Arolygon hydroacwstig ac arolygon o wyniaid Llyn Tegid a Llyn Arenig Fawr 2012
The gwyniad (Coregonus lavaretus) population of Llyn Tegid has, for a number of years, been considered threatened by deteriorating environmental conditions, particularly those associated with eutrophication.
This dataset contains the results of a project investigating the environmental factors affecting the species and its habitat. Attempts have been made since 2003 to establish a refuge population through the translocation of gwyniad to Llyn Arenig Fawr.
The purpose of this study was to assess the status of gwyniad and its habitat in both Llyn Tegid, which supports the native population, and Llyn Arenig Fawr, which supports the introduced population.
- Dull adnabod
- Rhychwant
- Dosbarthiad
- Ansawdd
- Allweddeiriau
- System Cyfeirio Gofodol
- Cynnwys
- Cyfyngiadau
- Cynnal a chadw
- Metadata
Dull adnabod
- Dynodydd
- NRW_DS115217
- Teitl Amgen
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- Gwyniad Hydroacoustic and Gill Netting Survey of Llyn Arenig Fawr 2012- CCW Science Report 1013 CCW000800000000I
- Gwyniad Hydroaccoustic Survey of Llyn Tegid 2012 - CCW Science Report 1012 CCW000800000000G
- Laith Metadata
- English
- Datganiad
-
At Llyn Tegid, hydroacoustic surveys were conducted alongside measurements of associated environmental variables, including temperature and oxygen profiles, and Secchi disc readings.
The survey utilised the standardised protocol for the assessment and monitoring of whitefish populations (Bean, 2003; JNCC, 2005), with two minor deviations. Firstly, the fish length-target strength relationship described by Love (1971) was used instead of that proposed by Foote (1987) to facilitate wider comparison with other studies. Secondly, a vessel speed of 2.0 m s⁻¹ was adopted as the target mean speed rather than as an absolute upper limit.
Equivalent data collection was also undertaken at Llyn Arenig Fawr, including a standardised gill-net survey.
This dataset forms part of the continuation of the Llyn Tegid Hydroacoustic Surveys and Gwyniad Translocations 2004-2009 project.
- Gwybodaeth ychwanegol
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Ffynnon Reference Number: DCT-13-068971 / DCT-13-068914: Llyn Tegid Hydroacoustic Survey 2012 I. Winfield., J. Fletcher., and J. James., CCW Contract Science Report No. 1012
Ffynnon Reference Number: DCT-13-068851 / DCT-13-069046: Llyn Arenig Fawr Gwyniad Survey 2012 Winfield., J. Fletcher., and J. James., CCW Contract Science Report No. 1013
- Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
- 2012-08-07
Ystod amser
- Dyddiad cychwyn
- 2012-08-06
- Dyddiad gorffen
- 2012-08-07
- Categori pwnc
-
- Biota
Rhychwant
Rhychwant
- Hyd
- GWYNEDD - GWYNEDD
))
Maint Fertigol
- Maint allweddair MEDIN
-
water column
Dosbarthiad
Dosbarthiad
- Fformat - Math a Disgrifiad
-
-
Binary
(
Unknown
)
- Math
-
Oxygen and temperature profiles in Excel (.xls) format; Raw echo sounder acquisition data (.dt4); Species data in Excel (.xls) format
-
Database
(
Unknown
)
- Math
-
Recorder 6 species datasets
-
Delimited
(
Unknown
)
- Math
-
Echoview laboratory analysis data in CSV format
-
Image
(
Unknown
)
- Math
-
JPEG images
-
Documents
(
Unknown
)
- Math
-
Final reports in Microsoft Word and Adobe PDF formats
-
Binary
(
Unknown
)
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
-
At Llyn Tegid, hydroacoustic surveys were conducted alongside measurements of associated environmental variables, including temperature and oxygen profiles, and Secchi disc readings.
The survey utilised the standardised protocol for the assessment and monitoring of whitefish populations (Bean, 2003; JNCC, 2005), with two minor deviations. Firstly, the fish length-target strength relationship described by Love (1971) was used instead of that proposed by Foote (1987) to facilitate wider comparison with other studies. Secondly, a vessel speed of 2.0 m s⁻¹ was adopted as the target mean speed rather than as an absolute upper limit.
Equivalent data collection was also undertaken at Llyn Arenig Fawr, including a standardised gill-net survey.
This dataset forms part of the continuation of the Llyn Tegid Hydroacoustic Surveys and Gwyniad Translocations 2004-2009 project.
Allweddeiriau
Allweddair
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2008-06-01
Allweddair
-
NRW Thesaurus
-
- gwyniad (freshwater whitefish)
- coregonus lavaretus
- hydroacoustic
- Llyn Tegid
- secchi depth
- Llyn Arenig Fawr
- oxygen profile
- marine and freshwater inventory
- temperature profile
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2026-08-27
Allweddair
System Cyfeirio Gofodol
Cynnwys
Gwybodaeth Cynnwys
Proffil CNC
Elfennau CNC
- Teitlau cysylltiedig CNC
-
Llyn Arenig Fawr Gwyniad survey 2009
- Teitlau cysylltiedig CNC
-
Llyn Tegid hydroacoustic survey 2012
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 2012. 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.
Datganiad Priodoli
- Cyfyngiadau eraill
-
Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
Math o Drwydded
- Cyfyngiadau eraill
- Open Government Licence
Metadata
Metadata
- Dynodydd Ffeil
- 4f4c4942-4343-5764-6473-313135323137 XML
- Laith Metadata
- English
- Dynodydd Rhiant
-
Freshwater Gwyniad (Coregonus lavaretus) Species Survey Data
NRW_DS116344
- Math o adnodd
- Dataset
- Dyddiad Metadata
- 2026-10-01T14:09:35.124Z
- Enw Safonol Metadata
- NRW
- Fersiwn Metadata
-
1.0