Report: » Beach snail Littorina littorea: Determination of intersex index; Coast of Lower Saxony (2008)»

At seven stations, beach snails (Littorina littorea) were collected at low water. Six of the stations are examined within the framework of the Federal-State Measuring Programme (BLMP). In addition to these BLMP sites, the Intersex Index (ISI) 2008 study was conducted at another station: Dornumer-Accumersiel port. The Borkum Port Henry and Norddeich Osthafen stations, which were also sampled previously, have not been investigated since 2008. The littorins were examined in accordance with the OSPAR guidelines. According to the classification system for biological effects of the EU Water Framework Directive, five ecological status classes are described on the basis of the ISI determined by the beach snail. In the report, the exact results are to be read.本研究于7个采样站位的低潮时段采集滨螺（Littorina littorea）。其中6个站位纳入联邦-州监测计划（Federal-State Measuring Programme，BLMP）的监测框架。除上述BLMP监测点位外，针对2008年雌雄同体指数（Intersex Index，ISI）的研究在另一个站位——多讷默-阿库默西尔港（Dornumer-Accumersiel port）开展。此前也曾开展采样的博克姆港亨利站（Borkum Port Henry）与北德奇东港区站（Norddeich Osthafen），自2008年起便未再进行调查。本次滨螺样本检测严格遵循OSPAR指南。依据欧盟水框架指令（EU Water Framework Directive）的生物效应分类体系，基于滨螺测得的ISI值，可划分出5种生态状态等级。具体精确结果请详见本报告。