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FOOD CHAINS AND WEBS
PART - 2
Our Environment
(FOREST ) (GRASSLAND) (POND)
Food Chain In Nature:- (a) Forest(b)Grasslands (c) Pond
The Flow Of Energy Between Various Components Of The Environment Has
Been Extensively Studied And Discovered Some Facts
#1
Very little energy Is available for the next
level of consumers, food chains generally
consist of only three or four steps. The loss of
energy at each step is so great that very little
usable energy remains after four tropic levels.
#2
There are generally a grater number of
individuals at the lower tropic levels of an eco-
system, the greatest number is of the
producers
#3
The length and complexity of food chains vary greatly.
Each organisms generally eaten by two or more other
kinds of organisms which in turn are eaten by several
other organisms. So instead of a straight line food
chain, the relationship can be shown as a series of
branching lines called a food web
FOOD WEB CONSISTING OF MANY FOOD CHAINS
DIAGRAM SHOWING THE ENERGY FLOW IN AN ECOSYSTEM
Review
An interesting aspect of the food chain is how
unknowingly harmful chemicals enter our bodies
through the food chain. One of the reasons is the use
of several pesticides and other chemicals that protect
the crops for from pests. These chemicals are either
washed of into the soil or to the water bodies.
From the soil these are absorbed by plants when they take in water, minerals, and from the water bodies these were taken up by aquatic plants or animals, this is one way how they enter the food chain. As chemicals are not degradable , these get accumulated progressively at each tropic level. As human beings occupy the top level mostly, this phenomenon is commonly known as “BIOLOGICAL MAGNIFICATION”.
END By: Anupam, Ron, Reuben and
Naveen