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Which of the following statements about tropical rainforests are correct? 1. The soils of tropical rainforests are ite infertile. 2. The vegetation is evergreen, enabling photosynthesis to take place year around. 3. They have been described as 'deserts covered by trees'. 4. They are the most productive land-based ecosystem. Select the correct answer using the code given below.
Explanation
Tropical rainforests are characterized by highly weathered, acidic, and nutrient-poor soils, primarily Oxisols and Ultisols [1]. Despite the lush vegetation, the soil is infertile because heavy rainfall causes intense leaching, and nutrients are rapidly recycled into biomass rather than stored in the soil [2]. This paradox leads to the description of these forests as 'deserts covered by trees'—a system where the soil itself cannot support agriculture once the biomass is removed. The vegetation is evergreen, with a year-round growing season that allows continuous photosynthesis due to uniform high temperatures and moisture [3]. Furthermore, tropical rainforests are the most productive land-based ecosystems, contributing approximately one-third of the Earth's total terrestrial net primary productivity (NPP) [3]. All four statements are scientifically accurate descriptions of this biome's ecological and pedological characteristics.
Sources
- [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 3: Terrestrial Ecosystems > 3.2.5. Tropical rain forests: > p. 25
- [2] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > 1. Tropical Evergreen Rainforest Biome > p. 5
- [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 30: Climatic Regions > Equatorial Vegetation > p. 426