Population in translation from Latin means "population", "people". Population dynamics is the movement of population, its development, movement. The connected with a concept of ecology, population dynamics is characterized by the certain factors creating changes in the nature and the area. Each population has the leading fitness to various environmental conditions of dwelling.
The set of individuals of one look occupying a certain space and reproducing itself during several generations is and there is population. This definition belongs both to fauna, and to people. In modern ecology treat major factors of population dynamics: number, density, birth rate, mortality, structure and development.
Number – a significant factor which shows how many individuals of any given population occupy a certain space. In this regard it is found out how many natural resources leave on activity of population. In this case it is important to maintain balance of number to avoid sharp ecological and other natural changes on the concrete territory and also for preservation of small populations.
The system of populations of plants, animal and other organisms existing with other populations forms a biocenosis. In relationship between populations each participant of a system is capable to self-control and restoration of the dynamic balance. Also, he uses interpopulation mechanisms which regulate relationship between populations of different types. Density is quantity of individuals per unit area on which this population lives. The number and density – sizes changeable, they periodically change. The birth rate is quantity of the new individuals appearing per unit of time. The fact that not all been born grow further in a full-fledged individual is considered. It is regulation of the nature and external factors. If seeds of any plant sprouted everything to one, then after a while all globe would be covered with this plant. Mortality is a speed of decrease in number of individuals per unit of time owing to a disease, death, a natural death, an old age, a lack of a forage. And development, dynamics, a state and reproduction of populations depend on age and sexual structure of any given population.