The categorisation of ecosystem services varies depending on classification system. The
Millennium Ecosystem Assessment (MA) groups the services into the four groups: regulating services, provisioning services, cultural services and supporting services, where the so-called supporting services are regarded as the basis for the services of the other three categories. An ecosystem does not necessarily offer all four types of services simultaneously; but given the intricate nature of any ecosystem, it is usually assumed that humans benefit from a combination of these services . The services offered by diverse types of ecosystems (forests, seas, coral reefs, mangroves, etc.) differ in nature and in consequence. In fact, some services directly affect the livelihood of neighboring human populations (such as fresh water, food or aesthetic value, etc.) while other services affect general environmental conditions by which humans are indirectly impacted (such as
climate change,
erosion regulation or
natural hazard regulation, etc.). By 2010, there had evolved various working definitions and descriptions of ecosystem services in the literature. To prevent double-counting in ecosystem services audits, for instance,
The Economics of Ecosystems and Biodiversity replaced
Supporting Services in the MA with
Habitat Services, and "ecosystem functions", defined as "a subset of the interactions between ecosystem structure and processes that underpin the capacity of an ecosystem to provide goods and services". This was further developed by the Common International Classification for Ecosystem Services, which uses the categories of
Cultural and
Provisioning, but combines
Regulatory and
Habitat services into the category
Regulation and maintenance services.
Provisioning services Provisioning services consist of all "the products obtained from ecosystems". The following services are also known as
ecosystem goods: • food (including
seafood and
game), crops, wild foods, and
spices • raw materials (including lumber, skins, fuelwood, organic matter, fodder, and fertilizer) • genetic resources (including crop improvement genes, and health care) •
biogenic minerals •
medicinal resources (including pharmaceuticals, chemical models, and test and assay organisms) •
energy (
hydropower,
biomass fuels) • ornamental resources (including fashion, handicrafts, jewelry, pets, worship, decoration, and souvenirs like furs, feathers, ivory, orchids, butterflies, aquarium fish, shells, etc.)
Products from forests in Andhra Pradesh,
India, providing fuel, soil protection, shade, and even well-being to travelers.Forests and
forest management produce a large type and variety of timber products, including roundwood, sawnwood, panels, and engineered wood, e.g., cross-laminated timber, as well as pulp and paper. Besides the production of timber, forestry activities may also result in products that undergo little processing, such as fire wood, charcoal, wood chips and roundwood used in an unprocessed form. Global production and trade of all major wood-based products recorded their highest ever values in 2018. Production, imports and exports of roundwood, sawnwood, wood-based panels, wood pulp, wood charcoal and pellets reached their maximum quantities since 1947 when
FAO started reporting global forest product statistics. Forests also provide non-wood forest products, including fodder, aromatic and medicinal plants, and wild foods. Worldwide, around 1 billion people depend to some extent on wild foods such as wild meat, edible insects, edible plant products, mushrooms and fish, which often contain high levels of key micronutrients. These include: • Purification of
water and
air •
Carbon sequestration (this contributes to
climate change mitigation) • Waste
decomposition and detoxification •
Predation regulates prey populations • Biological control
pest and
disease control •
Pollination • Disturbance regulation, i.e. flood protection
Water purification An example for water purification as an ecosystem service is as follows: In
New York City, where the quality of drinking water had fallen below standards required by the
U.S. Environmental Protection Agency (EPA), authorities opted to restore the polluted
Catskill Watershed that had previously provided the city with the ecosystem service of water purification. Once the input of sewage and pesticides to the
watershed area was reduced, natural
abiotic processes such as soil
absorption and
filtration of chemicals, together with biotic recycling via root systems and soil
microorganisms,
water quality improved to levels that met government standards. The cost of this investment in
natural capital was estimated at $1–1.5 billion, which contrasted dramatically with the estimated $6–8 billion cost of constructing a
water filtration plant plus the $300 million annual running costs.
Pollination Pollination of
crops by bees is required for 15–30% of U.S.
food production; most large-scale farmers import non-native honey bees to provide this service. A 2005 study reported that in California's agricultural region, it was found that wild bees alone could provide partial or complete pollination services or enhance the services provided by honey bees through behavioral interactions. However,
intensified agricultural practices can quickly erode pollination services through the loss of species. The remaining species are unable to compensate this. The results of this study also indicate that the proportion of
chaparral and
oak-woodland habitat available for wild bees within 1–2 km of a
farm can stabilize and enhance the provision of pollination services. The presence of such ecosystem elements functions almost like an insurance policy for farmers. Another way to increase pollination services is to increase the amount of native flowering plants available for wild bees can forage on. This can be done by planting specific flowers in urban areas nearby, or even on the farm itself.
Buffer zones Coastal and estuarine ecosystems act as buffer zones against natural hazards and environmental disturbances, such as floods, cyclones, tidal surges and storms. The role they play is to "[absorb] a portion of the impact and thus [lessen] its effect on the land".
Wetlands (which include
saltwater swamps,
salt marshes, ...) and the vegetation it supports – trees, root mats, etc. – retain large amounts of water (surface water, snowmelt, rain, groundwater) and then slowly releases them back, decreasing the likeliness of floods.
Mangrove forests protect coastal shorelines from tidal erosion or erosion by currents; a process that was studied after the 1999 cyclone that hit India. Villages that were surrounded with mangrove forests encountered less damages than other villages that were not protected by mangroves.
Supporting services Supporting services are the services that allow for the other ecosystem services to be present. They have indirect impacts on humans that last over a long period of time. Several services can be considered as being both supporting services and regulating/cultural/provisioning services. Supporting services include for example
nutrient cycling,
primary production,
soil formation,
habitat provision. These services make it possible for the ecosystems to continue providing services such as food supply, flood regulation, and water purification.
Nutrient cycling s like this
dung beetle help to turn animal wastes into organic material that can be reused by primary producers. Nutrient cycling is the movement of nutrients through an ecosystem by biotic and abiotic processes. The ocean is a vast storage pool for these nutrients, such as carbon, nitrogen and phosphorus. The nutrients are absorbed by the basic organisms of the marine food web and are thus transferred from one organism to the other and from one ecosystem to the other. Nutrients are recycled through the life cycle of organisms as they die and decompose, releasing the nutrients into the neighboring environment. "The service of nutrient cycling eventually impacts all other ecosystem services as all living things require a constant supply of nutrients to survive". On average, a human consumes about 550 liter of oxygen per day, whereas plants produce 1,5 liter of oxygen per 10 grams of growth.
Cultural services Cultural services relate to the non-material world, as they benefit recreational, aesthetic, cognitive and spiritual activities, which are not easily quantifiable in monetary terms. They include: • cultural (including use of nature as motif in books, film, painting, folklore, national symbols, advertising, etc.) • spiritual and historical (including use of nature for religious or heritage value or natural) •
recreational experiences (including
ecotourism, outdoor sports, and recreation) • science and education (including use of natural systems for school excursions, and
scientific discovery) • therapeutic (including eco-therapy, social forestry and animal assisted therapy) As of 2012, there was a discussion as to how the concept of cultural ecosystem services could be operationalized, how landscape aesthetics, cultural heritage, outdoor recreation, and spiritual significance to define can fit into the ecosystem services approach. who vote for models that explicitly link ecological structures and functions with cultural values and benefits. Likewise, there has been a fundamental critique of the concept of cultural ecosystem services that builds on three arguments: • Pivotal cultural values attaching to the natural/cultivated environment rely on an area's unique character that cannot be addressed by methods that use universal scientific parameters to determine ecological structures and functions. • If a natural/cultivated environment has symbolic meanings and cultural values the object of these values are not ecosystems but shaped phenomena like mountains, lakes, forests, and, mainly, symbolic landscapes. • Cultural values do result not from properties produced by ecosystems but are the product of a specific way of seeing within the given cultural framework of symbolic experience. The Common International Classification of Ecosystem Services is a classification scheme developed to accounting systems (like National counts etc.), in order to avoid double-counting of Supporting Services with others Provisioning and Regulating Services.
Recreation and tourism Sea sports are very popular among coastal populations: surfing, snorkeling, whale watching, kayaking, recreational fishing ... a lot of tourists also travel to resorts close to the sea or rivers or lakes to be able to experience these activities, and relax near the water. The United Nations
Sustainable Development Goal 14 also has targets aimed at enhancing the use of ecosystem services for sustainable tourism especially in
Small Island Developing States. ==Estuarine and coastal ecosystem services==