Question 63
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?
AOptions
BSolution
Let's evaluate the given statements about tropical rainforest soils:
Statement-I: The soil in tropical rain forests is rich in nutrients. This statement is incorrect. Despite the lush vegetation, the soils in tropical rainforests (such as Oxisols and Ultisols) are typically poor in nutrients. The high rainfall leads to rapid leaching of soluble nutrients from the soil. Most of the nutrients in a rainforest ecosystem are locked up in the living biomass (plants and animals) and the layer of decomposing organic matter on the forest floor, rather than being stored in the soil itself.
Statement-II: The high temperature and moisture of tropical rain forests cause dead organic matter in the soil to decompose quickly. This statement is correct. The warm, humid conditions prevalent in tropical rainforests provide an ideal environment for decomposers like bacteria, fungi, and insects to rapidly break down dead organic matter (leaves, branches, dead animals). This quick decomposition means that nutrients are rapidly recycled back into the living vegetation, preventing their accumulation in the soil.
Therefore, Statement-I is incorrect, and Statement-II is correct.
CStrategy
For ecology and biogeography questions, understand the interrelationships between climate, vegetation, and soil characteristics. Be aware of common misconceptions, such as assuming that lush vegetation implies rich soil. Focus on the processes (like leaching and decomposition) that influence nutrient cycling in different biomes.
DSyllabus Analysis
This question falls under 'Environment and Ecology - Biomes and Ecosystems' and 'Physical Geography - Biogeography' in the UPSC Prelims syllabus, focusing on soil characteristics of tropical rainforests.
EQuestion Analysis
Easy to Medium. This is a common concept taught in environmental geography. The rapid decomposition and poor soil nutrient content are characteristic features of tropical rainforests.