soil erosion & sedimentation
Post on 11-Feb-2016
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DESCRIPTIONSoil Erosion & Sedimentation. Primary Causes of Soil Erosion in The US. Poor Farming Practices Exposing bare soil to wind and rainfall increases soil erosion. Plowing parallel to slopes Overgrazing by domestic animals Deforestation Construction. Results of Erosion & Sedimentation:. - PowerPoint PPT Presentation
Poor Farming PracticesExposing bare soil to wind and rainfall increases soil erosion.Plowing parallel to slopesOvergrazing by domestic animals
The economic cost of soil erosion in the U.S. has been estimated as $44 billion a year.
Reduction of top soil depth impairs the lands productivity
Sediment creates muddy or turbid lakes and streams
Sediment fills ponds, lakes, reservoirs and waterways
Erosion can cause undermining and structural damage to buildings, roads and other structures.
Terracing prevents rapid surface run-off & soil erosion
Contour plowing across a slope following its elevation contour lines.
The rows formed have the effect of slowing water run-off during rainstorms and allows for percolation.
Growing crops from year to year without tilling the soil.Known as chemical farming
Terracing, cover cropsand retaining walls in Machu Picchu, Peru. Built about 1450
Gabions (from Italian gabbione meaning "big cage) are wire cages filled with riprap.Used for erosion control
Have some advantages over loose riprap:
ModularityAbility to be stacked in various shapesCan conform to ground movementCan dissipate energy from flowing waterFree draining
Cellular Confinement Systems