Metadata Factsheet

3. Goals and Targets addressed

3a. Goal

Headline Indicator for Goal A: The integrity, connectivity and resilience of all ecosystems are maintained, enhanced, or restored, substantially increasing the area of natural ecosystems by 2050; Human induced extinction of known threatened species is halted, and, by 2050, the extinction rate and risk of all species are reduced tenfold and the abundance of native wild species is increased to healthy and resilient levels; The genetic diversity within populations of wild and domesticated species, is maintained, safeguarding their adaptive potential.

3b. Target

Headline Indicator for Target 1: Ensure that all areas are under participatory integrated biodiversity inclusive spatial planning and/or effective management processes addressing land and sea use change, to bring the loss of areas of high biodiversity importance, including ecosystems of high ecological integrity, close to zero by 2030, while respecting the rights of indigenous peoples and local communities.

5. Definitions, concepts and classifications

5a. Definition

Indicator definition:

14. The indicator, at the national level, is defined as the extent of natural and semi-natural ecosystems as a proportion of total area of the country at a particular point in time, expressed as a percentage. The point in time is the closing date of the accounting period for which the ecosystem accounts were compiled. Trends over time will be evident from changes in the proportion of total area over successive accounting periods. 15. The total surface area of a country includes land, inland water and, if applicable, marine area to the end of the exclusive economic zone. For countries with marine territory, the indicator should ideally be compiled for both inland and marine area. However, it could be compiled only for the inland area if data on the distribution of marine ecosystems are not yet available. Subterranean areas are currently out of scope of the indicator. 16. It is recognised that the indicator does not capture information about ecosystems in the high seas (i.e. areas beyond national jurisdiction).

Other key concepts and definitions:

17. The concepts, definitions and classification used are based on the SEEA Ecosystem Accounting (United Nations et al. 2021) and the International Union for the Conservation of Nature’s Global Ecosystem Typology (IUCN GET). These can be complemented by national ecosystem classifications used in ecosystem accounting.

18. An ecosystem is defined by the CBD as a dynamic complex of plant, animal and microorganism communities and their non-living environment interacting as a functional unit (CBD, 1992, Article 2). The SEEA EA uses the CBD definition of ecosystems. Important elements of this definition are the biotic (living) component, the abiotic (non-living) component and the interactions among the biota and between the biotic and abiotic components. Alongside this definition, three attributes of ecosystems are often identified: composition, structure and function. Composition relates to the suite of species that occur within the ecosystem, structure to the physical structure and patterns of the ecosystem, and function to ecological processes. (Global Ecosystems Atlas, 2025)

19. For many real-world applications, it is useful to divide the ecosystems that occur in a continuous landscape or seascape into different ecosystem types that can be used for planning, decision making, management and monitoring (Keith et al., 2015). An ecosystem type is defined as a type of ecosystem distinguished from other types by its characteristic functional, structural and compositional properties (IUCN, 2025). An ecosystem type is identified and delineated as part of a classification system for ecosystems, often hierarchical, based on biotic and abiotic factors.

20. In classifying and mapping ecosystem types, it is important that compositional, structural and functional attributes are all considered in identifying and distinguishing between ecosystem types. This allows ecosystem types to be identified as ecologically meaningful units that are consistent with the concept of an ecosystem as defined by the CBD.

21. Ecosystem extent is the size of an ecosystem asset, where ecosystem assets are defined as contiguous spaces of a specific ecosystem type characterized by a distinct set of biotic and abiotic components and their interactions (United Nations 2021). An ecosystem type may have several occurrences (i.e. be made up of several ecosystem assets) interspersed with occurrence of other ecosystem types in the landscape or seascape. The combined extent of all the ecosystem assets make up the extent of that ecosystem type.

22. The total area for which ecosystem accounts are compiled is called the ecosystem accounting area. For the purposes of accounting, ecosystem types must be delineated to be spatially mutually exclusive and comprehensive across the ecosystem accounting area (i.e. no overlaps or gaps between ecosystem types and wall-to-wall coverage of the whole ecosystem accounting area). The total area is the sum of the areas of all ecosystem types in that area including natural and anthropogenic ecosystem types. For the purposes of this indicator, the ecosystem accounting area should be the total area of the country. For countries that have marine territory, the total surface area of the country could be divided into separate ecosystem accounting areas, for example one for the inland area (including land and inland waters)and another for the marine area. Regardless of whether ecosystem accounts are developed for the inland and marine area as a single ecosystem accounting area or as two separate ecosystem accounting areas, the indicator should be reported in two components: an inland component and a marine component, as explained in paragraph 39. For both the inland and marine components, countries should report the total area in absolute terms, not only the area of natural ecosystems, as this provides the denominator for the indicator.

23. Changes in extent of natural ecosystems occur primarily through ecosystem conversion. In the SEEA Ecosystem Accounting, ecosystem conversions refer to situations in which, for a given location, there is a change in ecosystem type involving a distinct and persistent change in the ecological structure, composition and function which, in turn, is reflected in the supply of a different set of ecosystem services. This definition aligns well with the approach to loss of ecosystem area (leading eventually to ecosystem collapse) in the Red List of Ecosystems.

24. Reduction in the extent of natural ecosystems will be tracked primarily through measuring conversion of area within natural ecosystems types to anthropogenic ecosystems types. There are also instances in which the extent of natural ecosystems may increase, for example through restoration of anthropogenic ecosystems towards a natural state.

25. Ecosystem types are ideally classified at the national level as part of a national ecosystem classification system. The IUCN GET (Keith et al. 2020), is the reference classification for ecosystem types in the SEEA Ecosystem Accounting and was endorsed by the United Nations Statistical Commission at its 55th session in March 2024 as an international statistical classification system. . The GET is a hierarchical classification, enabling global consistency at the aggregate levels while encouraging detailed national ecosystem classifications at the more detailed levels. The three upper levels of IUCN GET – realms, biomes and ecosystem functional groups – classify ecosystems based on their functional characteristics (such as structural roles of foundation species, water regime, climatic regime or food web structure). National ecosystem types would typically be identified at level 5 or 6, which include emphasis on compositional characteristics and are intended to be developed bottom-up by countries. Level 3 – ecosystem functional groups (EFGs) – of the IUCN GET an important level for comparing information across countries and synthesising ecosystem related information. As discussed in paragraph27, countries are encouraged to cross-reference their national ecosystem classifications to EFGs for the purposes of global comparison and reporting.

26. Natural ecosystems are ecosystems in which the impacts of humans on ecosystem composition, structure and function are low compared to natural factors. In this broad sense, natural ecosystem types include:

(a) Ecosystems influenced or modified to varying degrees by human interventions, but with natural compositional, structural and functional characteristics still at least partially present and recognisable. The human interventions could be beneficial, neutral or negative from a biodiversity perspective. In some cases, the human intervention may mimic processes that would have taken place as part of the natural functioning of the ecosystem prior to human modification (e.g. grazing by wild herbivores or natural fire cycles). It may include the use of ecosystems by traditional and/or Indigenous societies, including practices such as fire management, nomadic grazing and other pastoral practices. In some contexts, these modified ecosystems are termed semi-natural.

(b) Instances of natural ecosystem types that are in a range of condition states, from pristine ecosystems in excellent condition or with high integrity, through to those in poor condition, degraded, or with low integrity.

27.

28. In contrast, anthropogenic ecosystem types are those created and maintained through human interventions, i.e. human interventions are the primary determinant of the composition, structure and functioning of the ecosystem. An anthropogenic ecosystem type has typically replaced an antecedent or pre-existing natural ecosystem type, which is no longer recognisably present (although small patches/fragments and some native species may persist). Human intervention does much more than influence or modify the ecosystem, even substantially. It determines the compositional, structural and functional characteristics of the ecosystem, and is typically essential for maintaining those characteristics. The human interventions that create anthropogenic ecosystems are frequently connected to land- and sea-use systems that maintain modern-day industrial societies.

29. For the purposes of this indicator, natural and anthropogenic ecosystems are identified based on the EFGs of the IUCN GET. Of the 25 biomes in the GET, six are considered anthropogenic, containing 16 EFGs. Setting aside the subterranean biomes, which are out of scope of Indicator A.2, leaves 20 biomes of which four are anthropogenic, containing 13 EFGs. The anthropogenic EFGs are listed in Table 1.

.Please refer to the IUCN GET (Keith et.al 2020) for detailed descriptive profiles for each EFG, which can also be found at https://global-ecosystems.org/.

The IUCN GET is also used for summarising and disaggregation in Headline Indicator A1, the Red List of Ecosystems, which focuses on the risk of collapse of natural ecosystems.

5b. Method of computation

30. The indicator is drawn directly from ecosystem extent accounts compiled based on the SEEA Ecosystem Accounting framework, which organize data on the extent of different ecosystem types. An ecosystem extent account records the extent (area) and changes in extent, for all ecosystem types within an ecosystem accounting area (in this case a country), including natural, and anthropogenic ecosystem types.8 A stylized example of an ecosystem extent account is shown in Table 2, where the opening extent, closing extent, and additions and reductions in extent and net change in extent for each ecosystem type are recorded for a particular accounting period. The “total” column must reflect the extent of the whole Ecosystem Accounting Area (in this case the total inland area or total marine area of the country). Entries are in measurement units such as hectares or square kilometres. Ideally accounts are compiled for successive accounting periods, with the closing extent for one accounting period becoming the opening extent for the next accounting period. The critical elements of the account table for reporting on the indicator are the opening extent of the first accounting period, the closing extent of the first and each subsequent accounting period and the total extent of the country (see Section 6d.3).

31. More comprehensive versions of the ecosystem extent account table than the one shown in Table 2 are also possible (e.g. see Table 4.1 in SEEA EA), and a change matrix can be compiled alongside the extent account (described in SEEA EA), providing additional information about conversions between different ecosystem types.

Table 2 Stylized ecosystem extent account (units of area)

32. Countries that have their own national classification system and maps for ecosystems should use that classification and spatial data for the compilation of extent accounts. The accounts can be compiled in as much detail as needed at the national level, for example at a level equivalent to Levels 5 or 6 of the GET (these levels are intended to be developed bottom-up, from the national or local level).

33. In such cases, cross reference of this national classification system with IUCN GET Level 3 (EFGs) should be developed to facilitate consistency and comparison across countries. Each national ecosystem type should be cross-referenced to one or more EFGs with similar characteristics based on the descriptions of the EFGs and other relevant information. See the IUCN’s standards, methods and guidelines for cross-referencing ecosystem classifications and maps to the IUCN Global Ecosystem Typology (IUCN, 2025).

34.It is important to note that the cross-referencing from national ecosystem types to EFGs is a conceptual cross-reference not a spatial cross-walk. Countries should use their own spatial data on the distribution of ecosystem types (cross-walked to EFGs) for compiling the extent account, not, for example, the indicative spatial data on distribution of EFGs that is available on the GET website.

35. If no national ecosystem extent accounts exist yet, other sources of information on ecosystem extent may support reporting on Indicator A.2. These include using extent estimates from national ecosystem maps directly, or from Red List of Ecosystem assessments used in Indicator A.1 (which are typically underpinned by data on ecosystem extent and changes in extent). However, ecosystem accounts provide a consistent structure for estimating extent, and thus are recommended for calculating Indicator A.2.

36. When no existing national classification and/or map of ecosystem types is available, or deemed suitable for reporting, a country could opt to use global data or tools to compile extent accounts. The compilation guidelines for Indicator A.2 provide further guidance on key national datasets required for the indicator as well as using global datasets as an interim option if national datasets are absent or only partially developed.

37. Once national ecosystem types have been cross-referenced to the EFGs in the GET, the extent account table based on national ecosystem types should be translated to an extent account based on GET EFGs. In some cases this will involve aggregating values for several national ecosystem types that fall within one EFG. The compilation guidelines for Indicator A.2 provide further guidance on translating an extent account based on national ecosystem types to EFGs.

38. The indicator, “extent of natural ecosystems as a proportion of total area”, is then obtained by summing the extent of the EFGs pertaining to natural ecosystems (in hectares or square kilometres) and dividing by total area of the country (in the same units). The denominator for the indicator must be the total area of the country (either total inland area or total marine area, as applicable), not only part of the area. The final indicator is expressed in percentage terms.

39. As noted in Section 4, total area of the country includes land area, inland water area and, where applicable, marine area (to the end of the exclusive economic zone). For countries with marine territory that do not yet have data on the distribution of marine ecosystem types, the indicator can be compiled only for total inland area and the associated EFGs. Further, because most marine ecosystems are natural or semi-natural, there is a risk that reporting a single combined indicator for inland and marine area could mask the extent of anthropogenic ecosystems in inland realms. Especially in countries with large marine territories, this could mask significant changes occurring in terrestrial and freshwater ecosystems. This means that the indicator should be reported separately for inland and marine areas (at the national and global level). The compilation guidelines for Indicator A.2 provide guidance on dealing with transitional realms (which include coastal ecosystems), including how they should be allocated to a country’s inland or marine area.

40. For reporting the indicator, countries will not be expected to submit the ecosystem extent account table. Rather, they will submit data on the extent of each EFG and the total country area in absolute terms (e.g. ha/km2). A globally aggregated indicator can then be obtained by summing the national values in absolute terms and converting them to proportions expressed in percentage terms. (See further discussion in Section 6d.)

5c. Data collection method

41. Also see Section 5e Data sources. The national ecosystem maps that underpin ecosystem extent accounts (which include ecosystem classification and spatial datasets representing the distribution of all ecosystem types in a country), and time series spatial datasets that show changes in extent of ecosystems, are developed based on a wide range of data sources which differ for different realms and have different collection methods. Remote sensing and earth observation data often play an important role, along with field data and expert knowledge.

42. When national data is not available, global data layers may be used where they are considered suitable.

5d. Accessibility of methodology

43. The United Nations Statistical Commission at its 52nd session in 2021 adopted the SEEA Ecosystem Accounting chapters 1-7 describing the accounting framework and the biophysical accounts, including chapters on ecosystem extent, as an international statistical standard. Existing SEEA EA resources can be drawn on in compiling accounts, including freely available e-learning resources (https://seea.un.org/content/seea-e-learning-resources. In addition, the Technical Committee on the SEEA Ecosystem Accounting is working on technical guidance notes on the compilation of ecosystem extent accounts (among others), which will assist countries in producing these accounts. Capacity development for Parties, especially for developing countries, should be provided to support the compilation of this indicator.

44. IUCN GET is a published and peer reviewed classification of global ecosystems which can be accessed at https://global-ecosystems.org/. 45. Additional compilation guidance for this indicator is being prepared through an expert process led by the UN Statistics Division. A draft is available on the meeting webpage for SBSTTA-28. The guidelines will be finalised by January 2027.

5e. Data sources

47. The main data requirements for this indicator are national ecosystem maps (including classification of ecosystem types and spatial datasets representing the distribution) and time series spatial data sets that show changes in extent of ecosystems. The compilation guidelines for headline indicator A.2 provide further guidance in this regard. Data sources could include research institutions, various government ministries and national mapping agencies.

48. In the absence of national data sources, regional and global datasets can be used, subject to criteria, standards and quality assurance, including validation at the national level through appropriate institutional processes involving relevant national experts. For example, ARIES for SEEA allows users to derive a basic ecosystem extent account (for the period from 1992) in the terrestrial, freshwater and coastal realms using a multilayer look-up table approach which combines global data sources on land cover and other metrics to approximate EFGs (https://seea.un.org/content/aries-for-seea). The Global Ecosystems Atlas (https://globalecosystemsatlas.org/), an initiative convened by the Group on Earth Observations (GEO), is compiling a standardised global map of EFGs at a 100m resolution from national or other peer-reviewed data sources, filling gaps using ecosystem classification geospatial models. Prior to being included in the Global Ecosystems Atlas, contributed data are screened according to quality criteria for recency, spatial resolution, and open re-use licenses. Where ecosystems are mapped using national classifications, the Global Ecosystems Atlas cross-references the data to the GET using IUCN standards, methods, and guidelines (IUCN, 2025). The distributions of ecosystems in otherwise unmapped territories are modelled using ecosystem classification geospatial models trained using EcoTrain (Murray et al. 2026), an expert-annotated training and validation dataset of more than 80,000 points globally. Once global coverage is complete, ecosystem extent information from the Global Ecosystems Atlas will be available to support the compilation of indicator A.2.

49. The compilation guidelines for Indicator A.2 provide further guidance on the use of global datasets as an interim measure. High-level guidance on data quality and validation is addressed in the compilation guidelines for headline indicator A.2.

5f. Availability and release calendar

50. The indicator methodology is based on SEEA Ecosystem Accounting, which is well developed and accepted by the international statistical community and other communities working on ecosystem accounting.

51. Since the adoption of the SEEA Ecosystem Accounting as an international statistical standard, an increasing number of countries have started the implementation of ecosystem extent accounts. According to the 2025 Global Assessment of Environmental-Economic Accounting and Supporting Statistics, 47 countries compiled ecosystem extent accounts at least once during the period 2021 to 2025 (United Nations, 2025).

52. For countries with no national data on ecosystem extent, global tools and databases could be drawn on, as discussed in Section 5e on data sources. These would require validation at the national level through appropriate institutional processes involving relevant national experts.

5g. Time series

53. Although it is ideal to compile ecosystem accounts on an annual basis, in practice this is seldom possible and may not be meaningful. For the ecosystem extent account, an update every three to five years may be sufficient and is likely to indicate actual changes in extent.

5h. Data providers

54. For those countries that have national ecosystem extent accounts, the relevant national authorities, in particular national statistical offices, ministries of environment or related agencies, will provide data for this indicator. In the absence of published national ecosystem extent accounts, a preliminary ecosystem extent account may be compiled using available national and/or global data sources Such a preliminary account would require national validation through appropriate institutional processes involving relevant national experts.

5i. Data compilers

55. For those countries that have national ecosystem extent accounts, the relevant national authorities, in particular the national statistical offices, ministries of environment or related agencies, will compile this indicator. In the absence of published national ecosystem extent accounts, a preliminary ecosystem account may be compiled using available national and/or global data sources. Such a preliminary account would require national validation through appropriate institutional processes involving relevant national experts.

5j. Gaps in data coverage

N/A

5k. Treatment of missing values

56. Missing values for individual countries may be estimated using global data platforms using existing global data. Such estimates would require national validation through appropriate institutional processes involving relevant national experts.

6. Scale

6a. Scale of use

Scale of application (please check all relevant boxes):

• Global: Yes
• Regional: Yes
• National: Yes

57. Scale of data disaggregation/aggregation:

• (a) Global/ regional scale indicator can be disaggregated to national level: Yes
• (b) National data is collated to form global indicator: Yes

58. The indicator is applicable at the global, national and regional scale. National data can be aggregated to form the global indicator provided that the underlying ecosystem classifications can be linked to IUCN GET, using the IUCN guidelines for such cross-referencing (IUCN, 2025).

6b. National/regional indicator production

59. The SEEA Ecosystem Accounting and IUCN GET are scalable at any level, including national and regional levels.

6c. Sources of differences between global and national figures

60. Differences between country produced and internationally estimated data may arise due to differences in spatial resolution of datasets, classification and mapping approaches, cross-walking approaches, projection, and definition of ecosystem conversion.

61. Differences may also arise due to territorial disputes between countries or in the case condominiums. These differences will be dealt with on a case-by-case basis.

6d. Regional and global estimates & data collection for global monitoring

6d.1 Description of the methodology

62. Regional and global estimates are produced by aggregating country-level data.

6d.2 Additional methodological details

63. Countries will provide data (using a spreadsheet template or through an online data collection system) that will request them to provide values in absolute terms (e.g. ha) for all EFGs in their country (see Section 6d.3 below). These values can then be aggregated globally and converted to percentages.

6d.3 Description of the mechanism for collecting data from countries

64. Data will be collected from countries (using a spreadsheet template or an online data collection system). As noted earlier, countries will not be required to submit their ecosystem extent account tables but rather to submit data extracted from the tables. Data on actual area in absolute terms is very useful, so the reporting template will require countries to report not only on proportions in percentage terms but also on the actual areas (e.g. in ha or km2). Countries will be requested to submit data on the extent of each EFG present in the country (natural and anthropogenic EFGs) at the end of each accounting period10 as well as the total area of the country. The sum of the area of all EFGs for each accounting period should equal the total area of the country (noting that inland and marine areas should be reported separately, if applicable, as discussed in Section 5a).11 Countries should identify the EFGs using the EFG codes and names from the GET Collecting data from countries disaggregated to EFGs allows for global aggregation to biomes or realms as needed.

65. The reporting template will allow countries to submit data for all the accounting periods for which they have compiled accounts. The first data point will be the opening extent of the first account compiled, followed by the closing extent for the first account and for each subsequent account, The opening extent of the first account provides a baseline for the country. Depending on the data available nationally, this could be the historical extent of the EFG, prior to major human modification of the landscape, or a more recent baseline.

66. Country baseline dates are distinct from the global baseline date. The proposed baseline year for global reporting under the GBF is likely to be 2020, or alternatively an average of the values between 2010 and 2020. Collecting data for years prior to the global baseline from countries that have such data could enable additional analyses that may be useful.

7. Other MEAs, processes and organisations

7a. Other MEA and processes

N/A

7b. Biodiversity Indicator Partnership

No

10. Data reporter

10a. Organisation

United Nations Statistics Division (UNSD)

10b. Contact person(s)

This meta-data sheet was prepared by UNSD, with contributions from members of the AHTEG and of the Task team of the UNCEEA Technical Committee on SEEA Ecosystem Accounting. Ilaria Di Matteo (dimatteo@un.org, seea@un.org),Environmental Economic Accounts Section of the UN Statistics Division