Influence of lime on soil properties in relation to plant nutrition

Direct benefits

• Toxicity of Al3+ and Mn2+ is reduced

• Reduced uptake of Ca2+ and Mg2+ in the soil solution can be alleviated

• Removal of H+ ion toxicity.

Indirect benefits

• The application of liming materials in acid soils will inactivate the iron and aluminium, thus increase the available P

• The toxicity of most of the micronutrients (Fe, Mn, Cu, Zn) can be prevented by the application of lime

• Most of the organisms responsible for the conversion of ammonia to nitrates (NH3NO3) require large amounts of active calcium. As a result nitrification is enhanced by liming to a pH of 5.5–6.5

• The process of N fixation both by symbiotic and non-symbiotic is favoured by liming

• The structures of fine textured soil can be improved by liming

• The amelioration of soil acidity by liming may have a significant role in the control of plant pathogens, e.g., Club root disease of Cole crops can be reduced by liming

• Liming increases the efficiency of different fertilizers especially N and P fertilizers.

Over liming

If liming materials are applied over and above its requirement then it is called over liming.

Effects of over liming

When excessively large amounts of lime are applied to an acidic soil, the growth of plants is affected by influencing either one or many of these following:

• Deficiency of iron, copper and zinc will occur

• P and K availability will be reduced

• Due to high OH ion concentration by over liming, root development will be inhibited

• Boron deficiency will occur

• The incidence of diseases like scab in root crops will be increased