Ecological Pyramid - Definition, importance , types: Pyramid of Number - Pyramid of Biomass & Pyramid of Energy , Drawbacks of Ecological pyramid
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ECOLOGICAL
PYRAMID
MODULE 1
Presentation
Outline
IMPORTANT TERMS
BIOTIC COMPONENTS , FOOD CHAIN, FOOD
WEB & TROPIC LEVELS
ECOLOGICAL PYRAMID
DEFINITION & IMPORTANCE
TYPES OF ECOLOGICAL
PYRAMID
PYRAMID OF ENERGY, PYRAMID OF
NUMBER & PYRAMID OF BIOMASS
1
2
3
4
DRAWBACKS
Biotic Components of Ecosystem
PRODUCERS
CONSUMERS DECOMPOSERS
Plants
Blue Green Algae
etc...
Primary Consumers
Secondary
Consumers
Teritiary Consumers
Earthworms,
Millipedes etc.
What is Food
Chain?
The sequence of transfers of matter
and energy in the form of food from
organism to organism
What is Food Web?
A food web is the natural
interconnection of food chains and a
graphical representation of what-
eats-what in an ecological
community
TROPIC
LEVELS
Organisms occupy a place in the natural surroundings or in a
community according to their feeding relationship with other organisms.
Based on the source of their nutrition or food, organisms occupy a specific
place in the food chain that is known as their trophic level
Definition
ECOLOGICAL
PYRAMID
The graphical representation of
feeding relation between
different organisms in an ecosystem
is called an ecological pyramid.
STRUCTURE
Ecological Pyramid came into
existence due to famous
scientist such as Charles Elton,
G. Evelyn Hutchinson, and
Raymond Lindeman.
It has numerous names like
Eltonian pyramid after Charles
Elton, energy pyramid, trophic
pyramid, and food pyramid.
An ecological pyramid
shows how efficiently
energy is transferred
from one level to the
other and also helps to
quantify energy in a food
chain.
This pyramid also shows
how various organisms in
various ecosystems feed
on each other, highlights
their food patterns and
explains the relationship
between the various levels
within it.
The ecological pyramid also
helps in monitoring the
overall health and condition
of an ecosystem, and helps
in restoring balance. It also
helps to understand how any
further damage to an
ecosystem can be
prevented.
1
2 3
The ecological pyramid is highly significant in an
ecosystem and the reasons are explained below-
IMPORTANCE
There are mainly three types of Ecological Pyramid.:
TYPES OF ECOLOGICAL PYRAMID
PYRAMID
OF
ENERGY
PYRAMID
OF
NUMBER
PYRAMID
OF
BIOMASS
PYRAMID OF
ENERGY
Pyramid of Energy is an upright pyramid that
illustrates the flow of energy from producers
to consumers. Furthermore, it indicates the
actual role played by various organisms in
energy transfer. Energy pyramids indicate
how much energy is required in the next
trophic level as it flows upwards
The pattern of energy flow in this
pyramid can be described based on
the law of thermodynamics
Energy pyramids are
usually slopping
Pyramid of energy is always
upright,
can never be inverted,
Each bar in the energy
pyramid indicates the amount of energy
present at each trophic level in a
given time or annually per unit area.
Energy
Pyramid Based on the flow of energy
ecological pyramid is always upright.
The rate at which food material passes
(in form of energy) through the food chain
determines how energy pyramids are
constructed.
the impression of the
pyramid of energy is
very essential when
describing the idea of
biological magnification.
The pyramid represent
the total numbers of
individuals(population)
present in each trophic
level.
The term “pyramid of
numbers” was first
coined by Elton in 1972.
The number is the
number of
organisms in each
trophic level
In this pyramid the
most abundant
organism occupies the
base and the least
abundant occupies the
apex of the pyramid
PYRAMID
OF
NUMBERS
The pyramid of number is divided into
two different forms depending on the
number of organisms: upright and
inverted.
In the Upright pyramid of numbers, the numbers of
organisms mostly reduce from bottom to top. It usually
occurs in pond and grassland ecosystems where plants
occupy the base of the pyramid. The next levels of the
pyramid include the consumers.
An inverted pyramid is
actually the opposite of
the upright pyramid. It can
closely be observed in tree
ecosystem, where trees
are the producers and
insects are the consumers.
The structure of this
pyramid is partially
inverted or more like a
spindle.
DRAWBACKS
Amongst the three ecosystem
pyramids. The pyramid of number is
the most incorrect, as it does not take
into consideration the exact
population. Hence, it cannot
completely elaborate on the trophic
structure in a system
This pyramid ignores the
biomass of species and it
doesn’t show the energy
transferred between individual
groups.
Pyramids of numbers are not
very functional as they do not
give a clear or true picture of
the food chain.
They do not indicate specifically
the absolute effects of the
geometric, food chain, size
factors of specific organisms.
PYRAMID
OF
BIOMASS
WHAT IS BIOMASS?
Mass is the weight of something so biomass
is the total weight of living matter per unit
area of an ecosystem. We can define
biomass as the amount per unit area
product of the living material existing in an
individual or a number of individuals at in
particular trophic level.
This pyramid indicates the total mass of
organisms in a particular trophic level. .
Biomass consumed by animals mostly is
either converted to living tissue, converted to
energy or remain as undigested products
The pyramid is usually larger at the bottom
but as it goes up it reduces in size and
becomes smaller. There is always a
reduction of biomass with an increase in
trophic level. Approximately 10% to 20% of
the biomass is passed from one trophic level
to the other.
the pyramid of biomass has two forms:
This pyramid can be used to solve the particular issue in the
pyramid of numbers because it shows the exact representation of
the amount of energy present in each trophic level.
When there is a reduction of biomass with a rise in trophic levels,
it signifies wastage and consumption of biomass at every transfer
level.
How do we
benefit from it?
Biomass acts as a source of renewable energy,
replacing fossil fuels. Therefore, helping in
improving climatic conditions as well as being
utilized as fuel reducing wastage and costs.
DRAWBACKS
since it’s actually impossible
to measure the mass of
every single individual. Only
a sample is taken, this leads
to mistakes
Also, the specific time of the
year when data is taken
should be put into
consideration, since
breeding seasons in
different organisms differ.
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DRAWBACKS
3
Sometimes biomass can
indicate energy value,
but it fails to show the
amount of energy
trapped at each energy
level.
LIMITATIONS OF
ECOLOGICAL PYRAMIDS
1.Some organisms such as fungi and
microorganisms have not been given specific
roles in the pyramids despite the fact that
they play a vital role in the ecosystem.
2.These existing pyramids are only
applicable to simple food chains, which
sometimes do not necessarily occur
naturally.
LIMITATIONS OF
ECOLOGICAL PYRAMIDS
3.None, of the three ecological pyramids,
deliver any concept in-relation to variations
in seasons and climates.
4.They also lack to consider the
possibility of the existence of the same
species at different levels