Gwaith monitro acwstig yn Ne Llyn (i'r dwyrain o Ynys Tudwal) a gwaith dilynol ar samplo'r isfilod
A side-scan sonar survey was carried out in Tremadog Bay following reports of possible scallop dredging within the Sea Fisheries Scallop Exclusion Zone. The acoustic survey was followed up by infaunal sampling to look at the effect of disturbance of the substrata within the area. The purpose of this data capture was to investigate reports of possible scallop dredging within the Exclusion Zone and its effects on biodiversity within the Special Area of Conservation (SAC) and Exclusion Zone. Confidence in this dataset is high. The side-scan data is processed to reduce errors (e.g. positional corrections).
- Dull adnabod
- Rhychwant
- Dosbarthiad
- Ansawdd
- Allweddeiriau
- System Cyfeirio Gofodol
- Cynnwys
- Cyfyngiadau
- Cynnal a chadw
- Metadata
Dull adnabod
- Dynodydd
- NRW_DS110872
- Teitl Amgen
-
- Side-scan survey of South Llyn
- Laith Metadata
- English
- Datganiad
-
Side scan-sonar data was captured from Countryside Council for Wales' (CCW) research vessel (R.V. Pedryn) using a CMAX CM800 side-scan sonar. Two areas were selected for infaunal sampling. A control site (with no dredge activity) and one area where there was evidence of recent dredge activity. Infaunal sampling was carried by divers using a 0.1 m2 quadrat. 5 Quadrats were randomly placed in the belly of a dredge scar and 5 within the control site. Surface material was collected by hand and a diver operated suction sampler was used to remove the sediment within the quadrat to a depth of 20cms using a 0.5mm filter mesh bag. Large cobbles within the sediment too big for sampler were removed by hand and placed in a large 0.5mm mesh sample bag along with the plastic bag containing surface cobbles and the suction sampler filter bag. A sediment sample was collected by the diver adjacent to the quadrat using a 1/2litre sealed plastic bucket for granulometry. The contents of the suction sample filter bag and cobbles from within the sediment were transferred to sample buckets on the surface and fixed in 20% formalin diluted with seawater. In addition one 2x2 m quadrat was photographed in 40 cm blocks at both the control site and within one dredge scar. Photos will be stitched together to create a photographic mosaic of the quadrat.
- Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
- 2009-08-31
Ystod amser
- Dyddiad cychwyn
- 2009-06-09
- Dyddiad gorffen
- 2009-08-31
- Categori pwnc
-
- Environment
- Biota
Rhychwant
Rhychwant
- Hyd
- Irish Sea
- Hyd
- GWYNEDD - GWYNEDD
))
Maint Fertigol
- Maint allweddair MEDIN
-
benthic boundary layer
Maint Fertigol
- Gwerth lleiaf
- 0
- Gwerth uchaf
- -12
- System Gyfeirio Cydlynu Fertigol
Dosbarthiad
- Fformat - Math a Disgrifiad
-
-
Documents
(
)
- Math
-
[A] Side-scan data mosaiced raster TIFF images [B] Video data as avi files [C] Dredge position and sample metadata in MapInfo TAB files [D] Images as JPGs and NEF raw files
-
Documents
(
)
Ansawdd
Ansawdd Data
- Cwmpas Ansawdd
- Dataset
- Cydymffurfiad
- 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
- Eglurhad
-
This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
- Gradd
- false
- Datganiad
-
Side scan-sonar data was captured from Countryside Council for Wales' (CCW) research vessel (R.V. Pedryn) using a CMAX CM800 side-scan sonar. Two areas were selected for infaunal sampling. A control site (with no dredge activity) and one area where there was evidence of recent dredge activity. Infaunal sampling was carried by divers using a 0.1 m2 quadrat. 5 Quadrats were randomly placed in the belly of a dredge scar and 5 within the control site. Surface material was collected by hand and a diver operated suction sampler was used to remove the sediment within the quadrat to a depth of 20cms using a 0.5mm filter mesh bag. Large cobbles within the sediment too big for sampler were removed by hand and placed in a large 0.5mm mesh sample bag along with the plastic bag containing surface cobbles and the suction sampler filter bag. A sediment sample was collected by the diver adjacent to the quadrat using a 1/2litre sealed plastic bucket for granulometry. The contents of the suction sample filter bag and cobbles from within the sediment were transferred to sample buckets on the surface and fixed in 20% formalin diluted with seawater. In addition one 2x2 m quadrat was photographed in 40 cm blocks at both the control site and within one dredge scar. Photos will be stitched together to create a photographic mosaic of the quadrat.
Allweddeiriau
Allweddair
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2008-06-01
Allweddair
-
NRW Thesaurus
-
- acoustic remote sensing
- sediment epifauna
- sediment infauna
- sediment sample
- Infauna
- sidescan sonar
- acoustic observation (acoustic monitoring)
- benthic environment
- Tremadog Bay
- benthic communities
- surveillance
- marine sediments (coastal sediments) (intertidal sediments) (subtidal sediments)
- cockle dredging (hydraulic dredging)
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2026-08-27
Allweddair
System Cyfeirio Gofodol
Cynnwys
Gwybodaeth Cynnwys
Proffil CNC
Elfennau CNC
Cyfyngiadau
Cyfyngiadau
Cyfyngiadau ar Fynediad a Defnydd Cyhoeddus
- Math o Gyfyngiad
- Other restrictions
Cyfarwyddeb Cyfyngiadau Mynediad
- Cyfyngiadau
- no limitations
Testun cyfyngiadau mynediad
- Cyfyngiadau eraill
-
There are no access restrictions to this data. NRW may release, publish or disseminate it freely.
Defnyddiwch gyfyngiadau
- Cyfyngiadau Defnyddio
- Other restrictions
- Cyfyngiadau eraill
-
© CNC/NRW 2009 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. All intellectual property rights (including copyright and database rights) are owned by CCW, except video footage taken by Paul Kay. Applicants seeking to re-use this material should approach Paul Kay directly to obtain permission.
Metadata
Metadata
- Dynodydd Ffeil
- 4f4c4942-4343-5764-6473-313130383732 XML
- Laith Metadata
- English
- Math o adnodd
- Dataset
- Dyddiad Metadata
- 2026-09-28T14:06:52.698Z
- Enw Safonol Metadata
- NRW
- Fersiwn Metadata
-
1.0