[ti:How Wetlands Help Protect Louisiana from Powerful Ocean Storms]
[by:www.21voa.com]
[00:00.00]更多听力请访问21VOA.COM
[00:00.04]A complex and costly flood prevention system
[00:04.24]helped protect New Orleans when Hurricane Ida
[00:08.32]hit the Louisiana city last week.
[00:11.36]Barriers, or seawalls, pumps and other controls blocked major flooding
[00:17.52]as the sea level rose sharply during the powerful storm.
[00:22.00]But something else helped keep the water out of the city:
[00:26.12]the area's coastal wetlands.
[00:28.56]These expanses of earth are covered in shallow water
[00:32.64]most or all of the time.
[00:35.08]Many kinds of animals, grasses and other plants
[00:39.20]make up the ecosystem.
[00:41.72]The Louisiana wetlands slowed,
[00:44.60]redirected and helped contain the flow Ida
[00:47.88]that pushed in from the Gulf of Mexico.
[00:52.32]"There is always a benefit
[00:54.00]by having these wetlands between you and the storm,"
[00:57.92]said Gerald Galloway.
[00:59.88]He is a former engineering professor
[01:02.76]and an expert on flood risks.
[01:05.44]He has served as an advisor to the U.S. Army Corps of Engineers.
[01:10.36]The wetlands had been shrinking for many years in Louisiana.
[01:15.60]The state launched a major effort to renew the area and barrier islands
[01:21.32]after the disastrous hurricanes Katrina and Rita of 2005.
[01:28.36]The plants and uneven ground of wetlands
[01:31.20]are part of the strong storm resistance the ecosystem provides.
[01:35.96]These elements slow and weaken the waterand winds
[01:39.76]as the storm moves inland toward people and property.
[01:44.80]Hugh J. Roberts is chief operating officer
[01:48.12]at the Water Institute of the Gulf,
[01:50.84]an environmental research group.
[01:53.64]He said wetlands "help with storm protection
[01:57.44]because they are dissipating energy."
[02:00.56]In other words, wetlands help absorb the storm's energy.
[02:05.92]Wetlands are generally most effective at lessening the harm
[02:09.92]from small to moderate surges of ocean water, said Ed Link.
[02:15.56]He is a researcher at the University of Maryland.
[02:19.72]He also was the leader of an examination
[02:23.36]of New Orleans' storm protections' after Hurricane Katrina.
[02:29.44]With bigger storms like Ida,
[02:31.64]the protection the wetlands can offer may be more limited.
[02:36.28]Once the wetlands are full of water,
[02:39.12]they lose their ability to slow down waves.
[02:42.48]Storms can more easily travel over them, Link said.
[02:48.12]Still, experts say natural barriers offer one more line of defense
[02:53.28]even with major storms and they can make a difference.
[02:58.04]Louisiana has been spending large amounts of money
[03:01.92]to restore its natural barriers to help protect against storms.
[03:06.88]Since 2007, the state has created
[03:11.00]or restored around 197 square kilometers of marshland
[03:16.64]and 97 kilometers of barrier island.
[03:20.84]Marshland is a kind of soft wetland.
[03:25.28]The state's most recent coastal protection and restoration plan
[03:29.92]includes several projects that build or protect
[03:33.52]more than 2,072 square kilometers of land.
[03:38.96]The total cost of such work is estimated to be $50 billion.
[03:44.28]But the projects are expected to prevent more than
[03:47.92]$150 billion in damage over the next 50 years.
[03:53.44]Even with such efforts, the state's restoration work
[03:57.96]cannot keep up with its land losses.
[04:02.28]Louisiana has been losing land since at least the 1930s.
[04:07.24]Flood control measures along the Mississippi River
[04:11.12]stopped the natural process that left materials from the river
[04:15.68]in the delta – the low-lying land next to the river.
[04:20.72]In 2012, state officials predicted
[04:23.88]their restoration work would someday stop the problem.
[04:27.88]Five years later, they were no longer making that prediction.
[04:32.80]The Louisiana Coastal Protection and Restoration Authority
[04:37.48]now says the restoration is simply slowing down the land loss.
[04:43.00]I'm Ashley Thompson. 更多听力请访问21VOA.COM
END OF TRACK. "END OF TRACK." The two men bowed. "Whoever was that person you were talking to?" she enquired, as soon as they stood together. The took of triumph faded from her eyes, she had grown worn and weary. The roses were wilting on the walls, the lights were mostly down now. Hetty, looking in to see if anything was wanted, found herself driven away almost fiercely. I only saw Master Jervie once when he called at tea time, The year 1747 was opened by measures of restriction. The House of Lords, offended at the publication of the proceedings of the trial of Lord Lovat, summoned the parties to their bar, committed them to prison, and refused to liberate them till they had pledged themselves not to repeat the offence, and had paid very heavy fees. The consequence of this was that the transactions of the Peers were almost entirely suppressed for nearly thirty years from this time, and we draw our knowledge of them chiefly from notes taken by Horace Walpole and Lord Chancellor Hardwicke. What is still more remarkable, the reports of the House of Commons, being taken by stealth, and on the merest sufferance, are of the most meagre kind, sometimes altogether wanting, and the speeches are given uniformly under fictitious names; for to have attributed to Pitt or Pelham their[112] speeches by name would have brought down on the printers the summary vengeance of the House. Many of the members complained bitterly of this breach of the privileges of Parliament, and of "being put into print by low fellows"; but Pelham had the sense to tolerate them, saying, "Let them alone; they make better speeches for us than we can make for ourselves." Altogether, the House of Commons exhibited the most deplorable aspect that can be conceived. The Ministry had pursued Walpole's system of buying up opponents by place, or pension, or secret service money, till there was no life left in the House. Ministers passed their measures without troubling themselves to say much in their behalf; and the opposition dwindled to Sir John Hinde Cotton, now dismissed from office, and a feeble remnant of Jacobites raised but miserable resistance. In vain the Prince of Wales and the secret instigations of Bolingbroke and Doddington stimulated the spirit of discontent; both Houses had degenerated into most silent and insignificant arenas of very commonplace business. "It certainly will be. Miss Widgeon," answered Maria, with strictly "company manners." "One who has never had a brother exposed to the constant dangers of army life can hardly understand how glad we all feel to have Si snatched from the very jaws of death and brung back to us." "Just plug at 'em as you would at a crow, and then go on your way whistlin'?" persisted Harry. "Hurroo!" echoed Hennessey; "that's the ticket." "Come forward, keeper," continued the baron, "and state how these arrows came into your hands!" "Yes." HoMEJULIA京香2018下载
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