Patterns of embodied pollutant emissions along the global light industrial chain: A complex network perspective

Abstract

With the upgrading of consumer goods and accelerating trade globalization, enormous amounts of pollution related to the light industry sector's production are transferred across borders along the global industrial chain, but their network patterns and evolution remain unclear. Here, we developed an analytical framework for trade-embodied pollutant emissions transfer (TPET) network by combining complex network theory and input– output theory to analyze the network of 16 light industries in 43 economies from 2000 to 2014. We revealed the critical economies, key industries, critical paths and their evolution trends. The light industry sector's total TPET was consistently large, but many factors (e.g., upgrading consumer goods, increasing trade volume, the 2008 financial crisis) caused large fluctuations. The network densities remained relatively high, with an obvious small-world property and significant centralization. Large economies (especially the world's top 10 economies with a total GDP exceeding US $1.86 trillion in 2014) were critical nodes due to their stable and dominant importance, but played opposite roles (i.e., net TPET importers vs. net exporters). Due to large differences in domestic demand, and environmental regulations, high-income economies (e.g., the U.S., and Germany) were the leading net TPET exporters, whereas low- or middle-income economies (e.g., China, Russia) were the dominate net importers; TPET therefore primarily flowed from high-income to low- or middle-income economies, with substantial growth over time. The electricity, gas, steam and air conditioning supply industry, the manufacture of other non-metallic mineral products, the manufacture of basic metals, and the fishing and aquaculture industry together accounted for 81.2 and 89.0% of total trade-embodied NOX and SOX emissions, respectively; they were thus key industries. To reduce emissions, critical economies should consume more environment-friendly products, strengthen technological innovation and pollution control in key industries, and expand environmental cooperation with other countries. Our results provide insights into the global light industry sector's TPET characteristics and reduction strategies. They also provide a reference for adjusting trade patterns and industrial structures.