Carbon Cycle

The carbon cycle is divided into two major interconnected systems:

• Fast cycle (days to years): Involves the continuous exchange of carbon between the atmosphere, biosphere, and oceans. Plants capture CO₂ through photosynthesis, which is then released again by respiration, decomposition, and combustion of organic matter.
• Slow cycle (thousands to millions of years): Includes the accumulation of carbon in the form of carbonate rocks, sediments, or fossil fuels. This carbon can be released through volcanic activity or fossil fuel combustion.

Key stages of the cycle:

• Photosynthesis: Capture of atmospheric CO₂ by plants and photosynthetic organisms.
• Respiration and decomposition: Release of CO₂ by living organisms and decomposing matter.
• Sedimentation: Accumulation of carbon in soil and seabeds.
• Combustion: CO₂ emissions from burning biomass and fossil fuels.
• Ocean-atmosphere exchange: Oceans absorb and release CO₂, acting as natural sinks.

Human activities, such as deforestation and intensive use of fossil fuels, are altering this natural cycle, increasing CO₂ concentrations and accelerating climate change.