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  • An important task undertaken this year was to define sub-regional areas of the ICES greater North Sea eco-region. The sub-regional areas correspond to meaningful eco-logical units whose boundaries are defined by strong gradients in their physical oceanography, such as changes in depth, sediment transport, salinity, oxygen and currents. The four sub-regions of the ICES greater North Sea eco-region are; i. North-ern North Sea, ii. Southern North Sea, iii. Skagerrak and Kattegat, and iv. English Channel

  • Details the merged substrate maps produced within the proposed Skerries and Causeway Proposed Marine SAC.

  • This subtidal map was made in the framework of the Cartham project from 2009-2012. It incorporates remote sensing data in the form of a few side scan sonar profiles, along with a reasonable amount of sediment and fauna samples. Large gaps within the acoustic coverage were filled by the interpreter using evidence from bathymetric data, before the resulting polygons were labelled according to the biology contained in them. The habitat classification was a synthesis of the main habitat classifications, namely:Generic habitats from the Habitat Directive (EUR 27), elementary habitats from the French Cahiers d’habitats, the Rebent classification and EUNIS level 4 as much as possible.

  • This map covers both the intertidal zone and subtidal zones of the study sites. It is made from high resolution remote sensing data - both acoustic and optical - from various surveys carried out over the period 2008 to 2013 of various types: (i) multibeam echosounder (MBES), side scan sonar (SSS), RoxAnn acoustic ground discrimination system (AGDS), (ii) ortho-photography (the “Ortholittorale survey” from 2000), (iii) topographic and bathymetric lidar . It was complemented by (i) underwater video,(ii) sediment and biological grab samples, (iii) ground truth data from surveys in the tidal and infralittoral zone using GPS, annotations and photography.The habitat classification was a synthesis of the main habitat classifications, namely:Generic habitats from the Habitat Directive (EUR 27), Elementary habitats from the French Cahiers d’habitats, The Rebent classificationand EUNIS level 4 as much as possible. Map scale is in the range of 1:20000, with local improvements to 1:10000.

  • A geostatistical analysis of the data is reported leading to the selection of a linear model of corregionalization for the composition of the sediment, based on the additive log-ratio transformation of data on mud, sand and gravel content. This model is then used for spatial prediction on a 250-m grid. At each grid node a prediction distribution is obtained, conditional on neighbouring data and the selected model. By sampling from this distribution, and backtransforming onto the original compositional simplex of the data, we obtain a conditional expectation for the proportions of sand, gravel and mud at each location, a 95% confidence interval for the value at each node, and the probability that each of the four sediment texture classes that underlie the EUNIS habitat classification is found at the node.

  • Annex I habitat map created from data collected on the CEND 11/08 survey to Solan Bank - subsequently translated to EUNIS. Sublittoral sediments defined using acoustic and groundtruth data. Survey Techniques: Kongsberg EM3000D multi beam echosounder; Benthos SIS 1624 towed sidescan sonar; 0.1m2 Hamon grab; Rock dredge; Camera sledge; Drop frame video camera. See JNCC report 430, 2010 for more information. Orthorectified aerial photography used was flown to a scale of 1:5000. Photography was flown at low tide on a spring tide between the months of April and September to ensure maximum vegetation coverage. As a result of this and due to adverse weather conditions over some of the key tidal windows the whole project area was not captured in one block, but flown in stages between 2006 and 2009. Although ground-truthing was undertaken to support and validate the habitat map, not all areas were ground-truthed.

  • Mapis based on the interpretation of various types of data from a number of surveys carried out between 2011-2012 both in the intertidal and subtidal zones. Additionally the seabed « Carte G » from the French hydrographic survey (SHOM) was used in the interpretation process. In the tidal zone the identification was made by interpreting coastal ortho-photographs from BD Ortho (2005 et 2009) and digitising them on scale 1 : 2000ème with further qualification of the polygons based on ground truth data. For the subtidal zone, several data sources from 2011 were available: bathymetric lidar (with sounding density about 1pt*3m-2), side scan sonar (resolution of about 0.2m), underwater video, sediment and fauna samples collected with grabs and trawls. Addtionnally a single beam sounder was running at all times during the transects, which contributing to improve the depth DTM. In the outer rocky circalittoral zone, side scan sonar corridors were surveyed with a coverage of 30-50% depending on places. In the offshore deep circalittoral zone (known as La Grande vasière) where soft sediment is predominant, side scan sonar coverage was reduced to about 5-10%. In these latter two circalittoral zones, interpolation between sonar corridors was supported by SHOM « Carte G » (approx. scale 1:100000) along with a 100m resolution depth DTM. On rocky seabed, exposure at the seabed was described using kinetic energy from a combination of wave and current hydrodynamic models according to the methods described in: http://doi.org/10.13155/49975. Rocky substrate in intertidal and infralittoral zones was derived from the combined interpretation of both the topographic and bathymetric Lidar DTMs and aerial photographs, where permitted by water transparency. Various representations of the DTMs (slope, hillshade) helped delineate rocky outcrops with good reliability. Biological qualification of the substrate polygons was made through taxonomic analysis of benthos samples collected by MNHN in the framework of the project"Ecological assessment of Natura 2000 site - Roches de Penmarc’h".The final habitat classification was a synthesis of the main habitat classifications, namely: Generic habitats from the Habitat Directive (EUR 27), Elementary habitats from the French Cahiers d’habitats, The Rebent classificationand EUNIS level 4 as much as possible.

  • This map mostly results from the interpolation in gaps between surrounding maps. In places the rugosity derived from bathymetric data (soundings from hydrographic minutes and hydrographic lidar) enabled the interpreter to infer rocky seabed presence. In shallowest places aerial photography was also used to retrieve rocky seabed, distinguished from similar-looking Zostera beds owing to a historic Zostera bed inventory available to the project. The habitat classification was a synthesis of the main habitat classifications, namely: Generic habitats from the Habitat Directive (EUR 27), Elementary habitats from the French Cahiers d’habitats, The Rebent classificationand EUNIS level 4 as much as possible.

  • Targetted fishing ground for Nephrops norvegicus determined from Vessel Monitoring System data. The original classes assigned to the data were translated to the EUNIS habitat classification system as part of the MESH Atlantic project.

  • Marine Scotland Science surveyed 260 km2 of coastline west of the Isle of Lewis using swath bathymetry and drop frame TV camera and video. The bathymetry, backscatter data and ground truthing were used to interpret habitat maps of the seabed.