Analysis of the functional orientation of agricultural systems from the perspective of resource circulation

摘要

Accurately identifying the functional orientation of the different components of a circular agricultural (CA) system is crucial for improving the ecological efficiency of the system. However, the functional orientation still needs more in-depth quantitative analysis. This study serves as a feasible way of solving this problem. An energy flow model has been developed based on the Odum Energy System Language, which is a method based on mathematics, energy flows, cybernetics and hierarchical relationship and can effectively modelling the agriculture resources recycling and environmental impact. The case study of the CA system of Fuqing Xingyuan Company has been conducted, quantitatively analyzing the functional orientation differences between different components in the CA system. The results showed that: (1) The dragon fruit planting system benefited from recyclable resources, but did not contribute recyclable resources, and was positioned as a "beneficiary system". If the planting amount of the dragon fruit increasing by 10% (Scenario 1), the resources allocation would be unbalanced, and the total economic output of the CA system would reduce by 0.17% annually; otherwise, it would increase by 0.29% ( Scenario 2); (2) The pig breeding system drove the overall operation of the system and provided recyclable resources for other components, and was position as "drive system". If the breeding amount increases by 10% (Scenario 3), the pig breeding system would increase the recyclable resource input of the CA system, and the total economic output of the CA system would rise and fluctuate, increasing by 0.20% annually. Otherwise, the average annual reduction would be 0.59% (Scenario 4). The changing trend of the economic output under different scenarios supported the results of functional orientation analysis. It provides an effective way to identify the functional orientation of different components in a CA system based on the Energy System Language. (C) 2020 Elsevier Ltd. All rights reserved.