During the 20th century the flow of processed physical goods to support the industrial economy of the USA increased exponentially. This trend continued after a slight pause around 1970-80. From 1975 onward, the data show that while hidden flows decreased, processed flows for fuels, physical goods and agricultural products increased at the same rate as population. With the exception of physical goods obtained from agricultural resources, the per capita use of material for this purpose continues to increase. The end of the century saw a resurgence in the use of construction materials, primary metals and wood, a consequence of a robust economy and, probably, urban sprawl. During that same period, the increased use of synthetic polymeric material affected both metals and natural fibers, and even though Americans are using increased amounts of paper, packaging applications have likely also been affected. Of major significance is the fact that they are becoming increasingly dependent on fossil fuels for material, as well as energy uses, so that disruptions in supply, or price increases, will affect multiple sectors of the US industrial system. During the 20th century, GDP generally grew considerably faster than population. Materials use kept pace with economic growth until about 1970, at which time GDP grew at a faster rate However, from an industrial ecology perspective, decoupling of material use with respect to economic growth has little meaning as long as the population continues to rise, and material use continues to grow.
Was this article helpful?