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Aim: The deep waters around Iceland, known as the North Atlantic Gateway, constitute an ideal location to investigate deep-sea ecological hypotheses. We constructed a comprehensive deep-sea macroecological dataset of the North Atlantic Gateway region and investigated the controlling factors of large-scale, deep-sea species diversity patterns. Location: Sub-polar North Atlantic Ocean. Time period: Modern. Major taxa studied: Ostracoda (Crustacea). Methods: We investigated deep-sea biodiversity patterns and applied ecological modelling (multiple regression and model averaging) to test whether these patterns are governed by environmental factors such as temperature, surface primary productivity, and seasonality. Beta diversity analyses were applied to evaluate the effect of a geographical barrier (Greenland-Iceland-Faeroe Ridge) on deep-sea benthic faunal distributions. Results:We constructed a deep-sea macroecological dataset with 32 stations, 5,676 specimens, and >122 species. We confirmed a linear latitudinal diversity gradient with higher diversity in the North Atlantic proper than in the Nordic Seas. We report a unimodal depth diversity gradient south of the ridge, but a linear diversity-decline with depth north of the ridge. The turnover component of beta diversity increased towards the ridge. Main conclusions:We found both temperature and surface primary production are important for deep-sea biodiversity. For the first time, we report a significant diversity-temperature relationship in both macroecological (spatial; this study) and existing paleoecological (time-series) data for the same taxa. In addition to temperature and surface primary production, bathymetric features such as a shallow ridge acting as a barrier are an important factor for deep-sea biodiversity distribution. The low diversity of the Nordic Seas is likely due to a combination of low temperatures and bathymetric barriers. These results substantially expand our understanding of the | 2057 JÖST eT al.

Effective reef management and monitoring has become increasingly important as anthropogenic processes impact upon natural ecosystems. One locality that is under direct threat due to human activities is the Australian Great Barrier Reef (GBR). Marine foraminifera represent an abundant and readily applicable tool that can be used in reef studies to investigate a variety of ecological parameters and assist in understanding reef dynamics and influence management protocols. The first step is to establish a baseline knowledge of taxonomic composition within the region to facilitate comparative studies and monitor how assemblages change in order to maximise effective management. A detailed taxonomic assessment is provided of 133 species of benthic foraminifera in 76 genera from Heron Island, One Tree Island, Wistari and Sykes Reefs, which form the core of the Capricorn Group (CG) at the southern end of the GBR. Of these 133 species, 46% belong to the order Miliolida, 34% to Rotaliida, 7% to Textulariida, 5% to Lagenida, 3% to Lituolida, 3% to Spirillinida, 1% to Loftusiida and 1% to Robertinida. Samples were collected from a variety of shallow shelf reef environments including reef flat, lagoonal and channel environments. Seventy species, representing the most abundant forms, are formally described with detailed distribution data for the remaining 63 species supplied.

On March 11th, 2011 the Mw 9.0 2011 Tōhoku-Oki earthquake resulted in a tsunami which caused major devastation in coastal areas. Along the Japanese NE coast, tsunami waves reached maximum run-ups of 40 m, and travelled kilometers inland. Whereas devastation was clearly visible on land, underwater impact is much more difficult to assess. Here, we report unexpected results obtained during a research cruise targeting the seafloor off Shimokita (NE Japan), shortly (five months) after the disaster. The geography of the studied area is characterized by smooth coastline and a gradually descending shelf slope. Although high-energy tsunami waves caused major sediment reworking in shallow-water environments, investigated shelf ecosystems were characterized by surprisingly high benthic diversity and showed no evidence of mass mortality. Conversely, just beyond the shelf break, the benthic ecosystem was dominated by a low-diversity, opportunistic fauna indicating ongoing colonization of massive sand-bed deposits.