Multiple Values

It is never quite as simple as in the textbooks. Here in Cuba, mangroves, seagrasses and corals grow in close proximity, forming an interconnected ecosystem. In this photo, a juvenile snapper shelters among them. Photo Credit: Mark Spalding

It is never quite as simple as in the textbooks. Here in Cuba, mangroves, seagrasses and corals grow in close proximity, forming an interconnected ecosystem. In this photo, a juvenile snapper shelters among them. Photo Credit: Mark Spalding

Much of our early work into modelling ecosystem services has focused on improving our understanding of the value of single services coming out of individual ecosystems. The real world is more complex, however, with many ecosystems in close proximity, each generating multiple benefits, but also interacting with each other, both ecologically and in terms of the social and economic benefits.

Combined Services, Combined Habitats

At the level of individual habitats, the overlay of services is conceptually simple. For example, a coral reef may be important fish producers, but also bring large number of tourists. Further complexity arises as we think of interactions between habitats: an estuary may host oyster reefs, seagrass beds and saltmarshes. Many fishery species move regularly between these habitats, others may migrate offshore as they mature, returning only to breed. They may thus depend on multiple habitats, or may be able to replace their reliance on one with the presence of another.

All too often, people take a simplistic approach to environmental management and development. If waves are a problem, we build a barrier. Seawalls and breakwaters are designed for this, and they can do it very well, but they don’t do anything else the way an ecosystem would.

In delivering multiple benefits, ecosystems are different. The challenge, however, is to bring these multiple values into markets where narrower visions typically hold sway. A seawall may be more effective than a saltmarsh at wave reduction, but if the saltmarsh is lost, fish production and carbon sequestration are also lost. The knock-on effects on fisheries are rarely the concern of engineers designing seawalls. Someone else pays the price.

When well managed, ecosystems should have the capacity to deliver benefits over very long time-scales. More remarkable still, when damaged they have a capacity for self-repair, with virtually no maintenance cost. How many seawalls can do that?

Ecosystem Services Flows

Of the benefits provided by ecosystems, some accrue to people within the ecosystem boundaries. In many cases, though, key ecosystem services attribute to people far from the provisioning ecosystem, either outside the ecosystem boundaries or even in other parts of the globe.

Vast areas of mangroves have already been converted to shrimp aquaculture ponds across Indonesia and the destruction continues, as shown here in Berau. The loss of mangroves emit significant amounts of carbon, which adds to the global issue of anthropogenic climate change.

Vast areas of mangroves have already been converted to shrimp aquaculture ponds across Indonesia and the destruction continues, as shown here in Berau. The loss of mangroves emit significant amounts of carbon, which adds to the global issue of anthropogenic climate change.

For example, a mud crab from a mangrove may be transported by boat or road to a market tens of kilometers from where it was caught. And its value may not end there. The crab may be sold on several time, generating additional value to shops and restaurants across a wide geographic space, before its final consumption. More complex still, is to consider tourists diving with sea lions in the Gulf of California. Their spending supports jobs and provides income to dive shops, hotels, boats and restaurants locally. Meanwhile airlines, hotel chains, car-rental companies, dive-kit and camera suppliers carry many of their profits to other countries, and such profits spread to shareholders, investors and even to pension-holders worldwide. Accordingly, a nature-based adventure in Mexico could provide benefits around the world.

 

Top image: ©Andrew Kornylak. Image credits: