soil.mep
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SUSTAINABLE SOIL MANAGEMENT
often be unaware of the process since its effects are easily covered up by tillage. A more advanced form of rill erosion is gully erosion. Gullies can cause substantial damage to fields and cannot be corrected by tillage.
Wind erosion can occur even on flat land if the land has no vegetative cover and is dry. When particles of fine silt or clay and organic matter are transported by the wind, they carry the nutrients they have absorbed with them. This selective displacement of soil material leaves behind impoverished, coarse-textured soil particles. ▲ Gully erosion Environmental damage caused by wind erosion includes the pollution of the air by fine dust particles and the covering of fertile land with infertile deposits. In extreme cases, productive land can be buried under dunes. Water erosion, on the other hand, can – in addition to reducing soil quality and productivity – carry phosphorus into bodies of fresh water, which can increase the risk of eutrophication, or the over-enrichment of water with nutrients. In areas with high accumulations of nutrients in the soil because of the excessive application of animal manure or the inappropriate use of mineral fertilizers, nutrients are more prone to leach into groundwater or rivers or be carried overland with run-off to nearby surface waters. ▲ Wind erosion
N u t r i e n t - r i c h w a t e r s c a n re s u l t i n a h i g h e r- t h a n - a v e r a g e growth of algae, the decomposition of which can lead to oxygen starvation in the water, killing fish and other aquatic life forms.
Soil under pressure Another form of soil degradation is compaction, which occurs when soil particles are compressed by heavy machinery or the trampling of animals. Compaction reduces the soil's porosity, and when this happens, plant roots are less able to penetrate the soil. In addition, water drainage and air diffusion are restricted. Wet clays are more susceptible to compaction than sandy soils. The ▲ Bad timing and inappropriate equipment damage the soil's structure.
negative effects of soil compaction can be remedied to varying degrees depending on the structural damage, by using special tillage techniques to break up the soil.
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