Equipment Specs

Land reclamation refers to the process of repairing or restoring disturbed land to a useful state. Land reclamation is an important part of the construction, mining, forestry, and agricultural industries, as those industries generally disturb the soil with the use of heavy earthmoving machinery. When land is disturbed, it is sometimes necessary for it to undergo reclamation, not only to help the environment flourish, but so it can be of use once again to these industries.

Land is used for many reasons:

  • For the extraction of natural resources, such as in mining
  • For the extraction of fruits, vegetables, and grains
  • For raising livestock
  • To build structures and buildings
  • To raise animals and grow food
  • To harvest trees and plant new ones [1]


[edit] History

Reclamation has been practiced for centuries. Farmers reclaimed land by irrigating regions neglected by rainfall or by draining marshes and wetlands. By the 20th century, several irrigation projects were carried out in the U.S., Pakistan, and the Soviet Union, when it became evident how much damage to the environment could occur if reclamation projects were not initiated.

One of the first American attempts to regulate reclamation came at the foot of the Carey Land Act in 1894. The Act set focus on conserving natural resources and acknowledged that farming, grazing, and deforestation, teamed with little rainfall, was having a hazardous impact on the land.

In 1902, the U.S. Bureau of Reclamation passed an act to supply water to farmers for disturbed lands throughout 17 western states. The process of irrigation increased the sustainability of the land, but unfortunately may have resulted in the land incurring selenium and salinity poisoning.[2]

The Reclamation Act of 1902 put the onus on the federal government to make better use of reclamation projects. Within the next two or three decades, land reclamation became a dire need, as the drought of the 1920s and 1930s led to the existence of more land in need of restoration. The Bureau of Reclamation and the U.S. Army Engineers Corps began working together in land reclamation by building dams. The Flood Control Act of 1944 also worked to give the federal government more control over this issue. [3]

In the U.S., the Bureau of Reclamation of the Department of the Interior has played a significant role in land reclamation projects and in providing irrigation to arid and semiarid lands scattered throughout the western states.

One of the biggest attempts at reclamation in the U.S came from the U.S. Surface Mining Control and Reclamation Act of 1977. The act called for mining companies that employed strip mining processes to restore the land they exposed.[4]

One of the biggest reclamation projects in the world began in 1920 in the Netherlands. The project involved reclaiming land from an inlet of the North Sea known as Zuider Zee. A dam crossing the inlet was built and a lake called the Ijsselmeer was formed.

[edit] Types

Land reclamation is important to the health and sustainability of the environment and wildlife. When large regions of land are damaged by machinery or other elements, it results in the inability of vegetation, and the wildlife that depends on it, to flourish.

There are various other reasons for land reclamation to occur. In some instances, beaches are in need of restoration. Wind and water erosion can have a dire effect on beach sediment, sometimes requiring alternatives to be sought out to maintain the area.

Land reclamation is also important to the agricultural industry. Farmers often restore wetlands and marshes by draining them. This process converts once-unusable land into farmland that can be used for growing fruits, vegetables, and grains, and for raising livestock.

In the construction of a series of man-made islands in Dubai, the United Arab Emirates, including the World Islands and the Palm Islands, dredgers were used to pump sand from the seabed in order to formulate more beaches. The project was one of the biggest land reclamation projects in the world.

Similarly, desert land can also be reclaimed and involves providing provisions for water and soil stabilization.

[edit] Process

In order to reclaim land, studies must be conducted to understand what soil was like in its original state, including any characteristics it might have, its vegetation, and how it has been altered. [5]

Depending on the damage to the soil, it may be necessary to employ irrigation or drainage in order to restore soil that has been damaged through mining, erosion, or earthmoving processes. [6]

One of the biggest contributors to disturbed land is surface mining, which accounts for half of the total land area classified as damaged in the U.S.[7] In surface mining, the top layer of rock, known as overburden, is removed and the lower layers of soil and rock are exposed. The removal of overburden drastically alters the chemical and physical properties that are returned to soil. These properties react badly for seed germination and can kill or prevent plant growth. Without soil cover and vegetation, wind and water erosion can pollute nearby streams with sediment. [8]

Similarly, strip mining for coal also significantly impacts the quality of soil. Because of this, contractors are required to restore the land as per U.S. Surface Mining Control and the Reclamation Act of 1977. This process involves filling in excavations that were made in order to obtain the coal; grading the land to prevent deep slopes; and placing the original topsoil on the graded surface. Some vegetation is planted as well in order to encourage growth.[9] Unfortunately, even when topsoil is replaced, vegetation doesn’t always flourish due to sediments having coarse texture and containing fragmented rock. The result is sometimes land that has low fertility. [10]

Other methods of restoring land include the use of fertilizers to change the texture and mineral content of the soil, irrigation, drainage, and flood control.

[edit] References

  1. Environmental Reclamation. AB Heritage. 2008-11-05.
  2. Reclamation. Answers. 2008-11-05.
  3. Reclamation. Answers. 2008-11-05.
  4. Reclamation Info. How Stuff Works. 2008-11-05.
  5. Environmental Reclamation. AB Heritage. 2008-11-05.
  6. Reclamation Info. How Stuff Works. 2008-11-05.
  7. Reclamation. Answers. 2008-11-05.
  8. Reclamation. Answers. 2008-11-05.
  9. Reclamation Info. How Stuff Works. 2008-11-05.
  10. Reclamation. Answers. 2008-11-05.