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is a global process. It involves both the physical loss and the reduction in quality of topsoil associtated with nutrient decline and contamination
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The loss of the upper soil horizons containing organic matter and nutrients and the thinning of soil profiles reduces crop yields on degraded soils.
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soil degradation can cancel out gains from improved crop yields.
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a range of management strategies can be employed to reduce soil degradation. Many of strategies used can be subdivided into mechanical methods and cropping techniques.
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management strategies - mechanical methods commencer à apprendre
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mechanical methods focus on preventing or slowing the movement of rainwater fownslope and reducing the impact of wind on the soil
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afforestation/ reforestation commencer à apprendre
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afforestation/ reforestation have been widely used comprehensively over sizeable areas.
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the selection of the areas to be forested is of crucial importance, with steeper slopes being the natural starting point
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contour ploughing is a tried and trusted techniuque which prevents the downslope movement of water and soil.
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the planting of trees in shelterbelts and the use of hedgerows can do much to dissipate the impact of strong winds, reducing the wind's ability to disturb topsoil and erode particles,
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various cropping techniques can be employed to reduce soil degradation commencer à apprendre
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converting land from arable to pastoral uses - the planting of grass helps to bind soil particles together, reducing the action of wind and rain
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including grasses in crop rotations
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selecting and using farm machinery carefully, in particular avoiding where possible the use of heavy machinery on wet soils to prevent damage to the soil structure and using low ground pressure set-ups on machinery when possible
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encouraging biological diversity by planting several different types of plants together
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using reduced or shallow cultivation to maintain or increase near-surface organic matter
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