The biotope is the place or physical environment in which living beings in an ecosystem live. It includes a substrate (soil, water, air, rocks, etc.) and the physical and chemical conditions of that medium (temperature, humidity, luminosity, etc.).
The main environmental factors that determine the physical and chemical characteristics of the biotope are:
- Light. Photosynthetic beings need light and their situation in the ecosystem depends on it.
- Water. It is needed by all organisms, some require a lot of humidity, others less.
- Temperature. There are beings that need warmer temperatures and others that are colder.
- The salinity of the water. Depending on the concentration of dissolved salts in the water, there are organisms that can live in fresh, salty or brackish water.
- The pH. It is the degree of acidity or basicity of the medium.
There is a balance between all the environmental factors that condition the ecosystem, and if one of them varies, the other factors are also affected. For example, if there is a prolonged drought, the soil is not as fertile.
Two different media can be distinguished that characterize the biotope:
- Terrestrial environment. Characterized by the type of soil, degree of humidity, air temperature, amount of light, the substrate on which the organism sits.
- Aquatic environment. Characterized by the degree of salinity of the water (fresh, salty, brackish), by its transparency and luminosity, temperature, amount of gases and dissolved nutrients.