Ecosystem services are the different benefits that people get from ecosystems. The connected living and non-living parts of nature provide advantages like pollinating crops, keeping air and water clean, breaking down waste, and controlling floods. These services are important for human health. They offer both direct and indirect help from nature, such as clean water, food, and managing the climate.

Scientists group ecosystem services into categories, a method introduced in the early 2000s by the Millennium Ecosystem Assessment (MA) project led by the United Nations. How these groups are defined depends on the classification system used. The MA divides services into four main types: provisioning services, such as producing food and water; regulating services, such as controlling climate and disease; supporting services, such as nutrient cycles and oxygen production; and cultural services, such as recreation, tourism, and spiritual fulfillment.

For example, estuarine and coastal ecosystems are marine environments that provide all four types of ecosystem services. First, their provisioning services include resources like seafood and genetic material. Second, their supporting services involve nutrient recycling and creating food for other organisms. Third, their regulating services help reduce carbon in the atmosphere (which helps control climate change) and prevent flooding. Finally, their cultural services include activities like tourism and recreation. Sometimes, ecosystem services are studied by giving them a monetary value.

Definition

Ecosystem services are the goods and services that ecosystems provide to humans. According to the 2006 Millennium Ecosystem Assessment (MA), ecosystem services are "the benefits people obtain from ecosystems."

Gretchen Daily's original definition separated ecosystem goods from ecosystem services. However, later work by Robert Costanza and his team, along with the MA, combined both goods and services into one category called ecosystem services.

Categories

The way ecosystem services are grouped depends on the classification system used. The Millennium Ecosystem Assessment (MA) divides ecosystem services into four categories: regulating services, provisioning services, cultural services, and supporting services. Supporting services are considered the foundation for the other three types.

An ecosystem may not provide all four types of services at the same time. However, because ecosystems are complex, it is common for humans to benefit from a mix of these services. Different ecosystems, such as forests, oceans, coral reefs, and mangroves, offer services that vary in type and effect. Some services directly help people, like providing clean water, food, or beauty. Others indirectly affect humans by influencing environmental conditions, such as controlling climate change, reducing erosion, or managing natural disasters.

By 2010, many definitions of ecosystem services had been developed. To avoid counting the same service twice, the Economics of Ecosystems and Biodiversity program changed the term "Supporting Services" from the MA to "Habitat Services." It also introduced the term "ecosystem functions," which refers to the interactions within an ecosystem that help it provide goods and services. The Common International Classification for Ecosystem Services later grouped Regulatory and Habitat Services into a single category called "Regulation and Maintenance Services."

Provisioning services are the products people get from ecosystems. These include:
– Food (such as seafood, crops, wild plants, and spices)
– Raw materials (like wood, fuel, and fertilizer)
– Genetic resources (such as genes for improving crops or medicine)
– Minerals from living things
– Medicines (including drugs and test organisms)
– Energy (such as hydropower and biomass)
– Ornamental items (like jewelry, pets, and souvenirs)

Forests and their management produce many wood products, such as timber, paper, and engineered wood. Other products include firewood, charcoal, and unprocessed wood. In 2018, the production and trade of wood-based products reached record levels. The fastest growth in production occurred in the Asia-Pacific, North America, and Europe, likely due to strong economic growth in these regions. Over 40% of the European Union’s land is covered by forests, which have grown slightly through tree planting. However, only 60% of the wood produced in the EU each year is used.

Forests also provide non-wood products, such as animal feed, medicinal plants, and wild foods. Around 1 billion people rely on wild foods like meat, insects, and mushrooms, which are rich in nutrients. In the EU, over 100 million people eat wild foods regularly. More than 2.4 billion people use wood-based energy for cooking.

Regulating services are the benefits people get from how ecosystems manage natural processes. These include:
– Cleaning water and air
– Storing carbon to help reduce climate change
– Breaking down waste and toxins
– Controlling animal populations through predation
– Managing pests and diseases
– Pollinating plants
– Reducing the impact of floods and storms

For example, New York City restored the Catskill Watershed to improve drinking water quality. After reducing pollution, natural processes like soil filtering and microbial activity improved water quality. This natural solution cost about $1–1.5 billion, which was much less than building a water filtration plant, which would have cost $6–8 billion plus $300 million yearly in operating costs.

Pollination by bees is vital for 15–30% of U.S. food production. Many farmers bring in non-native bees to help pollinate crops. A study in California found that wild bees could pollinate crops or help honey bees work more effectively. However, farming practices that harm wildlife can reduce pollination services. Leaving areas with shrubs and oak trees near farms can help wild bees and improve pollination. Planting native flowers in cities or on farms can also support pollination.

Coastal and estuarine ecosystems protect against natural disasters like floods and storms. Wetlands and mangroves absorb water and reduce flood damage. For example, after a 1999 cyclone in India, villages with mangroves suffered less damage than those without.

Supporting services are the services that enable other ecosystem services to exist. They have long-term effects on humans but are not always directly visible. Examples include nutrient cycling, soil formation, and providing habitats. These services help ecosystems continue to provide other services like food, clean water, and climate regulation. Some services can be both supporting and regulating, cultural, or provisioning services.

Estuarine and coastal ecosystem services

Estuarine and marine coastal ecosystems are types of marine ecosystems. These ecosystems provide four types of services in different ways: Provisioning services include resources such as forest products, marine life, fresh water, raw materials, biochemical substances, and genetic material. Regulating services involve processes like absorbing carbon (which helps reduce climate change), treating waste, controlling diseases, and creating natural barriers. Supporting services include recycling nutrients, forming habitats through biological processes, and producing energy through plant growth. Cultural services involve inspiring people, offering opportunities for recreation and tourism, and supporting science and education.

Coasts and the areas near them, both on land and in the ocean, are important parts of local ecosystems. The mix of fresh water and salt water (brackish water) in estuaries provides nutrients for marine life. Salt marshes, mangroves, and beaches support a wide variety of plants, animals, and insects that are important for the food chain. The high level of biodiversity leads to high biological activity, which has drawn human activity for thousands of years. Coasts also provide essential living conditions for organisms, such as estuaries, wetlands, seagrass beds, coral reefs, and mangroves. These areas are habitats for migratory birds, sea turtles, marine mammals, and coral reefs.

Economics

There are questions about the environmental and economic value of ecosystem services. Some people may not fully understand the environment or how humans are connected to it, which can lead to misunderstandings. Although awareness of the environment is growing, many people still do not understand how ecosystem services work or the threats they face. This can lead to problems, such as the "tragedy of the commons," where shared resources are overused. Efforts are being made to help decision-makers understand the costs and benefits of choices by translating scientific information into economic terms. This helps compare the effects of decisions on human well-being. A challenge is that information about ecosystems collected in one place or time may not apply to another place or time. Understanding how ecosystems function is important for making economic decisions. Factors like how replaceable a service is or how services are grouped together can help assign economic value more effectively.

Valuing ecosystem services also involves communication and sharing information, which is difficult and studied by many researchers. In general, people make choices for different reasons, but patterns in their choices can show what a society values overall. This helps assign economic value to ecosystem services. Six main methods are used to assign monetary value to ecosystem services:

• Avoided cost: Services help society avoid costs that would happen without them (e.g., wetlands reduce health costs by treating waste).
• Replacement cost: Services can be replaced by human-made systems (e.g., restoring the Catskill Watershed cost less than building a water purification plant).
• Factor income: Services improve incomes (e.g., better water quality increases fishery profits and fishers' income).
• Travel cost: The cost of traveling to use a service can show its value (e.g., ecotourism value is at least what visitors pay to visit).
• Hedonic pricing: Prices people pay for goods linked to services can reflect their value (e.g., coastal homes cost more than inland homes).
• Contingent valuation: Hypothetical scenarios can show how much people value services (e.g., visitors may pay for better access to national parks).

A study from 1997 estimated the value of global ecosystem services and natural capital to be between $16 and $54 trillion per year, with an average of $33 trillion per year. However, Salles (2011) stated, "The total value of biodiversity is infinite, so debating its total value is pointless because we cannot live without it."

By 2012, many companies did not fully understand how much they relied on ecosystems or the effects of their actions. Environmental management tools are better at handling traditional issues like pollution, not dependence on ecosystems. Some tools help businesses value ecosystem services, including Our Ecosystem, the 2008 Corporate Ecosystem Services Review, the Artificial Intelligence for Environment & Sustainability (ARIES) project from 2007, the Natural Value Initiative (2012), and InVEST (2012).

For example, the U.S. Department of Defense's land provides ecosystem services like carbon storage and habitat for endangered species. As of 2020, Eglin Air Force Base was estimated to provide about $110 million in ecosystem services annually, $40 million more than if the base did not exist.

Payments for ecosystem services (PES), also called payments for environmental services, are incentives given to farmers or landowners for managing land to provide ecological benefits. These programs are defined as "a transparent system for offering environmental services through payments to those who voluntarily provide them." They encourage conservation in the marketplace.

Management and policy

Although money is still used to value ecosystem services, challenges in creating and managing policies are large and difficult. Managing shared natural resources has been studied a lot by experts. Finding solutions that work in real life and are sustainable is hard. Decisions must balance needs now and in the future, but often rely on information that is not complete. Current laws are often seen as not enough because they focus on human health instead of protecting ecosystems. In 2000, an idea called the Ecosystem Services Framework (ESF) was suggested. This framework combines information about nature and the economy to help institutions make better decisions.

By 2005, local and regional groups were working together to manage services like pollination and resources like water. In the 1990s, a new method became popular: selling credits for protecting ecosystem services. For example, people can earn credits by helping protect forests or restore wetlands. Some companies now sell these credits, and some even trade them on stock markets. However, clear land ownership rules are needed for these efforts to work, especially in developing countries. Many countries with forests face conflicts between groups that use the land. Also, global efforts to buy and sell ecosystem services sometimes lead to unfair payments or misuse of resources. By 2001, another idea focused on protecting areas with high biodiversity, like hotspots. This approach connects protecting ecosystems with traditional conservation goals, such as saving plants and animals. It may help by linking different areas and getting more people to invest in protecting services.

In 2013, scientists studied the value of ecosystem services from shellfish like oysters. These shellfish are important in the food chain and support many other species. They help clean water and reduce pollution by removing excess nutrients. By 2018, the idea of ecosystem services had not yet been fully included in international laws.

Despite this, the United Nations has a goal to protect and use ecosystem services wisely. Ecosystem services are estimated to add about $125 trillion to $140 trillion to the global economy each year. However, these services are at risk because of climate change and human activities. Scientists predict that by 2100, climate changes could reduce ecosystem services by about 9% globally.

Ecosystem-based adaptation (EbA) includes ways to use nature to help people deal with climate change. This involves protecting, managing, and restoring ecosystems like forests, wetlands, and coral reefs. These efforts can reduce risks from climate problems, such as extreme weather or changing rainfall patterns. EbA can be used alone or with other methods, like building dams or using early warning systems.

Decisions about ecosystem services require balancing many factors, including science, technology, society, and the economy. These choices must consider different viewpoints from groups like government agencies, scientists, and local communities. They often involve uncertain data and require combining the best scientific information with people’s opinions.

Some studies have used models to help with decisions. One study looked at water management in New Mexico but did not account for uncertainty. Another used math methods to study how land use changes affect decisions. A third used a system to handle uncertainty in scientific data and include people’s opinions when choosing where to place wave energy devices off Oregon. Remote sensing tools can also help track the health of ecosystems and guide planning.

In the Baltic countries, scientists, conservationists, and local governments are using a planning tool based on maps and computer systems to manage grasslands. This tool helps planners choose the best ways to manage grasslands by considering both natural and human factors.

History

The idea that humans rely on Earth's ecosystems began when humans first appeared. The term "natural capital" was first used by E. F. Schumacher in 1973 in his book Small is Beautiful. Earlier, around 400 BC, the philosopher Plato recognized that cutting down forests could cause soil erosion and dry up water sources. In 1864, George Perkins Marsh challenged the belief that Earth's natural resources were endless by showing how soil fertility changed in the Mediterranean. It was not until the late 1940s that three authors—Henry Fairfield Osborn, Jr., William Vogt, and Aldo Leopold—helped people understand the importance of depending on the environment.

In 1956, Paul Sears highlighted the role of ecosystems in breaking down waste and recycling nutrients. In 1970, Paul Ehrlich and Rosa Weigert discussed "ecological systems" in their textbook, warning that human activities could destroy the systems humans depend on for survival.

The term "environmental services" appeared in a 1970 report that listed services such as insect pollination, fishing, climate control, and flood prevention. Over time, variations of this term were used, but "ecosystem services" became the standard in scientific writing.

In the 1990s, two important books were published: Nature's Service by Gretchen Daily, which influenced discussions about ecosystem services, and The Value of the World's Ecosystem Services and Natural Capital by Costanza et al., which was the first study to assign an economic value to ecosystem services.

The concept of ecosystem services has grown to include goals related to society, the economy, and protecting nature.