Mynydd Du Vegetation Map 2019
The extent of land cover classes on the common lands of Mynydd Du in the western end of the Brecon Beacons National Park derived from satellite imagery. The classes include dominant vegetation type, rock outcrop and scree, road and lake. The land cover classes follow the scheme used by the Meithrin Mynydd 1997 survey but with adjustments where some classes could not be separated. The dataset was derived from Sentinel 2 satellite imagery from 2019 with a pixel size of 10m by 10m on the ground. The goal was to extend vegetation mapping of the west end of Mynydd Du from 2018 carried out by NRW's Environmental Assessment Officer and so provide up-to-date vegetation mapping of upland grassland, moor and mire in an area actively managed by commoners for sheep grazing in collaboration with the BBNPA.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS125193
- Alternative Title
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- Map Llystyfiant Mynydd Du 2019
- Mynydd Du Vegetation Map 2019.hdr
- Mynydd Du Vegetation Map 2019.dat
- Metadata Language
- English
- Lineage
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Sentinel 2 imagery from 2019 for winter growth (24 February 2019) and summer growth (29 June 2019) were clipped to the Mynydd Du common land boundary, for Principal Component Analysis. The first 6 principal components were retained for classification. Pixels covered by OS MasterMap roads, lakes and mapped areas of Limestone grassland from 1997 were masked out to exclude them from the analysis. The remainder was classified by Maximum Likelihood Classification using training areas identified manually by expert knowledge instead of field work due to the time of year, COVID-19 restrictions and challenges converting the 2018 mapping into suitable training areas. Based on: a) Sentinel 2 Analysis Ready Data (ARD) processed by JNCC for DEFRA and taken from the CEDAR archive under an Open Government licence. b) OS MasterMap roads and lakes on the Mynydd Du Commons. c) The Mynydd Du Common land boundary. d) Limestone grassland areas from the Meithrin Mynydd Survey report of 1997. Sentinel imagery passed overhead around 11:30 and when combined with the east-west alignment of the ridges of Mynydd Du along with all the steep slopes facing north meant that winter imagery had north facing shadows that had an impact on classification. Accuracy not fully assessed.
- Dataset Reference Date (Publication)
- 2021-08-17
Extent
Extent
- Geographic Extent
- Wales (WLS)
))
Vertical Extent
Vertical Extent
- Minimum value (metres)
- 32
- Maximum value (metres)
- 802
- Vertical CRS
Distribution
- Format Type and Description
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Geographic Information System
()
- Specification
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ENVI format classified image
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Geographic Information System
()
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
-
Sentinel 2 imagery from 2019 for winter growth (24 February 2019) and summer growth (29 June 2019) were clipped to the Mynydd Du common land boundary, for Principal Component Analysis. The first 6 principal components were retained for classification. Pixels covered by OS MasterMap roads, lakes and mapped areas of Limestone grassland from 1997 were masked out to exclude them from the analysis. The remainder was classified by Maximum Likelihood Classification using training areas identified manually by expert knowledge instead of field work due to the time of year, COVID-19 restrictions and challenges converting the 2018 mapping into suitable training areas. Based on: a) Sentinel 2 Analysis Ready Data (ARD) processed by JNCC for DEFRA and taken from the CEDAR archive under an Open Government licence. b) OS MasterMap roads and lakes on the Mynydd Du Commons. c) The Mynydd Du Common land boundary. d) Limestone grassland areas from the Meithrin Mynydd Survey report of 1997. Sentinel imagery passed overhead around 11:30 and when combined with the east-west alignment of the ridges of Mynydd Du along with all the steep slopes facing north meant that winter imagery had north facing shadows that had an impact on classification. Accuracy not fully assessed.
Keywords
Keywords
- Type
- Theme
Citation
- Date (Publication)
- 2008-06-01
Keywords
- NRW Thesaurus
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- upland habitats
- Mynydd Ddu
- satellite images
- Type
- Theme
Citation
- Date (Publication)
- 2023-12-31
Keywords
- SeaDataNet Parameter Discovery Vocabulary
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- Habitat extent
- Type
- Theme
Citation
- Date (Revision)
- 2021-01-06
Spatial Reference System
Content
Content Information
NRW Profile
Custom Elements
Constraints
Constraints
Limitations on Public Access and Use
- Restriction type
- Other restrictions
Access Constraints Directive
- Limitations
- no limitations
Access Constraints Text
- Other constraints
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This data is comprised of a mixture of third party owned records and NRW records. The data is also considered OS derived data and is therefore jointly owned by NRW and the Ordnance Survey. There are no access restrictions on this data. However there are third party use restrictions.
Use Constraints
- Use constraints type
- Other restrictions
- Other constraints
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© CNC/NRW, © Ordnance Survey and © JNCC. Data may be re-used under provision and in line with the terms of a NRW licence. Those seeking commercial re-use require a commercial licence available from the OS.
Attribution Statement
- Other constraints
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NRW Conditional
Metadata
Metadata
- File Identifier
- 4f4c4942-4343-5764-6473-313235313933 XML
- Metadata Language
- English
- Resource type
- Dataset
- Metadata Date
- 2024-05-31T09:26:50.35Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
-
1.0