After reading this article you will learn about the classification of resources.
The resources that are essentially inexhaustible in considered as renewable resources. Solar, wind, tides and flowing water falls under this categories. It is expected that the solar energy will last at least 6.5 billion years while the sun completes its lifecycle.
On the contrary a potentially renewable resource can be renewed fairly rapidly (few hours to several decades) through natural processes. Examples of such resources include forest, grassland, animal, fresh water, fresh air and fertile soil. But the resource renovation rate must be faster than resource exploitation.
The highest rate at which a potentially renewable resource can be used indefinitely without reducing its available supply is called its sustainable yield. Several types of environmental degradation can change potentially renewable resources into non-renewable or unusable resources.
One of the cause of environmental degradation is overuse of common-property resources, which are owned by none and available to all users free of charge. Most of the potentially renewable resources (viz. clear air, open ocean, fresh water, stratospheric ozone etc.,) fall under common property categories. One of greatest problem of today’s world is the loss of such common properties through over-exploitation. This is often referred to as “tragedy of the common”.
The following are the major environmental degradation that induces potentially renewable resources into non-renewable one:
1. Urbanisation of productive land;
2. Salinisation and water logging of soil;
3. Poor soil management;
4. Wetland destruction;
6. Ground water depletion;
7. Pollution of air, water and land;
8. Livestock overgrazing;
9. Reduction in biodiversity by eliminating habitats and species.
Resources that exist in a fixed quantity in the earth’s crust and thus theoretically can be completely used up are called non-renewable or exhaustible resources. On a time scale of millions to billions of years, such resources can be renewed by geological processes. But on the much shorter human time scale of hundreds to thousands of years, these resources can be depleted much faster than they are formed.
These exhaustible resources include energy resources (Coal, Oil, Natural gas, Uranium), metallic mineral resources (iron, copper, aluminium) and non-metallic mineral resources (salt, clay, sand and phosphate). Some of these resources may be recycled and – viz., metallic resources while others cannot be recycled viz., energy resources. (Coal, Oil and Natural gases).