Red soil is a kind of soil with reddish tan color, which is composed of silt, sand, clay and some organic matter. Due to iron oxide content in the soil, it has got its red color. It is also known as laterite or ferralitic soil.
These soils occur in areas with alternate wet and dry periods. Red soils are found in warm, moist areas wherever precipitation is greater than 500 mm in a year and occur mostly in the tropical belt. The tropical rainforest, tropical savannas, monsoon and warm temperate areas, piedmonts and isolated hills favour the formation of red soil. It constitutes the main soil type in the bulk of South India, Maharashtra and Chhattisgarh.
Red soil is mostly composed of quartz, kaolinite, and mica. The soil properties vary depending upon the horizon and degree of leaching. Red soils have weak fragile structures with low water retention capacity, low nitrogen and calcium and poor in organic matter.
The red soil is well suited for cultivation of dry crops, such as pulses, sorghum, maize, and millets; it is not suitable for irrigated and wetland crops. The soil supports good cultivation of cotton, storage crops, oilseeds, castor, and tobacco. Since the red soil is deficient in nitrogen, phosphorus, and potassium, it needs additional nutrient to support agricultural productivity.
The main attribute of the red soil is aluminum and iron content which provide red color to the soil. The presence of aluminum gives a sour taste to the soil and this presence restricts the aeration of the soil. It makes the acidic in nature and due to its acidic nature with low moisture, plant growth can be low as these soils have low level of nutrients that support the growth of plants.
Red soil is subjected to serious problems because of over cultivation and deforestation. The most significant problems related to these soils are its low water holding capacity, erosion, and leaching of essential elements. Techniques such as addition of organic matter, use of mulch to reduce the rate of infiltration of rain water, and use of improved varieties of crops are some of the common practices to reduce soil erosion and enhance its structure and productivity.
Similarly, manure, compost, and green manures can increase the fertility of the soil and also reduce soil erosion. To increase the fertility of red soil farmers also use a variety of organic and inorganic fertilizers to provide the necessary nutrients. The application of gypsum and liming materials to reduce the acidity and also enhance the soil structure can be beneficial.
In conclusion, red soil has an important place in agricultural production. However, the wide range of problems associated with its use call for the adoption of proper sustainable management practices to maintain its fertility, water holding capacity and biological activity. This in turn can support the sustainable use of these soils for agricultural production in a better way.
