All living organisms interact with each other, with their environment and energy. At the same time, all environmental factors on our planet are quite changeable, therefore, it becomes necessary for all living organisms to sometimes adapt to certain changes, that is, to adapt to new living conditions.
However, there are organisms that are not only able to adapt to the environment, but also adapt the environment to their needs. This ability is called biocontrol of the natural environment.
Any organism on our planet can withstand various changes in influencing factors or the amplitude of factors. This ability is called the ecological valence of a living organism.
The existence of a living organism is possible within a certain range of temperature fluctuations. The most favorable temperature is from 0 ° C to 50 ° C. At the same time, there are organisms that can exist both at lower and higher temperatures.
According to the law of Van’t Hoff (Dutch chemist): with each increase in temperature by 10 ° C, the rate of biogeochemical reactions increases two to three times.
All organisms are divided into two groups depending on their ecological valence:
- Eurybionts are living organisms that can adapt to significant changes in the environment (a bear hibernating in winter, plant seeds in a dry form).
- Stenobionts are organisms that can exist in relatively constant environmental conditions (parasites depend on their host, the koala bear depends on the area of germination of eucalyptus trees).
But for any living organism, there are critical points at which it dies – these are threshold values for changes in environmental factors. Between these values or critical points there is a zone of environmental tolerance or a zone of tension of environmental factors. Near the critical points min (max) are zones of pessimum (zone of discomfort), here the life of living organisms is limited under the influence of external conditions. Next comes the comfort zone, in which the increase in the ecological reactions of organisms is clearly expressed. In the center is the zone of optimum – this is the most suitable zone for the safe life of all organisms.
Environmental factors or limiting factors are factors that restrain the development of certain living organisms.
This happens through a lack or excess of a substance in the ecological environment of a given organism, in comparison with its need for this substance.
As a rule, these factors are referred to as abiogenic factors.
Most often, environmental factors are divided:
- by time – evolutionary, historical, active, modern;
- by frequency – periodic and non-periodic;
- in order of occurrence – primary, secondary;
- by the range of impact – selective, general;
- by the degree of impact – lethal, extreme, limiting, disturbing, mutagenic, teratogenic;
- by origin – abiogenic, biogenic, anthropogenic, natural-anthropogenic, space;
- by the impact environment – atmospheric, water, soil, geological, geomorphological, genetic, physiological, population, biocenotic, ecosystem, biosphere.
