Ecosystems are constantly exchanging materials through the movement of air in the atmosphere, the flow of water in rivers and the migration of animals across the landscape. People, however, have also established themselves as another major driver of connectivity among ecosystems. In the June 2008 Special Issue of Frontiers in Ecology and the Environment, titled Continental-scale ecology in an increasingly connected world, ecologists discuss how human influences interact with natural processes to influence connectivity at the continental scale. The authors conclude that networks of large-scale experiments are needed to predict long-term ecological change.
We know that the world has always been connected via a common atmosphere and the movement of water, says Debra Peters, an author in the issue and a scientist with the United States Department of Agricultures Agricultural Research Service (USDA-ARS). The world is also becoming highly interconnected through the movement of people and the transport of goods locally to globally. Among ecologists, there is an increasing realization that these connections can have profound influences on the long-term dynamics of ecological systems.
The transport of many types of materials, including gases, minerals and even organisms, can affect natural systems. This movement results in greenlash, which occurs when environmental changes localized to a small geographic area have far-reaching effects in other areas. For example, a drought in the 1930s caused small-scale farmers to abandon their farms across the U.S. Midwest. The absence of crops intensified local soil erosion, leading to powerful dust storms. Large amounts of wind-swept dust traveled across the continent, causing the infamous Dust Bowl and affecting air quality, public health and patterns of human settlement throughout the country.
Because of increasing globalization, people often inadvertently introduce non-native plants, animals and disea
|Contact: Christine Buckley|
Ecological Society of America