To realize the effect of tourism on our planet, as well as the importance of a growing sustainable tourism, we need to understand one of the basic planet’s natural capital: the ecosystem.

An ecosystem is an interdependent, functioning system of plants, animals and microorganisms. It can be as large as a desert, or as small as a local pond. Without the support of the other organisms within their own ecosystem, life forms would not survive, much less thrive. Such support requires that predators and prey, fire and water, food and shelter, clean air and open space remain in balance with each other and with the environment around them.

Ecosystem “services” are the benefits that humans obtain from ecosystems that are produced by the interactions within themselves. These include supporting services like nutrient recycling, oxygen production and soil formation that are essential to life and to maintaining all ecosystems; provisioning services like food, fiber, water and fuel; regulating services such as climate regulation, flood control, water quality and disease control. In combination these represent the planet's natural capital.

The earth as an ecosystem is changing, attributable in great part to the effects of globalization and man. More carbon dioxide is now in the atmosphere than has been in the past 650,000 years. This carbon stays in the atmosphere, acts like a warm blanket, and holds in the heat — hence the name ‘global warming.’ Check out our “Climate Change” section for more information on this matter.

The ecosystems most threatened with degradation are ecologically fragile areas such as alpine regions, rain forests, wetlands, mangroves, coral reefs and sea grass beds. The threats to and pressures on these ecosystems are often severe because such places are very attractive to both tourists and developers.