Final answer:
A forest fire is an example of density-independent regulation, affecting a population regardless of its density and usually involving abiotic factors.
Step-by-step explanation:
A forest fire is an example of density-independent regulation. This type of regulation refers to factors that affect the mortality of a population regardless of its density. Factors that are density-independent usually involve abiotic factors such as weather events, natural disasters, like forest fires and volcanic eruptions, or pollution. An important characteristic of density-independent factors is that they can affect individuals in a population no matter how crowded (dense) the population is. In the context of a forest fire, it would harm the individuals of a species living in the forest equally, regardless of whether the population is large or small. Hence, it does not depend on the density of the population, unlike density-dependent factors which change in effectiveness based on population density.