Which one of the following is correct?
[amp_mcq option1=”In humid tropical region, humus content is high in soil” option2=”Glacial till exhibits deep horizon” option3=”Humus accumulates in cold climate” option4=”In equatorial climates, humus content is high in soil” correct=”option3″]
This question was previously asked in
UPSC Geoscientist – 2022
– B) Glacial till is unconsolidated glacial sediment and serves as a parent material for soil development. While soils *can* develop on till, the till itself doesn’t “exhibit deep horizons”; soil horizons (A, B, C) develop *within* the soil profile over time through pedogenic processes. Glacial action often mixes material rather than creating distinct deep horizons in the till layer itself. (Incorrect)
– C) In cold climates, low temperatures significantly slow down the rate of decomposition of organic matter by microorganisms. This leads to the accumulation of undecomposed or partially decomposed organic matter, forming a thicker layer of humus (or organic horizons like O horizon) on or in the soil. (Correct)
– D) Equatorial climates are humid tropical regions with rapid decomposition, leading to low humus content. (Incorrect, same reason as A).
– Cold climates slow down decomposition, promoting humus accumulation.
– Warm, humid climates accelerate decomposition, limiting humus accumulation.