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Death Valley
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Plant and animal life
Lack of water makes Death Valley a desert, but it is by no means devoid of (没有) life. Plant life above the microscopic (宏观) level is absent from the salt pan (盐层), but salt-tolerant saltgrass and rushes grow around the marshes at its edges.
Mesquite (牡豆树) flourishes where less saline water is available.
Creosote bush (墨西哥三齿拉瑞阿，一种常青灌木) dominates the gravel (沙砾) fan (扇形地带) surfaces around most of the valley.
Cactus (仙人掌) is rare in the lowest part of the valley but abundant on the fans farther north. Spring rains bring out a great variety of desert wildflowers.
Animal life is varied, although nocturnal (夜间活动的) habits conceal many of the animals from visitors to the valley. Rabbits and several types of rodents (啮齿类动物), including antelope (羚羊), squirrels, kangaroo rats (更格卢鼠) and desert wood rats, are present and are preyed upon by coyotes (郊狼), foxes, and bobcats (短尾猫).
The largest native mammal in the area, and perhaps the best studied member of the fauna, is the desert bighorn sheep (加拿大盘羊).
Small herds of sheep are most commonly found in the mountains surrounding Death Valley but at least occasionally visit the valley floor. Wild burros (小驴), descendants of animals lost or abandoned by prospectors and miners, have become so numerous as to threaten, through overgrazing, the natural vegetation which other animals depend upon.
Visitors may gain the impression that the only birds present are the raucous (声音嘶哑) and numerous ravens (渡鸦), but the first biological survey of the valley, in the 1890s, reported 78 species of birds and nearly three times that number are now known to inhabit or visit the area. Lizards (蜥蜴) are numerous, snakes comparatively rare. (The end)(SD-Agencies)
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