Population Size Answers

Biotic and abiotic limiting factors determine the carrying capacity of an ecosystem by setting the maximum population size the environment can sustainably support. Abiotic factors include non-living resources like water, sunlight, and space, while biotic factors include living interactions such as food availability, predators, and competition. When these factors become limited, population growth slows or stops at the carrying capacity.

Extended drought reduces water availability (a key limiting factor). This lowers plant growth and primary productivity, reduces food and habitat for consumers, intensifies competition for remaining resources, and can raise mortality rates, ultimately decreasing carrying capacity and population size.

Looking at both birth and death rates together is important because they determine the overall population growth rate. A high birth rate with a low death rate leads to population increase, while a low birth rate with a high death rate leads to decline. The difference between the two rates shows whether a population is growing, stable, or shrinking.

Population size is the total number of individuals in a population. Population density is the number of individuals per unit area or volume. Thus, density measures how crowded the population is, while size is simply the count.

Biotic factors include food availability, predation, competition, and disease. Abiotic factors include water, sunlight, temperature, soil nutrients, and space. These factors limit how large a population can grow in an ecosystem.