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Highly Erodible Land
In United States agricultural policy, Highly erodible land (HEL) refers to land that is very susceptible to erosion, including fields that have at least 1/3 or of soils with a natural erosion potential of at least 8 times their T value. About of cropland meet this definition of HEL, according to the 1997 National Resources Inventory. Farms cropping highly erodible land and under production flexibility contracts must be in compliance with a conservation plan that protects this cropland. See also *Tillage erosion Tillage erosion is a form of soil erosion occurring in cultivated fields due to the movement of soil by tillage. There is growing evidence that tillage erosion is a major soil erosion process in agricultural lands, surpassing water and wind erosion ... References {{DEFAULTSORT:Highly Erodible Land Erosion United States Department of Agriculture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and waves; glacial plucking, abrasion, and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows. The rates at which such processes act control how fast a surface is eroded. Typically, physical erosion procee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Value
The United States Department of Agriculture defines the T Value as the maximum average soil loss (in tons per year) that will still allow economical maintenance of the current level of production into the future. References United States Department of Agriculture {{Agri-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Resources Inventory
The National Resources Inventory (NRI) is a periodic assessment of the status and changing conditions of the soil, water, and related resources on private land conducted by USDA’s Natural Resources Conservation Service (NRCS). The survey has been conducted at 5-year intervals since 1977, most recently in 2007, though a 2010 mid-cycle data release occurred in December 2013. NRCS released initial results from the 1997 survey in late 1999. The 2010 report includes comparison of the data relative to 1982. Summary pages exist for soil erosion Soil erosion is the denudation or wearing away of the upper layer of soil. It is a form of soil degradation. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, air (wind), plants, and ..., land use status and trends, development of non-federal rural land, and rangeland. External links NRI website(contains results from the 2010 survey, as well as archived results from 1997. Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Production Flexibility Contracts
In the United States, a production flexibility contract is a 7-year contract covering crop years 1996-2002, authorized by the 1996 farm bill (P.L. 104-127) between the Commodity Credit Corporation (CCC) and farmers, which makes fixed income support payments. Farmers were given production flexibility and diversification options on their contract acres not previously allowed on base acres. Each farm’s total payment was the payment rate times the payment quantity for participating base acres. In exchange for annual fixed payments, the owner or operator agreed to comply with the applicable conservation plan for the farm, the wetland protection requirements currently in law, and the constraints on growing fruits and vegetables on contract acres. Land enrolled in a contract had to be maintained in an agricultural or related activity. The law stated that not more than $35.6 billion would be paid over the 7-year period, in declining annual amounts from $5.3 billion in FY1996 to $4.0 billi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tillage Erosion
Tillage erosion is a form of soil erosion occurring in cultivated fields due to the movement of soil by tillage. There is growing evidence that tillage erosion is a major soil erosion process in agricultural lands, surpassing water and wind erosion in many fields all around the world, especially on sloping and hilly landsGovers, G.; et al. (1999). “Tillage erosion and translocation: emergence of a new paradigm in soil erosion research”. Soil & Tillage Research 51:167–174.Lindstrom, M.; et al. (2001). “Tillage Erosion: An Overview”. Annals of Arid Zone 40(3): 337-349. A signature spatial pattern of soil erosion shown in many water erosion handbooks and pamphlets, the eroded hilltops, is actually caused by tillage erosion as water erosion mainly causes soil losses in the midslope and lowerslope segments of a slope, not the hilltops. Tillage erosion results in soil degradation, which can lead to significant reduction in crop yield and, therefore, economic losses for the farm.T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and waves; glacial plucking, abrasion, and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows. The rates at which such processes act control how fast a surface is eroded. Typically, physical erosion procee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
