Emergy Evaluation On Agricultural Operation Patterns In The Agro-Pastoral Transition Zone Of Northern China

In this article,emergy analysis was used to set up the emergy indices of pattern evaluation to roundly evaluate traditional cropping pattern( I ),crop-animal breeding combined pattern(II) and forage-animal breeding coupled pattern(III) operating in Daliangwa Country of Gansu Province,which belongs to typical the agro-pastoral transition zone of Northern China,as a case study of pattern evaluation for showing the compare'advantage of agricultural patterns and the direction of adjusting agricultural structure.The result showed:1. In the pattern III,Emergy input was the main of Renewable resource, soil loss and operation cost was lower,organic manure instead of fertilizers, the industrial energy reduced to 7.9%.Because of cropping and animal breeding was coupled in patternIII,self-system' feedback energy of pattern III was most inputted than pattern I and pattern II, but the proportion of pattern III was 75 times of pattern I and 1.8 times of pattern II .So organization capability and system vitality was stronggest in the pattern III.2. The energy dissipation was lower in the pattern III,NEYR of pattern III was 1.8 times of pattern I and 1.2 times of pattern II respectively,emergy benefits of pattern III was highest, SFR of pattern III was 1.2 times of pattern II and 3.5 times of pattern II,but EIR and ELR of pattern III was lowest.ESI of pattern III was 160 times of pattern I and 5.6 times of pattern II ,so pattern III had more sustainable development.3. Market economic and EM$ benefits of pattern III was better than pattern II and I .4. To extend pattern III for agro-grassland agriculture,agro-grassland agriculture was operated,which was the direction of adjusting agricultural structure and the outlet of coming true sustainablity in the agro-pastoral transition zone of Northern China.