|
The Ohio River, which streams westward from Pittsburgh, Pennsylvania, to Cairo, Illinois, is the largest tributary, by volume, of the Mississippi River in the United States. At the confluence, the Ohio is considerably bigger than the Mississippi (Ohio at Cairo: 281,500 cu ft/s (7,960 m3/s);〔Frits van der Leeden, Fred L. Troise, David Keith Todd: ''The Water Encyclopedia'', 2nd edition, p. 126, Chelsea, Mich. (Lewis Publishers), 1990, ISBN 0-87371-120-3 (long term mean discharge)〕 Mississippi at Thebes: 208,200 cu ft/s (5,897 m3/s)〔USGS stream gage (07022000 Mississippi River at Thebes, IL (long term mean discharge) )〕) and, thus, is hydrologically the main stream of the whole river system, including the Allegheny River further upstream. The river flows through or along the border of six states, and its drainage basin includes parts of 15 states. Through its largest tributary, the Tennessee River, the basin includes many of the states of the southeastern U.S. It is the source of drinking water for three million people.〔(ohioriverfdn.org: "Ohio River Facts" )〕 It is named in Iroquoian or , lit. "Good River" or and ''Spelewathiipi''. The river had great significance in the history of the Native Americans, as numerous civilizations formed along its valley. For thousands of years, Native Americans used the river as a major transportation and trading route. Its waters connected communities. In the five centuries before European conquest, the Mississippian culture built numerous regional chiefdoms and major earthwork mounds in the Ohio Valley, such as Angel Mounds near Evansville, Indiana, as well as in the Mississippi Valley and the Southeast. The Osage, Omaha, Ponca and Kaw lived in the Ohio Valley, but under pressure from the Iroquois to the northeast, migrated west of the Mississippi River to Missouri, Arkansas and Oklahoma in the 17th century. In 1669, René-Robert Cavelier, Sieur de La Salle led a French expedition to the Ohio River, becoming the first Europeans to see it. After European-American settlement, the river served as a border between present-day Kentucky and Indian Territories. It was a primary transportation route for pioneers during the westward expansion of the early U.S. In his ''Notes on the State of Virginia'' published in 1781–82, Thomas Jefferson stated: "The Ohio is the most beautiful river on earth. Its current gentle, waters clear, and bosom smooth and unbroken by rocks and rapids, a single instance only excepted."〔(Jefferson, Thomas, 1743–1826. Notes on the State of Virginia ); the ''single instance'' refers to the former rapids near Louisville.〕 During the 19th century, the river was the southern boundary of the Northwest Territory. It is sometimes considered as the western extension of the Mason–Dixon Line that divided Pennsylvania from Maryland, and thus part of the border between free and slave territory, and between the Northern and Southern United States or Upper South. Where the river was narrow, it was the way to freedom for thousands of slaves escaping to the North, many helped by free blacks and whites of the Underground Railroad resistance movement. The Ohio River is a climatic transition area, as its water runs along the periphery of the humid subtropical and humid continental climate areas. It is inhabited by fauna and flora of both climates. In winter, it regularly freezes over at Pittsburgh but rarely further south toward Cincinnati and Louisville. At Paducah, Kentucky, in the south, near the Ohio's confluence with the Mississippi, it is ice-free year-round. Paducah was founded there because it is the northernmost ice-free reach of the Ohio. ==Gallery== File:Allegheny Monongahela Ohio.jpg|The Allegheny River, left, and Monongahela River join to form the Ohio River at Pittsburgh, Pennsylvania, the largest metropolitan area on the river. File:Wheeling Suspension Bridge Lithograph.jpg|The 1849 Wheeling Suspension Bridge was the first bridge across the river. File:LouisvilleNightSkyline2-small.jpg|Louisville, Kentucky, sits at the widest and deepest point of the Ohio River. File:Donna York.jpg|A barge hauls coal in the Louisville and Portland Canal, the only man-made portion of the Ohio River. File:Cincinnati-skyline-from-kentucky-shore-night.jpg|The Tall Stacks festival celebrates the riverboats of Cincinnati, Ohio, every three or four years. File:Evansvilleskyline.jpg|Evansville, Indiana, the third-largest city in Indiana and the fourth-largest city on the river. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ohio River」の詳細全文を読む スポンサード リンク
|