Irrigation water quality is of the utmost importance for agriculture
Plant nutrients are largely found in the soil in the form of salts that, when dissolved in the water that the soil contains, can be absorbed by the roots.
Irrigation water quality is of the utmost importance for agriculture and affects planning of both the irrigation regime and of the irrigation system.
Salts in soils have multiple origins, ranging from the decomposition of rocks, to the influx of sea water in coastal zones (referred to as marine intrusion), excessive application of fertilizers, or the use of saline irrigation water. Normal soluble salt concentrations in the soil are not likely to cause problems for good crop development. But when those concentrations are excessive, growth can be diminished.
In irrigation systems, use of saline irrigation water entails the risk of salinizing the soil, and in many cases can result in lower crop production. Other significant problems that might be caused by saline irrigation water are toxicity for the plants, water infiltration into the soil, and blockage in localized irrigation systems.
Its quality can be ascertained with a high degree of precision
Through timely analyses, the irrigation water’s quality can be ascertained with a high degree of precision. Such awareness is fundamental prior to instituting an irrigation regime, since there are numerous aspects whose determination depends upon water quality, such as selection of the irrigation system or of the crop itself, the irrigation equipment’s components, or the type of treatments to be given to the water in order to use it for irrigation.
Other aspects, such as drainage network sizing, can be determined once irrigation water quality has been analyzed and soil flushing needs are understood. In addition to be an important selection criterion, irrigation water quality and, in particular, salt content, are a necessary indicator for proper irrigation management and balancing of salts in the root zone, and for avoiding the above-mentioned problems to the extent possible.
Irrigation water quality is a prime factor for selecting irrigation systems, determining their components, and deciding how to manage irrigation and the crop itself in order to avoid problems of salinity, water infiltration in the soil, toxicity for plants, or problems derived from blockage in localized irrigation systems.
All irrigation water contains dissolved salts that are contributed to the soil. This sometimes increases soil salinity and makes it harder for the plants to absorb the water.
Dissolved salt quantities need to be ascertained, which can be accomplished by measuring electrical conductivity through a laboratory analysis. Upon determining salt content, a number of response strategies can be developed.
Boron, sodium, and chloride are the salts that can pose the most severe toxicity problems for plants. Woody plants tend to be more sensitive than annual plants, and the plants’ symptoms depend upon which salt is provoking the toxicity.
Water infiltration problems can occur when certain levels of sodium content are surpassed in the soil in relation to those of calcium and magnesium, which is known as the sodium adsorption ratio.
In order to evaluate water quality for irrigation overall, certain criteria are generally established, based on salt content and on the sodium adsorption ratio.
Salt flushing is often used to prevent excessive salt concentration in root zones. It consists of applying an extra amount of water with the irrigation to dissolve the salts, allowing them to travel down to deeper parts of the soil.
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We are experts in agriculture chemistry and plant-soil-water monitoring control systems.
The great value that AGQ Labs brings to the agriculture sector is our global team of expert chemical engineers, agronomists, and scientists. Together, our experts utilize AGQ Labs’ vast reference database of ideal plant-soil-water conditions to optimize crop cultivation for our customers.
All our agronomic decisions are based on internally developed proprietary methods using AGQ Labs’ patented lysimeter suction probes and patented crop nutritional monitoring (US PTO# 9,107,341) that mimic water and nutrient uptake of roots.
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