Topological Network Theory and Its Application to LCA and IOA and Related Industrial Ecology Tools: Principles and Promise

Abstract

One way to study complex systems is by methods from topological networktheory, that concentrate on the topological structure of the system interms of vertices (nodes) and edges that connect pairs of vertices. The lasttwo decades, topological network theory has seen a wide range of applications.In this paper, we explore its potential for two of the model systemsthat are central to industrial ecology (IE): life cycle assessment(LCA) and input-output analysis (IOA), with the aim of finding outwhether this theory offers insights that are useful to IE. We describe theprinciples of topological network theory, as well as the possible rules fortranslating LCA and IOA systems into a formal network. We apply thistheory to two cases, the ecoinvent LCA database, and the monetary IOtablefor the European Union in 2007. Our conclusions are mixed. It isnot entirely clear what the resulting network indicators imply for a specificLCA case or IOA case. Although the results obtained are perfectlyexplainable and thus do make sense, they appear to be very sensitive toarbitrary choices, such as the level of aggregation. Moreover, it appearsto be difficult to include the environmental aspect in the network analysis,so that we end up with analyzing an industrial network rather thanindustrial-ecological network