What does natural increase refer to in population studies?

Natural increase in population studies refers specifically to the growth in population that occurs when the number of births surpasses the number of deaths within a certain timeframe. This concept emphasizes the intrinsic factors affecting a population, focusing on the biological aspects of population dynamics rather than external factors like immigration or emigration.

In this context, natural increase is a fundamental measure of population change, often used to understand demographic trends and growth potential within a region or country. High natural increase indicates a youthful population and potential for future growth, while low or negative natural increase signals demographic challenges such as aging populations or declining birth rates.

The other options refer to different aspects of population change: emigration decreases population size; immigration addresses growth from external sources rather than the natural increase; and stabilization occurs when births equal deaths, indicating no natural increase, which is not the focus of this term. Thus, the definition of natural increase directly aligns with the growth resulting from the balance of births exceeding deaths.