Exchange values are the values at which goods, services, labour or assets are in fact exchanged or else could be exchanged for cash

Source/reference: SEEA-EA 2021, para. 8.13.
Note: Exchange values are usually based on observed market prices. Where there is no observable market for a good or service, then exchange values may be estimated based on market prices for similar or analogous items, adjusted if necessary for quality and other differences; or based on what it costs currently to produce the good or service. Assets may be priced at market prices, or the written down replacement cost (current price of an equivalent new asset less accumulated depreciation), or the discounted present value of future returns (SEEA-EA, para. 8.20). As the first two of these options are not generally applicable to ecosystem assets, they are valued using a net present value approach. In other words, first the economic contribution of the ecosystem asset to each ecosystem service that it provides must be estimated (as per the monetary flows tabs for each ecosystem service), then these values for each year into the future should be discounted using an appropriate discount rate, and the discounted values for all years and all ecosystem services added together to arrive at the discounted present value of the ecosystem asset. For further guidance on monetary valuation see NCAVES and MAIA (2022).

Environmental assets are the naturally occurring living and non-living components of the Earth, together constituting the biophysical environment, which may provide benefits to humanity. …In the Central Framework, the focus is on individual components of the environment that provide materials and space to all economic activities. Examples include mineral and energy resources, timber resources, water resources and land.

Source/reference: SEEA-CF 2014, para. 2.17.
Note: “The term “land” as applied in the SEEA also encompasses areas of inland water such as rivers and lakes.” (SEEA-CF 2014, para. 5.21)

ecosystem services are the contributions of ecosystems to the benefits that are used in economic and other human activity

Source/reference: SEEA-EA 2021, para. 6.9.
Note: See SEEA-EA 2021, Table 6.3 for reference list of selected ecosystem services.

the size of an ecosystem asset in terms of spatial area.

Source/reference: SEEA-EA 2021, para. 2.13.

…the condition of an ecosystem asset is interpreted as the ensemble of multiple relevant ecosystem characteristics, which are measured by sets of variables and indicators that in turn are used to compile the accounts. Variables and indicators are selected in relation to the context and purpose of assessment, and different considerations will be relevant across natural and anthropogenic ecosystems. Individual indicators can be aggregated to composite indices that provide a synthesis of the integrity, health or naturalness of an ecosystem asset.

Source/reference: SEEA-EA 2021, para. 5.18.

Ecosystem condition variables are quantitative metrics describing individual characteristics of an ecosystem asset. A single characteristic can have several associated variables, which may be complementary or overlapping. Variables differ from characteristics (even if the same descriptor is applied to them) as they have a clear and unambiguous definition (measurement instructions, formulae, etc.) and well-defined measurement units that indicate the quantity or quality they measure.

Source/reference: SEEA-EA 2021, para. 5.41.
Note: Examples of ecosystem condition variables for selected ecosystem types are given in SEEA-EA 2021, Table 5.7.

For a full list of SEEA ECT groups and classes, please see Table 5.1 in SEEA-EA 2021.

Source/reference: SEEA-EA 2021, Table 5.1.

Ecosystem condition indices and sub-indices are composite indicators that are aggregated from the combination of individual ecosystem condition indicators recorded in the ecosystem condition indicator account

Source/reference: SEEA-EA 2021, para. 5.81.

Ecosystem condition indicators are rescaled versions of ecosystem condition variables. They are derived when condition variables are set against reference levels determined with respect to ecological integrity.

Source/reference: SEEA-EA 2021, para. 5.60.

Ecosystem condition is the quality of an ecosystem measured in terms of its abiotic and biotic characteristics. Condition is assessed with respect to an ecosystem’s composition, structure and function which, in turn, underpin the ecological integrity of the ecosystem, and support its capacity to supply ecosystem services on an ongoing basis. Measures of ecosystem condition may reflect multiple values and may be undertaken across a range of temporal and spatial scales.

Source/reference: SEEA-EA 2021, para. 5.2.