Ecosystems
Physical factors such as light, heat, water, space, minerals, and gases define an ecosystem as well as the biotic factors such as the animals on the food web.
A food web is a diagram that displays the different feeding relationships in an ecosytem
Producers are organisms that produce their own food through photosynthesis. Producers make the food that is used by every other organism higher up the food chain. The producers in Mono Lake are the algae.
Primary producers or first-level consumers eat the producers because they can not make their own food through photosynthesis. Primary producers in Mono Lake are brine shrimp and brine flies.
Secondary consumers or second-level consumers are organisms that eat first level consumers. The birds that visit Mono Lake every year are the secondary consumers because they feed on the trillions of brine shrimp and brine flies in the area.
Third level consumers or tertiary consumers are organisms that eat secondary consumers. In Mono Lake the tertiary consumers are the coyotes because they feed on the secondary consumer birds.
Decomposers are the organisms that eat the dead producers and consumers. In Mono Lake, and in most of the world, bacteria are the main decomposers. Decomposers reduce organisms to their simple chemicals. Then the producers of an ecosystem use these simple chemicals to produce food.
It is important to note that animals are not necessarily associated with a single level. The birds called phalaropes eat both brine shrimp and algae which makes them primary and secondary consumers!