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How do deforestation and fossil-fuel burning affect the carbon dioxide cycle?

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Zenaida macroura: mouring doves — ecology Mourning doves (*Zenaida macroura*) on their nest protected within the prickly branches of a cactus in the Sonoran Desert, Arizona, U.S.

Deforestation and the burning of fossil fuels disrupt the natural equilibrium of the carbon cycle by increasing the concentration of carbon dioxide (CO₂) in the atmosphere.12

Impact of Fossil-Fuel Burning

The combustion of fossil fuels—such as coal, oil, and natural gas—releases carbon that was stored over geologic time back into the atmosphere. This anthropogenic emission adds a significant load of CO₂ that exceeds the capacity of natural sinks, such as oceans and terrestrial vegetation, to absorb it. This accumulation enhances the greenhouse effect, contributing to global warming.1342

Impact of Deforestation

Forests act as vital carbon reservoirs, sequestering CO₂ through photosynthesis. Deforestation affects the cycle in two primary ways:15
* Loss of Sequestration: By removing trees, the planet loses the capacity to take up CO₂ from the atmosphere.5
* Release of Stored Carbon: When forests are cleared and burned, the carbon stored in their biomass is released directly into the atmosphere as CO₂.5

Together, these human activities have caused atmospheric CO₂ levels to rise to their highest points in millions of years, fundamentally altering global climate patterns.23