Any living component that affects another organism, including animals that consume the organism in question, and the living food that the organism consumes.
A plant, fungus, or animal species that is not native to a specific location, which has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health.
The science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products.
The maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment.
Excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.