The four basic processes that result in the fluctuation in the density of the population of a given habitat are natality, mortality, immigration and emigration.
Natality is defined as the birth rate.
Mortality is defined as the death rate.
Immigration is the movement of people inside a particular region.
Emigration is the movement of people out of a particular region.
Final Answer:
Hence, the basic processes are Natality, Mortality, Immigration and Emigration are explained as above.