Henry Lea-Anne, Vad Johanne, Findlay Helen S, Murillo Javier, Milligan Rosanna, Roberts J Murray
Centre for Marine Biodiversity, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom.
cole Normale Supérieure de Paris, Département de Biologie, 46 rue d'Ulm, Paris, 75005, France.
Sci Rep. 2014 Jul 7;4:5589. doi: 10.1038/srep05589.
We present the first remotely operated vehicle investigation of megabenthic communities (1004-1695 m water depth) on the Hebrides Terrace Seamount (Northeast Atlantic). Conductivity-temperature-depth casts showed rapid light attenuation below the summit and an oceanographic regime on the flanks consistent with an internal tide, and high short-term variability in water temperature, salinity, light attenuation, aragonite and oxygen down to 1500 m deep. Minor changes in species composition (3-14%) were explained by changes in depth, substratum and oceanographic stability, whereas environmental variability explained substantially more variation in species richness (40-56%). Two peaks in species richness occurred, the first at 1300-1400 m where cooler Wyville Thomson Overflow Water (WTOW) mixes with subtropical gyre waters and the second at 1500-1600 m where WTOW mixes with subpolar mode waters. Our results suggest that internal tides, substrate heterogeneity and oceanographic interfaces may enhance biological diversity on this and adjacent seamounts in the Rockall Trough.
我们展示了对赫布里底群岛海台（东北大西洋）上的大型底栖生物群落（水深1004 - 1695米）进行的首次遥控潜水器调查。电导率 - 温度 - 深度测量显示，在海山顶部以下光线迅速衰减，侧翼的海洋学状况与内潮一致，并且在水深达1500米处，水温、盐度、光衰减、霰石和氧气存在高度短期变异性。物种组成的微小变化（3 - 14%）可由深度、基质和海洋学稳定性的变化来解释，而环境变异性对物种丰富度变化的解释程度要大得多（40 - 56%）。出现了两个物种丰富度峰值，第一个在1300 - 1400米处，较冷的怀维尔·汤姆森溢流（WTOW）与亚热带环流海水混合；第二个在1500 - 1600米处，WTOW与亚极地模态水混合。我们的结果表明，内潮、底物异质性和海洋学界面可能会增强罗科尔海槽中这座及相邻海山上的生物多样性。
