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Essay on food chain and food web

Food chain

Useful Essay on Food Chain! In nature, we generally distinguish two general types of food chains: The Grazing food chain starts from the living green plants, goes to grazing herbivores that feed on living plant materials with their predatorsand on to carnivores animal eaters. Ecosystems with such type of food chain are directly dependent on an influx of solar radiation. This type of chain thus depends on autotrophic energy capture and the movement of this captured energy to herbivores.

Most of the ecosystems in nature follow this type of food chain. From energy standpoint, these chains are very important. The Detritus Food chain goes from dead organic matter into microorganisms and then to organisms feeding on detritus detritivores and their predators.

Such ecosystems are thus less dependent on direct solar energy. These depend chiefly on the influx of organic matter produced in another system. A good example of a detritus food chain is based on mangrove leaves.

Food web and food chain

All the animals are detritus consumers. These detritivores are the key group of small animals, comprising only a few species but very large number of individuals. They ingest large amounts of the vascular plant detritus. These animals are in turn eaten by some minnows and small game fish etc. The mangroves considered generally as of less economic value make a substantial contribution to the food chain that supports the fisheries, an important economy in that region.

Similarly detritus from sea grasses, salt marsh grasses and seaweeds support fisheries in many estuarine areas.

  1. Ecological pyramids Food webs are, of course, collections of organisms. Biomagnification has become an important issue in ecology because of the presence in the environment of certain human-made substances that can have harmful effects on animals.
  2. Several consumers may eat the same kind of plant or animal for food.
  3. The autotrophs, as mentioned before, convert inorganic compounds into organic compounds. In the figure above the grasshopper is a primary consumer.
  4. Other higher-level consumers are tertiary consumers or third-order consumers, and eat further up on the food web or perhaps on many levels.
  5. For example, if there are 10,000 calories at one level, only 1,000 are transferred to the next. Food Chain A food chain describes how different organisms eat each other, starting out with a plant and ending with an animal.

Thus the detritus food chain ends up in a manner similar to the grazing food chain big fish eat little fishbut the way in which the two chains begin is quite different. In detritus chain, the detritus consumers, in contrast to grazing herbivores, are a mixed group in terms of trophic levels.

These include herbivores, omnivores and primary carnivores. As a group, the detritus feeders obtain some of their energy directly from plant material, most of it secondarily from microorganisms, and some territorially through carnivores for example by eating protozoa or other small invertebrates that have fed or bacteria that have digested plant material.

But under natural situations, system must always be self sufficient. In fact this type of food chain detritus type is simply a sub-component of another ecosystem. And, the above said two types of food chain in nature are indeed linked together belonging to the same ecosystem.