The overexploitation of natural resources is a tale as old as time, and humans have always exploited the most accessible and richest resources first. The deepest and most fertile soils, the tallest, straightest trees and the most mineral laden ore bodies were the first to be harvested.
In a world of virgin resources, resource depletion was not yet a concern. Early agriculture in the golden triangle took place upon meters of rich alluvial soils. Timbers were drawn from towering stands of old growth forests. Metals were melted from outcroppings of ore by lighting fires beneath them. Fish were harvested by the basket.
Over time, we’ve had to search further for the resources we need and work harder once we found them. That leaves us with a trend of using poorer and poorer sources for the material necessities of life, leading to resource depletion. Although most of the richest resources on the planet were being used and reduced by the middle of the 20th century it was an easy problem to ignore.
The reason for this burgeoning resource scarcity was one simple word: oil- code for cheap, dense, flexible energy.
Oil has allowed us to exploit every other resource to a far greater point of depletion than would have been possible with any other form of energy. It is the uber-commodity, without which our way of life cannot exist.
Now that oil scarcity is making it more expensive to produce, the richness of the other resource bases upon which we depend is becoming much more obvious. Oil depletion causes us to rely on other resources, making resource scarcity an increasingly broad problem.
The lower the grade of ore (say ounces of mineral per tonne of rock), the more rock must be processed to obtain the mineral.
If energy costs are low and falling, resource depletion is not a critical problem. However, oil has ceased to be almost free. 40 years ago, the biggest and richest reserves of oil in the Arabian peninsula and West Texas required one barrel of oil to discover and extract 100 barrels of oil.
Oil scarcity causes higher energy costs, meaning that every other resource automatically faces scarcity and higher costs as well. To avoid resource scarcity, sustainability, on the other hand, means much greater conservation of renewable resources and much lower levels of consumption of minerals.