Mississippi river

 Mississippi river water quantity biggest class. Located at the US in eastern part. The source has Para to agree the Asian mountainous region, southwest flows, the main current by Arab League forces Geni River and not the agriculture adds Greece to pull the river to converge nearby the Pittsburgh fort to become, nearby Illinois's Cairo, pours into the Mississippi river. Span 2100 kilometers, drainage area 52.8 ten thousand square kilometers. The main class has the card Nuowa river, the Kentucky base river, bashes fertile the river, the Cumberland river and the Tennessee River. In basin precipitation abundant rich, year precipitation 1000 long and fine hair rice. Rivers by rain water supplies primarily, water volume abundant rich, raises for the Mississippi river 56% water volume, the river mouth annual mean current capacity amounts to for 7080 cubic meters/seconds. Spring is the flood period, the dry season time in the autumn, the water level change is not whole year big. From the Pittsburgh fort to Portsmouth is the upstream, the river valley is narrow, average wide is smaller than 800 meters; Portsmouth to Cairo is a downstream, extends slightly compared to the upstream. The entire river gradient is not big, total head 130 meters, current of water slow slow. The Heavenly Stems and the Earthly Branches class always being open to navigation course approximately 4000 kilometers, and have transport the river and Lake Erie are interlinked, whole year all may be open to navigation. Has been in the US eastern part the important shipping lane, mainly loses delivers the coal, the sand and crushed stone, the petroleum, the iron, the steel material, the grain and the lumber and so on. Constructs has 19 levels of movable gates and width 91.4 meters, the deep 3 meters routes. Heavenly Stems and the Earthly Branches running water transport charges source abundant rich, the development degree is high. Ohio