Extent of natural ecosystems

Extent of component ecosystem types

Extent figures are presented in Table 2 for the component ecosystem types that contribute to the total area figures (see Table 1). Caveats and limitations accompanying the figures are set out below, and further information on each type is given in the Technical Documentation. They are based on the IUCN Global Ecosystem Typology (GET) (Keith et al. 2020), which is a comprehensive classification framework for Earth’s ecosystems that integrates their functional and compositional features and forms an accepted international standard under several United Nations Conventions. Descriptions of the component ecosystems are available on the Global Ecosystem Typology website. In the typology they are called Ecosystem Functional Groups (EFGs) (or GET Level 3 types), rather than ecosystem types as used for this indicator. Anthropogenic EFGs have been excluded.

The ecosystems shown in Table 2 cover a wide range of types across UK marine and terrestrial environments. They include very extensive types, such as TF1.6 Boreal, temperate and montane peat bogs and M1.7 Subtidal sand beds, and others that are very limited in extent, such as F2.3 Seasonal freshwater lakes and M1.10 Rhodolith/Maërl beds. Note that some of the marine types overlap with each other (as is explained in the Technical Documentation and therefore the extent figures in Table 2 add up to more than the headline figures given in Table 1.

Table 2: Area of component ecosystem types

UK terrestrial ecosystems

UK marine ecosystems

Source: multiple sources, as set out in the Technical Documentation

Notes about Table 2

• The component ecosystem types listed in this table contribute to the extent figures presented in Table 1.
• The extent figures add up to more than the headline figures given in Table 1 because some of the marine ecosystem types overlap.
• The types are based on the Global Ecosystem Typology – they exclude anthropogenic Ecosystem Functional Groups.
• The alphabetic codes used in the first column refer to four GET biosphere realms: F = freshwater, S = subterranean, M = marine, T = terrestrial).
• Marine ecosystem types that overlap with each other are marked with an asterisk (*).
• The landward limit of marine ecosystems is based on the mean-high water mark and the overall extent is based on the area of the UK Exclusive Economic Zone (EEZ), as specified in the Metadata Factsheet for Indicator A.2 Extent of natural ecosystems – note that this does not include the entirety of the UK continental shelf.
• Caveats and limitations accompanying these figures are set out below.

Relevance

Natural and semi-natural ecosystems are of most importance for nature conservation. They are the foundation of biodiversity, providing the conditions necessary for a wide array of life forms to coexist and thrive. Their conversion to other ecosystem/ habitat/ land-use types, typically driven by human activities such as urban development, agricultural intensification, infrastructure development, forestry, draining or neglect, is one of the main drivers of biodiversity loss and is reflected in the reduction of the area of such ecosystems. Conversely, ecological restoration efforts can result in increases in their area.

This indicator aims to show the extent of natural and semi-natural ecosystems and track changes over time. It can be disaggregated into different ecosystem types, providing insights into the relative abundance and changes of specific ecosystem types.

International/domestic reporting

The suite of UK Biodiversity Indicators has been revised and updated to bring it in line with the Kunming-Montreal Global Biodiversity Framework of the Convention on Biological Diversity (CBD). Some UKBIs will be used for the forthcoming UK national reports to CBD.

This indicator links to GBF Goal A ‘Protect and Restore’ and Target 1 ‘Plan and Manage all Areas to Reduce Biodiversity Loss’.

Web links for further information

• Kunming-Montreal Global Biodiversity Framework
• Global Ecosystem Typology
• Indicators for the Kunming-Montreal Global Biodiversity Framework – Metadata Factsheet for Indicator A.2 Extent of natural ecosystem

Methodology

The extent figures used for this indicator were informed by expert advice from habitat specialists in Natural England, Natural Resources Wales, NatureScot, DAERA and JNCC. This includes the scope of the component ecosystem types, their correspondence with UK habitat and vegetation classifications, and the most reliable sources of data on ecosystem extent. Full details of the methodology are provided in the Technical Documentation.

Caveats and limitations

The extent figures for the component ecosystem types in Table 2 are based on the best available information and availability of resources to conduct analyses. Nevertheless, they should be treated as estimates, accompanied by varying degrees of certainty and accuracy, rather than precise values.

The ecosystems assessed are intended to include all natural and semi-natural ecosystems in the UK. However, in a limited number of cases, the extent figures are based on a minimum value or exclude a significant area/part of the type – this has a very small impact on the extent figures presented in Tables 1 and 2. UK habitat types that are not or are only partially accounted for include: arable field margins; endolithic systems; fens; groundwater ecosystems; hedgerows; large seabird colonies on non-coastal cliff sites and large seal colonies; open ocean waters; open mosaic habitats on previously developed land; ponds and other small waterbodies; rivers and streams; subterranean caves/streams/pools; traditional orchards; and wood-pasture and parkland. Further details, including which GET Ecosystem Functional Groups have not been included, are set out in the Technical Documentation.