How to manage Alkaline soil in Best 6 Ways

How to manage Alkaline soil

Table of Contents

Alkaline Soil

These soil which contains appreciable quantities of exchangeable sodium and may or may not contain excess soluble salts are known as alkali soil.

Characteristics of Alkaline soil

 In dry season, a layer of black crush is formed over the surface. so it is called black alkali.

 Electrical conductivity (EC) 4 mmhos/cm.

 PH is 8.5 10.

 Exchangeable Sodium Percentage (ESP) is 15.

Classification of Alkali soil

There are 3 types

1. Saline alkali soil when they contain soluble salts in excess, they are known as saline alkali soil.

2. NonSaline alkali soil when they do not contain soluble salts are called non saline alkali soil.

3. Degraded alkali soil Under certain circumstances, the clay complex of some alkali soil is broker down to give rise to degraded alkaline soil.

How to manage Alkaline soil/Management of Alkali soil

A. Chemical Method

1. Application of Gypsum- By cationic exchange, calcium is often used to replace sodium in alkali soil. If the soil has no reserve Calcium carbonate, the addition of gypsum is necessary. When gypsum is used as reclaiming agent, Calcium replace the exchangeable sodium and converts the clay back into calcium clay.

Na₂CO₃ + CaSO₄ → CaCO₃+ Na₂SO₄

Use of Sulphur- If the alkaline soil contain free calcium carbonates, sulphuric acid application is effective for reclaiming the soil. When sulphur is spread on the soil, it is oxidized to sulphuric acid, which converts sodium sulphate. If calcium carbonate is not present in the soil, it should be added artificially when sulphur is used for reclamation.

2S + 2H₂O + 3O₂ → 2H₂SO₄

Na₂CO₃ + H₂SO₄→ CO₂ + H₂O + Na₂SO₄↓

2CaCO₃ + H₂SO₄→ CaSO₄ + Ca(HCO₃)₂

Addition of organic matter- The addition of organic matter increases acidity thus helping in lowering the soil pH. Use of sulphuric acid Sulphuric acid changes to sodium carbonates to the less harmful sulphate and reduce the alkalinity of soil.

Na₂CO₃ + H₂SO₄→ CO₂ + H₂O + Na₂SO₄↓

Addition of molasses- Addition of molasses in the soil provide the source of energy for micro organism which on fermentation produce organic acid. The organic acid reduce alkalinity.

B. Cultural Method

1. Providing proper drainage- If the soil is not free draining, artificial drains are open to wash out the alkalinity of soil.

2. Proper use of irrigation water- If the amount of water in the soil is decrease the concentration of alkalinity in the soil solution is increase. Thus moisture should be kept at optimum field capacity.

3. Use of acidic fertilizer- Acidic nature of fertilizer should be used.

4. Use of organic manures- Organic manure have high water holding capacity. When sufficient amount of organic manure are added the water holding capacity of soil are increases. As a result, the conductivity of the soil solution decreases.

5. Ploughing and levelling of land- Ploughing and levelling increases the infiltration and percolation rate of the land. Thus alkalinity leach down to the lower level.

6. Retardation of water evaporation from soil surface- Water may be conserved in the soil by retarding the water evaporation.

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