In a world deeply concerned about future accessibility of physical resources, especially materials, water and energy, the young field of industrial ecology brings resolute attention to tracking the flows of these resources through systems at different scales. Material flow analysis is an industrial ecology tool used to examine system metabolism by tracking the input, output, conversion and accumulation of materials, water, energy or selected substances, helping to inform decisions about resource availability, waste management and pollution reduction at local, regional or global levels.

With the exception of several nature reserves, the island city-state of Singapore is highly urbanized, and has been dependent upon industrial and manufacturing activities for its national standing and economic growth. As such, mapping Singapore’s ‘urban metabolism’ through a material flow analysis (MFA) approach, with a particular focus on materials catalogued by international trade databases, is useful for understanding the island’s level of sustainable resources use within the context of the global economy and ecosystem.

This study compares relevant data describing Singapore’s material flows for the years 2000, 2004 and 2008. Domestic material consumption on the island is found to be highly variable across the three study years. This primarily reflects Singapore’s levels of construction activity, including considerable additions of actual land area to the island. The flux in the quantity of sand imports to Singapore illustrates the volatility that one category of goods can introduce to the material record of an otherwise stable economy. For countries that are becoming increasingly dependent on imported products, the implication is that a growing share of the impact is taking place in other countries. Global economic trends are also determined to have an effect on Singapore’s additions to stock vs. its exports, as its gross domestic product is highly reliant on trade activity.