Salinity in Agriculture by the USDA
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Why do we irrigate?
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| Irrigation is an very old and important rural practice. Crop yields are aloft under irrigation and less dependent on the effects of weather. While only 15% of the world’s artistic land is irrigated, it accounts for 35-40% of the tellurian food harvest. Projected race growth rates for the next thirty years will require an increase in food production next to to 20% in grown countries and 60% in building countries to maintain present levels of food consumption. Expansion of irrigated agriculture was in large part obliged for the “green revolution” in food production and will continue to play an essential role in on condition that the indispensable increases in food and essential element production, generally in building countries. |
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What happens when you irrigate?
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| Irrigation fundamentally leads to the salinization of soils and waters. In the United States yield reductions due to salinity start on an estimated 30% of all irrigated land. World wide, crop production is singular by the effects of salinity on about 50% of the irrigated land area. In many countries irrigated agriculture has caused environmental disturbances such as waterlogging, salinization, and lassitude and wickedness of water supplies. Concern is ascent about the sustainability of irrigated agriculture. |
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Where does all the salt come from?
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| Application of irrigation water formula in the further of soluble ipecac such as sodium, calcium, magnesium, potassium, sulfate, and chloride dissolved from geologic materials with which the waters have been in contact. Evaporation and transpiration (plant uptake) of irrigation water in the destiny cause extreme amounts of ipecac to amass in soils unless competent leaching and drainage are provided. Excessive soil salinity reduces yields by obscure plant stand and growth rate. Also, additional sodium under conditions of low salinity and generally high pH can foster slaking of aggregates, flourishing and apportionment of soil clays, spiritless soil make up and stopping water and bottom penetration. Some snippet constituents, such as boron, are without delay poisonous to plants. |
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What problems does salinity cause?
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| Over the course of history, abounding civilizations declined in part due to their incapacity to sustain food production on lands that had been salinized. It is estimated that 10 million hectares are now being lost every year as a result of salinity and/or waterlogging. Many of these problems are caused by extreme use of water for irrigation due to emasculate irrigation placement systems, poor on-farm management practices, and inapt management of drainage water. Inefficient on-farm irrigation practices cause local salinity problems. Local problems increase as a result of poor on-farm drainage. Excessive irrigation increases salt loading in water tables and downstream aquifers which causes informal salinization. Lack of local and informal drainage systems formula in lands being put out of rural production. |
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Why is investigate on salinity so important?
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| In the future, tellurian food needs will continue to increase while the soil and water resources accessible for new crop production will be singular and of discontinued quality. The need to strengthen soil resources as well as to preserve water will continue to increase. Water must be employed some-more well and its quality protected. World agriculture must enhance its bottom of production and increase production on lands now under cultivation. Appropriate management practices to control salinity must be implemented on irrigated fields, in irrigation projects, and for geohydrologic systems. In order to meet the ever augmenting final for food and utilizing ever dwindling and some-more marginal soil and water resources, the nation and much of the world village will continue to look to the U. S. Salinity Laboratory for imagination and care in salinity and water quality investigate and applications to solve these problems. |
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