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Chicago began life in 1779 (1) a small trading post on the Chicago River. A farsighted black freedman, Jean du Sable, did a flourishing fur (2) with the Native Americans. When his trading post became a fort and then a city, it was (3) Chicago. This is the Native American word for the wild onions found in the area.In 1820 Chicago (4) ten or twelve houses and a store or two. Now it is the third largest city in the (5) , and still it continues to grow. Thousands of new buildings are (6) every year. They are built to accommodate new businesses and residences. More than seven (7) people now live in and around the city.Astride the crossroads of the nation, Chicago is the largest railroad (8) in the world. No other city in the land is a larger trucking center. The city, (9) on lake Michigan, is the largest inland port in the world. O’Hare Airport is the world’s busiest commercial airport. Overall, Chicago is the leading (10) center in the United States.Its location in the heart of North America’s farmland (11) Chicago the world’s largest grain market. It also plays (12) each year to more than a thousand conventions. In 1860 Abraham Lincoln was nominated for President at the Republican convention (13) here. That was to establish a pattern for both the Democratic and Republican parties since that time. Half of all major (14) conventions have taken place in Chicago.But Chicago did not achieve success without problems. At one time pollution from the Chicago River (15) the city’s water supply from Lake Michigan. (16) pure drinking water, the engineers reversed the course of the river (17) it flowed backwards, away from the lake! This kept the water supply (18) . Even the famous fire of 1871 could not snuff out the spirits of the vital young giant. The entire central city was (19) , but citizens built anew. And they erected the first towering structure of steel and concrete. In doing so, they invented the (20) Today, as an example, Chicago’s impressive skyline includes the world’s tallest building. The 1454 foot Sears Tower. 9().
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Every minute of every day, what ecologist James Carlton calls a global "conveyor belt" redistributes ocean organisms. It’s a planet wide biological disruption that scientists have barely begun to understand.Dr. Carlton—an oceanographer at Williams College in Williamstown, Mass. —explains that, at any given moment, "there are several thousand [marine] species [traveling].., in the ballast water of ships. " These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous invasion of fish destroying, pipe-clogging zebra mussels.Such voracious invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly—or even beneficially—join the local scene. But some will make trouble.In one sense, this is an old story. Organisms have ridden ships for centuries. They have clung to hulls and come along with cargo. What’s new is the scale and speed of the migrations made possible by the massive volume of ship—ballast water taken in to provide ship stability—continuously moving around the world...Ships load up with ballast water and its inhabitants in coastal waters of one port and dump the ballast in another port that may be thousands of kilometers away. A single load can run to hundreds of thousands of gallons. Some larger ships take on as much as 40 million gallons. The creatures that come along tend to be in their larva free floating stage. When discharged in alien waters they can mature into crabs, jellyfish, slugs, and many other forms.Since the problem involves coastal species, simply banning ballast dumps in coastal waters would, in theory, solve it. Coastal organisms in ballast water that is flushed into midocean would not survive. Such a ban has worked for the North American Inland Waterway. But it would be hard to enforce it worldwide. Heating ballast water or straining it should also halt the species spread. But before any such worldwide regulations were imposed, scientists would need a clearer view of what is going on.The continuous shuffling of marine organisms has changed the biology of the sea on a global scale. It can have devastating effects as in the case of the American comb jellyfish that recently invaded the Black Sea. It has destroyed that sea’s anchovy fishery by eating anchovy eggs. It may soon spread to western and northern European waters.The maritime nations that created the biological "conveyor belt" should support a coordinated international effort to find out what is going on and what should be clone about it. According to Dr. Carlton, ocean organisms are ().
Chicago began life in 1779 (1) a small trading post on the Chicago River. A farsighted black freedman, Jean du Sable, did a flourishing fur (2) with the Native Americans. When his trading post became a fort and then a city, it was (3) Chicago. This is the Native American word for the wild onions found in the area.In 1820 Chicago (4) ten or twelve houses and a store or two. Now it is the third largest city in the (5) , and still it continues to grow. Thousands of new buildings are (6) every year. They are built to accommodate new businesses and residences. More than seven (7) people now live in and around the city.Astride the crossroads of the nation, Chicago is the largest railroad (8) in the world. No other city in the land is a larger trucking center. The city, (9) on lake Michigan, is the largest inland port in the world. O’Hare Airport is the world’s busiest commercial airport. Overall, Chicago is the leading (10) center in the United States.Its location in the heart of North America’s farmland (11) Chicago the world’s largest grain market. It also plays (12) each year to more than a thousand conventions. In 1860 Abraham Lincoln was nominated for President at the Republican convention (13) here. That was to establish a pattern for both the Democratic and Republican parties since that time. Half of all major (14) conventions have taken place in Chicago.But Chicago did not achieve success without problems. At one time pollution from the Chicago River (15) the city’s water supply from Lake Michigan. (16) pure drinking water, the engineers reversed the course of the river (17) it flowed backwards, away from the lake! This kept the water supply (18) . Even the famous fire of 1871 could not snuff out the spirits of the vital young giant. The entire central city was (19) , but citizens built anew. And they erected the first towering structure of steel and concrete. In doing so, they invented the (20) Today, as an example, Chicago’s impressive skyline includes the world’s tallest building. The 1454 foot Sears Tower. 1().
Chicago began life in 1779 (1) a small trading post on the Chicago River. A farsighted black freedman, Jean du Sable, did a flourishing fur (2) with the Native Americans. When his trading post became a fort and then a city, it was (3) Chicago. This is the Native American word for the wild onions found in the area.In 1820 Chicago (4) ten or twelve houses and a store or two. Now it is the third largest city in the (5) , and still it continues to grow. Thousands of new buildings are (6) every year. They are built to accommodate new businesses and residences. More than seven (7) people now live in and around the city.Astride the crossroads of the nation, Chicago is the largest railroad (8) in the world. No other city in the land is a larger trucking center. The city, (9) on lake Michigan, is the largest inland port in the world. O’Hare Airport is the world’s busiest commercial airport. Overall, Chicago is the leading (10) center in the United States.Its location in the heart of North America’s farmland (11) Chicago the world’s largest grain market. It also plays (12) each year to more than a thousand conventions. In 1860 Abraham Lincoln was nominated for President at the Republican convention (13) here. That was to establish a pattern for both the Democratic and Republican parties since that time. Half of all major (14) conventions have taken place in Chicago.But Chicago did not achieve success without problems. At one time pollution from the Chicago River (15) the city’s water supply from Lake Michigan. (16) pure drinking water, the engineers reversed the course of the river (17) it flowed backwards, away from the lake! This kept the water supply (18) . Even the famous fire of 1871 could not snuff out the spirits of the vital young giant. The entire central city was (19) , but citizens built anew. And they erected the first towering structure of steel and concrete. In doing so, they invented the (20) Today, as an example, Chicago’s impressive skyline includes the world’s tallest building. The 1454 foot Sears Tower. 6().
Every minute of every day, what ecologist James Carlton calls a global "conveyor belt" redistributes ocean organisms. It’s a planet wide biological disruption that scientists have barely begun to understand.Dr. Carlton—an oceanographer at Williams College in Williamstown, Mass. —explains that, at any given moment, "there are several thousand [marine] species [traveling].., in the ballast water of ships. " These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous invasion of fish destroying, pipe-clogging zebra mussels.Such voracious invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly—or even beneficially—join the local scene. But some will make trouble.In one sense, this is an old story. Organisms have ridden ships for centuries. They have clung to hulls and come along with cargo. What’s new is the scale and speed of the migrations made possible by the massive volume of ship—ballast water taken in to provide ship stability—continuously moving around the world...Ships load up with ballast water and its inhabitants in coastal waters of one port and dump the ballast in another port that may be thousands of kilometers away. A single load can run to hundreds of thousands of gallons. Some larger ships take on as much as 40 million gallons. The creatures that come along tend to be in their larva free floating stage. When discharged in alien waters they can mature into crabs, jellyfish, slugs, and many other forms.Since the problem involves coastal species, simply banning ballast dumps in coastal waters would, in theory, solve it. Coastal organisms in ballast water that is flushed into midocean would not survive. Such a ban has worked for the North American Inland Waterway. But it would be hard to enforce it worldwide. Heating ballast water or straining it should also halt the species spread. But before any such worldwide regulations were imposed, scientists would need a clearer view of what is going on.The continuous shuffling of marine organisms has changed the biology of the sea on a global scale. It can have devastating effects as in the case of the American comb jellyfish that recently invaded the Black Sea. It has destroyed that sea’s anchovy fishery by eating anchovy eggs. It may soon spread to western and northern European waters.The maritime nations that created the biological "conveyor belt" should support a coordinated international effort to find out what is going on and what should be clone about it. The identified cause of the problem is ().
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