Text 2ARead the text to find answers to the given questions. Read the Notes to the text. 1) What could be said about the Everglades ecosystem a century ago? 2) Why has half of the original area disappeared? Find the reasons for that. 3) What is the result of urban and agricultural development of the Everglades?
As we continue to explore space, we are learning more and more about the world in which we live. 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 – Everglades¹ ecosystem comprised one of the most productive and stable wetland regions on earth. But sawgrass marsh² and slow-moving water stood in the way of urban4 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. The Kessimmee River has been channelized into an arrow-straight ditch, and wetlands³ 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.
Notes to the text 1 the Everglades – национальный парк в США 2 saw grass marsh – торфяные болота 3 wetlands – заболоченные земли 4 urban – городской
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