The correct option is (a).
Explanation
The interrelationship between vegetation, atmospheric composition, and the hydrological cycle. It specifically tests the role of forests in regulating carbon dioxide levels and the impact of global warming on water cycle stability.
Statement-wise Analysis
- Statement 1 is Correct: Photosynthesis is the process by which green plants synthesize nutrients from carbon dioxide and water using sunlight. Plants absorb carbon dioxide from the atmosphere to produce glucose and release oxygen. Therefore, carbon dioxide is an essential requirement for this process.
- Statement 2 is Incorrect: Trees act as natural carbon sinks by absorbing carbon dioxide during photosynthesis. Deforestation (fewer trees) reduces the capacity of the biosphere to remove carbon dioxide from the atmosphere. Consequently, fewer trees result in an increase, not a decrease, in the amount of atmospheric carbon dioxide, contributing to the greenhouse effect.
- Statement 3 is Incorrect: An increase in global temperature disturbs the water cycle rather than stabilizing it. Higher temperatures increase the rate of evaporation and the atmosphere's moisture-holding capacity. This leads to an intensification of the water cycle, resulting in erratic rainfall patterns, more severe droughts, and extreme precipitation events.
Key Takeaway
Deforestation leads to an accumulation of atmospheric carbon dioxide (a greenhouse gas), which drives global warming. Global warming, in turn, disrupts the water cycle, making weather patterns more extreme and unpredictable.