Identification info

Metadata Language

English

Character set

UTF8

Dataset Reference Date (Creation)

2010-06-30

Dataset Reference Date (Publication)

2016-03-31

Identifier

/ SMSS

Maintenance and update frequency

Unknown

GEMET - INSPIRE themes, version 1.0

• Habitats and biotopes

• Protected sites

Limitations on Public Access

Other restrictions

Other constraints

Available under the Open Government Licence.

Acknowledgment: Contains NatureScot information licensed under the Open Government Licence v3.0

Use constraints

Other restrictions

Other constraints

none

Spatial representation type

Vector

Distance

10  m

Topic category

• Environment

 

Reference system identifier

EPSG / OSGB 1936 / British National Grid (EPSG:27700) / 7.9

Reference system identifier

EPSG / ETRS89 (EPSG:4258) / 7.9

Distribution Information

 

Data quality info

Quality Scope

Dataset

Statement

A database of point locations of saltmarsh habitat was created using information from existing datasets held by SNH and SEPA. The most relevant datasets were the range of reports and maps available from the Saltmarsh Survey of Great Britain (Burd 1989); the Sand Dune Vegetation Survey of Scotland (Dargie 2000b); the SNH report on the distribution of coastal habitats (Posford Duvivier 1998); and the Cycle 1 Site Condition Monitoring reports (Hutcheon Brothers 2000). These sites were analysed by NatureBureau and any sites which were over 3ha in area were included in the saltmarsh survey. The SSS identified a total of 255 sites requiring survey, including all point data sites over 3ha in extent; all polygon sites over 3ha in extent; and a representative set of 25 sites less than 3ha in extent, and 10 perched saltmarsh sites. Habitat maps were drawn onto aerial photography at a standardised scale of 1:4,000. (1:2,500 Scale Raster Getmapping Vertical Aerial Photography - 1km x 1km tiles (2003-2009))

Due to the wide variation of mapping units on different coastlines (e.g. large uniform areas of saltmarsh on the Solway Firth and small, but complex community structures on small sites in the west) it was concluded that there would be no set minimum mapping unit. Instead the scale of mapping was set to 1:4,000, thus the resolution of mapping was dictated by the resolution of the aerial photography. Mosaics were mapped using an estimation of the cover of each component as a proportion out of ten. This means that for each mapped area of a mosaic, all the constituent components will total up to ten portions, being the total area of the mapped polygon. More details about the NVC survey are available in the published report - https://www.nature.scot/snh-commissioned-report-786-scottish-saltmarsh-survey-national-report

Field map digitisation was overseen or undertaken by field surveyors to ensure the accuracy of the maps was maintained. The technique used to digitise maps evolved and became faster as the project progressed. The preferred method used through 2011 to 2013 was to trace polylines onto the GIS platform with a matched back drop and scale to the original field map. NVC community types and other land cover codes were added into the GIS attribute table once individual polygons were created.

The attribute table provides valuable information about each saltmarsh polygon including

SITE_NAME – example Eden Estuary

SITEID – example 001EDE

POLYID – example 001EDE001

SALTMARSH_ – example SM8.

Can include mosaics proportions given.

CATEGORY - Broad category NVC and land cover types – example SM NVC and land cover types used in this dataset are

• A – NVC aquatic grouping

• BBG – Buildings and bare ground

• BM – Bare mud

• BR – Bare rock

• BS – Bare sand

• BSH – Bare shingle

• fal jap - Fallopia japonica community

• H - Broad NVC community

• Iri pse - Iris pseudacorus community

• M - NVC Mire grouping

• MG - NVC Mesotrophic grassland grouping

• Mosaic

• OV - NVC Open vegetation community

• OW – Open water

• S - NVC Swamp community

• SD - NVC Sand dune vegetation

• SM – Saltmarsh

• U - NVC Acid grassland grouping

• W - NVC Woodland grouping

A full list of NVC and land cover codes from the SSS surveys is given in the Scottish saltmarsh survey national report Table 3-1 https://www.nature.scot/snh-commissioned-report-786-scottish-saltmarsh-survey-national-report

Area and perimeter County – example Angus Coordinates of the centre of each polygon Date of survey – example 14/06/2010 Surveyor name – example T.Haynes The attribute table for the GIS database includes a field Map_Legend for keying out colours in a map legend. A Dominant NVC field has been added which is the NVC community or land cover code from Saltmarsh_ or the largest component of a mosaic.

 

Metadata

File identifier

94e8b6f5-f2f4-43b8-8d02-7322b726c654 XML

Metadata Language

English

Resource type

Dataset

Metadata Date

2023-07-20T13:32:49

Metadata standard name

UK GEMINI

Metadata standard version

2.3