Soil salinization is one of the most vital soil problems for agricultural production. Salinization refers to the salt content of the level affecting agricultural and environmental health.Soil salinization usually occurs in arid areas, In these areas, soluble salt ions accumulate in the soil. In these areas where plant growth requires irrigation, the Evaporation and transpiration process leaves salt in the soil.At the beginning, salt will reduces soil productivity and limits crop yields. As the salt content increases, it kills the vegetation and soil microorganism.
As a result, The perfectly fertile soil will became completely barren.
Several factors contribute to an increase in the amount of salt in the soil:
The total amount of dissolved salt in irrigated water and its composition affect soil salt content.The more water you irrigate, the salinity of the soil will be close to the salt concentration of the irrigation water. When the soil is dry, the concentration of salt in the soil will be increased.In addition, the poor soil drainage leads to low permeability, salt will accumulates on the soil surface.
Some fertilizers contain high contents of potentially harmful salts, such as potassium chloride or ammonium sulfate. Overuse and abuse of fertilizer leads to increasing salinity in soil.
In arid areas(High evaporation and transpiration), Plant high water-consuming crops that plants absorb groundwater from the roots through capillary action, leaving salt accumulation.
The impacts of salinity include:low agricultural productivity, low economic return and soil erosion.
In saline soils, sodium replaces calcium and magnesium, so aggregation of soil particles is reduced, and the soil will tend to disperse. When soil gets wet, it’s water infiltration capacity reduces as well. When dry, sodic soil becomes hard has the tendency to crack.
Salinity affects almost all process of plants’ growth.
1.Osmotic Stress
This is the principle cause of reduced plant growth and yield as salinity mounts. Water moves into plant roots by this process,which is controlled by the level of salts in the soil water.High salts concentration results in high osmotic potential of the soil solution, so the plant has to use more energy to absorb water. Under extreme salinity conditions, plants may be unable to absorb water and will wilt, even when the surrounding soil is saturated.
2.Specific Ion Toxicity
Some ions (particularly chloride) are toxic to plants and as the concentration of these ions increases, the plant is poisoned and dies.The immune resistance of plant becomes low, stunted growth,leaf burn,and necrosis become obvious as the level of salinity increases.
Apply minimal levels of irrigation water volume and keep the well-drained soil condition.
This is one of the best ways to deal with a soil salinity problem, especially if you are just starting out. Plant salt-tolerant cash crops such as barley, sunflowers, or canola. Not only are they equipped to deal with the salt, but also drought tolerant.
Flushing the soil is the process of using a low-salt water to irrigate the area and wash the salt below the root zone.
Trichoderma harzianum keep the soil environment rich in most kinds of nutrients via nitrogen fixation, release of plant growth regulating substances and bio degradation of organic matter in the soil etc. In addition, trichoderma has super adaptability in saline-alkali soil and reproduce rapidly. It’s the important method to reduce the salt content in soil. And environment friendly.For many soil conditions, multiples solutions of combination of the will be the better choice.
