Review of Side-Scan Sonar Results from North Llyn Modiolus Reef

  • English
  • wel
  • All

An emergency review of side-scan sonar data collected by Countryside Council for Wales (CCW) in 2007 was required as the images showed marks that were potentially derived from trawling gear. The area was approximately 10 km by 6 km and approximately 1.5 km offshore, within the Pen Llyn a'r sarnau Special Area of Conservation (SAC) and is also protected under Sea Fisheries byelaws that prevent the use of trawls and dredges for the harvesting of molluscan shellfish, except as authorised by the local sea fisheries committee.

Identification

Dynodydd
Identifier
NRW_DS109893
Teitl Amgen
Alternative Title
  • Adolygiad o ganlyniadau gwaith monitro sonar yng Ngogledd Llyn
Laith Metadata
Metadata Language
English
Lineage

Side-scan images were collected by CCW as part of their annual monitoring of the reef. In addition to sides-scan sonar images, 3 dives were conducted in the area. Digital high definition video footage from the dives was edited and slowed so they could be examined for evidence of disturbance. Maps of sediment types and waved and tidally induced bed-sheer stress for the locality were provided by the HABMAP project. This project is based on annual side-scan sonar data collected by CCW as part of ongoing monitoring on the site. Data for 2007 identified anthropogenic activities on the site that required further study.
Additional Information

For further information about the methodology used for acoustic monitoring, please refer to metadata entry \Acoustic Monitoring of the North Llyn Modiolus reef\". "
Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
Dataset Reference Date (Publication)
2007-09-30
Perchennog
Owner
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Cychwynnwr
Originator
  Robinson
Earth, Ocean and Ecological Sciences, University of Liverpool, Nicholson Building, Liverpool, L69 3GP
http://www.liv.ac.uk/ecology
 

Extent

Extent

Hyd
Geographic Extent
GWYNEDD - GWYNEDD
N
W
E
S
Map representing the geographic extent of the dataset


 

Vertical Extent

Medin Extent Keyword
benthic boundary layer

Maint Fertigol
Vertical Extent

Gwerth lleiaf
Minimum value (metres)
-25
Gwerth uchaf
Maximum value (metres)
-45
System Gyfeirio Cydlynu Fertigol
Vertical CRS
 
 

Distribution

Fformat - Math a Disgrifiad
Format Type and Description
  • Image ()

    Specification

    [A] All raster images held as tif files. [B] Video footage held on mini DV tapes.

 

Quality

Ansawdd Data
Data quality

Cwmpas Ansawdd
Quality Scope
Dataset
Dataset
Cydymffurfiad
Conformity
Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services
Explanation
Degree
false
Lineage

Side-scan images were collected by CCW as part of their annual monitoring of the reef. In addition to sides-scan sonar images, 3 dives were conducted in the area. Digital high definition video footage from the dives was edited and slowed so they could be examined for evidence of disturbance. Maps of sediment types and waved and tidally induced bed-sheer stress for the locality were provided by the HABMAP project. This project is based on annual side-scan sonar data collected by CCW as part of ongoing monitoring on the site. Data for 2007 identified anthropogenic activities on the site that required further study.
 

Keywords

Allweddair
Keywords

GEMET - INSPIRE themes, version 1.0
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2008-06-01
Code
geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Allweddair
Keywords

NRW Thesaurus
  • sidescan sonar
  • acoustic observation (acoustic monitoring)
  • modiolus modiolus
  • horse mussel
  • Special Area of Conservation Monitoring
  • biogenic reef
  • Pen Llyn a'r Sarnau cSAC
  • dredging
  • disturbance
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2023-12-31
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords

Allweddair
Keywords

SeaDataNet Parameter Discovery Vocabulary
  • Side-scan sonar
  • Habitat extent
  • Habitat characterisation
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Adolygu)
Date (Revision)
2021-01-06
Code
geonetwork.thesaurus.external.theme.rdf+xml
 

Spatial Reference System

Code
Latitude and Longitude (EPSG::4326)
 

Content

Gwybodaeth Cynnwys
Content Information

Proffil CNC
NRW Profile

Elfennau CNC
Custom Elements

NRW Related Title

Review of sidescan sonar results from North Llyn
 

Constraints

Constraints

Limitations on Public Access and Use

Math o Gyfyngiad
Restriction type
Other restrictions
Other restrictions
 

Access Constraints Directive

Limitations
no limitations
 

Access Constraints Text

Other constraints

There are no access restrictions to this data. NRW may release, publish or disseminate it freely.
 

Use Constraints

Cyfyngiadau Defnyddio
Use constraints type
Other restrictions
Other restrictions
Other constraints

© CNC/NRW 2007 There are no use restrictions on this data. Recipients may re-use, reproduce, disseminate this data free of charge in any format or medium, provided they do so accurately, acknowledging both the source and NRW's copyright, and do not use it in a misleading context. It is the recipient's responsibility to ensure the data is fit for the intended purpose, that dissemination or publishing does not result in duplication, and that it is fairly interpreted. Advice on interpretation should be sought where required. To avoid re-using old data, users should periodically obtain the latest version from the original source.
 
 
 

Metadata

Metadata

Dynodydd Ffeil
File Identifier
4f4c4942-4343-5764-6473-313039383933 XML
Laith Metadata
Metadata Language
English
Parent Identifier
Acoustic Monitoring of the Extent of the North Llyn Modiolus Reef

NRW_DS109891
Math o adnodd
Resource type
Dataset
Dataset
Dyddiad Metadata
Metadata Date
2024-12-09T12:39:25.158Z
Enw Safonol Metadata
Metadata Standard Name
NRW
Fersiwn Metadata
Metadata Standard Version

1.0

Pwynt Cyswllt
pointOfContact
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 
 

Publishing Body

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