The dataset includes time-series of Posidonia oceanica production over ~20 years (1997 -2018) at sixty sites in the Greek Seas. The dataset also include environmental variables for the same sites and time -period (i.e., sea surface temperature, sea surface temperature of August, Chlorophyll a, Suspended particulate matter, Secchi depth)

The dataset contains circalitoral habita types in the Slovenian coastal area. It contains the description of habitat types, EUNIS codes, areas of the habitat and the key species described.

Combined use of optical (satellite imagery), and acoustic (sidescan sonar) remote sensing techniques, as well as in situ methodologies (visual census; SCUBA diving, Towed Underwater Cameras, and Remotely Operated Vehicles) was employed to map the spatial distribution of seagrass habitats in the coastal waters of the Hellenic territory. Seagrass meadows were recorded at approximately 70% of the Hellenic coastline (Eastern Ionian, Aegean and Levantine Seas), and their surface area exceeded 2,673.1 km2. Posidonia oceanica is -by far- the dominant seagrass species of the Hellenic seas, covering the vast majority of seabed at depths between the shoreline and 25 – 30 m (or deeper in insular areas), followed by the species Cymodocea nodosa, Zostera noltei, and Halophila stipulacea, which, however, presenting local presence and limited areal extent. Habitat suitability in terms of the seabed spatial extent that is available for the growth of seagrass meadows (i.e., the spatial extent of coastal areas between the shoreline and the isobath of 20m) and the seawater clarity conditions are highlighted as the critical factors for the formation of well-structured and extensive meadows. The results of this study are of great importance and usefulness for the effective management and conservation of valuable marine ecosystems. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

List of macroinvertebrate taxa found in Sacharina latissima and Alaria esculenta cultivated on longlines. Objectives within WP6 of GENIALG: assessing the biodiversity associated with cultivated seaweed. Location of seaweed farm: Ventry Harbour, Ireland. Dataset consists of macroinvertebrate taxa identified and enumerated from 25 cm replicate seaweed samples removed from the longlines. The samples were collected at seven different time points along the growing season in 2018 and 2019. Samples collected as part of the GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry.

List of macroinvertebrate taxa associated with experimental dropper replicates. Droppers are 1m long polypropylene ropes attached to existing longlines in seaweed farm located in Ventry Harbour, Co. Kerry Ireland. Treatments: rope seeded with Sacharina latissima sporophytes and unseeded controls. Objectives within WP6 of GENIALG: assessing the biodiversity associated with cultivated seaweed. Dataset consists of macroinvertebrate taxa identified and enumerated by NUIG biologists supervised by project lead researcher Dr. Jose M. Farinas-Franco. The samples were collected in July 2018, three months after deployment. The aim was to characterise fauna associated with cultivated seaweed and ancillary structures. Samples collected as part of the GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry.

Part of Deliverable 6.1 of GENIALG Project. Datasets used for parametrisation of models and evaluation of seaweed farm environmental footprint. Sediment samples collected using van veen grabs and analysed for granulometry and organic matter content. Locations and dates indicated on dataset. Records obtained at Ventry Harbour test farm between September 2017 and April 2019 during GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry.

Part of Deliverable 6.1 of GENIALG Project. Datasets used for parametrisation and validation of models and evaluation of farm footprint. The dataset consists of continuous and spot sampling records of temperature, salinity (conductivity), turbidity, Secchi disk depths, irradiance (as PAR), nutrients and suspended matter content in water samples. Records obtain at Ventry Harbour test farm between September 2017 and October 2019 during GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry.

List of macroinvertebrate taxa associated with experimental dropper replicates. Collected at two test seaweed farms in The Netherlands. Samples collected as part of the GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry. A total of twelve seaweed lines (droppers of 2m length) were deployed in the farm at November 21st 2018. Six lines were located on the outer edge of the farm and six lines were located in the middle of the farm. At both locations three lines were seeded with seaweed and three lines were left empty. The ropes were collected on the 24th of April by gently removing the ropes from the water and directly transferring them into plastic bags. On May 14th 2020 droppers were randomly selected and cut from the longlines and processed following the same protocols.

Species abundance and seagrass cover. Calculated from photo quadrats and video recorded by divers along seabed transects surveyed by divers as part of GENIALG monitoring surveys. Seaweed farm located in Ventry Harbour, Co. Kerry (Ireland). The samples were collected at seven different time points along the growing season in 2018 and 2019. Samples collected as part of the GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry.

This record is for Approval for Access product AfA128. Information regarding the presence, and percentage cover, of seagrass species at specific marine monitoring points held within the Environment Agency’s BIOSYS database (our main database for storing, manipulating and reporting data from freshwater and marine biological surveys at any taxonomic level). These data represent ground-truthing monitoring for the ecological assessment of seagrasses within transitional and coastal waters of England and Wales. Seagrass data on BIOSYS are updated as new monitoring data are made available. Monitoring for seagrass occurs June to September with records being updated after the sampling season. The extracted data is a subset of the full dataset and only includes data collected/owned by the Environment Agency. Attribution statement: © Environment Agency copyright and/or database right 2015. All rights reserved.