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Identification and quantification

In document BKanninen0102 (Page 40-46)

In order to assess the capacity of forests (native or planted) to provide goods and services, indicators are needed. For each of the four categories of goods and services described above (provisioning, regulating, cultural and supporting), the main ecological processes associated with the service provision, and the main indicators determining the capacity of the system to provide the service are listed in Table 2.1. These indicators can be measured in different ways (e.g. literature review, expert consultations, community meetings, field visits or experiments).

One problem with determining sustainable use levels is that many goods and services depend on the same function (i.e. second column in Table 2.1), which means that use of one good or service will influence the availability of another. For example, a continuous supply of timber will depend directly on production functions (biomass production), which, in itself, will depend on habitat functions (i.e. suitable conditions for timber-producing species) and regulating functions (e.g. soil and climate regulation, pollination, etc.). Maintenance of these habitat and regulating functions will contribute, in turn, to the provision of other services (Campos et al, 2005).

In plantations, one service is usually maximized (e.g. timber production) at the expense of most other services and much external input (labour, energy, nutrients) is needed to maintain the productivity. The extent to which this trade-off is acceptable (ecologically, socio-culturally and economically) is the subject of the next section on ‘valuation’.

Valuation

Once the capacity of an ecosystem to provide goods and services is known, their importance or ‘value’ can be determined. This importance or value primarily consists of three types of values: ecological, socio-cultural and economic (MEA, 2005).

Table 2.1 Overview of forest services and examples of indicators for

measuring function performance

Services (comments and examples)

Ecological process and/or component providing the service (or influencing its availability) = Functions

State indicator (how much of the service is present)

Performance indicator (how much can be used /provided in sustainable way)

Provisioning

Food Presence of edible plants and animals

Total or average stock in kg/ha

Actual use in most appropriate unit per ha per year (in relation to maximum sustainable use level) Fibre, fuel and

other raw materials

Presence of species or abiotic components with potential use for timber, fuel or raw material

Total biomass (kg/ha)

Biochemical products and medicinal resources

Presence of species or abiotic components with potentially useful chemicals and/or medicinal use

Total amount of useful substances that can be extracted (kg/ha)

Genetic materials: genes for resistance to plant pathogens

Presence of species with (potentially) useful genetic material

Total ‘gene bank’ value (e.g. number of species and sub- species) Ornamental

species and/or resources

Presence of species or abiotic resources with ornamental use

Total biomass (kg/ha)

Regulating Air quality regulation: e.g. capturing dust particles Capacity of ecosystems to extract aerosols and chemicals from the atmosphere

– Leaf area index – NOx-fixation, etc.

– Amount of pollutants ‘extracted’

– Effect on air quality Climate

regulation

Influence of ecosystems on local and global climate through land- cover and biologically mediated processes – Greenhouse gas balance (esp. C-sequestration) – Land cover characteristics, etc.

Quantity of greenhouse gases etc. fixed and/or emitted ––> effect on climate parameters

Water quality regulation

Role of biota and abiotic processes in removal or breakdown of excess amounts organic matter, nutrients and polluting compounds

– Denitrification (kg N/ha/y)

– Immobilization in plants and soil

Maximum amount of chemicals that can be recycled or immobilized on a sustainable basis

Water regulation Role of forests in water infiltration and gradual release of water

Water retention capacity in soils, etc. or at the surface

Quantity of water retention and influence of hydrological regime (e.g. irrigation)

Table 2.1 continued Services (comments and examples) Ecological process and/or component providing the service (or influencing its availability) = Functions

State indicator (how much of the service is present)

Performance indicator (how much can be used /provided in sustainable way)

Erosion protection

Role of vegetation and biota in soil retention

– Vegetation cover – Root matrix

Amount of soil retained or sediment captured Natural hazard

mitigation

Role of forests in dampening extreme events (e.g. protection against flood damage)

Water-storage (buffer) capacity in m3

Reduction of flood-danger and prevented damage to infrastructure

Biological regulation

Control of pest populations through trophic relations; role of biota in distribution, abundance and effectiveness of pollinators

– Number and impact of pest-control species

– Number and impact of pollinating species

– Reduction of human diseases, live-stock pests, etc

– Dependence of crops on natural pollination

Cultural and Amenity Aesthetic:

appreciation of natural scenery (other than through deliberate recreational activities)

Aesthetic quality of the landscape, based on e.g. structural diversity, ‘greenness’, tranquility

Presence of landscape features with stated appreciation

Expressed aesthetic value, e.g.:

– No. of houses bordering natural areas

– No. of users of ‘scenic routes’ Recreational: opportunities for tourism and recreational activities – Landscape features – Attractive wildlife Presence of landscape and wildlife features with stated recreational value

– Maximum sustainable number of people and facilities

– Actual use Cultural heritage

and identity: sense of place and belonging Culturally important landscape features or species Presence of culturally important landscape features or species

Number of people ‘using’ forests for cultural heritage and identity

Spiritual and artistic inspiration: nature as a source of inspiration for art and religion

Landscape features or species with inspirational value to human arts and religious expressions

Presence of landscape features or species with inspirational value

– No. of people who attach religious significance to forests,

– No. of books, paintings, etc. using ecosystems as inspiration

Ecological valuation

The ‘Ecological Value’, or importance of a given ecosystem, is determined mainly by the degree to which the ecosystem provides Regulation and Habitat Services, which, in turn, is measured by ecosystem criteria such as naturalness, diversity and rarity (see Table 2.2).

Whether plantation forests lead to a decrease in the overall ecological value of an area or landscape depends largely on the condition of the original ecosystem or production system they replaced. For example, ecological values are likely to increase if plantations are established on former agricultural land, and likely to decrease if established on land converted through the clearing of native ecosystems (see also Chapter 5).

Socio-cultural valuation

Social values (such as cultural diversity, identity, heritage and spiritual values) and perceptions play an important role in determining the importance of ecosystems and their services to human society (see Table 2.3). Native forests have many such values and are often an important source of non-material well- being to many individuals and societies.

Usually, socio-cultural values are reduced or lost when a native forest is replaced by a plantation. However, there are large differences depending on the

Table 2.1 continued Services (comments and examples) Ecological process and/or component providing the service (or influencing its availability) = Functions

State indicator (how much of the service is present)

Performance indicator (how much can be used /provided in sustainable way)

Education and science opportunities for formal and informal education and training

Features with special educational and scientific value/interest Presence of features with special educational and scientific value/interest

Number of classes visiting Number of scientific studies etc Supporting Habitat and nursery service Importance of ecosystems to provide breeding, feeding or resting habitat to resident or migratory species (and thus maintain a certain ecological balance and evolutionary processes) – No. of resident, endemic species – No. of transient species – Habitat integrity – Minimum critical surface area of specific habitat

– ‘Ecological Value’ (i.e. difference between actual and potential biodiversity value)

– Dependence of transient species on specific area

management system, and so-called ‘community forests’ (which are usually more or less heavily managed native forests), can have considerable socio- cultural importance.

To some extent these values can be captured by economic valuation methods (see further below), but these techniques do not capture fully the extent to which some ecosystem services are essential to people’s very identity and existence.

Economic valuation

Finally, ecosystem services have economic importance, although some authors regard cultural values and their social welfare indicators as a sub-set of economic values. Others state that, in practice, economic valuation is limited to efficiency and cost-effectiveness analyses, usually measured in monetary units, and disregards the importance of, for example, spiritual values and cultural identity.

Therefore, in this chapter, economic and monetary valuation are treated separately from socio-cultural valuation. However, it is emphasized that ecological, socio-cultural and economic values all have their separate role in decision-making and should be seen as essentially complementary pieces of information in the decision-making process.

To analyse the economic value of ecosystems, the concept of Total Economic Value (TEV) (Figure 2.1) has become a framework widely used for quantifying the utilitarian value of ecosystems (de Groot et al, 2006). This framework typically disaggregates TEV into two categories: use values and

non-use values.

Table 2.2 Ecological valuation criteria and measurement indicators

Criteria Short description Measurement units/indicators

Naturalness/Integrity Degree of human presence in – Quality of air, water and soil (representativeness) terms of physical, chemical or – % key species present

biological disturbance. – % of min. critical ecosystem size Diversity Variety of life in all its forms, – number of ecosystems per

including ecosystems, species geographical unit

and genetic diversity. – number of species/surface area Uniqueness/rarity Local, national or global rarity – number of endemic species and

of ecosystems and species sub-species

Fragility/vulnerability Sensitivity of ecosystems to – energy budget (GPP/NPP) 1

(resistance) human disturbance – carrying capacity Resilience The possibility of spontaneous – complexity and diversity Renewability/ renewal or human aided – succession stage/time restorability restoration of ecosystems

1GPP – Gross Primary Production; NPP = Net Primary Production

Use values comprise three elements: direct use, indirect use and option

values. Direct use value is also known as the extractive, consumptive or structural use value and derives mainly from goods that can be extracted, consumed or enjoyed directly (Dixon and Pagiola, 1998). Indirect use value is also known as the non-extractive use value, or functional value and derives mainly from the services the environment provides (Dixon and Pagiola, 1998).

Option value is the value attached to maintaining the option to take advantage

of the use value of something at a later date. Some authors also distinguish

quasi option value, which derives from the possibility that even though

something appears unimportant now, information received later might lead us to re-evaluate it (Dixon and Pagiola, 1998).

Non-use values, as the name says, derives from benefits the environment

may provide when it is not used in any way. In many cases, the most important benefit of this kind is existence value; the value people derive from the knowledge that something exists even if they never plan to use it. Thus people place a value on the existence of blue whales or the panda even though they have never seen one and probably never will. However, if blue whales became

Table 2.3 Socio-cultural valuation criteria and measurement indicators

Criteria Short description Measurement units/indicators

Therapeutic value The provision of clean air, water – Suitability and capacity of natural and soil, space for recreation and systems to provide ‘health services’ outdoor sports and general – Restorative and regenerative effects on therapeutic effects of nature on peoples’ performance

people’s mental and physical – Socio-economic benefits from reduced well-being health costs and conditions

Amenity value Importance of nature for cognitive – Aesthetic quality of landscapes development, mental relaxation – Recreational features and use artistic inspiration, aesthetic – Artistic features and use enjoyment and recreational – Preference studies benefits

Heritage value Importance of nature as reference – Historic sites, features and artefacts to personal or collective history – Designated cultural landscapes and cultural identity – Cultural traditions and knowledge Spiritual value Importance of nature in symbols – Presence of sacred sites or features

and elements with sacred, religious – Role of ecosystems and/or species in and spiritual significance religious ceremonies and sacred texts Existence value Importance people attach to nature – Expressed (through, for example,

for ethical reasons (intrinsic value) donations and voluntary work) or and inter-generational equity stated preference for nature protection (bequest value). Also referred to as for ethical reasons

‘warm glow-value’

extinct, many people would feel a definite sense of loss (Dixon and Pagiola, 1998). Bequest value is the value derived from the desire to pass on values to future generations (i.e. our children and grandchildren).

In document BKanninen0102 (Page 40-46)