Headway 10

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question English réponse English
soil degradation
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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
soil degradation 2
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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.
soil degradation 3
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soil degradation can cancel out gains from improved crop yields.
management strategies
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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.
management strategies - mechanical methods
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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
afforestation/ reforestation
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afforestation/ reforestation have been widely used comprehensively over sizeable areas.
afforestation 2
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the selection of the areas to be forested is of crucial importance, with steeper slopes being the natural starting point
refforestation 3
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contour ploughing is a tried and trusted techniuque which prevents the downslope movement of water and soil.
refforestation 4
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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,
various cropping techniques can be employed to reduce soil degradation
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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
cropping techniques 2
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including grasses in crop rotations
cropping techniques 3
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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
cropping techniques 4
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encouraging biological diversity by planting several different types of plants together
cropping techniques 5
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using reduced or shallow cultivation to maintain or increase near-surface organic matter

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