What makes the soil fertile?
- A.Overabundance of acidic materials in the soil
- B.The right mix of minerals and inorganic matter
- C.The right mix of minerals and organic matter
- D.High levels of salt in the soil
Correct answer
Explanation
The correct answer is C, the right mix of minerals and organic matter. Fertility needs mineral nutrients such as nitrogen, phosphorus and potassium from the weathered rock, and organic matter, that is humus from decayed plants and animals, which holds water, feeds soil organisms and releases nutrients slowly. Option A is wrong because an excess of acid lowers the availability of nutrients and harms root growth, which is why lime is added to strongly acidic fields. Option B is wrong because it leaves out organic matter and mentions only inorganic material; a soil of pure mineral grains, such as desert sand, is not fertile however rich its minerals. Option D is wrong because high salt content is the mark of saline or usar land, which is among the least productive soil in the country and has to be reclaimed with gypsum and drainage before it can be cropped.
Read the full article: Soils of India: Types, Distribution, Erosion and PYQs
Practice Questions
View allThe deltas of the Mahanadi and the Godavari are rich in ______ soil.
- A.black
- B.arid
- C.forest
- D.alluvial
Show answer
A delta is built out of silt that a river carries down and drops where it meets the sea, so deltaic land is alluvial by definition, and the eastern coastal deltas of the Mahanadi, Godavari, Krishna and Kaveri are among the most fertile rice tracts of the country.
Read the full explanation →Which of the following statements about black soil is INCORRECT?
- A.It is found along the Deccan trap.
- B.It is rich in phosphoric content.
- C.It has a good capacity to hold moisture.
- D.It develops deep cracks during hot weather.
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What it is rich in is calcium carbonate, magnesium, potash and lime, and remembering that short list is the safest way to answer any statement question on this soil.
Read the full explanation →Which of the following is the LEAST visible form of land erosion?
- A.Gully erosion
- B.Landslides
- C.Sheet erosion
- D.Ravine formation
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In sheet erosion water spreads over a wide slope and carries away a thin, even film of topsoil, so nothing obvious is left behind to see, and the loss is noticed only years later as falling yields.
Read the full explanation →Which of the following is NOT a method of soil conservation?
- A.Intercropping
- B.Mulching
- C.Contour Ploughing
- D.Weathering
Show answer
Weathering is the natural breaking down of rock by temperature, water, wind and living things, and it is the process that makes soil in the first place; it is not a technique that a farmer applies to save soil, so it cannot be a conservation method.
Read the full explanation →Which soil of India is best suited to the cultivation of cotton?
- A.Laterite soil
- B.Black soil
- C.Arid soil
- D.Peaty soil
Show answer
Black soil, called regur, formed from the lava of the Deccan trap and is so closely tied to this one crop that it is popularly called black cotton soil.
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