%0 Journal Article
%T Macroscopic Features of Nitrogen Transformation and Cycling in the Agroecosystem in China and It''s Implications to Ecological Agriculture<br>我国农牧系统素转化循环的宏观特征与生态农业
%A Han chunru
%A Xie zongfang
%A <br>韩纯儒
%A 解宗方
%J 中国生态农业学报
%D 1993
%I 
%X Quantitate diagram models are developed which illustrate the macroscopic features with its temporal changes of N transformation and circulation in Chinese agroecosystem,by using a simplified model of N cycling with 3 untrient pools of crop, livestock and soil.The results indicated an increasingly intensified tendency that Chinese agriculture is becoming more inorganic and less efficient.While the total crop biomass N product,the food N supply and the proportion of animal N in total food N were increased 2.3, 2 and 4 times more respectively in Chinese crop-livestock system by the end of nineteen eighties than at the beginning of ninetenn fifties,the total production N input and N fertilizerconsumption were increased in 8 and 187 times,with simultaneous lowering in the proportion of organic to total production N input from 97% to 25%,and decreasing the production efficiency of total and inorganic N input in terms of producing main product N from 1.12 and 3.63 to 0.34 and 0.46 respectively.The supply of forage N would have to be doubled to tripled and fertilizer N consumption more than doubled in order to meet the food N demand of an improved quality for the population grown to 1.3-1.5 billions,this would brings out serious environmental consequences.Possible options of ecological agriculture strategy are also discussed in its potentials of dealing with challenges in respect to the N transformation and circulation in Chinese agroecosystem.
%K Agroecosystem
%K Nitrogen cycling
%K Nitrogen transformation
%K Ecological agriculture
%K Production efficiency<br>农业生态系统
%K 氮循环
%K 氮素转化
%K 生态农业
%K 生产效率
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=03F54A49DE00578AA0E5DDF5BC021AA7&cid=1A8B5357F0EF07B8&jid=AB3ABF502E2E1FF39F0E3B80164C9031&aid=068AEAB5801B85109A106A80FE044E4F&yid=D418FDC97F7C2EBA&vid=CA4FD0336C81A37A&iid=CA4FD0336C81A37A&sid=9FFCC7AF50CAEBF7&eid=68D88C2FCF9C3098&journal_id=1671-3990&journal_name=中国生态农业学报&referenced_num=0&reference_num=0