from shipping facilities.