Prelims 2023 · Q63
Easyनिम्नलिखित कथनों पर विचार कीजिए :
- कथन–I: उष्णकटिबंधीय वर्षावनों की मृदा पोषक तत्त्वों से भरपूर होती है।
- कथन–II: उष्णकटिबंधीय वर्षावनों के उच्च ताप और आर्द्रता के कारण मृदा में विद्यमान मृत जैव पदार्थ का द्रुत अपघटन होता है।
उपर्युक्त कथनों के बारे में, निम्नलिखित में से कौन-सा एक सही है?
Read this question in English
Consider the following statements:
Statement-I. The soil in tropical rain forests is rich in nutrients.
Statement-II. The high temperature and moisture of tropical rain forests cause dead organic matter in the soil to decompose quickly.
Which one of the following is correct in respect of the above statements?
(a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I · (b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I · (c) Statement-I is correct but Statement-II is incorrect · (d) Statement-I is incorrect but Statement-II is correct
उत्तर और व्याख्या · explanation in English
Answer: (d) कथन–I गलत है किन्तु कथन–II सही है
The soil of a tropical rain forest is poor, not rich, in nutrients. Heat and moisture make bacterial action intense, so dead plant matter is oxidised quickly and very little humus builds up in the soil; heavy rain also leaches nutrients out of tropical soils.
- ✗ Statement-I Fast decay leaves the soil with very low humus content, and heavy rain leaches away nutrients; lateritic soils of heavy-rain tropical areas are generally deficient in plant nutrients.
- ✓ Statement-II In humid tropical and equatorial climates bacterial growth and action is intense, so dead vegetation is rapidly oxidised. This is the reason the humus content of the soil stays low, not a sign of richness.
Remember · Fast decay plus heavy rain leave tropical rain forest soil low in humus and nutrients; in cold climates decay is slow, so humus and peat accumulate.
📘 Read it in NCERT: Class 11 Fundamentals of Physical Geography, Ch 5 (practise this chapter) · Class 10 Contemporary India – II, Ch 1 (practise this chapter)
Sources
- NCERT Class 11 · Fundamentals of Physical Geography, Chapter 5 “In humid tropical and equatorial climates, bacterial growth and action is intense and dead vegetation is rapidly oxidised leaving very low humus content in the soil.”
- NCERT Class 10 · Contemporary India – II, Chapter 1 “This soil is the result of intense leaching due to heavy rain. Lateritic soils are mostly deep to very deep, acidic (pH<6.0), generally deficient in plant nutrients”
Question and answer: UPSC's official GS Paper I (2023, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·