The Lower Colorado River : A Western System

نویسنده

  • Roy Johnson
چکیده

--A historic look at the Colorado River will illustrate the dras­ tic effects of human activity on most Western rivers. Engineering features for the management of water and electric power have resulted in increased evapora­ tion, associated salinity, and other physicochemical changes; drastic reduction in many native plant and animal populations; increasing populations of intro­ duced species; and changes in erosional and sedimentation rates. "On the map the Delta was bisected by the river, but in fact the river was nowhere and everywhere, for he could not decide which of a hundred green lagoons offered the most pleasant and least speedy path to the Gulf. So he traveled them all, and so did we. He divided and rejoined, he twisted and turned, he meandered in awesome jungles, he all but ran in circles, he dallied with lovely groves, he got lost and was glad of it, and so were we." -Aldo Leopold in "A Sand County Almanac." (1949).3 "It has withstood man's attacks longer than James Ohio Patie's Hee-1ay, (Gila) but in its function and even in its form, it is fast becoming a ditch. Dammed, artifica11y fed, stripped of its vegetation, its flow regulated, its wildlife depleted, the Verde is not merely tamed and domesticated, it is broken and emasculated not yet dead but mechanically lifeless, an uncomplaining servant, dutifully obedient to its master." -James W. Byrkit in "A Log of the Verde." (1978).

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تاریخ انتشار 2009