Mean Trophic Rank Data for rivers in Wales
Data'r Radd Droffig Gymedrig

  • English
  • wel
  • All

This dataset contains Mean Trophic Rank data for a selection of rivers in Wales. The purpose of this data capture was to assess the trophic status and eutrophication impact on rivers and streams using biotic indices. This is an old methodology and has now been superseded by LEAFPACKS. This dataset used to be supplied to former Countryside Council for Wales (CCW) by former Environment Agency Wales (EAW), both of whom now for part of Natural Resources Wales (NRW). This data is now currently held in the BIOSYS database where it can be extracted for internal use.

Identification

Dynodydd
Identifier
NRW_DS110241
Teitl Amgen
Alternative Title
Laith Metadata
Metadata Language
English
Lineage

Mean Trophic Rank, MTR is an assessment of trophic status and eutrophication impact on rivers and streams. The macrophyte flora and physical character of defined lengths (100m) of watercourse are surveyed using a standard checklist. The presence, absence and percentage area covered by each macrophyte are recorded. Each species is allocated a score (species trophic rank, STR) on a scale of 1-10 depending on its tolerance to eutrophication- the higher the score the lower the tolerance to nutrient enrichment. The scores of the species present are integrated as a mean value, weighted according to the relative percentage cover of individual species. The resulting value is the MTR score which increases with decreasing eutrophy. This methodology has now been superseded by LEAFPACKS, and the data is available in NRW's BIOSYS database.
Dyddiad cyfeirnod y set ddata (Creu)
Dataset Reference Date (Creation)
2024-05-28

Temporal Extent

Begin date
1960-01-01
 
Categori pwnc
Topic category
  • Inland waters
    Inland waters
  • Biota
    Biota
Perchennog
Owner
  Environment Agency (EA) -
Millbank Tower, 25th Floor, 21//24 Millbank, London, SW1P 4XL, England
http://www.environment-agency.gov.uk/
Perchennog
Owner
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Cychwynnwr
Originator
  Environment Agency (EA) -
Millbank Tower, 25th Floor, 21//24 Millbank, London, SW1P 4XL, England
http://www.environment-agency.gov.uk/
 

Extent

Extent

Hyd
Geographic Extent
Wales (WLS)
N
W
E
S
Map representing the geographic extent of the dataset


 
 

Distribution

Fformat - Math a Disgrifiad
Format Type and Description
  • Documents ( )

    Specification

    Excel spreadsheets

 

Quality

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

Mean Trophic Rank, MTR is an assessment of trophic status and eutrophication impact on rivers and streams. The macrophyte flora and physical character of defined lengths (100m) of watercourse are surveyed using a standard checklist. The presence, absence and percentage area covered by each macrophyte are recorded. Each species is allocated a score (species trophic rank, STR) on a scale of 1-10 depending on its tolerance to eutrophication- the higher the score the lower the tolerance to nutrient enrichment. The scores of the species present are integrated as a mean value, weighted according to the relative percentage cover of individual species. The resulting value is the MTR score which increases with decreasing eutrophy. This methodology has now been superseded by LEAFPACKS, and the data is available in NRW's BIOSYS database.
 

Keywords

Allweddair
Keywords

GEMET - INSPIRE themes, version 1.0
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2008-06-01
Code
geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Allweddair
Keywords

NRW Thesaurus
  • River Usk
  • eutrophication
  • macrophytes
  • trophic status
  • river Dee (afon Dyfrdwy)
  • river Gwyrfai (afon Gwyrfai)
  • rivers (see also specific river names)
  • River Wye (Afon Gwy)
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2026-08-27
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords
 

Spatial Reference System

Code
British National Grid (EPSG::27700)
 

Content

Gwybodaeth Cynnwys
Content Information

Proffil CNC
NRW Profile

Elfennau CNC
Custom Elements

 

Constraints

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 and Environment Agency Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and NRW's copyright. It is the recipient's responsibility to ensure the data is fit for the intended purpose.
 
 
 

Metadata

Metadata

Dynodydd Ffeil
File Identifier
4f4c4942-4343-5764-6473-313130323431 XML
Laith Metadata
Metadata Language
English
Math o adnodd
Resource type
Dataset
Dataset
Dyddiad Metadata
Metadata Date
2026-09-28T13:50:07.192Z
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

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