The geochemical cycle refers to the natural processes that recycle essential elements and compounds through the Earth's systems, including the atmosphere, hydrosphere, lithosphere, and biosphere. These cycles involve the movement of elements like carbon, nitrogen, and phosphorus, which are crucial for life. They help maintain the balance of nutrients in ecosystems and support various biological processes. Each geochemical cycle consists of different stages, such as weathering, sedimentation, and decomposition. For example, in the carbon cycle, carbon dioxide is absorbed by plants during photosynthesis, then released back into the atmosphere through respiration and decay. Understanding these cycles is vital for managing natural resources and addressing environmental issues.