Quantitative indicators for evolution of a typical iron and steel industrial symbiosis network

Abstract

How to optimize the industrial symbiosis network and quantify its evolution are still an opened problem in industrial ecology. A typical iron and steel industrial symbiosis network (ISISN) was chosen to find the changes of indicators screened of carbon flow and iron flow with symbiotic measures added or adjusted. And indicators applied in this study are to comprehensively quantify and characterize the evolution of the structure, function, and performance of two metabolisms in different scenarios. Results show that Average Path Length (APL), Finn Cycling Index (FCI), Detritivory to Herbivory ratio (D:H) mainly be used to quantify the function characteristics related to structure of the medium flow metabolism, and Mean Trophic Level (MTL), Keystoneness (KS), Structural Information (SI) mainly quantify the structure characteristics related to function. Flow-based Information indices are mainly applied to quantify the structure, function and organization characteristics of symbiosis network. Carbon metabolism is in a subordinate position with more development potential and redundancy in the symbiosis network which is in a stable structure of intra-firm symbiosis while iron metabolism is the key with strong dominance and more efficient. All the indicators are sensitive to symbiotic components and symbiotic measures increased that reveal the performance improved and able to comprehensively detect the evolution of carbon and iron metabolisms of the symbiosis networks. Furthermore, these indicators may be used for decision makers to measure and assess industrial symbiosis network though there is still no testing applicability of indicators accurately due to industry type and a single case.