Nutrient from environment and its effect in nutrient resources management of ecosystems: a case study on atmospheric nitrogen deposition.

In this paper,a case study on atmospheric nitrogen(N) deposition in the main regions of China is carried,and the definition,forms and amount of nutrient from environment(NFE) and the relationship between NFE and N discharge to atmosphere caused by human activities are summarized.Based the study results in this paper and the references,it is fund that N wet and dry deposition has become as an important nutrient resources in agricultural and natural ecosystems in China.The total annual amount of N deposition and other N forms from environment in China is up to 1.8×107 t,and equals to approximately 60% of the national N fertilizer consumption.Therefore,it is crucial to fully utilize the environmental nutrient resources by managing the nutrient resources in an integrative so as to achieve the sustainable development of both agricultural and natural ecosystems.It is suggested to develop a nationwide network for monitoring and quantitatively researching the N wet and dry deposition and carrying out the long-term experiment about the ecological response and feedback of some sensitive ecosystems to N deposition from atmosphere.