刚看到的新闻:犹他州盐湖的水开始回升。 (图)

来源: 阿姗 2005-06-11 14:14:49 [] [博客] [旧帖] [给我悄悄话] 本文已被阅读: 次 (3839 bytes)


BRIGHAM CITY, Utah - The water in the Great Salt Lake has begun rising again after years of drought, changing the landscape and starting to submerge one of Utah's best-known artifacts: an enormous earth sculpture called the Spiral Jetty. The six years of drought had allowed the curious to flock to the lakeside to see the 1,500-foot-long, salt-encrusted spiral that Robert Smithson built in 1970 using backhoes to pile up rock and earth. For decades before the dry spell, the jetty had largely been just out of sight beneath the surface of the salty water. Thanks to a winter of record snowfall, it's not just the spiral Jetty that is changing. "Change in lake levels can produce significantly more of a change than you'd expect," says Maunsel Pearce, chairman of the Great Salt Lake Alliance, a consortium of conservation groups with interests in the lake. "You really need to see it to believe it." Sandbars exposed during the drought are now covered with water. Wetlands that had dried into sheets of cracked mud and thin dry grasses are now soggy marshes sprouting thick vegetation. Water also is inching back toward Antelope Island, although boat docks there remain beached. The lake's elevation averages about 4,200 feet above sea level, a level at which water spreads out across about 1,700 square miles, according to data kept since 1875 by the U.S. Geological Survey. But the drought that began in 1999 dropped the surface by about 6 feet, shrinking the lake to just 950 square miles. As of Saturday, it had gone back up a bit less than 4 feet, according to a USGS Web site. Such fluctuations are part of what makes the lake beautiful, says Lynn de Freitas, executive director of Friends of the Great Salt Lake. Each climate pattern changes the lake and people's perception of it, she said. "I guess my excitement is that the lake has the ability to breathe. Those droughts are part of the natural cycles of the lake," she said. The Great Salt Lake is a remnant of the ancient Lake Bonneville, which more than 12,000 years ago covered some 20,000 square miles of what is now Idaho, Utah and Nevada. Although just glimmer of its former self, the Great Salt Lake still is the world's fourth largest "terminal lake," where water flows in but doesn't flow out. Water delivered to the lake by four rivers is lost only through evaporation, which concentrates its mineral content, leaving behind a harsh solution in which only salt-tolerant species of brine shrimp, bacteria and algae can survive. Mineral companies extract selenium and magnesium from the lake bed. Commercial fishermen harvest brine shrimp. Each of those industries and recreational users were affected by the drought and will be again by the rising water, de Freitas notes. Rising water in the north arm of the lake will dilute the salty water where the Spiral Jetty sits and stimulate bacterial growth that turns the water pinkish-red, offering a different vision of the sculpture, de Freitas said. "The drama of the ability to see the jetty, I think now is actually improved," she said. "Now the water and is coming up and lapping at the jetty and even though you're slogging through the water, there's still a vague visible presence. I think people will find it more in keeping with the photographs they've seen." ___ On the Net: Spiral Jetty: http://www.spiraljetty.org/ US Geological Service: http://ut.water.usgs.gov/greatsaltlake/index.html
请您先登陆,再发跟帖!

发现Adblock插件

如要继续浏览
请支持本站 请务必在本站关闭Adblock

关闭Adblock后 请点击

请参考如何关闭Adblock

安装Adblock plus用户请点击浏览器图标
选择“Disable on www.wenxuecity.com”

安装Adblock用户请点击图标
选择“don't run on pages on this domain”