Every habitat, no matter how big or small has identifiable things which make it the way it is. The characteristics of an environment are vital in determining which organisms can and cannot live there. These characteristics have been dubbed “factors” and essentially they are just things in the environment which determine what can and cannot live there. These environmental characteristics can be split into two very distinct categories; abiotic and biotic factors. Biotic factors are ones caused by living organisms. Prominent examples of biotic factors include predation and disease. It would therefore be only a minor leap of logic to assume (correctly) that “abiotic” factors are ones determined by things which are not living.
1. Climate
The type of climate and the weather of a habitat is a very prominent abiotic factor. It can be split down into smaller sub-sections such as rainfall, temperature and wind speed, however too keep things simple we shall talk about weather and climate as a whole.
The weather experienced within an area is extremely important in determining what can and cannot live there; examples of this phenomenon are all around us. A cactus can easily cope with the low rainfall and the high temperatures experienced within the desert, however other garden plants will have a much harder time coping. Indeed the same applies for mammals and reptiles, an animal adapted for the factors present within a rainforest will not survive in climates which are too difficult to adapt to.
2. Topography
Topography is the study of the way the ground lies including altitude, gradient and drainage. The way the earth lays is vital in determining which species can inhabit a habitat. As altitude changes so does temperature (dropping by one degree per kilometre) and the make-up of the air making it harder for species to adapt. If a slope has a steep gradient then larger plant life (i.e. trees) will have a considerably harder time inhabiting that region, leaving shrubs and herbaceous plants to become more dominant within the area. The variability of plant life due to topography also has a large effect on animals, which are largely dependent on the producers for food and shelter.
3. Pedology
Pedology is the study of the soil in area. The type of soil, its pH, mineral concentrations and water retention will all play a big role in the type of organisms which can live within a habitat. A soil with a high pH or a high salt content will be unsuitable for many types of plants to grow in, limiting the biodiversity which will occur in an area. Water retention is also a very important for organisms to live. If water drains away too fast plants will not get a chance to absorb enough via osmosis, if it does not drain away fast enough it will cause plant cells to become turgid and effectively drown the plant.
4. Water
Water is the molecule which supports every single life form on Earth and thus you would expect it to be one of the key players in abiotic factors, and indeed it is. If the weather isn’t generous and doesn’t rain regularly then plants and animals will find it hard to survive without their staple drink. Plant life is almost completely absent from regions such as the Sahara Desert and the Antarctic where water is not available for uptake.
Water; however plays an even bigger role in marine habitats. The pH, temperature and salinity of the water in which marine organisms live all play a role in determining what can and cannot live there. A very basic yet extremely prominent example being between the differing organisms in the sea and in freshwater rivers due to the change of salinity.
These are but a few examples of abiotic factors within a habitat, although they are ones which play a very key role in determining which organisms can live within specific regions. The habitats of organisms are more complicated than many people give them credit for, and it is perhaps even more miraculous to observe how perfectly suited organisms have become to such complex habitats.
