Page 178 - Invited Paper Session (IPS) - Volume 2

IPS195 Albert B.
Type of Type of LCEU
ecosystem Urban and …
sevices (by Forest tree associated Open
a
CICES) cover Agricultural land developed areas wetlands
Provisioning For example, For example,
services tonnes of
timber tonnes of wheat
Regulating For example, For example, For example, For example,
services tonnes of CO2 tonnes of CO2 tonnes of
stored/released stored/released tonnes of CO2 phosphorus
stored/released
absorbed
Cultural services For example, For example, For example,
number of hectares of hectares of
visitors and habitat for
hikers parkland ducks
a Medium to large fields of rain-fed herbaceous cropland.

However, an aggregation of the different ES-services in physical terms is
complicated due to the different physical measures used. A proposal
mentioned to overcome this difficulty is to use weights for the different ES-
services (like in price statistics) and combine them with the physical measures
transformed to index numbers. This allows compiling growth rates for total
ES-services provided as well as for the basket of ES-services provided by each
land cover type.
3.2 Monetary Data
The advantage of compiling data in monetary unit is that a combination
with other monetary data is enabled, which may be useful for analytical
purposes as well as political discussion. Unfortunately, in practice monetary
values for ES-assets and ES-services are missing in most cases. This requires
looking for substitutes, i.e. imputed or hypothetical prices.
In economics a value usually consists of two elements, a quantity of a
product and the respective market price, i.e. when buyers and sellers are
willing to exchange the product. This exchange value guarantees consistency
between the records of both parties and therefore is a cornerstone of national
accounts. But market prices are not always available, so that in certain cases
alternative valuation methods are accepted as proxy. But there are only few
exceptions to using market prices as valuation basis for products in national
accounts:
- the market prices of similar items is applied for instance in the case of
dwellings used by their owners (based on market rents for comparable
rented dwellings)
- the costs of production are used for government services, which reflect
the market prices for the inputs used, i.e. labor and capital.
Market prices for environmental products can be available sometimes,
particularly when these are used as inputs for production, e.g. mineral
resources. But also, for certain ES-services market prices do exist, for instance

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