Problems of South Florida ecosystems

1. Each member of an ecosystem belongs to the environment of every other part of that system, so any change in one alters the environment for all the others. And as those components react to the alteration, they in turn continue to transform the environment for the others.

2. Since human beings first walked the earth, they have affected each ecosystem they have inhabited. For example, a century ago the interconnected Kissimmee River – Lake Okeechobee – Everglades ecosystem comprised one of the most productive and stable wetland regions on earth. But marsh and slow-moving water stood in the way of urban and agricultural development. Intricate systems of ditches and canals were built and, since 1900, half of the original 4 million acres of the Everglades has disappeared.

3. The Kissimmee River has been channelized into an arrow-straight ditch, and wetlands along the river have been drained. Levees have prevented water in Lake Okeechobee from contributing sheet flow to the Everglades, and highway construction has deviled the region, further disrupting natural drainage patterns. Fires have been more frequent and destructive, and entire biotic communities have been eliminated by lowered water levels. During excessively wet periods, portions of the Everglades are deliberately flooded to prevent drainage canals from overflowing. As a result, animals drown and birds cannot rest and reproduce. South Florida's wading bird population decreased by 95% within a hundred years.

4. Without the natural pu­rifying effects of wetland systems, water quality in South Florida has deteriorated, and with lower water levels, salt water encroachment is a serious problem in coastal areas. Today, backed by regional, state, and 227 federal agencies, scientists are struggling to restore South Florida's ailing ecosystems. There are extensive plans to allow the Kissimmee River to meander again across its former floodplain, to return agri­cultural land to marsh, and to restore historic water flow patterns through the Everglades.

5. The problems of South Florida should serve as a useful lesson. Alterations of the natural environment should not be undertaken without serious consideration of all the consequences. All citizens of the earth must understand the effects of their actions on the complex earth system.

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What plans do scientists have for restoring South Florida's ailing ecosystems?

Дата добавления: 2015-07-11