Consider the following characteristics of a soil type : 1. These soils consist of various proportions of sand, silt and clay. 2. These soils contain adequate proportions of potash, phosphoric acid and lime. 3. These soils can be further classified on the basis of their age. Identify the type of soil on the basis of the given characteristics.

The correct answer is A, Alluvial. All three features describe alluvial soil, the most widespread soil of India. Alluvial soil is deposited by rivers such as the Indus, the Ganga and the Brahmaputra, and also lines the eastern coastal deltas. Its texture changes with distance from the source, so it holds sand, silt and clay in varying proportions. It generally has enough potash, phosphoric acid and lime, which makes it ideal for sugarcane, paddy, wheat and pulses. By age it is divided into bhangar, the older alluvium on higher ground with kankar nodules, and khadar, the newer and finer alluvium of the floodplains, which is more fertile. Option B is wrong because laterite soil forms by heavy leaching in hot, wet areas and is poor in lime and potash. Option C is wrong because arid soil is sandy, saline and low in humus, found mainly in western Rajasthan. Option D is wrong because black soil is clayey regur formed from Deccan basalt and is poor in phosphoric content. Exam tip: alluvial soil by age: bhangar is old, khadar is new.