Читать книгу The Atlas of Water - Maggie Black - Страница 29

Environmental Security

Florida Everglades

Aquatic ecosystems make a vital contribution to environmental security. Wetlands – bogs, swamps and marshes – maintain the viability of freshwater systems. Without them, rivers flow too fast, lakes become overburdened with organic matter, and coastlines are eroded. Until recently, the essential services provided by freshwater ecosystems have been economically under-valued. Marshes detoxify wastewater, upland forests conserve water and soil and mangrove swamps protect the coastline from erosion and storm surges – problems worsening with climate change. The loss of wetlands has been extensive. Around half of those in industrialized countries were destroyed before their importance was understood. They used to be seen as sources of “swamp fevers” such as malaria, and unproductive wet deserts that should be drained for settlement or agriculture. Some have been inundated or dried up as a result of dams altering river flows; others have had their water diverted for irrigation. Despite some reclamation, wetlands are deteriorating faster than any other ecosystem. Their destruction has a devastating impact on those who live in them and off them. The freshwater fish in inland wetlands provide vital protein for millions of people in developing countries. Attempts have been made to estimate the economic value of wetlands, some of which earn income from tourism and recreational activities as well as providing environmental benefits. In many cases, their worth turns out to be higher than that of the drained land.

The 2,000 km2 of Florida’s swamps represent only a fraction of their original size. In 1947, their ecological value was recognized by the creation of the Everglades National Park, but revival of the ecosystem has been stalled by the Florida sugar industry and farmers. In 2008, the Florida state government showed its commitment to ecological repair with a landmark decision to buy the US Sugar Corporation for $1.75 billion and use its land to restore flows of water to the Everglades from Lake Okeechobee.

The importance of mangroves