Scottish Association for Marine Science

About: Scottish Association for Marine Science is a facility organization based out in Oban, United Kingdom. It is known for research contribution in the topics: Sea ice & Benthic zone. The organization has 524 authors who have published 1765 publications receiving 70783 citations. The organization is also known as: SAMS & Scottish Marine Station for Scientific Research.

Polyphyletic origin of the dictyosphaerium morphotype within chlorellaceae (trebouxiophyceae)

Abstract: The green algal Dictyosphaerium morphotype is characterized by spherical or oval cells connected by gelatinized strands to microscopic colonies, which are covered by prominent mucilaginous envelopes Combined SSU and ITS rRNA gene sequence analyses revealed that this morphotype evolved independently both in the Chlorella and Parachlorella clades of the Chlorellaceae It was shown that strains exhibiting the morphology of the type species Dictyosphaerium ehrenbergianum Nageli established a sister lineage to Parachlorella The strain D ehrenbergianum CCAP 222/1A was designated as an authentic strain for establishing the epitype of the genus Dictyosphaerium The comparison of this strain with the authentic strain of Parachlorella beijerinckii Krienitz, E Hegewald, Hepperle, V Huss, T Rohr et M Wolf (SAG 2046) showed considerable differences in the secondary structure of the ITS region Within the whole ITS-1 and ITS-2 region, 27 compensatory base changes (CBCs) were recognized In the conserved Helix III of the ITS-2, five CBCs/HemiCBCs were detected This is a conclusive argument for separation of these two species The clear definition of Dictyosphaerium is intended to be the necessary starting point of taxonomic reevaluation of Dictyosphaerium-like algae within different evolutionary lineages of the Chlorellaceae

Multi-scale interactions between local hydrography, seabed topography, and community assembly on cold-water coral reefs

Abstract: We investigated how interactions between hydrography, topography and species ecology influence the assembly of species and functional traits across multiple spatial scales of a cold-water coral reef seascape. In a novel approach for these ecosystems, we used a spatially resolved complex three-dimensional flow model of hydrography to help explain assembly patterns. Forward-selection of distance-based Moran's eigenvector mapping (dbMEM) variables identified two submodels of spatial scales at which communities change: broad-scale (across reef) and fine-scale (within reef). Variance partitioning identified bathymetric and hydrographic gradients important in creating broad-scale assembly of species and traits. In contrast, fine-scale assembly was related more to processes that created spatially autocorrelated patches of fauna, such as philopatric recruitment in sessile fauna, and social interactions and food supply in scavenging detritivores and mobile predators. Our study shows how habitat modification of reef connectivity and hydrography by bottom fishing and renewable energy installations could alter the structure and function of an entire cold-water coral reef seascape.

Benthic Assemblages of the Anton Dohrn Seamount (NE Atlantic): Defining Deep-Sea Biotopes to Support Habitat Mapping and Management Efforts with a Focus on Vulnerable Marine Ecosystems

Abstract: In 2009 the NW and SE flanks of Anton Dohrn Seamount were surveyed using multibeam echosounder and video ground-truthing to characterise megabenthic biological assemblages (biotopes) and assess those which clearly adhere to the definition of Vulnerable Marine Ecosystems, for use in habitat mapping. A combination of multivariate analysis of still imagery and video ground-truthing defined 13 comprehensive descriptions of biotopes that function as mapping units in an applied context. The data reveals that the NW and SE sides of Anton Dohrn Seamount (ADS) are topographically complex and harbour diverse biological assemblages, some of which agree with current definitions of ‘listed’ habitats of conservation concern. Ten of these biotopes could easily be considered Vulnerable Marine Ecosystems; three coral gardens, four cold-water coral reefs, two xenophyophore communities and one sponge dominated community, with remaining biotopes requiring more detailed assessment. Coral gardens were only found on positive geomorphic features, namely parasitic cones and radial ridges, found both sides of the seamount over a depth of 1311–1740 m. Two cold-water coral reefs (equivalent to summit reef) were mapped on the NW side of the seamount; Lophelia pertusa reef associated with the cliff top mounds at a depth of 747–791 m and Solenosmilia variabilis reef on a radial ridge at a depth of 1318-1351 m. Xenophyophore communities were mapped from both sides of the seamount at a depth of 1099–1770 m and were either associated with geomorphic features or were in close proximity (< 100 m) to them. The sponge dominated community was found on the steep escarpment either side of the seamount over at a depth of 854-1345 m. Multivariate diversity revealed the xenophyophore biotopes to be the least diverse, and a hard substratum biotope characterised by serpulids and the sessile holothurian, Psolus squamatus, as the most diverse.