Material Flow of Iron in Global Supply Chain

Abstract

Recently, sustainable management of resources has become an increasingly recognized issue. Accordingly, interest in understanding the relationship between natural resources consumption and the global product supply chain has also been increasing. Material flow analysis (MFA) is a useful tool for understanding resource consumption and material cycles in national economies. However, detailed MFA studies of the materials embedded in foreign trade flows are rare.This study identified global trade flow of iron embedded in bilateral trade between 231 countries by multiplying the trade volume of the commodities in the BACI (Base pour l'Analyse du Commerce International) database and the iron content of each commodity. We focused on the cases of Japan, China, and United States, and estimated the mass of iron embedded in imports and export. The identified total flows of iron embedded in international trade were 1.15 × 10 9 t-Fe with 35.2% of the flows concentrated in three countries, Japan, China and United States, which are major crude steel production countries.KEY WORDS: material flow analysis; international trade; input-output analysis; supply chain; iron and steel.

Physical and Monetary Methods for Estimating the Hidden Trade of Materials

“…The latter is thus newer and less widely used up to now. However, its advantages of (1) relying on monetary trade data that are more widely available than the physical trade data and (2) applying metal concentration data that can be easily generated by the WIO-MFA model make the monetary method very promising and useful in building global trade networks of metals and other materials [30][31][32]. In addition, this study's finding (that the metals trade embedded in final products estimated by the two methods are not too much different at the end-use product group level) suggests that the monetary method can be pretty reliable if the global trade networks are built for all final products or for products in an end-use product group.…”

“…Originally, all trade data come from the customs statistics of countries or territories. The aluminum, copper, and iron trade analyzed in this study refers to the trade of three metals measured in physical Besides the abovementioned publications, there have been quite a few other cases of material trade flow analysis applying either the physical method [24][25][26][27][28][29] or the monetary method [30][31][32], and some of these studies even analyze the global supply chain or network of materials among countries and territories. The salient findings of these studies are reasonable, such as that at the final goods level, Japan is a net exporter of iron and aluminum embedded in final products because it has been a provider of automobiles and many other manufactured products to the world [21].…”

“…Compared to the physical method, the monetary method has at least two advantages: (1) it enables researchers to infer material concentrations for all concerned final products just by using the IO-based WIO-MFA model, therefore avoiding spending a lot of time collecting data on metal concentrations; (2) unlike trade data in physical units that sometimes are not recorded in the customs statistics, trade data in monetary units always exist; especially for the United States and Japan, these monetary trade data are already well compiled in their IO table with ≈400 sectors [22,23], thus can be directly used and will help save a great deal of time. Besides the abovementioned publications, there have been quite a few other cases of material trade flow analysis applying either the physical method [24][25][26][27][28][29] or the monetary method [30][31][32], and some of these studies even analyze the global supply chain or network of materials among countries and territories. The salient findings of these studies are reasonable, such as that at the final goods level, Japan is a net exporter of iron and aluminum embedded in final products because it has been a provider of automobiles and many other manufactured products to the world [21].…”

Analysis of China’s Iron Trade Flow: Quantity, Value and Regional Pattern

“…So far, many scholars have made extensive use of material flow analysis methods to study the material flow of metal resources [5]. Qiangfeng and other scholars have studied the iron trade flows between China and the rest of the world [6]; Nakajima and others analyzed and calculated the global iron trade flow [7]. These previous studies have promoted the progress of MFA and provide new ideas for follow-up research.…”