Emergy analysis for agricultural system of Yulin area in China

In this paper, emergy analysis is used to analyze the agro-ecosystem of Yulin area, the Loess Plateau in China, in order to provide the theoretical basis for the rational utilization of natural resources and sustainable development of the agro-ecosystem. Emergy analysis is appropriate for this task because of its ability to transform different types of inputs to a common form to allow meaningful evaluations across the input-output emergy, and emergy indexes of the agro-ecosystem. Because the agro-ecosystem deeply depends on inner environmental resources, it is backward but more sustainability than developed area. To further develop the agro-ecosystem in Yulin area, the exchange of material and energy with the outside world should be appropriate enhanced, so that the technological level of the agro-ecosystem and the production efficiency can be improved. The paper could provide guidance for the sustainable development of the agro-ecosystem through the assessment of emergy indexes.