With reference to the forest atmosphere, consider the following statements: 1. Forests amplify noise from nearby highways. 2. The air in a forest is generally cooler than in the surrounding urban areas. 3. Forests help in maintaining the balance of oxygen and carbon dioxide. Which of the statements given above is/are correct?

The correct option is (c). Explanation Forests function as critical regulators of the local and global environment, influencing microclimates, acoustic levels, and atmospheric composition through specific biological and physical processes. Statement-wise Analysis: - Statement 1 is Incorrect: Forests act as natural sound barriers rather than amplifiers. The vegetation (leaves, branches, and trunks) and the soft forest floor absorb, deflect, and refract sound waves, effectively reducing noise pollution from nearby sources such as highways. This process is known as sound attenuation. - Statement 2 is Correct: The air within a forest is generally cooler than in surrounding urban or open areas. This is primarily due to the canopy effect, which blocks direct solar radiation from reaching the ground, and evapotranspiration, a process where plants release water vapor that cools the surrounding air. - Statement 3 is Correct: Forests play a fundamental role in the global carbon cycle and atmospheric regulation. Through photosynthesis, trees and plants absorb carbon dioxide ($CO_2$) from the atmosphere and release oxygen ($O_2$), thereby maintaining the gaseous balance essential for aerobic life. Key Takeaway: Forests provide vital ecosystem services, including noise attenuation (acting as sound buffers), microclimate regulation (lowering ambient temperatures), and atmospheric gas balance (carbon sequestration and oxygen production).

NCERT Class 7 Environment & Ecology — Chapter 1: Forests: our lifeline

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With reference to the forest atmosphere, consider the following statements:

Forests amplify noise from nearby highways.
The air in a forest is generally cooler than in the surrounding urban areas.
Forests help in maintaining the balance of oxygen and carbon dioxide.

Which of the statements given above is/are correct?

Official previous-year question

Verified 1 Aug 2026.

Options

A1 and 2 only
B2 only
C2 and 3 only
D1, 2 and 3

Did you get this right?

Solution

The correct option is (c).

Explanation

Forests function as critical regulators of the local and global environment, influencing microclimates, acoustic levels, and atmospheric composition through specific biological and physical processes.

Statement-wise Analysis:

Statement 1 is Incorrect: Forests act as natural sound barriers rather than amplifiers. The vegetation (leaves, branches, and trunks) and the soft forest floor absorb, deflect, and refract sound waves, effectively reducing noise pollution from nearby sources such as highways. This process is known as sound attenuation.
Statement 2 is Correct: The air within a forest is generally cooler than in surrounding urban or open areas. This is primarily due to the canopy effect, which blocks direct solar radiation from reaching the ground, and evapotranspiration, a process where plants release water vapor that cools the surrounding air.
Statement 3 is Correct: Forests play a fundamental role in the global carbon cycle and atmospheric regulation. Through photosynthesis, trees and plants absorb carbon dioxide ($CO_2$) from the atmosphere and release oxygen ($O_2$), thereby maintaining the gaseous balance essential for aerobic life.

Key Takeaway: Forests provide vital ecosystem services, including noise attenuation (acting as sound buffers), microclimate regulation (lowering ambient temperatures), and atmospheric gas balance (carbon sequestration and oxygen production).

Your note

More from Chapter 1: Forests: our lifeline

With reference to the structure of a forest, consider the following statements: 1. The branchy part of a tree above the stem is known as the crown. 2. The roof-like structure formed by the branches is called the root system. 3. The forest floor is the only layer found in a forest. Which of the statements given above is/are correct?

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Consider the following statements regarding the vegetation layers in a forest: 1. Giant and tall trees constitute the top layer. 2. Shrubs and tall grasses form the lowest layer of the forest. 3. Herbs form the lowest layer of vegetation in the forest. Which of the statements given above is/are correct?

easy

In a dense forest ecosystem, the forest floor receives minimal sunlight primarily due to:

easy

With reference to the role of forests in the water cycle, consider the following statements: 1. Trees release water vapour into the air through the process of condensation. 2. The forest canopy intercepts raindrops, preventing them from hitting the ground directly. 3. Forests facilitate the infiltration of water into the ground. Which of the statements given above is/are correct?

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Consider the following statements about the "forest floor": 1. The forest floor is generally dark due to the dense canopy above. 2. The forest floor is completely devoid of any dead or decaying matter. 3. The forest floor is sterile and supports no living organisms. Which of the statements given above is/are correct?

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The correct option is (c).

Explanation

Statement-wise Analysis:

Statement 1 is Incorrect: Forests act as natural sound barriers rather than amplifiers. The vegetation (leaves, branches, and trunks) and the soft forest floor absorb, deflect, and refract sound waves, effectively reducing noise pollution from nearby sources such as highways. This process is known as sound attenuation.
Statement 2 is Correct: The air within a forest is generally cooler than in surrounding urban or open areas. This is primarily due to the canopy effect, which blocks direct solar radiation from reaching the ground, and evapotranspiration, a process where plants release water vapor that cools the surrounding air.
Statement 3 is Correct: Forests play a fundamental role in the global carbon cycle and atmospheric regulation. Through photosynthesis, trees and plants absorb carbon dioxide ($CO_2$) from the atmosphere and release oxygen ($O_2$), thereby maintaining the gaseous balance essential for aerobic life.