The largest level of organization for organisms is known as an ecosystem. Ecosystems are composed of all of the organisms in an area that interact with one another and their surroundings.
Abiotic factors are nonliving things in an ecosystem that affect organisms. Examples of abiotic factors are things like rain, wind, and temperature.
Biotic factors are living things in an ecosystem that affect organisms. Examples of biotic factors are things like diseases, trees, and food.
All of the lions, trees, deer, fox, grass, rabbits, and squirrels living (biotic) in the Black Hills as well as the temperature, hills, and streams (abiotic).