Biogeochemical cycles and climate
Energy flows directionally through ecosystems, entering as sunlight and leaving as heat during energy transformation between trophic levels but the flow of nutrient is cyclic. The nutrients are vital for the growth of organisms and sustenance of life in the biosphere is derived by the interaction of matter and energy. The organic and inorganic matters move reversibly in the atmosphere, hydrosphere, biosphere and Lithosphere through various cycles known as a Biogeochemical cycle. This recycling of the nutrients is called biogeochemical or nutrient cycling. (Bio - living; geo - rock; chemical - element) .