Renewable resources can be harvested or collected over and over again. They are living resources, like farm crops and frees, that grow back or renew themselves, cycle after cycle. Non-renewable resources can be harvested or collected only once. They don’t renew themselves or grow back. Once used, they are gone forever.
They also include such natural resources as the solar energy, air, and water because of their almost inexhaustible supply. Solar energy, water and air form a triumvirate that has helped the germination of human life as also all other life forms and has been responsible for its further progress in an immeasurable manner.
Water is generally considered a perennial natural resource as it meets some of the vital requirements of life on earth. The humans are no exceptions in the matter and use water for sustaining life as also for a variety of other purposes.
There are some resources that are replenished through extremely slow natural cycles. Such resources can therefore be considered as non-renewable for all practical purposes. Since the rate of formation of these resources is very slow, each time they are used some depletion in their reserve does occur.
The rate, at which they are used, therefore, determines whether they are likely to last long or diminish sooner. The main nonrenewable resources which human societies have been using since the most remote past are metals and mineral resources and soil.
The metals and minerals are sometimes available on or near the surface or otherwise have to be mined. The soil is formed over hundreds of years as a result of a complex interaction between organisms and the physical surface of the earth.
Climate also plays a significant role in soil formation. The metals and minerals are seldom available in pure form in nature and are mostly extracted from below the ground or from the hills in the form of ores. This implies the availability of knowledge and a certain level of the development of technology of extraction.