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Management or Amelioration of soil acidity
Lime requirement (LR): Is defined as the amount of liming material that must be added to raise the pH to some desired value (pH 6.0 to 7.0). There are a number of liming materials available in the market and may be used according to their availability, convenience and economy. Some of the important liming materials are;
2. Lime hydroxide {Ca (OH)2}- hydrated lime or slaked lime. Caustic in nature and difficult to handle. 3. Lime carbonate (CaCO3)- ground lime stone occurs as Boglime or marl, Calcite, Oysters shells and precipitate carbonates. It is most commonly used and it is largely sold in the market as pulverized or ground lime stone, called agriculture lime. 4. Basic slag: Byproduct of Iron industry. 5. Dolomite (CaMgCO3) Liming reaction in soils
H+ [Soil] + CaCO3 ------- Ca2+ [Soil) + CO2 + H2O or CaCO3+H2CO3 -------Ca (HCO3)2 H+ [Soil] + Ca(HCO3)2-------- [Soil ]Ca2+ + 2 H2O + 2CO2 Benefits of liming on acidic soils
b. It eliminates major problems of Fe, Al, Mn and H toxicities.
b. The raised pH also reduces excess soluble Mn and Fe by forming insoluble hydroxides. 4. It makes K+ more efficient in plant nutrition. 5. It increases the availability of N by creating a more favorable environment for microbes. 6. Bacterial activity is enhanced and help in control of certain plant pathogens like club rot disease of cole crops. |
Last modified: Wednesday, 7 December 2011, 5:13 AM