India’s Forests May Double Carbon Storage by 2100: Environmental Research: Climate

Source: TH

Context:

The study published in Environmental Research: Climate provides a forward-looking perspective on India’s environmental landscape, suggesting that while global emissions are a threat, they may trigger a biological growth response in Indian forests.

Summary

• The Projection: India’s forest vegetation carbon stock could increase by 35% to 97% by the year 2100.
• The Paradox: Counter-intuitively, the highest carbon gains are expected under high-emission scenarios due to intensified environmental drivers.
• Key Drivers: Growth is fueled by “CO₂ Fertilization” (higher CO₂ levels boosting photosynthesis) and increased rainfall projections.
• Geographic Winners: Dry and semi-arid regions (Rajasthan, Gujarat) are projected to see the highest relative growth (over 60%).
• The Warning: Increased biomass does not necessarily mean a “safer” climate; it raises the risk of “Carbon Bombs” where stored carbon is released rapidly via wildfires or pests.

Background Concept

To understand how forests act as a “climate sponge,” it is essential to look at the biological process of carbon storage and the factors that accelerate it.

1. What is Vegetation Carbon Stock?

Carbon stock refers to the amount of carbon stored in the biomass of the forest—including trunks, branches, leaves, and roots. Through photosynthesis, trees “inhale” $CO_2$ and “lock” the carbon into their physical structure.

2. The CO₂ Fertilization Effect

Plants use $CO_2$ as a raw material for growth. When atmospheric $CO_2$ concentrations rise:

• Photosynthesis Speeds Up: Trees can grow faster and larger than in lower-CO₂ environments.
• Water-Use Efficiency: Under high $CO_2$, plants can keep their stomata (pores) partially closed, reducing water loss while still taking in enough carbon. This allows forests in dry regions to thrive more than they currently do.

3. Ecological Saturation

Why don’t the Western Ghats show the same gains? These are “climax forests” that are already densely packed. They have reached Ecological Saturation, meaning there is little physical space or additional nutrients for significant new biomass growth compared to the open, semi-arid landscapes of Western India.

Regional Growth Projections by 2100

Region Type	Expected Carbon Gain	Primary Reason
Semi-Arid (West India)	>60% Increase	Increased rainfall and better water-use efficiency in desert-like conditions.
Central India	High/Moderate	Expanded growing seasons due to warmer, wetter weather.
Himalayas / Western Ghats	Limited Increase	Ecological saturation and vulnerability to temperature spikes/landslides.

Multiple Choice Questions (MCQs)

Q1. According to the study, under which scenario would India’s forests see the highest relative increase (up to 97%) in carbon storage?

A) Low-emission scenario

B) Medium-emission scenario

C) High-emission scenario

D) Zero-emission scenario

Q2. Which biological process is primarily responsible for the “CO₂ Fertilization Effect” mentioned in the study?

A) Respiration

B) Transpiration

C) Photosynthesis

D) Decomposition

Q3. Why are biodiversity hotspots like the Western Ghats projected to show smaller carbon gains compared to semi-arid regions?

A) Because it does not rain in the Western Ghats.

B) Due to ecological saturation (already being near their maximum capacity).

C) Because they have no CO₂ in the atmosphere.

D) Because the trees there do not perform photosynthesis.

Q4. What is the projected carbon biomass rise for India’s forests by 2100 under a “Low-Emission” scenario?

A) 10%

B) 35%

C) 62%

D) 97%

Q5. In the context of climate change, what does a forest becoming a “Carbon Source” mean?

A) It is growing more trees than ever before.

B) It is releasing more $CO_2$ (via fire or decay) than it is absorbing.

C) It has run out of carbon.

D) It is being used to make coal.

Answers:

Q1: C | Q2: C | Q3: B | Q4: B | Q5: B