All Wales Phase 1 Terrestrial - Mosaic Layer Voronoi

Haen Mosaig Tir Cymru Gyfan

This dataset is a GIS browser table that contains information on the habitats present and their proportions and areas in mosaic polygons. This method of dealing with mosaics is based on the approach used for mosaics in Phase 2 vegetation survey GIS datasets.

The original field surveys were carried out as part of a national habitat survey programme required to implement conservation at a local level. An all-Wales 1km square dataset was created for the generation of national statistics on habitat coverage, and the maps were digitised as part of the project to map Open Access land. The dataset was subsequently imported into a GIS to enable its disaggregation into various different geographical regions within Wales. Voronoi was carried out to enable full representation and visualisation of the components of complex mixed-habitat upland polygons and the mosaic browser lists habitats in mosaic polygons and gives proportions and area data.

Habitat mixtures were treated as equal splits, e.g. D.1.1 and E.2.1 in the string 'D.1.1 + E.2.1' were allocated proportions 1 : 1, and mosaics were treated as subsidiary divisions, e.g. the components of the string 'D.1.1 + D.2/E.2.1' were allocated proportions 2 : 1 : 1. Habitats in brackets were allocated proportions of 2 percent. The Phase 2 Tools were used to create a mospolys (mosaic polygons) layer to which the Phase 1 legend can be applied for better visualisation in GIS.

Dynodydd Identifier: NRW_DS115876

Teitl Amgen Alternative Title

Phase 1 Mosnotes voronoi.lyr
Phase 1 Mospolys voronoi.lyr

Laith Metadata Metadata Language: English

Lineage: Voronoi procedure carried out on the cleaned version of the vegetation layer, and mosaic browser created from this.

Closely co-ordinated teams of surveyors carried out field recording of habitats onto 1:10,000 scale maps (rarely 1:25,000 during the upland stage). The minimum size of habitat patch recorded lies predominantly within the range 0.1-0.25 ha, although smaller areas were mapped in the lowlands. The survey methods employed during the initial upland stage are given in more detail in a WFU report (Day, A. (1989) Upland Vegetation Survey 1979-1989 Background Methodology and Summary of Data Collected. NCC, Bangor). Methods for the lowland survey followed the Handbook for Phase 1 Habitat Survey with some minor modifications adopted for use in Wales (Howe E.A. and Blackstock T.H. (1991) Supplementary Notes for Phase I Survey in Wales. CCW, Bangor).

The voronoi procedure was carried out in MapInfo to split complex upland mixed habitat polygons into component parts using a tool written in-house by the GIS and Spatial Data Team within NRW. A study of survey reliability was conducted during the lowland phase (Kerry, Rimes, Smith, Williams. 1994. An Assessment of Errors in Phase I Habitat Survey in Wales. Bangor: Countryside Council for Wales, Report No. 94/4/1). It showed the field mapping to be 83% repeatable (Stevens, Blackstock, Howe, Stevens. 2004. Repeatability of Phase 1 habitat survey. J. Environ. Manage. 73, 53-59).

The electronic data have undergone a series of checks for accuracy both by the contractor and subsequently within CCW. The extent of upland flush and upland species-rich ledges may be over-estimated by the voronoi procedure.

Dyddiad cyfeirnod y set ddata (Cyhoeddiad) Dataset Reference Date (Publication): 2014-11-20

Perchennog

Owner

Natural Resources Wales (NRW)

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

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

Cychwynnwr

Originator

Natural Resources Wales (NRW)

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

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

Extent

Hyd Geographic Extent: Wales (WLS)

Fformat - Math a Disgrifiad Format Type and Description

Geographic Information System ( )

Specification

[A] GIS layers in MapInfo tab. Format

Ansawdd Data

Data quality

Cwmpas Ansawdd Quality Scope: Dataset

Dataset

Cydymffurfiad 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: This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
Degree: false

Lineage: Voronoi procedure carried out on the cleaned version of the vegetation layer, and mosaic browser created from this.

Closely co-ordinated teams of surveyors carried out field recording of habitats onto 1:10,000 scale maps (rarely 1:25,000 during the upland stage). The minimum size of habitat patch recorded lies predominantly within the range 0.1-0.25 ha, although smaller areas were mapped in the lowlands. The survey methods employed during the initial upland stage are given in more detail in a WFU report (Day, A. (1989) Upland Vegetation Survey 1979-1989 Background Methodology and Summary of Data Collected. NCC, Bangor). Methods for the lowland survey followed the Handbook for Phase 1 Habitat Survey with some minor modifications adopted for use in Wales (Howe E.A. and Blackstock T.H. (1991) Supplementary Notes for Phase I Survey in Wales. CCW, Bangor).

The voronoi procedure was carried out in MapInfo to split complex upland mixed habitat polygons into component parts using a tool written in-house by the GIS and Spatial Data Team within NRW. A study of survey reliability was conducted during the lowland phase (Kerry, Rimes, Smith, Williams. 1994. An Assessment of Errors in Phase I Habitat Survey in Wales. Bangor: Countryside Council for Wales, Report No. 94/4/1). It showed the field mapping to be 83% repeatable (Stevens, Blackstock, Howe, Stevens. 2004. Repeatability of Phase 1 habitat survey. J. Environ. Manage. 73, 53-59).

The electronic data have undergone a series of checks for accuracy both by the contractor and subsequently within CCW. The extent of upland flush and upland species-rich ledges may be over-estimated by the voronoi procedure.

Allweddair

Keywords

GEMET - INSPIRE themes, version 1.0

Habitats and biotopes

Math Type: Theme

Theme

Dyfyniad

Citation

Dyddiad (Cyhoeddiad) Date (Publication): 2008-06-01

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

Allweddair

Keywords

NRW Thesaurus

Phase 1 Habitat Survey
future of the uplands
lowlands

Math Type: Theme

Theme

Dyfyniad

Citation

Dyddiad (Cyhoeddiad) Date (Publication): 2024-06-19

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

Code: British National Grid (EPSG::27700)

Gwybodaeth Cynnwys

Content Information

Proffil CNC

NRW Profile

Elfennau CNC

Custom Elements

NRW Related Title: Handbook for phase 1 habitat survey : a technique for environmental audit. Field Manual

NRW Related Title: Handbook for phase 1 habitat survey : a technique for environmental audit

NRW Related Title: Upland vegetation survey 1979-1989 : background, methodology and summary of data collected

NRW Related Title: An assessment of errors in Phase I habitat survey in Wales. Confidential

Constraints

Limitations on Public Access and Use

Math o Gyfyngiad Restriction type: Other restrictions

Other restrictions

Access Constraints Directive

Limitations: no limitations

Access Constraints Text

Other constraints: There are no access restrictions on this data. NRW may release, publish or disseminate it freely.

Use Constraints

Cyfyngiadau Defnyddio Use constraints type: Other restrictions

Other restrictions

Other constraints: © CNC/NRW All rights Reserved. Contains Ordnance Survey Data. Ordnance Survey Licence number AC0000849444. Crown Copyright and Database Right Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and copyright of the owners. It is the recipient's responsibility to ensure the data is fit for the intended purpose.

Attribution Statement

Other constraints: Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved. Contains Ordnance Survey Data. Ordnance Survey Licence number AC0000849444. Crown Copyright and Database Right.

Licence

Other constraints: Open Government Licence

Metadata

Dynodydd Ffeil File Identifier: 4f4c4942-4343-5764-6473-313135383736 XML

Laith Metadata Metadata Language: English

Parent Identifier: Terrestrial Phase 1 Habitat Survey
NRW_DS24715

Math o adnodd Resource type: Dataset

Dataset

Dyddiad Metadata Metadata Date: 2025-02-04T10:10:35.774Z

Enw Safonol Metadata Metadata Standard Name: NRW

Fersiwn Metadata Metadata Standard Version: 1.0

Pwynt Cyswllt

pointOfContact

Natural Resources Wales (NRW)

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

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

Publishing Body

Access the portal

Full access to the portal and metadata.

All Wales Phase 1 Terrestrial - Mosaic Layer Voronoi

Haen Mosaig Tir Cymru Gyfan

Identification

Extent

Extent

Distribution

Quality

Ansawdd Data

Data quality

Keywords

Allweddair

Keywords

Dyfyniad

Citation

Allweddair

Keywords

Dyfyniad

Citation

Spatial Reference System

Content

Gwybodaeth Cynnwys

Content Information

Proffil CNC

NRW Profile

Elfennau CNC

Custom Elements

Constraints

Constraints

Limitations on Public Access and Use

Access Constraints Directive

Access Constraints Text

Use Constraints

Attribution Statement

Licence

Metadata

Metadata

Publishing Body

Identification

Extent

Extent

Distribution

Quality

Ansawdd Data Data quality

Keywords

Allweddair Keywords

Dyfyniad Citation

Allweddair Keywords

Dyfyniad Citation

Spatial Reference System

Content

Gwybodaeth Cynnwys Content Information

Proffil CNC NRW Profile

Elfennau CNC Custom Elements

Constraints

Constraints

Limitations on Public Access and Use

Access Constraints Directive

Access Constraints Text

Use Constraints

Attribution Statement

Licence

Metadata

Metadata

Publishing Body

Ansawdd Data

Data quality

Allweddair

Keywords

Dyfyniad

Citation

Allweddair

Keywords

Dyfyniad

Citation

Gwybodaeth Cynnwys

Content Information

Proffil CNC

NRW Profile

Elfennau CNC

Custom Elements