when decomposition is prevented and organic carbon is buried what effect does this have on the balance of carbon dioxide removed from and returned to the atmosphere by biological activity
The correct answer and explanation is:
Correct Answer:
When decomposition is prevented and organic carbon is buried, more carbon dioxide is removed from the atmosphere than is returned, leading to a net reduction in atmospheric CO₂.
Explanation (300 words):
The carbon cycle is a natural process in which carbon atoms move between the atmosphere, biosphere, oceans, and geosphere. Biological activity, such as photosynthesis and respiration, plays a major role in this cycle. Plants absorb carbon dioxide (CO₂) from the atmosphere during photosynthesis and convert it into organic carbon in the form of plant tissue. When plants and other organisms die, their bodies typically decompose, and the carbon in their tissues is returned to the atmosphere as CO₂ through microbial respiration.
However, if decomposition is prevented, such as when dead plant material becomes buried in environments with little oxygen (e.g., wetlands, ocean sediments, or peat bogs), the organic carbon is not released back into the atmosphere. Instead, it becomes trapped underground. Over long geological timescales, this buried carbon can eventually form fossil fuels like coal, oil, or natural gas.
This process disrupts the normal balance of carbon exchange between the biosphere and the atmosphere. Normally, the carbon taken in by photosynthesis is returned through decomposition. But when burial occurs without decomposition, the amount of carbon taken out of the atmosphere exceeds the amount returned, creating a net sink of atmospheric CO₂.
This natural carbon sequestration helps regulate Earth’s climate. For instance, during periods in Earth’s history when large amounts of organic matter were buried, atmospheric CO₂ levels dropped, leading to global cooling.
In today’s context, understanding this process is critical. Human activities like deforestation and fossil fuel burning release buried carbon back into the atmosphere, reversing this natural sink and contributing to climate change. Promoting carbon sequestration—like restoring wetlands or storing biochar in soils—can help remove CO₂ from the atmosphere and mitigate global warming.