**2.2 Solving the problem of soil salinity: how to reduce the salinity of underground water?**

With the expansion of the reclamation of saline land, the increase in water scarcity, and the dependence of countries on well water, however, the problems of salinity have increased and have become even more threatening to agricultural production [66]. Investors began to look for ways to solve the problem of soil

salinity, and researchers were interested in developing ways to reduce the proportion of salts in water [66–69]. In this report, we offer you several golden tips, which are the summary of experience and science in dealing with the problems of salinity in your farm or field: It is not wise for farmers in saline lands to wait to overcome the full salt problem before starting the commercial production cycle. Rather, it is wise to coexist with the problem and gradually overcome it by preparing the root region to coexist with the permitted limits of growth.

Soil permeability relationship with irrigation capacity of saline water: Land with good permeability is tolerated by irrigation with saline water up to 3000 ppm without the accumulation of salts or causing a problem [70]. Poor soil permeability is precipitated by water salts even if salinity is 200 ppm due to the accumulation of salts over time [71]. Calcium nitrate and urea were used as an alternative to nitrate as a source of nitrogen and calcium. Fertilizers containing sulfate, such as potassium sulfate, magnesium, manganese, and zinc, were used. Sulfuric acid is usually used through the irrigation operation by the (fertigation) techniques, whereas nitric and phosphoric acids are used with the organic matter during preparation for each new crop.

To reduce the harmful effect of salts in the well water, we must modify the ionic structure by adding some chemicals [72–74], which helps to precipitate the harmful constituents of carbonates and bicarbonates. The following relationships should also be known: sodium absorption ratio (SAR)/electrical conductivity (EC)/leaching ratio (LR), especially when using saline water, so that the soil does not deteriorate and decrease production. How to reduce the effect of water salinity on crops? To overcome the problem of salinity and achieve the highest productivity in the presence of salts, irrigation periods with the installation of long washing irrigation to remove the salts from the root area must be rounded. If the proportion of sodium in the irrigation water is to be considered, the approximate percentage of calcium or magnesium must be adjusted by adding calcium throughout the year.

The best source of calcium here is the agricultural gypsum because of its multiple benefits, which we will talk about in a separate report. Reducing salinity of wells by choosing irrigation method.

When sprinkling and high-water salinity, water droplets should be observed to be large and not misty. Irrigation is done at night so that the evaporation process decreases, and the salts are deposited on the leaves of the plant. Frequent drip irrigation without changing the lines or completely immersing the entire land once or twice a year will exacerbate the problem of salinity in the soil. In addition, irrigation of agricultural banks that have drainage water for farms and adjacent fields is the most dangerous to the future of the soil and will not be able to reduce the deterioration and desertification in the future. The large number of composts with fertilization of ammonium nitrate causes the salinity of the soil to be increased.

#### **2.3 Salinity ratio suitable for agriculture**

The problems of soil and water salinity are endless, and we have asked hundreds of questions about the best methods to be relied upon in agriculture. In the next report, we will review together important information on this subject, with an indication of the salinity ratio suitable for agriculture [75, 76]. Possible agricultural methods to avoid and reduce salinity damage based on nonreclaimed saline lands can be utilized as follows: Agriculture is on high lines with agriculture in the lower half of the miles because the salts bloom at its peak. The same method can be followed when farming on the terraces with the work of a small pyramid rise in the center of the terrace in order to bloom salts. Winter crops are preferred where the salt damage is less than that in the summer crops, and planting is preferred by seedling [57]. Drip irrigation helps to collect salts away from plants, so that the soil is washed from the accumulated

**63**

**Figure 1.**

*(2) 6 mm: 3 ton/fed; (3) 10 mm: 6.5 ton/fed.*

*Performance of Water Desalination and Modern Irrigation Systems for Improving Water…*

tion, drainage and treatment of salinity by following this process (**Figure 1**).

immersing or spraying with sprayers at a rate of 100 m3

washing requirements with a good drainage system.

This is done by the following equation:

conductivity of 1 mm/cm at 25°C are required [42].

area of root spread and drain away from the root zone.

The ECe, where there is no crop shortage, is 1.7 millimhos. Solution: washing needs of potato = 1 × (100/1.7) = 59%.

salts before planting the next crop. Methods of solving the problem of salinity of the soil to obtain the salinity ratio suitable for agriculture: Salinity treatment is not easy, so it is necessary to control and coexist with salts in soil. So as not to exceed the limits allowed by the integration of agricultural operations of plowing, fertilization, irriga-

Where soil samples are not analyzed, the following system shall be followed: The plowing of the earth is two orthogonal slits. To wash the soil, wash by irrigation by

of my squash per feddan + 200 kg superphosphate—this is for growing

salinity testing is recommended after each washing routine to determine the effect of washing on salinity and to know whether the washing process is continuing.

agriculture only, and the mixture is divided into 60 cm depth and 80 cm width. It is preferable to sterilize organic compost by sun or use organic manure. The organic fertilizer is composted in one area and is well soaked to saturation and covered with plastic for 2–3 months. Fertilizer rates are added with the addition of appropriate

**2.4 How are the washing needs of the plants that are added to the irrigation** 

**water determined to help achieve the appropriate salinity ratio for the plant?**

Laundry needs = salinity of irrigation water (mm) × (100/plant tolerance rate of

Example: The wet needs of potato plants irrigated with water with an electrical

In order to avoid any shortage in the potato crop, which is infused with salted water 1 ml/cm, it is necessary to increase the amount of water needed for each irrigation [48]. This is 59% as washing needs to wash the accumulated salts in the

*The ratio between mean of soil salinity and amount of gypsum annually adding. (1) 4 mm: 0.75 ton/fed;* 

per feddan once a week. Soil

+ 50 kg superphosphate is added to the line of

*DOI: http://dx.doi.org/10.5772/intechopen.87010*

vegetables. [45] In case of trees, 5 m3

Add 20 m3

salinity).

*Performance of Water Desalination and Modern Irrigation Systems for Improving Water… DOI: http://dx.doi.org/10.5772/intechopen.87010*

salts before planting the next crop. Methods of solving the problem of salinity of the soil to obtain the salinity ratio suitable for agriculture: Salinity treatment is not easy, so it is necessary to control and coexist with salts in soil. So as not to exceed the limits allowed by the integration of agricultural operations of plowing, fertilization, irrigation, drainage and treatment of salinity by following this process (**Figure 1**).

Where soil samples are not analyzed, the following system shall be followed: The plowing of the earth is two orthogonal slits. To wash the soil, wash by irrigation by immersing or spraying with sprayers at a rate of 100 m3 per feddan once a week. Soil salinity testing is recommended after each washing routine to determine the effect of washing on salinity and to know whether the washing process is continuing. Add 20 m3 of my squash per feddan + 200 kg superphosphate—this is for growing vegetables. [45] In case of trees, 5 m3 + 50 kg superphosphate is added to the line of agriculture only, and the mixture is divided into 60 cm depth and 80 cm width. It is preferable to sterilize organic compost by sun or use organic manure. The organic fertilizer is composted in one area and is well soaked to saturation and covered with plastic for 2–3 months. Fertilizer rates are added with the addition of appropriate washing requirements with a good drainage system.
