The Great Plains (English " Great Plains " ) are a dry area east of the Rocky Mountains in North America. Geographically, they are the classic prairies of the American West, today they are used intensively for agriculture. They range from the Canadian " Prairie Provinces " (Alberta, Saskatchewan and Manitoba ) to Texas; sometimes a small part of Mexico is counted them.
The Great Plains cover an area of about 2 million square kilometers and extend a total of about a width of 500 km. While they are still about 1600 m high in the Rocky Mountains, they fall to the east to about 600 m.
One can divide the Great Plains in two climatic regions, since one west of the 100th meridian a scanty rainfall average encounters (less than 500 mm per year), whereas the eastern region has a relatively humid climate. According dominated in the west livestock and east of the cereal crops.
To the north are the Great Plains by the Canadian Shield, south by the coastal plain of the Gulf of Mexico.
The western boundary is the Rocky Mountains.
The eastern boundary is defined differently. Some geographers connect all of the edges of the plane which lie at 600 m altitude, and define the resulting line as the eastern border. Others draw the line further east and look at North Dakota, South Dakota, Nebraska and Kansas each fully as part of the Great Plains.
The Great Plains were inhabited long time sparse and were roamed by nomadic Indians in part on the hunt for bison and pronghorn. It was not until the Europeans brought to America by horses that came to this area in the 18th century, allowed the Indians a denser settlement of the prairie and the emergence of the Plains Indians. Some folks have benefited greatly from the new way of life, the bison hunting on horseback. The previously weak Lakota and Comanche, for example, developed within a short time to significant power factors in the Midwest. The lifestyle of the plain peoples was based heavily on the bison. They lived in tipis that could be assembled and disassembled quickly, and so attracted by the buffalo. In the 1930s - especially 1935-1938 originated in the Great Plains, the so-called Dust Bowl. After the large-scale clearing of prairie grass and a drought there had been soil erosion. This led to high dust strikers and mass poverty among the peasants who migrated increasingly towards California.
Middle of the 19th century, white settlers moved through the Great Plains to the west. For a long time the area as uninhabitable desert, until about 1865, settled many settlers. The stock numbers of bison were subsequently through massive hunting sharply, while the resident Indians were displaced to 1890 in reserves.
In 2007 there were about ten million people in the territory of the Great Plains, while the figure in 1950 was just under five million. However, it lost in recent decades settlements in the area and small towns by aging and depopulation strongly to population and population growth was concentrated in a few metropolitan areas primarily in Colorado and Texas. Approximately 2/3 of all counties in the region lost population, about 20%, by more than half. More and more small towns are transformed into so-called ghost towns. Increasing drought made it difficult to agriculture in recent decades considerable and the mechanization made workers redundant. The Ogallala aquifer, a deep aquifer is depleted by the use of artificial irrigation almost. Already today, cultivated land converted back to grassland, on the increasingly bison farm is operated. Under the name Buffalo Commons is proposed to reconvert large areas in prairie, abzusiedeln people and for wild bison to open the surfaces again. Hunting and tourism could open up a new economic base. In addition, the use of the Great Plains today focuses more and more on wind power generation.
The agricultural use of the Great Plains can be divided roughly into two areas. While west of the 100th meridian is mainly to be found in large livestock farms that is east of the 100th meridian of agriculture the primary agricultural use form. Attached is mainly Sommer-/Winterweizen as well as corn and sorghum. The reason for this distribution is the line of equal rainfall ( isohyet 500 mm), which runs almost parallel to the 100 longitude and forms the border for rainfed agriculture without irrigation.
The precipitation -rich east of the area, called the Wheat Belt (wheat belt ), is also called the breadbasket of the United States, or as the "bread basket" ( bread basket ), since in that region a huge surplus is generated in agricultural products. Approximately half of the wheat of the United States is produced in the territory of the Great Plains, which at 68 million tonnes for the entire United States (as of 2008) thus corresponds to about 34 million tonnes. In the Western High Plains 60 % of the beef produced in the USA, which is why this part of the Great Plains is often referred to as " Cattle Country " (cattle country). As far as agriculture is taking place in the West, it is possible usually by artificial irrigation.
One of the largest regions of the Great Plains, which were not temporarily subjected to agricultural use, including the Sand Hills in Nebraska. This is a very large area of contiguous sand dunes that are stabilized by low vegetation. 85 percent of this region, therefore, still have the original plant material.
Due to various forms of erosion measures had to be taken.
- The " minimum tillage " in which the stubble is not plowed after harvest, but be stamped by a machine with grooves is sown once again in the. Thus, the evaporation is reduced and the structure of the topsoil is preserved.
- The "Dry Farming" describes an annual exchange between cultivation and fallow to allow a water absorption of the fallow soil. Here, the soil is still plowed from the rain and rolled after rain to prevent drying out of the soil by evaporation and erosion of soil by wind.
- The " Contour plowing " promotes the infiltration of water by vertically -aligned furrows are drawn into the field, which slow down the water, so that the two forces of wind and water erosion is counteracted. Overall, the problem of wind erosion is significantly harder to solve than caused by water erosion forms.
- By mulching the soil is a large area covered with unverrottetem organic material to prevent the topsoil is eroded by the wind.