Table_2_On the Influence of Vulnerable Marine Ecosystem Habitats on Peracarid Crustacean Assemblages in the Northwest Atlantic Fisheries Organisation Regulatory Area.XLSX

Vulnerable marine ecosystems (VMEs) are considered hotspots of biodiversity and ecosystem functioning in the deep sea, but are also characterised by a high vulnerability to disturbance and a low recovery potential. Since 2006, a series of United Nations General Assembly (UNGA) resolutions have been developed, attempting to ensure the protection of VMEs in international waters. In the Northwest Atlantic Fisheries Organisation (NAFO) Regulatory Area, large areas of seabed have been closed to bottom-contact fishing to protect VMEs. However, knowledge of the influence of VME-indicator taxa on macrofaunal assemblages, and the appropriateness of current fishery closures for protecting macrofaunal biodiversity in this area is limited. Here we investigate relationships between the prevalence of VME-indicator taxa [poriferans (sponges), gorgonian corals, and pennatulaceans (sea pens)] and an extensive suite of peracarid crustacean biodiversity metrics in the NAFO Regulatory Area. We also examine whether the current NAFO VME closures protect areas of significantly elevated peracarid diversity. Of the VME-indicator taxa analysed, poriferans were found to have by far the greatest influence over peracarid assemblages. Assemblage structure was altered, and peracarid abundance, biomass, richness, diversity, and variability were enhanced in areas of elevated poriferan biomass, whilst assemblage evenness was slightly depressed in these areas. These findings reaffirm the perception of poriferans as crucial components of VMEs. In contrast, gorgonian coral density had little influence over the faunal assemblages investigated, perhaps reflecting their relatively low prevalence in the study area. Similarly, pennatulaceans were found to influence peracarid assemblages only weakly. This too may reflect a moderately low density of Pennatulacea in the study area. Our results highlight that the application of taxon distribution model outputs to ecological investigations and management decisions in data-limited environments should be treated with caution. Finally, our results indicate that the current system of fishery closures in the NAFO Regulatory Area may not be optimal in terms of providing adequate protection to VMEs against the impacts of bottom trawling.

脆弱海洋生态系统（Vulnerable Marine Ecosystems，VMEs）被视为深海生物多样性与生态系统功能的热点区域，但其同时兼具对干扰的高敏感性与极低的恢复潜力。自2006年起，联合国大会（United Nations General Assembly，UNGA）陆续通过一系列决议，旨在保障国际海域内脆弱海洋生态系统的保护工作。在西北大西洋渔业组织（Northwest Atlantic Fisheries Organisation，NAFO）管理区内，大片海底已被划定为底接触性捕捞禁渔区，以保护当地的脆弱海洋生态系统。然而，当前学界对于脆弱海洋生态系统指示类群对大型底栖动物群落的影响，以及现有禁渔措施对该区域大型底栖生物多样性的保护有效性的认知仍较为有限。本研究以NAFO管理区为研究区域，探究脆弱海洋生态系统指示类群[多孔动物（海绵）、柳珊瑚以及海笔]的分布丰度与一套全面的囊虾类甲壳动物生物多样性指标之间的关联。同时，本研究亦评估当前NAFO脆弱海洋生态系统禁渔区是否能够有效保护囊虾类多样性显著偏高的区域。在本次分析的脆弱海洋生态系统指示类群中，多孔动物对囊虾类群落的影响最为显著。在多孔动物生物量较高的区域，囊虾类群落结构发生改变，其丰度、生物量、物种丰富度、多样性及群落变异性均得到提升，而群落均匀度则略有下降。上述研究结果进一步证实了多孔动物作为脆弱海洋生态系统关键组成部分的地位。与之相反，柳珊瑚的种群密度对本次研究中的动物群落几乎无显著影响，这或许反映出该区域柳珊瑚的分布丰度相对较低。同理，海笔对囊虾类群落的影响同样微弱。这一结果同样可能与研究区域内海笔种群密度中等偏低有关。本研究结果提示，在数据受限的环境中，将类群分布模型的输出结果应用于生态研究与管理决策时需保持谨慎。最后，本研究结果表明，NAFO管理区内现行的禁渔体系在为脆弱海洋生态系统提供足够保护以抵御底拖网作业影响方面，或许并非最优方案。