Year 11 | 10 December 2019 | TO ENTER | TO REGISTER

Salty irrigation water

Irrigation water quality is dynamic by the total dissolved solids and total amount and types of chlorides present in the water. A salt is a multiple of two elements or ions, one has a positive charge and one has a negative. This how sodium and chloride are able to insert to one another.

Saltwater intrusion happens when saltwater is drawn-in (from the sea) into freshwater aquifers. This function is caused because sea water has a aloft firmness (which is because it carries some-more solutes) than freshwater. This difference in firmness causes the vigour under a mainstay of saltwater to be larger than the vigour under a mainstay of the same tallness of freshwater. If these two columns are continuous at the bottom, afterwards the vigour difference would cause a upsurge of saltwater mainstay to the freshwater mainstay until the vigour equalizes.

The upsurge of saltwater internal is singular to coastal areas. Further inland, the freshwater mainstay is aloft due to the augmenting rise of the land and is able equate the vigour from the salt water, dwindling the saltwater intrusion. The aloft water levels internal have another effect: the freshwater flows seaward. This completes the picture: at the sea-land boundary, at the high part of the aquifer freshwater flows out and in the lower part, saltwater flows in. The saltwater intrusion forms a wedge.

Pumping of fresh water from an aquifer reduces the water vigour and intensifies the effect, sketch salt water into new areas. When freshwater levels drop, saltwater intrusion can ensue inland, reaching the pump site for the well. Then, saltwater which is non-professional for celebration or irrigation, is pumped up out of the ground. To forestall this, some-more and some-more countries have adopted endless monitoring schemes and numerical models to consider how much water can be pumped without causing such effects.

High salinity irrigation water contains many ipecac together with sodium chloride, sodium sulfate, and magnesium chloride, and sodium bicarbonate. This is customarily personal as the total dissolved solids (TDS) or total salt concentration (TSC). For well water, quality depends on the subterraneous formations from which the water is pumped. Municipal water is treated at the local station, depending upon the water treatment practical salinity levels can still be high.

Plants pull water through their roots, up to their leaves where it evaporates to the atmosphere. This is called the evapotranspiration process. Salinity restricts this by obscure the total water intensity in the soil. Salts end up competing with plants for water. Even if a salty soil is water saturated, the roots are incompetent to catch the water and plants show signs of dry weather stress. These signs are base burn, yellow leaves, defoliation, and the plant being incompetent to produce a yield. The soil will also become unenlightened and form hard crusty layers on the aspect creation water incompetent to dig into the ground.

Usually, crop yield is independent of salt concentration when salinity is below some starting point level, afterwards yield progressively decreases to zero as the salt concentration increases to the turn which cannot be tolerated by a since crop. The problem occurs when the plant roots take up the ipecac and blockage occurs in the plants which restricts water from issuing through the plant.

Plants can continue to grow in the participation of low ipecac but the yield intensity will never be maximized. Plants grown in salty soils or irrigated with salty water are always in a dry weather stressed condition.

Professor Mark Tester, from the School of Agriculture has settled that “Salinity affects the growth of plants worldwide, quite in irrigated land where one third of the world’s food is produced. And it is a problem that is only starting to get worse, as vigour to use less water increases and quality of water decreases. Farmers need to find new ways of “Helping plants to withstand this salty onslaught to our groundwater that will have a significant stroke on world food production.”

by S. C.
15 october 2009, Food & Fun > Nature