The Analysis and Calculation of Energy Flow and Ecological Efficiency in Agro-Ecological Engineering——With the Beijing Liuminying as an Example

The paper gives a general description of the energy flow in Liuminying agro-eco-system through the facts of on-the-spot tests, quantitative analysis and calculation of output-input ratio of energy as well as of some main subsystems’ ecological efficiency. The results show that the output-input rate of the artificial supplementary energy was 1, the energy conversion efficiency of primary producer reached 1.54% and the light energy utilization rate was 0.65%. All kept higher rates. However, the ratio of secondary production was a little lower. The paper also gives a brief analysis of the calculation result and the relevant conclusion as well.