man-induced turnover The additional flow of an element through the active part of a biogeochemical cycle that results from human activity. For example, by burning fossil fuels humans add an extra 6.7 billion tonnes per year of carbon to the turnover of the carbon cycle, which is naturally about 75 billion tonnes per year. (One billion is equal to one thousand million, 10⁹.)

man-induced turnover The additional flow of an element through the active part of a biogeochemical cycle, which results from human activity. For example, by burning fossil fuels humans add an extra 5 billion tonnes per year of carbon to the turnover of the carbon cycle, which is naturally about 75 billion tonnes per year. (One billion is equal to one thousand million, 109.)