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Q53 (IAS/2022) Environment & Ecology › Ecology & Ecosystem Basics › Wetland ecosystems Official Key

"If rainforests and tropical forests are the lungs of the Earth, then surely wetlands function as its kidneys." Which one of the following functions of wetlands best reflects the above statement?

Result
Your answer: —  ·  Correct: D
Explanation

The correct answer is Option 4. The analogy compares wetlands to kidneys because of their natural filtration and purification capabilities.

Just as biological kidneys filter waste and toxins from the bloodstream, wetlands act as huge biological filters for ecosystems. This function is primarily driven by aquatic plants (hydrophytes) and microorganisms that:

  • Absorb heavy metals: Plants like water hyacinths can sequester toxic pollutants.
  • Remove excess nutrients: They trap nitrogen and phosphorus from agricultural runoff, preventing eutrophication in larger water bodies.
  • Break down organic waste: Microbes in the wetland soil decompose organic matter, effectively "cleaning" the water.

While Options 1, 2, and 3 describe essential ecological functions (hydrology, food webs, and erosion control), they do not specifically address the purification/filtration aspect implied by the "kidney" metaphor. Option 4 directly explains how wetlands chemically and biologically cleanse the environment, making it the most accurate reflection of the statement.

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Don’t just practise – reverse-engineer the question. This panel shows where this PYQ came from (books / web), how the examiner broke it into hidden statements, and which nearby micro-concepts you were supposed to learn from it. Treat it like an autopsy of the question: what might have triggered it, which exact lines in the book matter, and what linked ideas you should carry forward to future questions.
Q. "If rainforests and tropical forests are the lungs of the Earth, then surely wetlands function as its kidneys." Which one of the followin…
At a glance
Origin: From standard books Fairness: High fairness Books / CA: 10/10 · 0/10

This is a classic 'Functional Analogy' question found in the intro chapters of Shankar IAS or Majid Hussain. The strategy is simple: Don't just memorize definitions; map ecosystem functions to biological organs (Lungs = Gas Exchange, Kidneys = Filtration/Detox). If you missed this, you ignored the 'Ecosystem Services' table in your standard text.

How this question is built

This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.

Statement 1
Do wetlands' water cycles involve surface runoff, subsoil percolation, and evaporation?
Origin: Direct from books Fairness: Straightforward Book-answerable
From standard books
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > hydrological cyclE. > p. 24
Presence: 5/5
“Te hydrological cycle is an intricate combination of evaporation, transpiration, air-mass movements, condensation, precipitation, run of, percolation, and groundwater movements. Te greater part of atmospheric moisture, which eventually falls to the Earth as precipitation (rains), comes from the oceans. Some water takes a short cut in the water cycle and enters air (atmosphere) directly through evaporation and transpiration (from soil and vegetation) without returning to the oceans. Te process of evaporation, condensation and precipitation are essentially climatic and their functions in the water cycle would be quite simple if it were not for the constant motion in the atmosphere. Tis requires heat as well as moisture.”
Why this source?
  • Explicitly lists evaporation, runoff and percolation as constituent processes of the hydrological cycle.
  • Frames these processes as part of water movement on and in the Earth's surface, which applies to standing waterbodies.
Science-Class VII . NCERT(Revised ed 2025) > Chapter 7: Heat Transfer in Nature > Fig. 7.9: Water cycle > p. 98
Presence: 5/5
“The continuous movement of water — upward as water vapour and downward through precipitation, passing through soil, rocks, and plants, and fi nally returning to water bodies, is called water cycle (Fig. 7.9). Thus, the water cycle helps in redistributing and replenishing water in rivers, lakes, and oceans. It also serves to conserve the total amount of water on the Earth. Rainwater that falls on the surface of the Earth, fl ows into ponds, lakes, rivers, and oceans or seeps into the ground.”
Why this source?
  • Describes rainwater flowing into ponds and lakes or seeping into the ground and returning to the atmosphere as vapour.
  • Directly links surface inflow, subsurface seepage and evaporation for small waterbodies analogous to wetlands.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Wetland Ecosystem > p. 27
Presence: 4/5
“Land areas of poor surface drainage, such as marshes and swamps are known as wetlands. Te wetland ecosystems experience periodic fooding from the adjacent deepwater habitat, and therefore supports plants and animals specifcally adapted to such shallow fooding or water logging. Wetlands are shallow lakes, generally less than three meters in depth. Wetlands include lake littorals (marginal areas between the highest and the lowest water level of the lakes), foodplains, bogs, fens, peat-land, marshy and swampy areas.”
Why this source?
  • Defines wetlands as shallow lakes and areas of poor surface drainage subject to periodic flooding and waterlogging.
  • Identifies wetlands as shallow waterbodies where hydrological processes (surface flow, percolation and evaporation) will operate.
Statement 2
Do algae form the primary nutrient base of wetland food webs that support fish, crustaceans, molluscs, birds, reptiles, and mammals?
Origin: Direct from books Fairness: Straightforward Book-answerable
From standard books
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 14: Marine Organisms > The food web > p. 208
Presence: 5/5
“rti7 ;It r Phytoplanktons are the foundation of the aquatic food web, the primary producers; they feed everything from microscopic animal-like zooplankton to whales. Small fish and invertebrates graze on the phytoplanktons, and then those smaller animals are eaten by bigger ones.”
Why this source?
  • Explicitly identifies phytoplankton as the foundation (primary producers) of the aquatic food web.
  • States phytoplankton feed organisms ranging from zooplankton to large consumers, linking primary production to higher trophic levels including fish and invertebrates.
Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 30: Climatic Regions > Geographical advantage > p. 465
Presence: 5/5
“• Phytoplankton, algae and other plants (primary producers) are able to photosynthesise to produce organic material from inorganic nutrients. And the organic material forms the building block for all animals higher up in the marine food chain.• Almost all biomass in the ocean is derived from the phytoplankton and to a lesser extent the benthic algae (found on the bottom of a sea or lake; algae are insignificant players in the marine ecosystem compared to the phytoplankton as they only inhabit a narrow zone around the coast). Hence phytoplankton are called the grass of the sea.• There is a fundamental problem that phytoplankton in the open ocean face.”
Why this source?
  • Describes phytoplankton and algae as primary producers that produce organic material forming the building blocks for animals higher up the food chain.
  • Emphasizes that almost all marine biomass is derived from phytoplankton, underscoring their central role in aquatic productivity.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Social Relevance of Wetlands > p. 27
Presence: 4/5
“Wetlands have great signifcance for humanity and ecology. Some of the important benefts from the wetlands are: (i) they are the habitats of aquatic plants, animals, birds including the migratory species, (ii) areas where sediments and nutrients are fltered from the surface water, (iii) they help in the purifcation of water, (iv) they mitigate foods, (v) help in the recharge of underground watertable, (vi) provide drinking water, fsh, fodder and fuel, (vii) help in maintaining biodiversity, and (viii) promote tourism and ecotourism. Te wetlands are however, depleting at a faster pace. Te main causes of depletion of wetlands are: (i) rapid growth of population, (ii) encroachment of agriculture on wetlands, (iii) over-grazing, (iv) aquaculture, (v) reclamation, (vi) water-pollution, (vii) dumping grounds for industrial and domestic waste.”
Why this source?
  • States wetlands are habitats of aquatic plants and support fish and other fauna, linking wetland ecosystems to aquatic primary producers.
  • Notes wetlands filter sediments and nutrients and help maintain biodiversity, providing the environmental context where algae-driven food webs operate.
Statement 3
Do wetlands play a vital role in maintaining sedimentation balance and soil stabilization?
Origin: Direct from books Fairness: Straightforward Book-answerable
From standard books
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.8.2. Role of mangroves > p. 48
Presence: 5/5
“• Mangrove plants have (additional) special roots such as prop roots, pneumatophores which help to impede water flow and thereby enhance the deposition of sediment in areas (where it is already occurring), stabilize the coastal shores, provide breeding ground for fishes. • Mangroves moderate monsoonal tidal floods and reduce inundation of coastal lowlands. • It prevents coastal soil erosion. • It protects coastal lands from tsunami, hurricanes and floods Fine, anoxic sediments deposited under mangroves act as sinks for a variety of heavy (trace) metals which are scavenged from the overlying seawater by colloidal particles in the sediments. By cleaning our air, they take in carbon dioxide, storing the carbon in their roots, leaves, branches and in its surrounding silt, and release oxygen back to the atmosphere, along with a little methane gas.”
Why this source?
  • Describes mangrove root structures (prop roots, pneumatophores) that impede water flow and thereby enhance sediment deposition.
  • Explicitly states mangroves stabilize coastal shores and prevent coastal soil erosion, linking wetlands to soil stabilization.
  • Notes moderation of tidal/monsoonal floods, which affects sediment transport and deposition patterns.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Social Relevance of Wetlands > p. 27
Presence: 4/5
“Wetlands have great signifcance for humanity and ecology. Some of the important benefts from the wetlands are: (i) they are the habitats of aquatic plants, animals, birds including the migratory species, (ii) areas where sediments and nutrients are fltered from the surface water, (iii) they help in the purifcation of water, (iv) they mitigate foods, (v) help in the recharge of underground watertable, (vi) provide drinking water, fsh, fodder and fuel, (vii) help in maintaining biodiversity, and (viii) promote tourism and ecotourism. Te wetlands are however, depleting at a faster pace. Te main causes of depletion of wetlands are: (i) rapid growth of population, (ii) encroachment of agriculture on wetlands, (iii) over-grazing, (iv) aquaculture, (v) reclamation, (vi) water-pollution, (vii) dumping grounds for industrial and domestic waste.”
Why this source?
  • Identifies wetlands as areas where sediments and nutrients are filtered from surface water, directly linking them to sediment balance.
  • Links sediment filtering to water purification and ecosystem services that help maintain soil and water quality.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > MAngrove (forests). > p. 49
Presence: 4/5
“Mangroves are the distinctive ecosystems found along the shallow coasts 30o N or S and the equator. Mangroves are found in tidal fats, estuaries and muddy coasts in tropical and subtropical areas. Communities of mangroves, termed mangals, play an important role on many tropical coasts. Tey are highly productive ecosystems which are capable of exporting energy and materials to adjacent communities. Tey support a diverse heterotrophic food chain, act as nurseries in the life cycle of some organisms, and ofer some protection against coastal erosion and storm surge attack. At present, like many types of wetland, they are under severe anthropogenic pressures.”
Why this source?
  • States mangroves offer protection against coastal erosion and storm surge, showing a role in stabilizing coastal soils.
  • Describes mangroves as productive ecosystems that provide physical protection to adjacent lands, reinforcing their stabilizing function.
Statement 4
Do aquatic plants in wetlands absorb heavy metals and excess nutrients?
Origin: Direct from books Fairness: Straightforward Book-answerable
From standard books
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Social Relevance of Wetlands > p. 27
Presence: 5/5
“Wetlands have great signifcance for humanity and ecology. Some of the important benefts from the wetlands are: (i) they are the habitats of aquatic plants, animals, birds including the migratory species, (ii) areas where sediments and nutrients are fltered from the surface water, (iii) they help in the purifcation of water, (iv) they mitigate foods, (v) help in the recharge of underground watertable, (vi) provide drinking water, fsh, fodder and fuel, (vii) help in maintaining biodiversity, and (viii) promote tourism and ecotourism. Te wetlands are however, depleting at a faster pace. Te main causes of depletion of wetlands are: (i) rapid growth of population, (ii) encroachment of agriculture on wetlands, (iii) over-grazing, (iv) aquaculture, (v) reclamation, (vi) water-pollution, (vii) dumping grounds for industrial and domestic waste.”
Why this source?
  • Explicitly identifies wetlands as areas where sediments and nutrients are filtered from surface water.
  • Links wetland function to water purification, implying removal/uptake of excess nutrients by the wetland system.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.8.2. Role of mangroves > p. 48
Presence: 4/5
“• Mangrove plants have (additional) special roots such as prop roots, pneumatophores which help to impede water flow and thereby enhance the deposition of sediment in areas (where it is already occurring), stabilize the coastal shores, provide breeding ground for fishes. • Mangroves moderate monsoonal tidal floods and reduce inundation of coastal lowlands. • It prevents coastal soil erosion. • It protects coastal lands from tsunami, hurricanes and floods Fine, anoxic sediments deposited under mangroves act as sinks for a variety of heavy (trace) metals which are scavenged from the overlying seawater by colloidal particles in the sediments. By cleaning our air, they take in carbon dioxide, storing the carbon in their roots, leaves, branches and in its surrounding silt, and release oxygen back to the atmosphere, along with a little methane gas.”
Why this source?
  • Describes how mangrove roots slow water flow and enhance sediment deposition.
  • States fine anoxic sediments under mangroves act as sinks for a variety of heavy (trace) metals.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Lake ecosystem > p. 26
Presence: 3/5
“Te lakes generally receive their water from the surface runof. In the long run the lakes receives enormous quantities of nutrients (phosphate and nitrate) from the adjacent areas and human activities. Tese nutrients promote the growth of algae, aquatic plants and diferent types of fauna. Tis process of growth of weeds and plants in waterbodies is known as eutrophication.”
Why this source?
  • Notes lakes receive phosphate and nitrate that promote growth of algae and aquatic plants.
  • Implies aquatic plants incorporate available nutrients as they proliferate (linking nutrient enrichment to plant uptake).
Pattern takeaway: UPSC is moving from 'What is X?' to 'Why is X called Y?'. They test your ability to understand ecological functions through analogies. Future questions might ask about 'Ecosystem Engineers' (Beavers/Corals) or 'Keystone Species' using similar functional logic.
How you should have studied
  1. [THE VERDICT]: Sitter. Direct hit from Shankar IAS (Chapter on Aquatic Ecosystems) or Majid Hussain. The phrase 'Wetlands are the kidneys of the landscape' is a standard subheading.
  2. [THE CONCEPTUAL TRIGGER]: Ecosystem Services (Regulating Services). Specifically, the distinction between physical regulation (flood control) and chemical regulation (water purification).
  3. [THE HORIZONTAL EXPANSION]: Memorize these Functional Metaphors: 1. Rainforests = Lungs (Carbon/Oxygen cycle). 2. Coral Reefs = Rainforests of the Sea (Biodiversity). 3. Mangroves = Coastal Shock Absorbers (Physical barrier). 4. Wetlands = Biological Supermarkets (Food webs) AND Kidneys (Filtration). 5. Soil = Earth's Stomach (Decomposition/Nutrient Cycling).
  4. [THE STRATEGIC METACOGNITION]: Apply 'Organ Logic'. What does a kidney do? It filters blood and removes toxins. Look for the option describing filtration or toxin removal. Option A is Circulation (Heart). Option B is Digestion/Energy (Stomach). Option C is Structural Support (Skeleton). Option D is Filtration (Kidney). Match the function.
Concept hooks from this question
📌 Adjacent topic to master
S1
👉 Hydrological cycle components (evaporation, runoff, percolation)
💡 The insight

Evaporation, surface runoff and subsurface percolation are core processes that move water through and out of wetlands.

High-yield for geography and environment questions because these processes explain water redistribution and wetland functioning; connects to topics on water balance, watershed behaviour and ecosystem services; enables answers on causes of flooding, groundwater recharge and evaporative loss in wetland contexts.

📚 Reading List :
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > hydrological cyclE. > p. 24
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > hydrological cyclE. > p. 23
  • Science-Class VII . NCERT(Revised ed 2025) > Chapter 7: Heat Transfer in Nature > Fig. 7.9: Water cycle > p. 98
🔗 Anchor: "Do wetlands' water cycles involve surface runoff, subsoil percolation, and evapo..."
📌 Adjacent topic to master
S1
👉 Wetlands as shallow, poorly drained waterbodies
💡 The insight

Wetlands are shallow lakes and poorly drained areas, which determines how water is stored, flooded and released via runoff, seepage and evaporation.

Important for questions on ecosystem types, landform–hydrology interaction and habitat adaptation; links physical geography with ecology and resource management; useful for framing answers on conservation, flood mitigation and wetland services.

📚 Reading List :
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Wetland Ecosystem > p. 27
🔗 Anchor: "Do wetlands' water cycles involve surface runoff, subsoil percolation, and evapo..."
📌 Adjacent topic to master
S1
👉 Surface vs subsurface flow and climatic control
💡 The insight

Whether precipitation becomes surface runoff or percolates into the ground depends on climate and substrate, shaping wetland water balance.

Critical for explaining spatial variation in groundwater recharge, runoff generation and evaporation rates; ties into topics on climate variability, soil/rock permeability and water resource assessment; helps answer comparative questions on humid vs arid responses and management measures.

📚 Reading List :
  • Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 4: Weathering, Mass Movement and Groundwater > Groundwater > p. 41
  • FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 12: Water (Oceans) > HYDROLOGICAL CYCLE > p. 101
🔗 Anchor: "Do wetlands' water cycles involve surface runoff, subsoil percolation, and evapo..."
📌 Adjacent topic to master
S2
👉 Phytoplankton and algae as primary producers
💡 The insight

Phytoplankton and algae form the base of aquatic food webs by photosynthetically producing organic matter that fuels higher trophic levels.

High-yield ecology topic often tested in questions on productivity, food chains, and fisheries; links to topics like primary productivity, nutrient cycling, and human impacts (e.g., eutrophication). Understanding this helps answer questions on ecosystem functioning, fishery resources, and conservation.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 14: Marine Organisms > The food web > p. 208
  • Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 30: Climatic Regions > Geographical advantage > p. 465
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Decomposers or Saprophytes > p. 31
🔗 Anchor: "Do algae form the primary nutrient base of wetland food webs that support fish, ..."
📌 Adjacent topic to master
S2
👉 Plankton-mediated energy transfer (phyto → zoo → higher consumers)
💡 The insight

Zooplankton graze on phytoplankton and transfer energy and organic matter to fishes and other consumers, forming the core trophic pathway in aquatic systems.

Useful for questions on trophic dynamics, nursery habitats (e.g., mangroves), and factors controlling fish stocks; connects to fisheries management, food web disruptions, and ecosystem services.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 14: Marine Organisms > 14.3. ZOOPLANKTON > p. 209
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > i) Grazing food chain > p. 12
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > iii) Planktoni > p. 33
🔗 Anchor: "Do algae form the primary nutrient base of wetland food webs that support fish, ..."
📌 Adjacent topic to master
S2
👉 Wetlands as nutrient and biodiversity hubs
💡 The insight

Wetlands host aquatic plants and filter nutrients, creating conditions that support diverse fauna including fish, birds, and mammals dependent on primary production.

Relevant for policy and conservation questions on wetland protection, ecosystem services, and impacts of eutrophication; links ecology with water management, biodiversity, and livelihoods (fisheries, tourism).

📚 Reading List :
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Social Relevance of Wetlands > p. 27
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.3. EUTROPHICATION > p. 36
🔗 Anchor: "Do algae form the primary nutrient base of wetland food webs that support fish, ..."
📌 Adjacent topic to master
S3
👉 Mangrove-mediated sediment deposition & shoreline stabilization
💡 The insight

Mangrove root structures impede water flow, enhancing sediment deposition and stabilizing coastal soils.

High-yield: explains mechanisms of coastal erosion control and ecosystem-based disaster risk reduction; links to coastal ecology, Ramsar/wetland policy, and climate adaptation. Mastery helps answer questions on shoreline protection, mangrove restoration, and nature-based solutions.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.8.2. Role of mangroves > p. 48
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > MAngrove (forests). > p. 49
🔗 Anchor: "Do wetlands play a vital role in maintaining sedimentation balance and soil stab..."
🌑 The Hidden Trap

Since they asked about 'Kidneys' (Filtration), the next logical question is about the specific agents of this filtration. Prepare 'Phytoremediation': Water Hyacinth (Eichhornia) absorbs Cadmium/Lead; Pteris vittata absorbs Arsenic; Mustard plants absorb heavy metals. Also, 'Constructed Wetlands' are now a policy focus for sewage treatment (Swachh Bharat 2.0).

⚡ Elimination Cheat Code

Use the 'Biological Mapping' Hack. The question uses a biological metaphor ('Kidneys').
1. Kidneys = Filter waste/toxins.
2. Scan options for 'Waste', 'Toxins', or 'Purification'.
3. Option A (Water Cycle) = Circulation.
4. Option B (Algae/Food) = Nutrition.
5. Option C (Soil/Sediment) = Physical Structure.
6. Option D (Absorb metals/nutrients) = Detoxification.
Only D matches the biological function of a kidney.

🔗 Mains Connection

Link this to GS3 (Pollution) & GS2 (Health). Wetland destruction = Kidney failure of the ecosystem. This leads to 'Bioaccumulation' of heavy metals in fish -> Humans eat fish -> Minamata Disease (Mercury) or Itai-Itai (Cadmium). Wetland conservation is actually preventative healthcare policy.

✓ Thank you! We'll review this.

SIMILAR QUESTIONS

CAPF · 2021 · Q84 Relevance score: -2.49

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.

IAS · 2003 · Q110 Relevance score: -3.58

Assertion (A) : Unlike temperate forests, the tropical rain forests, if cleared, can yield productive farm-land that can support intensive agriculture for several years even without chemical fertilizers. Reason (R) : The primary productivity of the tropical rain forest is very high when compared to that of the temperature forests.

NDA-I · 2015 · Q50 Relevance score: -3.92

The luxuriant growth of natural vegeta- tion in tropical rainforest is due to 1. fertile soil. 2. hot and wet climate throughout the year. 3. intense sunlight for photosynthesis. 4. seasonal change to facilitate nutrient absorption. Select the correct answer using the code given below :

IAS · 2011 · Q23 Relevance score: -4.09

If a tropical rain forest is removed, it does not regenerate quickly as compared to a tropical deciduous forest this is because.

IAS · 1996 · Q49 Relevance score: -4.21

Assertion (A) : Mangroves are very specialised forest ecosystems of tropical and subtropical regions bordering certain sea coasts. Reason (R) : They stabilise the shoreline and act as bulwark against encroachments by sea. In the context of the above two statements, which one of the following is correct ?