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SOIL. Rendzina soil, White Horse Hill, Berkshire Downs. What is a soil?. Collins English Dictionary defines soil as, “the top layer of the land surface of the earth that is composed of disintegrated rock particles, humus, water, and air.”. Soil Functions. Plant water supply
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SOIL Rendzina soil, White Horse Hill, Berkshire Downs
What is a soil? Collins English Dictionary defines soil as, “the top layer of the land surface of the earth that is composed of disintegrated rock particles, humus, water, and air.”
Soil Functions • Plant water supply • Plant nutrient supply • Aeration • Support
Agricultural soil problems • Salinization- particularly in areas with irrigation agriculture. Not a new problem (e.g. Mesopotamia) • Erosion- problems are caused by two major agencies, wind and water.It is estimated that agricultural topsoil is now being lost between 16 and 300 times faster than it can be replaced. Processes responsible for soil formation are very slow, requiring 200 to 1,000 years to form 2.5 cm of topsoil.
Industrial soil problems • Contaminated land- approximately 100,000 contaminated sites in the UK • Acid rain and soil acidity- results mostly from the burning of sulphur-rich fossil fuels to produce sulphur dioxide, and during the process of combustion by oxidation of nitrogen present in the air to form nitrogen oxides. Parys Mountain, Anglesey