Introduction
is also known as Greatramericandert.
One of the main natural geographical districts of North America. Beiba Horse has some river Delta, South to the Grand River in the Grante, the east of the Lauren, the low plateau and the inland low plain, and the west to the Landfound Mountains. 4800 kilometers long in north and south, 480 to 1120 kilometers wide. The area is about 2.9 million square kilometers. Western high is low, 1800 meters east of 200 meters from the Rocky Shandong, gradually dropped to 450 meters. The construction is the central land of North America, which has a deep self-echo-neonating level deposition rock, ground flat, and known to the large plain. Temperate continental semi-arid climate, annual precipitation is 300 ~ 600 mm, and there are fewer east. Eastern development has a community in Pleya. The soil layer is deep and fertile, the water is premium, which is the most important agricultural area of North America, wheat, corn, cotton, soy, livestock, etc. Minerals such as oil, coal, natural gas.
Malands south to Glander, north and North Bohai shore, the horses in the northbrocks, the East, Dongjie, lowland and Canada, Sida Rocky Mountains, a major natural geography in North America Area. The length is about 4,800 km (3,000), width 500 ~ 1,100 km (300 ~ 700), with an area of about 2.9 million square kilometers (1125,000 square 哩), generally equal to 1/3 of the United States. 10 states in the United States (Montana Tay, North Dakota, South Dakota, Wyoming, Nebraska, Kansas, Colorado, Oklahoma, Texas and New Mexico) and Canada 3 Grassland (Manitoba, Saskatchewan) There are also part of the Northwest China in the northwest. Some of them use Western 100 ° lines to their eastern bounds, but more accurate lines are 100 ° wire slightly, Dicosas, Texas, North Dakota, East Steep Cliff. In Canada, the boundary between the large plain and the Canadian land shield passes through Winnipeg, and then turned to the northwest to bypass Asbasca, Lake Lake, Big Bear Lake. At the north, the big plain is brought to the Arctic Ocean with a narrowly in the horse.
The American Grand Plain is one of the famous plains in the world. It actually continues to Canada. In the territory of the United States, its basic boundaries are: 1800 meters above sea level in the foothills of the mountains; East to Mississipi River Valley, approximately 300 meters above sea level; North to Canada's Saskatchewan Wenhe (saskatchewan); south to the south of Texas. The American academic community has different understandings for the eastern boundaries of the large plain, generally considered to be nearly 97 °.
The American plain includes Montana, Wyoming, Colorado, New Mexico, North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, Texas, etc. There are 640 kilometers wide in the east and the north and the south (including Canada).
Geological
Large plain, a sedimentary rock, a sedimentary rock, the sea, the shallow water, mainly composed of slowly inclined shale, limestone, sandstone, etc., the thickness is 5 kilometer. Most of the surfaces of this region are young Lu Xiang Seiji flooding accommodation, and the glacier substances in the north are not covered in consecutive, as well as loess sediments. In general, the geology is relatively simple, and geological exercise is not strong. However, there are two regions to form a clear control in the large plain: 1, Badland (Badland): Form a very vulnerable area, its rock is shale, occasionally a heavy rain can cause ground Quite vigorous erosion, forming a unique deep valley cliff, there is a hundred feet of small hills in the valley, there are still a few hundred feet of hills; 2, Montenell (Blackhill): The area is far higher than the surrounding plain surface, and Sufficient rainfall makes pine forests, birch grows very lush. Among them, the rock is sandstone, which is a good reservoir, which is the main source of water in eastern South Dakota.
Miles Plain
Grand Plain is a semi-arid grassland vast plateau, called the American desert. In the United States, the Rocky Mountains face 1,500 ~ 1,800 meters (5,000 ~ 6,000 feet) at sea level (5,000 ~ 6,000 feet), and the eastern border is reduced to 1,500 呎. Canada is low, close to the North Ocean floor is only slightly higher than the sea. Some areas are very flat, such as the Estadacado of the Esta, the east of Texas, and New Mexico; other areas have forest dense mountains with 1,500 ~ 2,000 feet from the ground, such as South Dakota, Brack, and Meng Bearpaw Mountain, Daxue Mountain and Judith Mountain.
Desert it is a fairly complete plain, slowly inclined from the West, and the human eye can't feel its slope, about 2 meters per kilometer. Along the No. 80 highway in the United States, wear this wide land, and your heart is sturdy. A leappeath wrote: "The origin is the poem, the palate should also be embarrassed, the burning, the Yingying Valley, the Yingying Valley, the Yingying, the chase day, the room has a thoughts, Chest's own hilly, life is full of peach plums. "
The appearance of the large plain is flat, slowly tilting east, only in three areas are blocked by undulation: 1, Montenegro: it is a crystalline rock block (about 50 miles long, 20 Mile width, ie 80 × 32 km), invading the flat plain deposition, forming a rush; 2, along the area of Colorado to the New Mexico border, the ancient erosion of a lava cover is above the plain; 3, by pine The Lingshi (close to Nebraska to the Wyoming) broke the integrity of the plain, this area and different erosion occurred. At the same time, due to climate and soil conditions, large plains are also known as "Dustbowl).
Climate
Grand Plain is a continental climate. Most of the winter cold summer heat, less precipitation, small humidity, multi-wind, and temperature change. Moisture is mainly from the Gulf of Mexico, and the north and western moisture are extravagant. The annual rainstorm in the southern plains is 380 ~ 640 mm (15~25 吋), 12 ~ 15 吋 in the northern plain, 25 inch the eastern edge of Nebrasga, the western edge of Montana is less than 15 吋. The southern precipitation of the Canadian Plain area is 10 ~ 20 吋, the growth period is 70 ~ 110 days. The growth period of Texas is 240 days, beautiful, plus border in 120 days, 70 ~ 110 days of grassland.
Continental Climate
Climate is a semi-arid continental climate, winter cold summer heat. When there is a cold wave in winter, the temperature can decrease a lot, and severe frost can be distributed to Texas. However, if there is a warm air called Chi-Nooks in winter, it is extremely advantageous. In winter and spring, this kind of wind often blows in the southeast direction, combining ice and snow, increases temperature, and is beneficial to the grazing of livestock. However, when it is called the winter storm for Belizards, it produces a storm, accompanied by heavy snow, which has great disasters to animal husbandry. Summer is very hot, but the night is cool, the temperature is large, the temperature difference is more than 33 ° C in the most hot moon in the middle of the year. The annual precipitation is less than 500 mm, local changes, seasonal changes, and extraientation variations are quite large, and the stability of agricultural production has brought a great threat.
Weather disaster
On the large plain, the main weather disaster type has the following: 1. Daries: Has certain periodic changes; 2, dust storm: due to land drought, loose, plus strong disturbance of strong wind and airflow, there are many dust storms; 3, flood: especially due to rainstorm, in the summer, there is a flooding; 4, Lu Dong volume: annual From April, it often occurs, although it is partial, but the destructive is very large.
River
The river on the plain is basically originated from the Rocky Mountain. From the West East crossing the plain, the Mississippi River is finally injected, and the famous river has the Missouri River, the Plate River, A Kansas River, etc.
In the United States, the Missouri River and its tributary (Huangshi River, Pratt [Platte] River, Kansas River) and the Arkansas River from the Rocky Mountains to the large plain from the large plain Valley. In Canada, the Saskatchewan and its trials are the main rivers.
Ecology
Vegetation
The natural vegetation of the large plain is dominated by grass, the east is medium, the high grassland, the western part is short Grassland. There is a large plant, such as silk, calendering. However, many natural grass have been opened as farmland. Along along the river tree, there are tall-resistant hardwood species, such as Ye Yafeng and Triangula Yang. Evergreen conifer (mainly) is growing in the mountain forest belt, such as Brack Mountain. Between the Winnipeg, Albenda and Manitoba, Canada, has a transition zone of northwest-southeast, named "Parklands", from here, grassland gradually replaced forests, Vegetation north of north latitude is mainly coniferous forest.
Grassland Vegetation
Zone plant type is a grasslaky vegetation, which is composed of shorten (also known as water beef grass), and scattered Deciduous trees, the most common for cotton wood (Cottonwood) is distributed along the plain river valley, and there is also a pine tree on the non-agricultural land of stone. Since people are huge, the grassland is destroyed, over-reclamation, etc., causing the natural vegetation type on the large plain very unstable. The natural grassland before the development is suitable for large-scale grazing. Once they are deepened, the grassland is extremely difficult to recover. Therefore, the natural protection of vegetation and soil in large plains has always been a major problem.
Animals
settled in European settlement, with a group of grassy grass animals in the large plain: American Bison and fork. The American Bison has now disappeared, but the fork is still pruning. Other animals with agricultural interests and adapt to the grassland environment with a grassland dog rat, jungle wolf and a snake. There are moose, woodland North America reindeer, Canada, North America Reindeer, Canada, and Gray Wolf.
Agricultural farming
large plain soil fertilizer, suitable for agricultural farming, has high organic matter content. However, if there is no sufficient humidity and biological protection, it is very susceptible to the wind erosion, and the severity of the wind is amazing.
The large plain is still still a agricultural area, producing wheat, cotton, sorghum and hay, breeding cattle and sheep. There are 8 in the United States mainly produce 8 (Kansas, North Dakota, Texas, Montana, Nebraska, Colorado, Oklahoma and South Dakota) are in the original, and the grassland is the main production of Canada. Wheat area. Mineral resources are also very rich. Wyoming, North Dakota, Montana and Colorado coal reserves are among the best in the US Zhuzhou. Oil and natural gas production in Abada, Texas, USA, accounts for the first place in the country.