A Bill Moyers Report on Ecosystems defines them as follows: "Ecosystems are communities of interacting organisms and the physical environment in which they live. They are the combination and interaction of the plants, animals, minerals, and people in any given area of the Earth. A small bog, a single sand dune, or a tiny patch of forest is an ecosystem."
There are several major types of ecosystems. Agroecosystems include farms where we grow food and raise livestock. Forest ecosystems include woodlands where we cut timber and hunt. Freshwater ecosystems include lakes and streams where people fish and get drinking water. Grassland ecosystems consists of meadows, prairies and savannas. Coastal ecosystems include beaches, reefs, marshes, and other areas that define our coastlines. Urban ecosystems are cities and towns where most of the human population lives and operates.
Ecosystems provide goods and services that populations depend on for survival. Half of all the jobs in the world revolve around agriculture, fishing and forestry. Ecosystems purify the air people breath and the water people drink, and they help control global climates as well.
Roy Clapham coined the term "ecosystem" in 1930. His definition simply stated that ecosystems were the combined biological and physical features of an environment
Governments around the globe are uniting to preserve ecosystems---the Convention on Biological Diversity is a group effort by more than 100 countries. The Convention defines its objectives as follows: "1. To conserve biological diversity. 2. To use biological diversity in a sustainable fashion. 3. To share the benefits of biological diversity fairly and equitably."