Understanding the Carbon Cycle: Processes and Reservoirs | Khan Academy

What is the Carbon Cycle?

• 💡 The carbon cycle describes how carbon moves through different parts of the environment, known as carbon reservoirs.
• 🌍 Carbon reservoirs can be organic (living organisms, their remains) or inorganic (rocks, water, atmosphere).

Key Processes in the Carbon Cycle

• 🌿 Photosynthesis: Plants use sunlight to convert atmospheric carbon dioxide into glucose, acting as a carbon sink by removing carbon from the atmosphere.
• 💨 Respiration: Plants and animals break down glucose for energy, releasing carbon dioxide back into the atmosphere, making it a carbon source.
• 🦠 Decomposition: Decomposers like bacteria and fungi break down dead organisms, releasing carbon dioxide into the atmosphere, also acting as a carbon source.

Biological vs. Geological Carbon Cycles

• 🌱 The biological carbon cycle involves photosynthesis, respiration, and decomposition, moving carbon between the atmosphere and organisms relatively quickly (years).
• ⏳ The geological carbon cycle involves carbon stored in rocks and fossil fuels over millions of years.
• 🌋 Carbon is released from geological reservoirs through volcanic eruptions and human combustion of fossil fuels.

Human Impact and Solutions

• 🔥 Burning fossil fuels releases carbon stored for millions of years into the atmosphere, increasing global temperatures.
• 🌳 Efforts to move carbon back into long-term reservoirs include planting trees, protecting ecosystems, and improving land use.
• 🌍 Actions like planting trees, protecting natural ecosystems, and improving land use can help store more carbon and mitigate climate change.