Soil Conservation

views updated

Soil conservation

Soil conservation is the protection of soil against excessive loss of fertility by natural, chemical, or artificial means. It encompasses all management and land-use methods protecting soil against degradation, focusing on damage by erosion and chemicals . Soil conservation techniques can be divided into six categories, crop selection and rotation, fertilizer and lime application, tilth , residue management, contouring and strip cropping, and mechanical (e.g., terracing ).

While the potential dangers of chemical degradation and soil erosion were recognized as early as the American Revolution, it was not until the early 1930s that soil conservation became a familiar term. The soil conservation movement was a result of the droughts during the 1930s, the effects of water erosion, the terrific dust storms created by wind erosion in the Great Plains, and by the urging of Hugh Hammond Bennett.

Dr. Bennett, a soil scientist from North Carolina, recognized the erosion damage to previously arable land in the Southeast, Midwest, and elsewhere in the 1920s and 1930s. In 1929, he published a bulletin entitled "Soil Erosion, A National Menace" and started a successful personal campaign to get federal support, beginning with a $160,000 appropriation by Congress to initiate a national study. In 1933, the U.S. Department of the Interior named Bennett as head of the Soil Erosion Service, which conducted soil erosion control demonstrations nationwide. In 1935, the Soil Conservation Service , led by Bennett, was established as a permanent agency of the U.S. Department of Agriculture .

Soil degradation problems addressed include soil compaction , salinity build-up, and excessive soil acidity. Because soil and water are so intimately related, the program also deals with water conservation and water quality . Under M. L. Wilson, then Assistant Secretary of Agriculture, the Soil Conservation Service established conservation districts guided by elected officials assisted by Soil Conservation Service personnel. Currently there are more than 3,000 districts in the United States.

Sharing the cost of conservation became federal policy with the passage of the Soil Conservation and Domestic Allotment Act of 1936. The act funded the shift of croplands to "soil-building" crops and established soil conservation practices on croplands and grasslands . The Great Plains Conservation Program, enacted by Congress in 1956, sought to shift some of the highly erodible land from cropland to grassland. The Water Bank and Experimental Rural Clean Waters Programs were an attempt to resolve disputes over drainage of "potholes" in the Midwest and Great Plains and demonstrate the influence of soil and water conservation practices on water quality.

As early as the 1930s, the federal government began to purchase "submarginal" lands outright. The Conservation Reserve segment of the Soil Bank (1956-1960) bought substandard farmland to conserve soil and alleviate surplus crop production. The current Conservation Reserve Program , authorized in a 1985 farm bill, paid farmers to convert land from cropland to grassland or trees under a long-term lease. Currently the "sodbuster," "swampbuster," and conservation compliance programs attempt to force farmers to comply with soil and water conservation programs to be eligible for other government programs, such as price supports.

The role of the Soil Conservation Service has changed over the years, but its central mission is still to provide technical information for good land use . Today the Soil Conservation Service is highly concerned with environmental problems, water quality, wetland preservation, and prime farm land protection, as well as urban concerns related to their mission. The soil conservation movement has spawned a number of professional societies, including the Soil and Water Conservation Society and the World Association of Soil and Water Conservation.

[William E. Larson ]