The Internal Nitrogen Cycle Betweenmicroorganisms,vegetationand Soil
نویسنده
چکیده
The major portion of the global nitrogen cycle occurs between vegetation and soil, only minor exchanges generally taking place with the atmosphere and the hydrosphere. Nitrogen conversions in soil are briefly reviewed and a global flow chart for soil nitrogen is presented. The turnover times of nitrogen in various components of this global system are compared with its turnover times in some selected ecosystems. It is shown that 95 % of the nitrogen flow in the global terrestrial system is restricted to the plant-micro organism-soil system; only 5 % of the total flow is concerned with exchanges to and from the atmosphere and the hydrosphere.
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