Food Web

The Food Web

The food chain consists of four main parts:

The Sun, which provides the energy for everything on the planet (except organisms living near the hydrothermal vents).
Producers: these include all green plants. These are also known as autotrophs, since they make their own food. Producers are able to harness the energy of the sun to make food. In the ocean, the producers are the phytoplankton. It is estimated that 500 billion tons of phytoplankton are produced each year.
Consumers: In short, consumers are every organism that eats something else. They include herbivores (animals that eat plants), carnivores (animals that eat other animals), parasites (animals that live off of other organisms by harming it), and scavengers (animals that eat dead animal carcasses). In the ocean food chain, the zooplankton eat the phytoplankton. These in turn are eaten by larger zooplankton and then by fish. It is estimated that for the 50 billion tons of zooplankton are produced each year which support 200 million tons of fish. Thus, the oceanic food chain is has a low efficiency, since much energy is lost through the 3 to 6 levels of preditory transfer.
Decomposers: These are mainly bacteria and fungi that convert dead matter into gases such as carbon and nitrogen to be released back into the air, soil, or water. Fungi, and other organisms that break down dead organic matter are known as saprophytes. Decomposers are necessary since they recycle the nutrients to be used again by producers.