An international team including Dr hab. Tomasz Niedzielski of the Institute of Geography and Regional Development of the University of Wrocław, recipient of a HOMING PLUS programme award, has announced the results of an eight-year study on the Mid-Atlantic Ridge in the prestigious scientific journal PLOS ONE. These results show that the role of the ridge in the concentration of submarine life in the area is less significant than previously thought.
The Mid-Atlantic Ridge, a submarine mountain chain stretching from Iceland to Antarctica, is the longest mid-ocean ridge in the world. Such ridges mark the boundaries between tectonic plates, with the magma that reaches the surface resulting in the creation of new rocks. In the formation of the ocean floor, mid-ocean ridges stand out as high mountains above the submarine plains, also known as abyssal plains.
The results of the research show that the increased biological productivity at the Mid-Atlantic Ridge corresponds to the same concentration of organisms in the water column as if the ridge were not there. Although the team discovered new species during the research voyages to the Mid-Atlantic Ridge area, the scientists demonstrated that most of them also occur at similar depths at the continental slope near the ocean edge.
The work also included new results concerning a quantitative assessment of the influence of the Mid-Atlantic Ridge on the Atlantic’s surface currents and sea fronts. In fact, the situation and dynamic of the subpolar front has a major significance for ocean life, including at great depths.
The research took place as part of the ECOMAR (Ecosystems of the Mid-Atlantic Ridge at the Sub-Polar Front and Charlie-Gibbs Fracture Zone) project under the direction of Prof. Imants Priede of the University of Aberdeen (UK). The 38-person interdisciplinary team was made up of scientists from 19 renowned universities and research institutes from nine countries. The fieldwork was carried out in the North Atlantic area over the course of several scientific voyages on research ships, from which unmanned submarine robots and underwater landers were sent towards the ocean bed. Processing of the various data – including a detailed topography of the seabed, high-resolution photographs of it, the direction and speed of currents around the ocean floor, biomasses and genetic characteristics of organisms and samples of seabed deposits – took place in various institutions, often based on integration with other available sources of data on the ocean, such as global bathymetry and satellite altimetry observations.
Dr Tomasz Niedzielski was responsible for conducting spatial analyses in the geographic information systems, and especially for modelling the relations between ocean depth and biomass. He developed a collection of new maps of the seabed of selected areas of the North Atlantic, with a resolution of approx. 100 m. His contribution to the fieldwork comprised preparation of a personal geoinformation system supporting the navigation of a submarine robot. This system was based on reproduction of data from sonars installed on this submarine equipment.
Photo caption: Crossota – a type of jellyfish occurring in the studied deep-sea environment (photo: David Shale).