Metadata Factsheet

3. Goals and Targets addressed

3a. Goal

Headline indicator for Goal B: Biodiversity is sustainably used and managed and nature’s contributions to people, including ecosystem functions and services, are valued, maintained and enhanced, with those currently in decline being restored, supporting the achievement of sustainable development for the benefit of present and future generations by 2050.

3b. Target

Headline indicator for Target 11: Restore, maintain and enhance nature’s contributions to people, including ecosystem functions and services, such as regulation of air, water, and climate, soil health, pollination and reduction of disease risk, as well as protection from natural hazards and disasters, through nature-based solutions and/or ecosystem-based approaches for the benefit of all people and nature.

5. Definitions, concepts and classifications

5a. Definition

The proposed indicator is defined as the average rate of change in the provision of a set of ecosystem services in a particular time period compared to a baseline year, for a country or globally.

The concepts, definitions and classifications used in this indicator are based on the SEEA Ecosystem Accounting statistical standard that was adopted by the United Nations Statistical Commission in March 2021.1Ecosystem services are defined as the contributions of ecosystems to the benefits that are used in economic and other human activity, while benefits are defined as the goods and services that are ultimately used and enjoyed by people and society. For accounting purposes, the focus is usually on final ecosystem services only, which are those ecosystem services in which the user of the service is an economic unit – i.e., business, government or household2.

In ecosystem accounting, ecosystem services are conceptualised as flows between ecosystem assets and economic units. This results in an alignment between supply and use (i.e. supply needs to match use of a particular service), which is a foundational accounting concept. This means that an ecosystem service is recorded in the tables only when it is used. Explained differently, ecosystem services must actually be used to be included in the account, while ecosystem services that could potentially be used are excluded. For the purpose of this indicator the terms “supply of ecosystem services” and “ecosystem service supply” are avoided as they do not capture the use aspect of ecosystem services. Rather, the terms ecosystem service provision or provision of ecosystem services are used, with the intention of capturing the combination of supply and use that characterises ecosystem services in an accounting context. The account table follows a standard structure, shown in Table 7.1 of SEEA Ecosystem Accounting.

The total area for which the accounts are compiled is called the ecosystem accounting area. For the purposes of this indicator, the ecosystem accounting area should be the total area of the country.3 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 land and inland water area and another for the territorial waters (sea area to the end of the exclusive economic zone). Further guidance on this will be provided in compilation guidelines to be developed.

Ecosystem services are commonly grouped as provisioning, regulating and maintenance, and cultural services. SEEA Ecosystem Accounting includes a reference list of ecosystem services, grouped according to these broad categories, which has been adopted as part of the SEEA Ecosystem Accounting international statistical standard.4 There was detailed and extensive consultation on the development of this reference list and cross walks exist with all other major ecosystem services classifications. Within provisioning services, the SEEA Ecosystem Accounting reference list identifies ten sub-types of ecosystem services; within regulating services there are sixteen sub-types; and within cultural services there are five sub-types.

SEEA Ecosystem Accounting uses the IUCN’s Global Ecosystem Typology as the reference classification for ecosystem types, which was also endorsed by the United Nations Statistical Commission at its 55th session in March 2024 as an international statistical classification and recommended it to be included in the international family of classifications.5 Parties are able to use their national ecosystem classifications as the basis for their ecosystem accounts and ideally to cross-walk national ecosystem types to the Ecosystem Functional Groups (Level 3) of the Global Ecosystem Typology.

The biophysical ecosystem services accounts describe the flows of ecosystem services provided by ecosystem assets, grouped according to ecosystem type, in volume terms per accounting period. Metrics from the accounts are commonly in physical units such as cubic meters or tonnes. Indicators that can be derived from the account tables include percentage change over an accounting period or with respect to a baseline period.

The biophysical quantity for each ecosystem service may also be expressed in monetary terms where monetary valuation of the service is undertaken. Monetary valuation in an accounting context is approached differently to monetary valuation in environmental economics, and includes only exchange values rather than both exchange values and welfare values. The monetary ecosystem services accounts describe the ecosystem services provided by the ecosystem asset in monetary terms per accounting period, which can be aggregated to a single monetary value per accounting period. Indicators that can be derived from the account tables include percentage change in value over an accounting period or with respect to a baseline period.

5b. Method of computation

The indicator is computed in three stages: 1) selection of ecosystem services for inclusion in the indicator, 2) compilation of ecosystem services accounts, and 3) calculation of an aggregate index based on information from the accounts.

Stage 1 Selection of ecosystem system services to be included

The first stage in computing the indicator is to select ecosystem services that will be included in the indicator. As described above, the SEEA Ecosystem Accounting reference list of ecosystem services is used as the basis for the indicator and should thus be used in the selection of ecosystem services to be included in the indicator.

The selection of ecosystem services for this indicator takes a blended approach, reflecting both national and global priorities, based on the rationale explained in Section 4. The following starting point is used as the basis for the selection of ecosystem services by Parties for inclusion in the indicator at the national level:

• Required ecosystem services of global relevance to be included by all Parties (e.g., global climate regulation services (GCRS)).
• Recommended ecosystem services to be included by Parties from the SEEA Ecosystem Accounting reference list of ecosystem services, such that there is a combination of provisioning services, regulating services and cultural services. Alongside the recommended ecosystem services, there may also be a list of ecosystem services that Parties are discouraged from selecting.
• Parties may include additional ecosystem services that they consider important or policy relevant if they wish to.

From the recommended ecosystem services, Parties should select services based on a combination of importance or policy relevance of the service and data availability. In the selection of ecosystem services Parties should also consider the alignment and compatibility of the ecosystem service with the overall intent of the GBF, including the factors raised in the rationale in Section 4 related to dependence of people in vulnerable situations on the ecosystem service, its significance for indigenous peoples and local communities, whether it is possible to access if provision of the service is sustainable or not, whether the service is provided by anthropogenic ecosystem type(s) that impact negatively on biodiversity, the ease with which the contribution of the ecosystem to the service can be isolated and quantified, and the extent to which the service is already accounted for in standard economic measures. Relevance to Targets 9 and 11, for which ecosystem services accounts are also the basis for the headline indicator, should also be considered.

Compilation guidelines, to be developed, will provide additional guidance on selection of ecosystem services for inclusion in the indicator, including which services of global relevance are required to be included, the minimum (and potential maximum) number of services to be included per broad ecosystem service category, and more detail on factors to consider in the selection process.

Stage 2 Compilation of ecosystem services accounts

The second stage of developing the indicator is to compile accounts for each of the ecosystem services selected. The accounts should be compiled ideally at the national level, based on the SEEA Ecosystem Accounting. Methods for this are described in SEEA Ecosystem Accounting, with some supporting material already available (for example, SEEA e-learning resources | System of Environmental Economic Accounting) and more in development. For an example of an ecosystem services accounting table, see Table 7.1 in SEEA Ecosystem Accounting.

There may be some iteration between selection of ecosystem services and compilation of the accounts, as data needs and data availability for specific ecosystem services are determined.

Stage 3 Indicator calculation

The third stage of developing the indicator involves taking information from the ecosystem services accounts to develop an aggregate index of change in ecosystem service provision. Since, in physical terms, each ecosystem service is measured in a different unit, a simple summation across ecosystem services is not possible. Hence, an indicator that would allow aggregation across ecosystem services needs to be developed. Several options were identified, including aggregation of trends (rates of change) in quantitative terms using an averaging method, semi-qualitative approaches, and aggregation in monetary terms.

Based on initial exploration and testing experts converged that an aggregation method using a geometric mean of trends of ecosystem services seems to be the most viable option. The chain method for calculating the geometric mean has the advantage that it allows for different time series lengths with different starting years for different ecosystem services, which means that additional ecosystem services can be added to the index as datasets and accounts for additional ecosystem services become available. However, more testing and theoretical underpinning to justify such a choice is needed and will take place over the course of 2024 and 2025, ahead of the first reporting cycle scheduled for early 2026. Compilation of national ecosystem services accounts can proceed during this period.

In addition to a single aggregate index, three sub-indices, one for each broad category of ecosystem services (i.e., provisioning, regulating and cultural) should be calculated and reported. Because trends in provisioning, regulating and cultural ecosystem services often move in different directions, which can be masked by the overall index, it will be important to present the overall index and the three sub-indices together, not just the overall index. In addition to the aggregate index in biophysical terms, aggregate measures of ecosystem services in monetary terms could be reported by Parties as a component or complementary indicator. If monetary ecosystem services accounts have been developed, aggregate measures in monetary terms can be derived by summing total supply or use for each ecosystem service for the same period, with care taken to use constant prices across accounting periods to ensure that the values are expressed in real rather than nominal terms. The monetary value of ecosystem services can be expressed as a percentage of gross value added (GVA) from the national (economic) accounts.

5c. Data collection method

The compilation of ecosystem services accounts should ideally be based on national time-series datasets for ecosystem services, which could combine data from a range of sources to provide the best available estimates of ecosystem service supply and use. For many ecosystem services, some form of modelling is required to produce these estimates. If suitable national datasets are not available and cannot be developed with current resources, an alternative is to use available global datasets and models to develop initial estimates for the accounts, subject to criteria, standards and quality assurance. Validation by relevant national experts through appropriate institutional processes would be required to assess whether the results from global datasets and models are credible. Several global tools are available, such as ARIES for SEEA, InVEST, ESTIMAP. In some cases, these global tools allow for the incorporation of national datasets and/or models. Further guidance for some ecosystem services is available in Guidelines on Biophysical Modelling for Ecosystem Accounting (United Nations 2021). In addition, a wealth of literature is available on measuring ecosystem services.

Data quality guidelines for this and other headline indicators should be addressed in compilation guidelines.

5d. Accessibility of methodology

The methodology for ecosystem services accounts in biophysical terms is well developed and accepted by the international statistical community as part of the SEEA Ecosystem Accounting framework. 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 services, as an international statistical standard, whereas chapters 8-11, which deal with accounts in monetary terms, were adopted as internationally recognized statistical principles and recommendations for the valuation of ecosystem services.

As noted in Section 5b.2, some material is available to support the development of ecosystem accounts including ecosystem services accounts (for example, SEEA e-learning resources | System of Environmental Economic Accounting), with more in development. In addition, capacity development for Parties, especially for developing countries, should be provided to support the compilation of this this indicator.

As noted in Section 5b.3, further testing is underway to finalise the methodology for developing an aggregate index of trends in ecosystem services that draws on data from ecosystem services accounts.

5e. Data sources

See Section 5c Data collection method. A very wide range of data sources go into the compilation of ecosystem services accounts, and these differ depending on which ecosystem service is being measured. Data could be sourced from research institutions, various government ministries, national mapping agencies, national statistical offices, various government departments and other organs of state at the national or sub-national level (such as municipalities). Remote sensing and earth observation data play an important role for some ecosystem services.

5f. Availability and release calendar

According to the Global Assessment of Environmental-Economic Accounting and Supporting Statistics (2023) undertaken by the UNSD, 22 countries compiled biophysical ecosystem services accounts at least once and 15 countries compiled monetary ecosystem services accounts at least once during the period 2019 to 2023. Ideally ecosystem services accounts would be compiled annually, but in practice few countries would have the capacity to do this, so accounting periods of three to five years are more likely

Global tools and databases to support ecosystem services accounting are currently under development (see Section 5c).

5g. Time series

Data for the indicator in the form of ecosystem services accounts are not yet available for most countries. Time series for different ecosystem services accounts will differ. As ecosystem services accounts are developed at the national level, time series for different ecosystem services will depend on data availability, with back casting possible in some cases.

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.Country baseline dates may be distinct from the global baseline data, depending on data available at the national level.

5h. Data providers

As discussed in Section 5e, a wide range of data sources go into the compilation of ecosystem services accounts. Data providers could include research institutions, various government ministries, national mapping agencies, national statistical offices, various government departments and other organs of state at the national or sub-national level (such as municipalities). Remote sensing and earth observation data play an important role for some ecosystem services.

5i. Data compilers

For countries that have national ecosystem services accounts, the relevant national authorities, in particular the national statistical offices, ministries of environment or related agencies, will compile this indicator. Missing values for individual countries may be estimated using ARIES for SEEA or another international data platform by the custodian agency using existing global data sources, subject to criteria, standards and quality assurance including national validation.

5j. Gaps in data coverage

There are substantial data gaps at this stage for reliable estimates of a suite of ecosystem services in all countries.

5k. Treatment of missing values

Missing values for this indicator could result from several factors, including but not limited to temporal gaps (e.g. once-off datasets, very short time-series or interrupted time series), spatial gaps (e.g. data available only for some sub-regions or local areas within a country), or complete lack of data for some ecosystem services at the national or global level.

As noted in earlier sections, for some ecosystem services, missing values for individual countries may be estimated using ARIES for SEEA or other global modelling platforms based on existing global data, subject to criteria, standards and quality assurance including national validation through appropriate institutional processes involving relevant national experts.

6. Scale

6a. Scale of use

Scale of application: Global, Regional, National

Scale of data disaggregation/aggregation

Global/ regional scale indicator can be disaggregated to national level: Yes

National data is collated to form global indicator: Yes

The indicator is applicable at the global, regional and national scale. National data can be aggregated to global indicators provided that the underlying classifications are harmonized across countries.

6b. National/regional indicator production

6c. Sources of differences between global and national figures

Differences between country-produced and internationally estimated data may arise due to differences in spatial resolution and projections of datasets, classification and modelling approaches, and definitions of particular ecosystem services.

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

6d.1 Description of the methodology

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

6d.2 Additional methodological details

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 for each ecosystem service included in the indicator as well as the overall index and sub-indices. This will provide flexibility in terms of methods for global aggregation. Also see Section 6d.3 below.

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

7. Other MEAs, processes and organisations

7a. Other MEA and processes

7b. Biodiversity Indicator Partnership

No

10. Data reporter

10a. Organisation

United Nations Statistics Division (UNSD)

10b. Contact person(s)

Ilaria Di Matteo (dimatteo@un.org)

Environmental Economic Accounts Section of the UN Statistics Division (seea@un.org)