Survey of Lakes in the Migneint-Arenig-Dduallt Proposed Site of Special Scientific Interest (pSSSI) Special Area of Conservation (SAC) and Special Protection Area (SPA)

The Migneint-Arenig-Dduallt Proposed Site of Special Scientific Interest (pSSSI) and Special Area of Conservation (SAC) is situated in North Wales in the Snowdonia National Park. The pSSSI/SAC boundary marks the limit of a large upland block located along the eastern fringe of the National Park. The primary reasons for the site qualifying for SAC status are the large areas of blanket bog, a priority habitat under the Habitats Directive, and the upland European dry heath. Other qualifying features include two Annex I habitat lake types: (1) oligotrophic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoeto-Nanojuncetea, and (2), natural dystrophic lakes and ponds. The limnological surveys (surveys of inland water) focus on the collation of site and catchment data and the collection of new data on lake bathymetry, water quality and macrophyte assemblages. A particular focus is an assessment of the current acidification and conservation status of the four lake sites. A preliminary assessment of whether the lakes are in favourable condition, as defined in the Habitats Directive, is also outlined. The primary aim of this project was to survey four lakes in the Migneint-Arenig-Dduallt pSSSI/SAC in order to build up CCWs datasets on Welsh lakes. The information collected is required for conservation site assessments, ecological quality judgements for site condition reporting, contributions to site management plans and assistance with casework issues.

Identifier: NRW_DS109993

Alternative Title

Arolwg o lynnoedd yn SoDdGAa/ACA/AGA Migneint-Arenig-Dduallt

Metadata Language: English

Lineage: Bathymetric Surveys- undertaken at Llynnau Tryweryn, Hesgyn and Hiraethlyn in August 2002. Echo sounding transects were run in a small boat between identifiable points on the shore and marked onto field maps, the transect end point locations were also recorded using a Geographical Positioning System (GPS). This produced a cross sectional profile of the lakebed on a paper chart for each transect. Lake areas, volumes and perimeter lengths calculated using planimetry. Standard physical and morphometric parameters were calculated from the survey data. No further field investigation were required at Llyn Conwy which had sufficient morphometric information from a 1986 survey. Physico-chemical survey-Water samples collected and temperature measured at the lake outflow. Temperature and dissolved oxygen profiles taken at the deepest part of each lake. Samples for soluble reactive phosphorus (SRP), total phosphorus (TP) and total nitrogen (TN) and filter papers for chlorophyll a were analysed. Acid neutralising capacity (ANC) estimated. Aquatic macrophyte survey- zonation and maximum growing depth examined using transects, all submerged floating leaved and emergent plants recorded. Plant distribution and abundance assessed and lake type determined.

Dataset Reference Date (Publication): 2003-09-30

Temporal Extent

Begin date: 2002-01-31

End date: 2003-12-31

Topic category

Inland waters
Environment

Owner

Natural Resources Wales (NRW)

Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales

http://naturalresources.wales/?lang=en

Originator

Centre for Ecology and Hydrology (CEH)

Environment Centre Wales, Deiniol Road, Bangor, Gwynedd, LL57 2UW, Wales

http://www.ceh.ac.uk/

Extent

Geographic Extent: Wales (WLS)

Format Type and Description

Documents Documents ()

Specification

[A] Report (MS Word, pdf-format) [B] Data in spreadsheet format (MS Excel)

Data quality

Quality Scope: Dataset

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: Bathymetric Surveys- undertaken at Llynnau Tryweryn, Hesgyn and Hiraethlyn in August 2002. Echo sounding transects were run in a small boat between identifiable points on the shore and marked onto field maps, the transect end point locations were also recorded using a Geographical Positioning System (GPS). This produced a cross sectional profile of the lakebed on a paper chart for each transect. Lake areas, volumes and perimeter lengths calculated using planimetry. Standard physical and morphometric parameters were calculated from the survey data. No further field investigation were required at Llyn Conwy which had sufficient morphometric information from a 1986 survey. Physico-chemical survey-Water samples collected and temperature measured at the lake outflow. Temperature and dissolved oxygen profiles taken at the deepest part of each lake. Samples for soluble reactive phosphorus (SRP), total phosphorus (TP) and total nitrogen (TN) and filter papers for chlorophyll a were analysed. Acid neutralising capacity (ANC) estimated. Aquatic macrophyte survey- zonation and maximum growing depth examined using transects, all submerged floating leaved and emergent plants recorded. Plant distribution and abundance assessed and lake type determined.

Keywords

GEMET - INSPIRE themes, version 1.0

Habitats and biotopes

Type: Theme

Citation

Date (Publication): 2008-06-01

Code: geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Keywords

NRW Thesaurus

Llyn Tryweryn
Llyn Hesgyn
Llyn Hiraethlyn
Llyn Conwy
Lakes (Limnology)
site management
aquatic macrophytes
Habitats Directive (Directive 92/43/EEC) (EC Habitats Directive) (European Community Habitats Directive)
Migneint-Arenig-Dduallt SAC
Conservation site assessments
Ecological quality
Bathymetric survey
Physico-chemical survey
Favourable condition
marine and freshwater inventory

Type: Theme

Citation

Date (Publication): 2023-12-31

Code: geonetwork.thesaurus.local.theme.converted_nrw-keywords

Code: British National Grid (EPSG::27700)

Content Information

NRW Profile

Custom Elements

NRW Related Title: Strategic CCW conservation lake survey : a survey of lakes in the Migmeint - Arenig - Dduallt pSSSI/SAC/SPA, Wales 2002 - 03 : final report

Constraints

Limitations on Public Access and Use

Restriction type: 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

Use constraints type: Other restrictions

Other constraints: © CNC/NRW 2003 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

File Identifier: 4f4c4942-4343-5764-6473-313039393933 XML

Metadata Language: English

Parent Identifier: Welsh Lakes Survey and Monitoring
NRW_DS123035

Resource type: Dataset

Metadata Date: 2024-05-31T09:22:25.956Z

Metadata Standard Name: NRW

Metadata Standard Version: 1.0

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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Full access to the portal and metadata.

Survey of Lakes in the Migneint-Arenig-Dduallt Proposed Site of Special Scientific Interest (pSSSI) Special Area of Conservation (SAC) and Special Protection Area (SPA)

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Temporal Extent

Extent

Extent

Distribution

Quality

Data quality

Keywords

Keywords

Citation

Keywords

Citation

Spatial Reference System

Content

Content Information

NRW Profile

Custom Elements

Constraints

Constraints

Limitations on Public Access and Use

Access Constraints Directive

Access Constraints Text

Use Constraints

Metadata

Metadata

Publishing Body