With reference to agricultural soils, consider the following statements: 1. A high content of organic matter in soil drastically reduces its water holding capacity. 2. Soil does not play any role in the sulphur cycle. 3. Irrigation over a period of time c

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Q: 52 (IAS/2018)
With reference to agricultural soils, consider the following statements:
1. A high content of organic matter in soil drastically reduces its water holding capacity.
2. Soil does not play any role in the sulphur cycle.
3. Irrigation over a period of time can contribute to the salinization of some agricultural lands.
Which of the statements given above is/are correct?

question_subject: 

Geography

question_exam: 

IAS

stats: 

0,127,56,11,127,39,6

keywords: 

{'sulphur cycle': [0, 0, 0, 1], 'agricultural soils': [0, 0, 0, 2], 'soil': [7, 0, 4, 7], 'irrigation': [1, 1, 0, 2], 'salinization': [0, 0, 0, 1], 'agricultural lands': [0, 0, 0, 3], 'water holding capacity': [0, 0, 0, 1], 'organic matter': [1, 0, 0, 0]}

The statement 1 is incorrect. Quite the contrary, a high content of organic matter in soil increases its water holding capacity as organic matter can absorb water like a sponge, storing it for later use by plants. Organic matter improves the soil`s structure, porosity, and density, which all contribute to greater water-holding capacity.

The statement 2 is also incorrect. Soil plays a significant role in the sulfur cycle. Plants obtain sulfur from the soil and convert it into organic substances. When plants and animals die, the sulfur becomes part of the soil again.

The statement 3 is correct. Ongoing irrigation can indeed contribute to the salinization of some agricultural lands. This generally happens when the water used for irrigation contains salts, which accumulate in the soil over time. This can lead to a decline in soil fertility and a decrease in agricultural productivity.

Therefore, the correct answer is option 2, which states that only the 3rd statement is correct.

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