In the tidal inlets of the northern Wadden Sea, species composition of selected taxa of the small benthos is compared to a study performed some 35 years before, using the same methods and sampling the same sites. Site-by-site comparisons suggest a dramatic change in community composition at a local scale. However, geomorphology is highly dynamic in this area, and sediment composition, water depth, or both, had changed during the intermediate decades in most of the sites. Since most of the species are limited to a single sediment type, a habitat approach was used for an alternative analysis of the data. This contradicted the idea of dramatic change but revealed relatively high stability of species composition at a regional scale, indicating that local change cannot be up-scaled to larger areas in this highly dynamic environment. Instead, a habitat approach is more adequate though increasing environmental dynamics requires increasing sampling effort. As a by-product of this study, 8 new taxa of Platyhelminthes are described: Karlingia septentrionalis n. sp., Paracalviria diadema n. sp., Kataplana macrobursalia n. sp., Adenorhynchus compositus n. sp., Litucivis simplex n. sp., Scoliopharyngea magnaspina n. sp., Promesostoma convolutum n. sp., and Gnathorhynchus rostellatus indivisus n. spp.

中文翻译：

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分析小底栖动物的长期变化：地貌动力学影响方法的选择

在瓦登海北部的潮汐进口处，将小底栖动物的选定分类群的物种组成与大约35年前进行的一项研究进行了比较，采用相同的方法并在相同的地点进行采样。逐个站点的比较表明，当地规模的社区组成发生了巨大变化。但是，该地区的地貌是高度动态的，在大多数地点的中间几十年中，沉积物成分，水深或两者都发生了变化。由于大多数物种仅限于单一沉积物类型，因此使用栖息地方法对数据进行替代分析。这与急剧变化的想法相矛盾，但是揭示了区域范围内物种组成的相对较高的稳定性，这表明在这种高度动态的环境中，局部变化无法扩大到更大的区域。代替，尽管不断增加的环境动态要求加大采样工作，但采用栖息地方法更为合适。作为这项研究的副产品，描述了8种侧柏的新分类群：Karlingia septentrionalis n。sp。，Paracalviria diadema n。sp。，大叶锦葵。sp。，Adenorhynchus compositus。sp。，单壳Litucivis simplex。sp。，Scoliopharyngea magnaspina n。sp。，Promesostoma convolutum。和Gnathorhynchus rostellatus indivisus n。spp。和Gnathorhynchus rostellatus indivisus n。spp。和Gnathorhynchus rostellatus indivisus n。spp。