Ecological Economics

As noted above, sustainable economic systems can only be based on the wise use of renewable resources. However, the most common way in which humans have used potentially renewable resources is by "overharvesting," that is, exploitation that exceeds the capacity for renewal so that the stock is degraded and sometimes made extinct. In other words, most use of potentially renewable resources has been by mining, or use as if it were a nonrenewable resource.

There are many cases of the mining and degradation of potentially renewable resources, from all parts of the world and from all human cultures. In a broad sense, this syndrome is represented by extensive deforestation, collapses of wild fisheries, declines of agricultural soil capability, and other resource degradations. The extinctions of the dodo, great auk, Steller's sea cow, and passenger pigeon all represent overhunting so extreme that it took potentially renewable resources beyond the brink of biological extinction. The overhunting of the American bison and various species of seals and whales all represent biological mining that took potentially renewable resources beyond the brink of economic extinction, so that it was no longer profitable to exploit the resource.

These and many other cases of the degradation of renewable resources occurred because conventional economics did not value resource degradation properly. Consequently, profit was only determined on the basis of costs directly associated with catching and processing the resource, and not on the costs of renewal and depletion. Similarly, conventional economics considers non-valuated goods and services such as biodiversity, soil conservation, erosion control, water and nutrient cycling, and cleansing air and water of pollutants to be free resources so that no costs are associated with their degradation.