GEOG 317 Lecture Notes - Gully, Mass Wasting, Soil Retrogression And Degradation
16 Dec 2012
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Document Summary
Soil erosion- detachment and transportation of soil or rock by wind, water, ice or gravity. Impacts on site- loss of productivity, nutrient and organic matter losses in topsoil. Impacts off site- sedimentation of water reservoirs and rivers, water treatment plants damaged. A or predicted erosion soil loss= rkl scp. Accelerated erosion- when people disturb soil or vegetation by grazing livestock, cutting forests, building roads or construction. Soil degradation types: surface soil erosion physical degradation- mass wasting, compaction, structure degradation by organic matter loss, subsidense of organic soils chemical degradation- acidification, salinization, alkalinization, and contamination. Water erosion type: sheet erosion- removal of fairly uniform layer of soil from land surface. Rill erosion- process in which numerous small channels several cm in depth form. Gully erosion- process when water accumulated in narrow channels and over short periods, removing soil over narrouw area to greater depth. Wind erosion- dry weather phenomenon, accelerated by soil moisture deficiency.
