In the past, human groups and tribes have often exhausted resources available to them locally and this led to localised collapse and enforced migration. Until now, resource depletion has generally occurred only on such a localised scale. However, since the industrial revolution, per capita consumption has risen and trading has become truly global; the exponential increase in population numbers is causing an impact which is being felt around the whole planet. There are no more "empty continents" left to which we can migrate.
In common with all other living creatures, humans require certain essential resources in order to survive and prosper. The most basic requirements include fresh water and food. Fresh water is a product of the natural climate and the water cycle. Food depends on other living things; plants, animals and microorganisms which in turn have their own resource requirements.
This web of interconnected living things and other natural resources powered by the sun's energy makes up the ecosystem on which we all depend. To sustain more than a very basic quality of life, we rely on many other resources to provide the raw materials which go into making the clothes, buildings, vehicles and other goods we enjoy and depend on in our daily lives. These raw materials may be geological, such as minerals, or may come from plants, animals or other microorganisms.
Throughout history, the consequences of resource depletion are well documented. When resources run low populations are put under extreme pressure. Some migrate; others are driven to conflict with their neighbours.
If we want a good quality of life, it is essential that we all find a way to live within the limits of the resources available to us.
It is also important to understand the effect that human consumption of resources has on other living species: the healthy ecosystems we rely on to survive in turn depend on countless other species.
Read more about our dependence.
Read more about biocapacity and ecological footprinting.