Monitoring of Algal Diversity and Richness on the Glacial Moraine of Sarn Badrig
Sarn Badrig (St Patrick's Causeway) is a belt reef running in a south-westerly direction approximately 18 km out from Mochras Point near Harlech. This reef forms part of the Pen Llyn a'r Sarnau Special Area of Conservation (SAC) protected under the EC Habitats Directive. The reef is composed of glacial moraine deposits and is exposed in patches at low water along most of its length. The reef structure is very mobile and subject to tidal currents, wave action and sand scour and therefore many of the seaweeds found on the reef are annual or perennial species able to survive the scoured conditions. These include a number of rare species that would be overgrown by species that would normally establish on more stable reef environment. The purpose of this data capture was to map the distribution of substratum types and select biological indices. Also to assess and determine a suitable methodology to monitor algal richness within a benthic habitat of dynamic substrata. The site will only be assessed for its algae richness and diversity every 2 years.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS110947
- Alternative Title
-
- Monitro cyfoeth ac amrywiaeth algau ar farian rhewlifol Sarn Badrig.
- Sarn Badrig algae diversity and richness
- Metadata Language
- English
- Lineage
-
Algae diversity and richness monitoring at Sarn Badrig is conducted in 2 stages. Stage 1, habitat mapping and stage 2, algal richness. The site is marked with a permanent tripod structure and provides a reference point for mapping the surrounding substrata. An area 25 m x 25 m is marked out North East of the tripod marker and at 5 m intervals a quadrat is used to record the substratum (percentage cover of sand, gravel, pebbles and boulder) and biota features (percentage cover of algal turf, presence/absenceof H.siliquosa and Laminaria spp). Also recorded is how representative the area is of the habitat MIR.HalXK. This process is repeated North West, South West and South East of the marker to form a 50 m x 50 m area with the marker in the centre. A total of 100 quadrats are completed. The area that is most representative of the habitat MIR.HalXK is selected for monitoring algal richness. Its distance and bearing from the pyramid is recorded. Due to the difficulty of identifying algae species in-situ within a limited time period, different methods of measuring species richness were investigated in 2005. In 2007, 2 divers each used a 0.25 m quadrat to record algal species, in 10 min intervals up to one hour. The quadrat is used as a tool to focus the search and is moved around the sector by the divers. Detailed methodologies can be found in Marine Monitoring Report 25b (standard operating procedures 7 and 8 for the 2005 methods). Established as Life Monitoring Trials - CCW report 380, chapter 3.1.1 Contract Science Report 380, followed by contracted Across Wales diving project. Whilst most species were identified in situ, some were gathered for subsequent laboratory analysis using algal identification keys and microscope. Samples of algae were pressed, scanned on a flat-bed colour scanner and incorporated into the CCW herbarium.
- Dataset Reference Date (Publication)
- 2009-08-01
Temporal Extent
- Begin date
- 2005-06-09
- End date
- 2009-12-31
- Topic category
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- Biota
Extent
Extent
- Geographic Extent
- Irish Sea
- Geographic Extent
- Cardigan Bay
- Geographic Extent
- Tremadog Bay
- Geographic Extent
- GWYNEDD - GWYNEDD
))
Vertical Extent
- Medin Extent Keyword
- benthic boundary layer
Vertical Extent
- Minimum value (metres)
- 0
- Maximum value (metres)
- -7.6
- Vertical CRS
Distribution
- Format Type and Description
-
-
Documents
()
- Specification
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[A] Reports in word and pdf format. [B] Habitat data in excel spreadsheet format. [C] Species richness data available as excel spreadsheets. [D] Pressed seaweed specimens and scanned images held as .JPGs and .TIFs. [E] Incidental video as mini dvd tapes.
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Documents
()
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
-
Algae diversity and richness monitoring at Sarn Badrig is conducted in 2 stages. Stage 1, habitat mapping and stage 2, algal richness. The site is marked with a permanent tripod structure and provides a reference point for mapping the surrounding substrata. An area 25 m x 25 m is marked out North East of the tripod marker and at 5 m intervals a quadrat is used to record the substratum (percentage cover of sand, gravel, pebbles and boulder) and biota features (percentage cover of algal turf, presence/absenceof H.siliquosa and Laminaria spp). Also recorded is how representative the area is of the habitat MIR.HalXK. This process is repeated North West, South West and South East of the marker to form a 50 m x 50 m area with the marker in the centre. A total of 100 quadrats are completed. The area that is most representative of the habitat MIR.HalXK is selected for monitoring algal richness. Its distance and bearing from the pyramid is recorded. Due to the difficulty of identifying algae species in-situ within a limited time period, different methods of measuring species richness were investigated in 2005. In 2007, 2 divers each used a 0.25 m quadrat to record algal species, in 10 min intervals up to one hour. The quadrat is used as a tool to focus the search and is moved around the sector by the divers. Detailed methodologies can be found in Marine Monitoring Report 25b (standard operating procedures 7 and 8 for the 2005 methods). Established as Life Monitoring Trials - CCW report 380, chapter 3.1.1 Contract Science Report 380, followed by contracted Across Wales diving project. Whilst most species were identified in situ, some were gathered for subsequent laboratory analysis using algal identification keys and microscope. Samples of algae were pressed, scanned on a flat-bed colour scanner and incorporated into the CCW herbarium.
Keywords
Keywords
Keywords
- NRW Thesaurus
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- marine monitoring (see also marine surveys)
- Special Area of Conservation Monitoring
- Pen Llyn a'r Sarnau cSAC
- Sarn Badrig Reef
- algae
- richness
- diversity
- quadrats
- Type
- Theme
Citation
- Date (Publication)
- 2023-12-31
Keywords
- SeaDataNet Parameter Discovery Vocabulary
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- Macroalgae generic abundance in water bodies
- Type
- Theme
Citation
- Date (Revision)
- 2021-01-06
Spatial Reference System
Content
Content Information
NRW Profile
Custom Elements
- NRW Related Title
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The establishment of a programme of surveillance and monitoring for judging the condition of the features of Pen Llyn a'r Sarnau cSAC : 1. Progress to March 2001
Constraints
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
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© 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.
Metadata
Metadata
- File Identifier
- 4f4c4942-4343-5764-6473-313130393437 XML
- Metadata Language
- English
- Parent Identifier
-
Across Wales Diving Monitoring Project (2004)
NRW_DS109743
- Resource type
- Dataset
- Metadata Date
- 2024-12-09T12:31:55.743Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
-
1.0