From;

Kumara . K

2nd year M sc

Rg.no-GP113013

Dos in geography.

Manasagangothri

TO:

DR.P .JAYA SHREE .

Dos in geography.

Manasagangothri

Food from one tropic level reaches to the other tropic level and in this way a chain is establishedthis is called as food chain.

Food chains were first introduced by the African-Arab scientist and philosopher

Al-Jahiz in the 9th century and later popularized in a book published in 1927 by Charles Elton, which also introduced the food web concept.

A food chain is “a sequence of organisms, each of which uses the next, lower member of the sequence as a food source1”

In a food chain each organism obtains energy from the one at the level below.

Plants are called producers because they create their own food through photosynthesis

Animals are consumers because they cannot create their own food, they must eat plants or other animals to get the energy that they need.

Primary producers are “organisms capable of producing their own food”

We can also say that they are photosynthetic, use light energy.

Examples of primary producers include algae, phytoplankton, and large plants.

Primary producers are eaten by primary consumers (herbivores).

Cattails

Marsh

Mallo

w

Blu

e Fl ag

Iris

Marsh

Fern

Four types of consumer ;

Herbivores: animals that eat only plants

Carnivores: animals that eat only other animals.

Omnivores: animals that eat animals and plants.

Detritivores: Animals that eat dead materials and organic wastes

1. Primary Consumers: Herbivores.

2. Secondary Consumers: Carnivores that eat herbivores.

3. Tertiary Consumers: Carnivores that eat other carnivores.

Muskrat (eats mostly Cattails)

Wood Duck eats seeds like those of the Swamp Marsh Mallow and Blue Flag Iris

Glassy-winged Toothpick Grasshopper – eats leaves of plants like cattail and pickerelweed

Black Rat Snake eats eggs of animals like wood duck

Swamp Sparrow eats seeds but also insects like the toothpick grasshopper

Eat other animals in marsh including snake and sparrow.

www.audubon.org

Osprey

A network of food chains or feeding relationships by which energy and nutrients are passed on from one species of living organisms to another.

A food web (or food cycle) is the natural interconnection of food chains and generally a graphical representation (usually an image) of what-eats-what in an ecological community.

A food web is “an interlocking pattern of food chains”

A food web is many food chains linked together to show a more accurate model of all possible feeding relationships of organisms in an ecosystem

A food chain shows how plants and animals get energy from each other. It starts with energy from the sun. A food chain often ends with a predator or an omnivore like humans. Each plant and animals in the chain is important. Many food chains make up a food web. Predators at the end of the food chain die and are eaten by decomposers, which provide soil for producers. Whether it is a food chain or food web, plants and animals need each other. They depend on each other for survival.

DR.P .JAYA SHREE . Professor of geography