How did the human activities change the natural environment of the great plains in the early 1900s

Plains are one of the most important type of physical features of earth's surface. Plains are usually flat and low height from their surrounding areas. Most of the plains are the result of natural processes like aggradation and degradation. Some plains have elevation between 500 ft. with slight slope. Earth's surface comprised on approximately 40% on plains. Most of the plain areas are located in northern hemisphere. Most of the plain areas of Canada and USA are the result of glacial processes. World's biggest river basins depend on these plains. For example, Indus Basin, Ganga & Brahmaputra, Yung-Ci-Kiang, Nile, Dajla & Frat, Amazon, Mississippi and many others under the processes of winds and other processes.

Although, plains are called the source of human's needs, civilization and culture. And world's 80% population live on plains. The basic needs of human such as food, cloth and residence are mostly done by plains. However, all plains around the world have not similar characteristics. Some of World's plains are un-inhabitant due to extreme weather conditions. For example; the plains of Tindra and Syberia and the plain areas of Sahara Desert. Plains are known as the treasure of agricultural products for their fertility and smooth surface.