Irish Semi-natural Grassland Survey 2007-2012

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In 2008, following a 2007 pilot study in Roscommon and Offaly, a nationwide research study into the semi-natural grasslands of Ireland commenced. This study involved collecting botanical and environmental data from semi-natural grassland across all 26 counties. A total of 1192 sites were surveyed and 4633 releves (including 89 non-grassland releves) recorded. The semi-natural grassland habitats (GS and GM categories in Fossitt (2000)) within each site were digitally mapped in ArcMap. In addition, five EU Annex I grassland habitats (6210, 6230, 6410, 6430 and 6510) encountered during the project were surveyed, mapped, and their condition assessed. A small number of sites with 6130 were also surveyed but not assessed. Fuzzy analysis was used to analyse the vegetation data and a classification that contained 19 vegetation types has been proposed and documented. Site and releve data have been stored in an Access database and Turboveg, and two ArcMap shapefiles hold site polygon and releve point habitat data.

Coverage by County and year: 2008: Cork and Waterford 2009: Cavan, Monaghan, Leitrim and Longford 2010: Donegal, Dublin, Kildare and Sligo 2011 and 2012: Clare, Galway, Kerry, Limerick, Mayo, Tipperary, Carlow, Kilkenny, Laois, Louth, Meath, Westmeath, Wexford and Wicklow

Data Resources (4)

available as zip
available as PDF
available as html
available as html

Data Resource Preview - Zip file containing shapefiles download

Theme Environment
Date dataset released 2013-06-01
Date dataset updated 2016-10-19
Dataset conforms to these standards The INSPIRE Directive or INSPIRE lays down a general framework for a Spatial Data Infrastructure (SDI) for the purposes of European Community environmental policies and policies or activities which may have an impact on the environment.
Rights notes {,"Creative Commons Attribution 4.0 International License.",license,"Creative Commons Attribution 4.0 International License.",license}
Update frequency Never
Language English
Geographic coverage in GeoJSON format {"type":"Polygon","coordinates":[[[-11.2659477885, 51.2059662415],[-11.2659477885, 55.820224054], [-5.75081106972, 55.820224054], [-5.75081106972, 51.2059662415], [-11.2659477885, 51.2059662415]]]}
Spatial Reference Systems (SRS) TM75 / Irish Grid (EPSG:29903)
Vertical Extent {"maxVerticalExtent": "1014", "verticalDomainName": "EPSG Projection 5731 - Malin Head height", "minVerticalExtent": "0"}
Provenance information Habitat maps of the sites were drawn in the field using the colour aerial photograph in the site pack as a base map. A handheld GPS (Garmin GPS 76 with MapSource) was used in the field to accurately map site boundaries, areas of Annex I grassland habitats (Anon. 2007), non-Annex semi-natural grasslands (Fossitt 2000) and semi-improved grassland habitats, particularly where these were not visible on the photograph. The minimum mapping unit for habitats was 400 m2, with a minimum habitat width of 4 m. A habitat map of each site was produced using these data within ArcMap 9.3 Six ArcMap shapefiles were consolidated to create one shapefile containing mapped polygons of all sites surveyed in all years, 2007-2011. This involved several changes to the ISGS shapefile from the pilot study in 2007 in order to bring it in line with the mapping practices applied in subsequent years. Once the changes were applied, all individual shapefiles were standardised to contain identical columns, with data following set labelling conventions. Consolidation of the shapefiles occurred after standardisation. The following data-checking procedures were performed on the consolidated shapefile using ArcMap toolbox and ET GeoWizards: • All polygons and gaps below the minimum mapping size were examined • Slivers and overlapping polygons were identified and investigated • Any attribute lines with no corresponding polygon were eliminated • Relevés lying outside of polygons were examined and addressed • Conformity of all labels to labelling conventions was assured • Label mismatches between relevés and polygons were investigated and addressed, as were label mismatches within polygons • Multi-part features were examined and rendered single-part • A final general geometry check was run. Where anomalies with regard to irregular mapping or mismatching of habitats between relevés and polygons occurred, the original field data were consulted and the appropriate changes made to the GIS shapefile and/or consolidated Access and Turboveg databases. A separate shapefile created for grassland habitats surveyed and mapped in 2012 was appended to this consolidated shapefile after the 2012 field season, and the checks as outlined above were performed again. Data cross-checking Data checks among the three datasets Shapefile, Access database and Turboveg database were carried out to ensure the integrity of the data within and between them. Any differences were investigated, the original files or field data were consulted and the appropriate changes made to the datasets. Shapefile attribute fields: SITE_ID: ISGS site number ISGS_HAB: Habitat category according to Fossitt (2000) except that GSiX is used to denote semi-improved grassland habitat. FOSS_HAB: Habitat category according to Fossitt (2000). GA1 is used for semi-improved grassland habitat. ANNEX_I: Code of Annex I grassland habitat given if applicable. If non-Annex, this field has a value of "None". MAP_HAB: Grassland habitat that is displayed on habitat map in final pdf layouts. For non-Annex grassland habitats, the value in this field is equivalent to FOSS_HAB (therefore all semi-improved grassland is displayed as GA1). For Annex I grassland habitats, the value is equivalent to ANNEX_I. SURVEYED: Indicates whether the polygon has been walked through and had plant species recorded from it ("Yes") or not ("No"). COUNTY: County in which the polygon is located. SOURCE: Source of data from which polygon is mapped. Most cases are "ISGS" followed by the year in which it was surveyed. Three polygons were sourced from the grassland monitoring survey data of Dwyer et al. (2007). AREA_M2: Area of the polygon in square metres. X_COORD: X-coordinate of polygon centroid. Y_COORD: Y-coordinate of polygon centroid. COMMENT: Notes on the polygon. RELEVÉS A minimum of one 2 m x 2 m relevé was recorded from within each semi-natural grassland habitat mapped in each site, and in semi-improved grassland habitats deemed to have some conservation merit. Multiple relevés were recorded where there was significant variation in the sward composition within a habitat type, or where Annex I grassland habitat assessments were conducted. For each relevé, a 12-figure grid reference was obtained using a GPS unit. The following data-checking procedures were performed: • Relevés lying outside of polygons were examined and addressed • Label mismatches between relevés and polygons were investigated and addressed • Where anomalies with regard to irregular mapping or mismatching of habitats between relevés and polygons occurred, the original field data were consulted and the appropriate changes made to the GIS shapefile and/or consolidated Access and Turboveg databases. Shapefile attributes: RELEVE: ISGS releve number (<ISGS site number>_<releve number within site>). HAB_TYPE: Fossitt (2000) habitat in which the releve was recorded, except that semi-improved grassland is denoted GSiX rather than GA1. ANNEX_I: Annex I habitat (if any) in which the releve was recorded. If non-Annex habitat, value of field is "None". STOP: Monitoring stop number, if applicable. If the releve is not a monitoring stop, value of field is "0". VEG_TYPE: Vegetation type to which releve was assigned, according to proposed vegetation classification presented in O'Neill et al. 2013 ISGS report. A small number of plots with high-cover genus-level records were not assigned to a vegetation type. Non-grassland releves were also not assigned to a vegetation type. CORE_REL: Value is Y if releve is a core releve used to derive the classification; N if releve is not a core releve used to derive the classification but has been assigned statistically to a VEG_TYPE on the basis of best-fit; N/A if releve is not assigned to a VEG_TYPE. X_coord: X-coordinate of the point. Y_coord: Y-coordinate of the point.

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