Soil acidity is one topic discussed by soil scientist nearly in all soil conferences or summits. It is becoming a big issue to our farmers especially in the northern part of the country. It is the cause of loss of mineral in the soil. It is a major cause of plant poor growth.
Soil acidity or soil acidification is the buildup of hydrogen cations, H+ which reduces the soil pH. Chemically, this happens when a proton donor gets added to the soil. Acidification also occurs when base cations such as calcium, magnesium, potassium and sodium are leached from the soil. The basic cation neutralizes the Hydrogen ion, when they are leached or eroded way from the soil by erosion or lost by other means from the soil, the Hydrogen ion build up in the soil result in soil acidity.
The following are ways of reducing soil acidity in the soil.
Adding lime to the soil is one best way of reducing soil acidity. The most commonly used liming material is agricultural limestone. The limestone is not very water-soluble, making it easy to handle. Lime or calcium carbonate’s react with an acidic soil. As lime dissolves in the soil, calcium (Ca) moves to the surface of soil particles, replacing the acidity. The acidity reacts with the carbonate (CO3) to form carbon dioxide (CO2) and water (H2O). Limestone acts as a soil acid neutralizer and consists of either calcium and magnesium carbonate or calcium carbonate.
2. AVOID HEAVY NITROGEN FERTILIZER.
Nitrogen can be added to the soil on its own but heavy nitrogenous fertilizers should be avoided as they also lead to soil acidity .example is Ammonium-N can also increase acidity through plant uptake and soil solution charge balance. Ammonium-N in fertilizers undergoes nitrification (conversion of ammonium to nitrate in soils by bacteria), hydrogen, H+ is released, which can increase acidity.
3.PLANTING OF COVER CROPS.
Erosion is one of the cause of soil acidity as it causes the washing and leaching of basic cation which neutralize acidic cation. Planting cover crops such as cowpea help to prevent erosion which in turn prevent soil acidity. When the soil surface is covered it is difficult to lose the basic mineral in the soil which neutralize the hydrogen cations.
Another way of reducing soil acidity is by applying mulching. Mulching is the cover of the soil top surface with organic materials e g straw and inorganic materials. However, the mulching materials must be decomposable. Mulches prevent the soil from leaching and erosion. When it is decomposed it add basic cation to the soil which help reduce then acidity of the soil.
5 GOOD DRAINAGE
One of the causes of soil acidity is poor drainage, poor drainage system causes erosion. Good drainage system prevent erosion which causes loss of the basic cation such as calcium Ca2+, magnesium Mg+.