The main difference between saline and alkaline soils is that saline soils have a pH of less than 8.5 and exchangeable sodium less than 15%, while alkaline soils have a pH of more than 8.5 and exchangeable sodium above 15%.
Soil PH is an important parameter in terms of soil fertility. It affects the availability of plant nutrients. In addition, soil pH affects the activity of soil microorganisms. There are several soil categories based on soil pH: acidic soil and basic soil. Acidic soils have a pH of less than 7, while basic soils have a pH of more than 7. Meanwhile, neutral soils have a pH of 7. Alkaline and saline soils are two types of basic soils. The pH of saline soils ranges from 7 to 8.5, and that of alkaline soils is more than 8.5.
What are saline soils?
Saline soils contain a large amount of soluble salts. In saline soils, sodium salts usually predominate. In addition, K +, Ca2 +, Mg2 + and Cl- are responsible for soil salinity. Saline soils have a major pH range; 7 – 8.5. In saline soils, the content of exchangeable sodium is less than 15%. But its electrical conductivity is 4 or more mS/cm (millisiemens per centimeter). Soil salinity increases due to various reasons such as mineral weathering, over-irrigation, and the use of fertilizers and animal waste, etc.
Soil salinity does not promote plant growth. Thus, it negatively affects the yield. In addition, salinity also causes leaf edge necrosis, plant growth retardation, wilting and death of plants in harsh conditions. Soil restoration by leaching with good quality water is a method of reducing soil salinity. However, this can contaminate groundwater and surface water. Another agricultural solution for saline soils is the cultivation of salt tolerant crops.
What are alkaline soils?
Alkaline soils are clay soils with a pH above 8.5. High pH is due to high levels of sodium, calcium, and magnesium. In addition, hard water can also raise soil pH to alkaline levels. However, sodium carbonate is the dominant compound in alkaline soils. Sodium carbonate causes the swelling of alkaline soils.
In addition, alkaline soils have exchangeable sodium of more than 15% and electrical conductivity of less than 4 mS/cm. As with saline soils, the availability of plant nutrients in alkaline soils is low. However, some plants such as lilies, geraniums, and curly ferns grow in this soil. Some examples of highly alkaline soils are dense forests, peatlands, and soil with a lot of certain minerals.
Plants perceive alkaline soils with varying degrees of success because if there are a lot of salts, it is harmful to both trees and shrubs due to toxicity. For example, salt marshes are among the most saline soils. They have a rather sparse and sparse vegetation cover. In such an environment, there are various types of hodgepodge, as well as fancy saltwort, branched sarsazan, undersized biyurgun or salt marsh barnyard, black saxaul. There are also cute plants that can be found not only in the garden, but also in bouquets: aster saline, graceful kermek or statice (often used in bouquets as dried flowers), short-awned barley and others.
Slightly less saline soils are salt licks. Much more vegetation grows on them. Most often you can find wormwood, chamomile, kermek, kokhia and others.
What are the similarities between saline and alkaline soils?
- Both saline and alkaline soils have a pH above 7.
- In both soils, the availability of plant nutrients is low.
- Both of these soils are not conducive to plant growth.
- These soils are found in areas with little rainfall.
- Weathering of minerals also causes the appearance of both of these soils.
What is the difference between saline and alkaline soils?
The main difference between saline and alkaline soils is that the pH of saline soils ranges from 7 to 8.5, while the pH of alkaline soils is above 8.5. In addition, saline soils have less than 15% exchangeable sodium, while alkaline soils have more than 15% exchangeable sodium.
In addition, the electrical conductivity of saline soils is high, while that of alkaline soils is low. The content of organic matter in saline soils is relatively higher than in alkaline soils.
Conclusion – Saline vs. Alkaline Soils
Saline and alkaline soils are two types of soils that have basic properties. Salt soils have a pH of less than 8.5 and exchangeable sodium less than 15%, while alkaline soils have a pH of more than 8.5 and exchangeable sodium above 15%. Both of these soils do not promote proper plant growth due to the low availability of plant nutrients.