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The Value of Ecosystems

Bees pollinating the flowers in a garden. Clean water flowing into your sink. A hiking trail that leads to a mountain vista unobstructed by development and untainted by smog. A snorkeling site resplendent with hundreds of colorful fish. If asked what these ecosystem goods and services are worth, many people would simply say, "they're priceless."

But sometimes we need to be more specific about what ecosystems are worth, even if trying to put a price tag on them seems ridiculous, or ammoral, or yields less-than-perfect results. Why?

Consider how, every day, we assign economic values to our work and our labor, and we use those values to make decisions about our assets — what to buy and what to save, for example. Similarly, the values we assign to ecosystem assets — goods and services like pollination or water filtration — are an important factor in how we treat ecosystems. Yet because these goods and services are not routinely bought and sold in markets, there's no easy way to calculate their worth. Too often, decisionmakers and traditional economists simply ignore their value, essentially treating ecosystem goods and services as if they will always be in profuse supply. The result is that loggers may harvest a patch of forest for the value of its timber alone, ignoring the value that the forest provides in terms of flood control, water purification, or habitat for migratory songbirds.

How does one assign value to all the elements of an ecosystem? Economists have identified a variety of tools to quantify direct — and even some indirect and intangible — ecosystem services.

Where possible, actual market values are used. For example, in the United States, we might estimate that pollinators are worth at least $20-$40 billion — the value of the crops that wouldn't exist without the help of pollinators. Another way to estimate value is to calculate the cost of replacing an ecosystem service. For New York City, natural habitats in its upstate watershed were shown to provide the same water purification services as a new water filtration plant. The $3-$8 billion price tag for the proposed filtration plant is a good base estimate of the value of the water purification service that the intact ecosystem provides — although it does not capture the value of other watershed services like carbon sequestration, recreational opportunities, and support for biodiversity.

Herdsman
Herdsman in Mongolia
Market-based methods of calculating value can also be applied to a lake or a park; to determine its value as a scenic and a recreational site, economists might calculate how much money and time visitors spend to travel there. When market data is not available, researchers resort to other means to assess the value of an ecosystem. They ask people what they'd pay, for example, to keep a wetland from being filled or to prevent a wilderness area from being mined. Properly done, such surveys can measure the value of an ecosystem in terms of the practical benefits that it provides, as well as the spiritual and ethical values people may attach to it.

In some ways, "priceless" may be the most accurate value that we can ever place on a coastal areas's beauty, or a mountain range's spirtual importance. But used as one of many measure of an ecosystem's worth, and with recognition of its limitations, ecosystem valuation can be a powerful management tool in a political world. Until we fully understand what ecosystems are worth, we are handicapped in deciding what to use and what to save.

"Everything that we use comes from nature. Nature is important for our livestock, and it's important for our lifestyle as well."

— Naisurendorj, Livestock Herder, Mongolian Steppe

Many of us rarely consider what ecosystems are worth. We're losing our link with nature: we work in offices, we don't grow our own food, we may live in cities in which natural ecosystems seem remote. A Mongolian herder likeNaisurendorg or a farmer like Charlie Melander know that their wealth and welfare are determined by ecosystem goods and services like soil fertility, biodiversity, the effects of climate change, or the degree to which grasslands or agroecosystems can inexpensively supply food, fodder, or clean water. The rest of us are reminded of the value of the ecosystems most often when they are harmed or destroyed. Perhaps some coastal areas are overfished, and our favorite seafood is no longer available in the market or its price increases. Perhaps a nearby field or forest is turned into a housing development, and we reflect for the first time on the "value" the open space once offered us.

Initially, the Canadian Indians, environmental activists, and the lumber company MacMillan Bloedel clashed because they valued the trees in Clayoquot Sound for different reasons. MacMillan Bloedel focused on the trees' value as timber, which is part of a $15 billion industry in Canada. The Indians valued the trees for the jobs that removing them would provide, and for spiritual and cultural reasons. The environmentalists valued the trees as an integral part of the forest's biodiversity, carbon storage and water filtration capacities, and wildlife habitat.

Fortunately, the parties found a way to capture everyone's values, and in the process to help protect the forest's longterm benefits for all. The solution is to harvest the forest in Clayquot Sound sustainably by logging selectively and flying trees out instead of cutting new roads, thereby saving wildlife habitat, and preserving biodiversity, water quality, and the climate. They added the value of these new services into the price of the finished lumber so that consumers who value the forest's full complement of goods and services may pay more for wood from Clayquot Sound, but they know that the wood is "certified" and was harvested sustainably.

Prices in the marketplace frequently send the wrong signals. In most cases, they don't reflect the real costs to the environment of harvesting an ecosystem good or using an ecosystem service. The problem is, many of the less tangible aspects of ecosystems — particularly the services they provide like recreation, spiritual enjoyment, or carbon storage — are not bought or sold in the marketplace, and are therefore harder to value.

Think about entrance fees to a US National Park: $20 a week for a carload of people to spend a week in the Grand Canyon, Yellowstone, or Yosemite is less than the cost of dinner at McDonald's for a family of four, and probably fails to capture the true value that those visitors place on the recreational opportunities the park provides. Certainly the entrance fee doesn't take
Clearcut Valley
The effects of clearcutting in Canada.
into account the costs those visitors incur — from wear on hiking trails, to water used during their visit, to carbon dioxide emitted from their car as they drive about.

For example, capturing or using one item of value that an ecosystem like a forest provides — say, gold ore — can decrease the forest's value in other ways, like its value as a source of biodiversity. That's a tradeoff that needs to be assessed before deciding whether to mine and how to mine. This mine, for example, is providing gold ore — worth a great deal to a company. But the roads which help the company remove the gold and the losses of the trees from digging the mine and gaining access to it decrease and fragment wildlife habitat. If pollution occurs, the value of the water that flows from this area could be destroyed. Or, the mine site and roads may reduce the value of the forest to some people as a place to hike, camp, or hunt.

"In Brazil, people like to go to the beach, play beach sports, be there for Carnival. There are a lot of traditional rituals…and a cultural relationship with the sea and with the seaside."

— Beatrice Ferreira, Marine Biologist, Recife, Brazil

Placing a value on an ecosystem's beauty or its cultural importance is far more difficult than valuing the direct goods provided by an ecosystem, like the value of fish as a food source, for example. But the reef also holds value for the local citizens as a place for fun and relaxation and as a lure for tourists visiting from the United States and elsewhere.

Gathering Clams
Gathering clams in Brazil.
It is more difficult to put a price on these other values, however, and even when we can, we must reconcile differing priorities when it comes to these values. For some, it is the essential goods that ecosystems provide for human welfare, like food and fiber, that mean the most. Others may find their greatest joy is the restful, calming and revitalizing aspects that the others find perplexing. For others still, they believe that God created the natural world, and therefore it's wrong to abuse it — a concept difficult to translate into a monetary amount. Some people place a high value on an ecosystem's "existence value" — they gain pleasure simply from knowing an ecosystem and its species and services exist, even if it is a remote place like the Artic National Wildlife Refuge, or Mount Kilimanjaro, that they'll probably never visit.

Agricultural | Forests | Coastal | Grasslands | Freshwater | Urban
The Value of Ecosystems


 
 
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