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The Broadscale Mapping Project has been devised and funded by a consortium consisting of the Crown Estate, the Countryside Council for Wales, English Nature, Scottish Natural Heritage and the SeaMap research group based at Newcastle University and undertaken by SeaMap. Three trial areas were selected, around Milford Haven, Pembrokeshire and South Cardigan Bay, for developing and testing the methodology, although experience from many other surveys conducted by SeaMap have also contributed to the development of the methodology. The aim of this data collection was to map the seafloor sediments and biota, for habitats and biotope mapping. This was supplemented by maps and supporting data showing the location of ground truth samples and the positions of the acoustic tracks.
Natural Resources Wales (NRW)
There are no access restrictions to this data. NRW may release, publish or disseminate it freely.
| Other details | ||
| Internal code | Internally assigned metadata identifier | 1884 |
| Title | The title is used to provide a brief and precise description of the dataset such as 'Date', 'Originating organisation/programme', 'Location' and 'Type of survey'. All acronyms and abbreviations should be reproduced in full. | Broadscale Remote Survey and Mapping of Sublittoral Habitats and Biota of Milford Haven, Pembrokeshire and South Cardigan Bay |
| Alternative title | The purpose of alternative title is to record any additional names by which the dataset may be known. | Arolwg o bell a mapio graddfa eang cynefinoedd a biota isarforol Aberdaugleddau, Sir Benfro a de Bae Ceredigion |
| File Identifier | The File Identifier is a code, preferably a GUID, that is globally unique and remains with the same metadata record even if the record is edited or transferred between portals or tools. | 4f4c4942-4343-5764-6473-313130303337 |
| Resource Identifier | This is the code assigned by the data owner. | 110037 |
| Resource type | The resource type will likely be a dataset but could also be a series (collection of datasets with a common specification) or a service. | dataset |
| Start date | This describes the date the resource starts. This may only be the year if month and day are not known | 1994-01-01 |
| End date | This describes the date the resource ends. This may only be the year if month and day are not known | 1998-12-31 |
| Spatial resolution | This describes the spatial resolution of the dataset or the spatial limitations of the service. | inapplicable |
| Frequency of updates | This describes the frequency with which the resource is modified or updated i.e. a monitoring programme that samples once per year has a frequency that is described as 'annually'. | notPlanned |
| Abstract | The abstract provides a clear and brief statement of the content of the resource. | The Broadscale Mapping Project has been devised and funded by a consortium consisting of the Crown Estate, the Countryside Council for Wales, English Nature, Scottish Natural Heritage and the SeaMap research group based at Newcastle University and undertaken by SeaMap. Three trial areas were selected, around Milford Haven, Pembrokeshire and South Cardigan Bay, for developing and testing the methodology, although experience from many other surveys conducted by SeaMap have also contributed to the development of the methodology. The aim of this data collection was to map the seafloor sediments and biota, for habitats and biotope mapping. This was supplemented by maps and supporting data showing the location of ground truth samples and the positions of the acoustic tracks. |
| Lineage | Lineage includes the background information, history of the sources of data, data quality statements and methods. | Image processing requires ground truth samples of the biota and habitats from the sea floor and the sampling techniques range from the traditional grab, trawl and dredge to the deployment of remote video. The video is especially useful since it provides a vista of the sea floor which is approximately of the same extent as the area of the seafloor that is covered by one pulse from an echo sounder (the 'footprint'). Image processing is a two-stage process: In the first stage the acoustic data in the immediate vicinity of the ground truth positions are selected and tagged according to the type of habitat or biotope of the ground truth sample. The acoustic data are pooled for each habitat or biotope type and the acoustic characteristic calculated from th e mean and standard deviation of the depth and the hardness and roughness values. In this way an acoustic signature is created for each habitat or biotope type. In the second stage each pixel is matched to the signatures and the likelihood of the pixel belonging to each habitat or biotope calculated. An automated process then selects the most likely category for the pixel. This second stage is, therefore, called a maximum likelihood classification. The methodology relies on the relatively inexpensive acoustic ground discrimination system (AGDS) based on a single beam echo sounder. AGDS analyse the echo from the sounder and gives a measure of the hardness and roughness of the sea floor, as well as depth. These records, in the form of point data, are logged together with time and position a s the vessel tracks over the survey area. The point data are used to create continuous digital images for each of the variables through interpolation. This conversion to digital images consisting of rows and columns of pixels enables powerful image processing software, designed primarily for the processing of satellite images, to be applied to the acoustic data. |
| Related keywords | ||
| Keyword | General subject area(s) associated with the resource, uses multiple controlled vocabularies | Environmental monitoring facilities |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | Habitat characterisation | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | Marine Environmental Data and Information Network | |
| Geographical coverage | ||
| North | The northern-most limit of the data resource in decimal degrees | 52.61247764 |
| East | The eastern-most limit of the data resource in decimal degrees | -4.02399813 |
| South | The southern-most limit of the data resource in decimal degrees | 51.43965144 |
| West | The western-most limit of the data resource in decimal degrees | -5.46850994 |
| Regional sea | Wales (WLS) | |
| Responsible organisations | ||
| Role | The point of contact is person or organisation with responsibility for the creation and maintenance of the metadata for the resource. | pointOfContact |
| Organisation name | Natural Resources Wales (NRW) | |
| Phone | 0300 065 3000 | |
| Delivery point | Maes-y-Ffynnon | |
| Postal code | LL57 2DW | |
| Role | The distributor is the person or organisation that distributes the resource. | distributor |
| Organisation name | Natural Resources Wales (NRW) | |
| Phone | 0300 065 3000 | |
| Delivery point | Maes-y-Ffynnon | |
| Postal code | LL57 2DW | |
| Role | The custodian is the person or organisation that accepts responsibility for the resource and ensures appropriate care and maintenance. If a dataset has been lodged with a Data Archive Centre for maintenance then this organisation is be entered here. | custodian |
| Organisation name | Natural Resources Wales (NRW) | |
| Phone | 0300 065 3000 | |
| Delivery point | Maes-y-Ffynnon | |
| Postal code | LL57 2DW | |
| Role | The originator is the person or organisation who created, collected or produced the resource. | originator |
| Organisation name | Newcastle University | |
| Phone | +44 (0) 191 222 6000 | |
| Postal code | NE1 7RU | |
| Dataset constraints | ||
| 20 Limitations on Public Access - Access constraints | ISO restriction code chosen from ISO 19115-1 Codelist | otherRestrictions |
| 20 Limitations on Public Access – Other constraints | Any restriction on the use of the resource such as the need to agree to certain licence conditions. | There are no access restrictions to this data. NRW may release, publish or disseminate it freely. |
| 21 Conditions for Access and Use - Use limitation | Any restrictions imposed on accessing the resource such as the need to agree to certain licence conditions. | © CNC/NRW 1999. 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. |
| Available data formats | ||
| Data format | Format in which digital data can be provided for transfer | Geographic Information System |
| Version info | ||
| Date of publication | The publication date of the resource or if previously unpublished the date that the resource was made publicly available via the MEDIN network. | 1999-12-31 |
| Date of last revision | The most recent date that the resource was revised. | 1999-12-31 |
| Metadata date | The date when the content of this metadata record was last updated. | 2018-07-03 |
| Metadata standard name | The name of the metadata standard used to create this metadata | MEDIN Discovery Metadata Standard |
| Metadata standard version | The version of the MEDIN Discovery Metadata Standard used to create the metadata record | Version 2.3.8 |
© OpenStreetMap contributors