With reference to agricultural soils, consider the following statements:
- A high content of organic matter in soil drastically reduces its water holding capacity.
- Soil does not play any role in the sulphur cycle.
- Irrigation over a period of time can contribute to the salinization of some agricultural lands.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2018 Prelims]
(a) 1 and 2 only
(b) 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (b)
Explanation:
- The capacity of soil to hold water for crop utilization is known as soil water-holding capacity.
- Soil texture and organic matter are the major factors that determine this capacity.
- Sulfur is one of the three crucial nutrients that are circulated between soil, plant matter, and the atmosphere.
- Although it is predominantly present in sedimentary rocks, it is a vital component of numerous proteins that are necessary for living organisms.
- Sulphur is released by the erosion of rocks and minerals.
- The excessive presence of salts in soil is a significant issue for agriculture under irrigation.
- Long-term irrigation can lead to the accumulation of salts in the soil, causing damage to crops, which is known as soil salinization.
Therefore, option (b) is the correct answer.