Abundance and biomass of the benthic infauna of the North Sea

In 1986 participants of the Benthos Ecology Working Group of ICES conducted a synoptic mapping of the infauna of the southern and central North Sea. Together with a mapping of the infauna of the northern North Sea by Eleftheriou and Basford (1989, doi:10.1017/S0025315400049158) this provides the database for the description of the benthic infauna of the whole North Sea in this paper. Division of the infauna into assemblages by TWINSPAN analysis separated northern assemblages from southern assemblages along the 70 m depth contour. Assemblages were further separated by the 30, 50 m and 100 m depth contour as well as by the sediment type. In addition to widely distributed species, cold water species do not occur further south than the northern edge of the Dogger Bank, which corresponds to the 50 m depth contour. Warm water species were not found north of the 100 m depth contour. Some species occur on all types of sediment but most are restricted to a special sediment and therefore these species are limited in their distribution. The factors structuring species distributions and assemblages seem to be temperature, the influence of different water masses, e.g. Atlantic water, the type of sediment and the food supply to the benthos.1986年，国际海洋考察理事会（ICES）底栖生态学工作组的参与者对北海南部与中部海域的底内动物（infauna）开展了同步调查制图。结合Eleftheriou与Basford（1989，DOI:10.1017/S0025315400049158）针对北海北部底内动物的调查制图成果，本研究构建了可用于完整描述全北海底栖内栖生物群落的数据库。通过双向指示种分析（TWINSPAN）对底内动物进行群落划分后，沿70米等深线可清晰区分北部群落与南部群落。 群落还可进一步通过30米、50米及100米等深线，以及沉积物类型进行细分。除广泛分布的物种外，冷水物种的分布南界不超过多格滩（Dogger Bank）北缘，该边界与50米等深线基本吻合。暖水物种则未在100米等深线以北海域被观测到。部分物种可在所有类型的沉积物中存活，但多数物种仅局限于特定类型的沉积物生境，因此其分布范围也受到严格限制。调控物种分布与群落结构的核心影响因素似乎包括水温、不同水团（如大西洋水团）的作用、沉积物类型以及底栖生物的食物供给。