Ecological interaction as a source of economic irreversibility

Irreversibility can be either physical or economic in origin. For example, the extinction of a species is physically irreversible. On the other hand, contamination of lake-bottom sediments by mercury is not physically irrever sible (the mercury and/or sediments can be physically removed), but the cos t is so high that it can be said to be economically irreversible. This pape r argues that economic irreversibility associated with environmental change is much more common than typically discussed in the economics literature. The source of the problem is the inherent complexity of ecological relation ships. The paper discusses the origin and policy importance of these indire ct irreversibilities.