Man-made structures in the North Sea are known to act as artificial reefs by providing a habitat for sessile epifauna in a predominantly soft sediment environment. This epifauna is hypothesized to cast a so-called “shadow” over the soft sediment ecosystem by altering the nutrient composition in the overlying water column. In addition, the structure itself could alter currents and thereby influence the deposition and erosion of the sediments in the wake of the platform. This study aims to assess the long-term effects of a gas platform in the southern North Sea on the surrounding benthic community by both morphological and molecular identification of benthic species. The species composition and a set of abiotic factors of the sediment around a gas platform were assessed along four transects. Differences for the abiotic factors were found in the closer vicinity of the platform in the direction corresponding to the predominant currents. The number of benthic fauna families found in the molecular approach were on average three times higher than for the morphological approach. Both approaches showed that small differences occurred primarily due to changes in sedimentary organic matter content. Differences in species composition were more pronounced between transects rather than between distances from the platform.

中文翻译：

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人工结构对北海南部底栖生物群落组成的影响：通过形态学和分子方法评估

众所周知，北海的人造结构可在主要为软质沉积物的环境中为无栖的浮游动物提供栖息地，从而充当人工礁。据推测，这种动物群落通过改变上层水柱中的营养成分，在柔软的沉积物生态系统上投射出所谓的“影子”。此外，结构本身可能会改变电流，从而影响平台后的沉积物的沉积和侵蚀。本研究旨在通过对底栖生物的形态和分子鉴定，评估北海南部天然气平台对周围底栖生物的长期影响。沿着四个样带评估了天然气平台周围沉积物的物种组成和一系列非生物因素。在平台上更近的方向上，与主要水流对应的方向上发现了非生物因子的差异。在分子方法中发现的底栖动物类科平均比形态方法高出三倍。两种方法均显示出细微的差异主要是由于沉积有机质含量的变化。样点之间的物种组成差异更为明显，而不是距平台的距离之间的差异更大。两种方法均显示出细微的差异主要是由于沉积有机质含量的变化。样点之间的物种组成差异更为明显，而不是距平台的距离之间的差异更大。两种方法均显示出细微的差异主要是由于沉积有机质含量的变化。样点之间的物种组成差异更为明显，而不是距平台的距离之间的差异更大。