B6: Natural functions of water and wetland ecosystems

Short Description

This indicator will track changes in the naturalness of ecosystem functioning across water and wetland ecosystems in England, based on a range of attributes indicating levels of artificial modification. Restoring natural functions to these ecosystems is essential for biodiversity recovery and resilience to climate change and contributes to enhancing ecosystem services such as the provision of clean water and flood regulation.

The indicator will cover rivers, headwater streams, lakes, ponds, wetlands, estuaries and coasts, characterising the naturalness of hydrological, physical, chemical and biological functions. It uses data from a range of sources, aggregated together in a single hierarchical data framework that serves both high-level reporting needs and detailed biodiversity reporting on individual habitat types (such as chalk streams/rivers and oligotrophic lakes).

The data framework for this indicator enables strategic reporting of the condition or quality of water-related habitats, with respect to nature recovery generally and the favourable conservation status of detailed habitat types. It feeds into broader assessment of the extent, quality and connectivity of habitats under Indicator D1.

Readiness and links to data

This indicator is not available for reporting in 2024 in a finalised form. An interim indicator is presented here that presents data on a subset of the ecosystems that B6 will ultimately cover. A headline dashboard is provided, completed with interim data for freshwater ecosystems (rivers, streams, lakes and ponds) only. Further detail on the hierarchical assessment framework servicing this indicator is provided in the B6 information pack on the Discovering priority habitats in England website. This includes a more detailed dashboard of habitat types, further detail on the assessment of rivers, streams, lakes and ponds, and example assessments of some of the detailed habitat types on which the framework will eventually enable reporting.

Work is ongoing to refine the datasets used for rivers, streams, lakes and ponds and add assessments of wetlands, estuaries and coasts. In the past year attributes for estuaries and coasts have been defined and populated with available data, and conceptual thinking on wetland habitats has been progressed. Detailed B6 progress reports are provided on the Discovering priority habitats in England website.

The B6 data framework is being packaged up so that it can move from the development phase to an operational phase. The detailed information pack supporting this interim version of the indicator includes information on data sources, attribute definition and data processing. Operationalising the indicator to provide assessment of trends is a significant undertaking because of the variety of data sources, data types and data processing involved.

Notes on indicator

Data from a large number of individual attributes, from different sources, feed into the headline dashboard presented here. Each attribute has its own issues relating to data availability, spatial coverage and representativeness, and confidence. The B6 information pack on the Discovering priority habitats in England website provides further information on individual attributes. Detailed outputs within the information pack describe data caveats and limitations relating to individual habitat types.

Indicator components

Table B6: Naturalness scores of water and wetland ecosystems in England, 2022

Broad habitat Habitat type Naturalness component Class Score
Estuaries/coasts Coastal Biological - -
Estuaries/coasts Coastal Chemical - -
Estuaries/coasts Coastal Crosscutting - -
Estuaries/coasts Coastal Hydrological - -
Estuaries/coasts Coastal Overall - -
Estuaries/coasts Coastal Physical - -
Estuaries/coasts Estuaries Biological - -
Estuaries/coasts Estuaries Chemical - -
Estuaries/coasts Estuaries Crosscutting - -
Estuaries/coasts Estuaries Hydrological - -
Estuaries/coasts Estuaries Overall - -
Estuaries/coasts Estuaries Physical - -
Running waters Headwater streams Biological 2.00 2.15
Running waters Headwater streams Chemical 2.00 2.42
Running waters Headwater streams Crosscutting 4.00 3.74
Running waters Headwater streams Hydrological 3.00 2.61
Running waters Headwater streams Overall 3.00 2.80
Running waters Headwater streams Physical 3.00 3.06
Running waters Large rivers Biological 3.00 2.69
Running waters Large rivers Chemical 2.00 1.74
Running waters Large rivers Crosscutting - -
Running waters Large rivers Hydrological 3.00 2.47
Running waters Large rivers Overall 3.00 2.50
Running waters Large rivers Physical 3.00 3.12
Standing waters Lakes Biological 4.00 4.36
Standing waters Lakes Chemical 2.00 2.29
Standing waters Lakes Crosscutting - -
Standing waters Lakes Hydrological 3.00 2.51
Standing waters Lakes Overall 3.00 2.99
Standing waters Lakes Physical 3.00 2.80
Standing waters Ponds Biological 3.00 3.55
Standing waters Ponds Chemical 3.00 2.53
Standing waters Ponds Crosscutting - -
Standing waters Ponds Hydrological - -
Standing waters Ponds Overall 3.00 3.00
Standing waters Ponds Physical 3.00 2.92
Wetlands Bogs Biological - -
Wetlands Bogs Chemical - -
Wetlands Bogs Crosscutting - -
Wetlands Bogs Hydrological - -
Wetlands Bogs Overall - -
Wetlands Bogs Physical - -
Wetlands Fens Biological - -
Wetlands Fens Chemical - -
Wetlands Fens Crosscutting - -
Wetlands Fens Hydrological - -
Wetlands Fens Overall - -
Wetlands Fens Physical - -

Image B6: Naturalness scores of water and wetland ecosystems in England, 2022

Trend description for B6

The 4 currently assessed habitat types; Large Rivers, Headwater Streams, Lakes, and Ponds each have a combined naturalness classification of 3, which breaks down to an average combined score of 2.5, 2.8. 2.99 and 3 respectively. The breakdown of these scores into the individual components highlights that each habitat has been subject to a range of artificial modification within each of the various naturalness components. While all the habitats that have available data are shown to have a classification of 3 for their hydrological and physical components, the other components show greater variation between habitat types. The lowest score (worst in ecological terms) across the habitats is given to the biological component of lakes with a score of 4.36 (Class 4). In comparison, the highest score (best in ecological terms) was achieved by the chemical component of the large rivers habitats with a score of 1.74 (Class 1).

Assessment of change

No assessment of change was undertaken for this indicator as a suitable time series is not yet available in the Outcome Indicator Framework.

Indicator Metadata