Biogeochemical cycles are named for the cycling of biological, geological and chemical elements through Earth and its atmosphere. The cycles move substances through the biosphere, lithosphere, atmosphere and hydrosphere. Cycles are gaseous and sedimentary. Gaseous cycles include nitrogen, oxygen, carbon and water. These elements cycle through evaporation, absorption by plants and dispersion by wind. Sedimentary cycles include the leeching of minerals and salts from the Earth's crust, which then settle as sediment or rock before the cycle repeats.Repetition of the cycles is important. Plants absorb carbon dioxide and release oxygen, making the air breathable. Plants also acquire nutrients from sediment. Animals acquire nutrients from plants and other animals, and the death of plants and animals returns these nutrients to the sediment as they decay. The cycle then repeats and allows other living things to benefit.The simplest example of biogeochemical cycles at work includes water. Water evaporates from the oceans, condenses as clouds and precipitates as rain, which returns the water back to the earth in a cycle.