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• 2.1 Structure of Eco System

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What is Organism ?
Organism :
• An organism is a fundamental functional
unit in ecology because it interacts
directly with...
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What is Population?
• It refers to the organism of the same
species that are in proximity to one
another
• e.g., A group o...
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What is Community?
• This includes all the populations occupying a
given area.
• The size of the community depends on our
...
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What is species?
• A species is often defined as a group
of organisms capable of interbreeding and
producing fertile offsp...
•

What is habitat? area that
A habitat is an ecological or environmental
is inhabited by particular species of animal, pl...
Biosphere

Ecosystems

Communities

Populations

Organisms
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What is species?
• In biology, a species is one of the basic
units of biological classification .
• A species is often def...
What is habitat?
• A habitat is an ecological or environmental area that is
inhabited by particular species of animal, pla...
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Experts release list of world's 100 most threatened
species

• Seoul, Sept. 11 : International conservation
group has iden...
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• An ecosystem has two basic components

• ABIOTIC COMPONENTS

• BIOTIC COMPONENTS

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•
•
•
•

Biotic Components
Biotic components is classified into
three categories:
PRODUCERS-Autotrophic
CONSUMERS -Heterot...
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• Producers are things such as plants that are fed
off of but do not eat other producers or
organisms.

• Consumers are or...
CONSUMERS

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• A decomposer is an organism of decay.
• These are also called saprobes.
• They break down the remains of dead animals
an...
DECONSUMERS

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PRODUCERS

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What is Abiotic components?
• The non living ,physical and chemical
components of an ecosystem are called the
abiotic fact...
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What is NICHE?
• In ecology, a niche is a term describing the way
of life of a species.
• Each species is thought to have ...
Example for NICHE
• One example is squirrels that collect acorns and bury
them for winter.
• Another is honeybees that gat...
What is Eco System?
• A dynamic complex of plants, animals and
micro organisms inhabiting a particular area
with their non...
Sir Arthur George Tansley (15 August 1871 - 25 November 1955) was
an English botanist who was a pioneer in the science of ...
2.1.3 Identify and explain trophic levels
in food chains and food webs selected
from the local environment.

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What is Trophic levels?
• Trophic levels are the feeding position in a food
chain such as primary producers, herbivore,
pr...
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What is Food chain?
• The feeding of one organism upon another in a
sequence of food transfers is known as a food
chain.
•...
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What is food web?
• In an ecosystem there are many different food
chains and many of these are cross-linked to
form a food...
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phytoplankton

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"Zooplankton" refers to small aquatic animals.

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2.1.4 Explain the principles of pyramids of
numbers, pyramids of biomass, and
pyramids of productivity, and construct
such...
What is Ecological Pyramids?
 Trophic levels and the energy flow from one
level to the next, can be graphically depicted
...
Pyramids of numbers
• A pyramid of numbers is a graphical
representation of the numbers of
individuals in each population ...
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PYRAMID OF NUMBERS represents storages
found at each trophic level.

Units vary

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Grassland
(summer)

Temperate Forest
(summer)
Tertiary consumers
Secondary consumers
Primary consumers
Producers

A few la...
Pyramids of Numbers
Advantages
• Overcomes the problems of pyramids of
number.
Disadvantages
• Only uses samples from popu...
Jayanthi Natarajan
Minister for Environment and Forests

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Pyramid of biomass
• The total amount of living or organic matter
in an ecosystem at any time is called
'Biomass’.
• Pyram...
• Represents the standing stock of each trophic
level (in grams of biomass per unit area g / m2)

• Represent storages alo...
PYRAMID OF BIOMASS represent the
standing stock at each trophic level.

Units:
J m-2

or
g m-2

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Abandoned Field

Ocean
Tertiary consumers

Secondary consumers

Primary consumers

Producers

In open waters of aquatic ec...
How do we get the biomass of a trophic level to
make these pyramids?
•
•
•
•

Take quantitative samples – known area or vo...
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• Analysis of various ecosystems indicates that
those with squat biomass pyramids are less
likely to be disrupted by physi...
Measurement of biomass of different
trophic levels in an ecosystem.

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Describe one method for the measurement of biomass of
different trophic levels in an ecosytem.

• Representative samples o...
Multiply the mean height by the stem density
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• Biomass can be assessed indirectly and
completely non destructively by
• Counting the number of individuals of the targe...
• A more destructive method involves taking a
sample of individuals of the target species and
cutting them at soil level.
...
Think this one………

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IDENTIFY THE ENDANGERED ANIMAL

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Lion Tailed Macaque

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Pyramids of Productivity
• A graphical representation in the shape of
a pyramid showing the distribution of
productivity o...
10 J m-2 yr-1

100 J m-2 yr-1

1,000 J m-2 yr-1
10,000 J m-2 yr-1

producers

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PYRAMID OF PRODUCTIVITY represents
the flow of energy through each trophic level.

Units:

J m-2 yr-1
or

g m-2 yr-1

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Pyramids of productivity
• Flow of energy through trophic levels
• Energy decreases along the food chain
– Lost as heat

•...
• As you move up each trophic level, only
10% of the energy is transferred.
• The other 90% is used for everyday life
func...
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Pyramid structure
affects
the functioning of
an
ecosystem.
Bioaccumulation

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Pyramids of productivity
• Advantages
• Most accurate system shows the actual energy
transferred and allows for rate of pr...
PYRAMID OF STANDING CROP
• Pyramid diagrams may show the fixed quantity
of number, biomass or energy that exists at a
part...
Figure 54.14 Food energy available to the human population at different trophic levels

Efficiency of trophic levels in re...
• ENERGY FLOW THROUGH
• PRODUCERS
• CONSUMERS
• DECOMPOSERS
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Energy Flow through Producers
• Producers convert light energy into chemical
energy of organic molecules
• Energy lost as ...
Energy Flow through Consumers
•
•
•

Obtain energy by eating producers or other
consumers
Energy transfer never above 20% ...
Figure 54.10 Energy partitioning within a link of the food chain

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Energy flow through Decomposers
• Some food is not digested by consumers so
lost as feces to detritivores & saprophytes
• ...
2.1.5 Discuss how the pyramid
structure affects the functioning of an
ecosystem.

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How does pyramid structure effect
ecosystem function?
1. Limited length of food chains
•
•
•

Rarely more than 4 or 5 trop...
What is Biomagnification?
• Biomagnification is the sequence of processes
in an ecosystem by which higher
concentrations o...
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What is bioaccumulation?
• Bioaccumulation refers to the accumulation of
substances, such as pesticides, or other organic
...
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Think this one………

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IDENTIFY THE ENDANGERED ANIMAL

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Blackbu
ck

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• According to the Hindu
mythology blackbuck
or Krishna Jinka is
considered as the
vehicle (vahana) of the
Moon-god Chandr...
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Predation
• In ecology, predation describes a biological
interaction where a predator feeds on its prey.

• Examples :Lion...
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Herbivore
• Herbivores are organisms that are adapted to
eat plants.
• Herbivory is a form of predation in which an
organi...
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Parasitism
• Parasitism is a type of symbiotic relationship
between organisms of different species where
one organism, the...
Mosquito: Females ingest blood for the protein. Male
mosquitos ingest plant juices

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Heartworm of dogs, whose adults reside in the right side of the heart

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Mutualism
• Mutualism is a biological interaction that is
beneficial to both parties.
• Mutualism is the way two organisms...
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2.3.5 APPLY SIMPSON’S DIVERSITY INDEX
AND OUTLINE ITS SIGNIFICANCE

Simpson’s Diversity Index

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Simpson’s Diversity Index
1) Simpson's diversity index (also known as
species diversity index) is one of a number of
diver...
• For plant species the percentage cover in a
square is usually used;
• For animal species, for example in a river, the
nu...
Simpson’s Diversity Index

• Where:
• D = diversity index
N = total number of organisms of all species found
n = number of...
Species

Number of individuals in Number of individuals in
Ecosystem 1
Ecosystem 2

A

23

2

B

28

2

C

22

1

D

27

9...
Simpson’s Diversity Index =
100 x (100 – 1)
[23x(23-1)] + [28x(28-1)] + [22x(22-1)] + [27x(27-1)]
= 4.08

For Ecosystem 2:...
RESULT
• From this it can be seen that ecosystem 1 has
the highest index of diversity.
• The larger then Simpson’s index t...
2.2.2 Abiotic factors in Marine
Ecosystems
Describe and evaluate methods
for measuring at least three
abiotic (physical) f...
Marine Ecosystems

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What are Limiting Factors of an
ecosystem?
• Limiting factors are physical or
biological necessities whose
presence or abs...
Limiting factor fro Marine Ecosytem
•
•
•
•
•

Light
Temperature
Salinity
Dissolved Gases
Pressure

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Light is needed for photosynthesis and
vision.
• Blue light penetrates deepest.

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Temperature
influences the
metabolic rate,
the rate at which
reactions proceed
within an
organism.

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What is the Deepest Part of the Ocean?
• The ocean's deepest area is
the CHALLENGER DEEP (also called the
Marianas Trench)...
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• Most marine organisms are
ECTOTHERMIC having an internal
temperature that stays very close to
that of their surroundings...
Salinity greatly affect cell membranes and
protein structure.
• Disrupts cells osmotic pressure.
• Varies because of rainf...
How deep is the ocean?
The average depth of the ocean is about 4,267
meters (14,000 feet).
The deepest part of the ocean i...
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GASES
Dissolved Gases are necessary for
photosynthesis and respiration.
• CO2 dissolves more easily in water than O2.
• CO...
How deep can humans go
underwater?
• Breathing air, humans can go down around
350 feet without any sort of protection from...
Pressure from the layers of water above.
• Increases with increasing depth.
• To counteract the mass of heavy
muscles and ...
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Marine Zones

• Areas of homogeneous physical
features.
• Usually based on light, temperature,
salinity, depth, latitude, ...
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By light
• Upper zone is called the Euphotic
zone and is where the rate of
photosynthesis is high.

• Lower zone is called...
By Location
Pelagic zone between water and ocean
bottom.
a. Neritic zone = near shore over the
continental shelf

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b. Oceanic zone = deep-water beyond the
continental shelf.
i. Epipelagic = photic zone of the ocean.
ii. Mesopelagic = mid...
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Classifica
tion of
Organism
s

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MEASURING THE ABIOTIC
FACTORS

You should be able to describe & evaluate three
methods in details with references to a nam...
1.TEMPERATURE:-Normally measured using
thermometers or temperature probes attached
to data logger.
Seasonal & diurnal vari...
2.LIGHT INTENSITY:
• This measured using a light meter in lux.
• Seasonal,latitide influence incident the radiation

5/1/2...
3.SOIL:
• Soil organic matter is assessed by baking in the
oven at over 100 degrees to evaporate off the
water and given a...
4.WIND SPEED:
• This is measured using an anemometer; an
instrument with cuts that spin in the wind

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5.SALINITY:
• This measured using refractometer by placing
a droplet of sample water on a lens and
allowing light to enter...
6.PH:
• This measured using universal indicator or a pH
probe
7.Turbidity
• Measured in depth(m) using a sechi
disc(black&...
The Secchi disk measures the transparency of the water. Transparency can be
affected by the color of the water, algae, and...
SPECIES IDENTIFICATION
• This is usually done with a published
identification key.
• The key asks a question and the answe...
(presence/absence of legs;
number of legs;
presence/absence of tentacles;
number of tentacles;
shape;
visible eyes;
bristl...
DIRECT METHODS OF ESTIMATING
OF ABUNDANCE IN ANIMALS
• Animals that don’t move quickly, such as
rocky shore limpets or gra...
2.3.2 Abundance of organisms.

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Methods for Estimating Population Size

1. Quadrats
2. Capture/Mark/Release/Recapture (Lincoln
Index)

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Why we should know the population size of
an ecosystem?
• Knowing population size is important in
making environmental dec...
• ESTIMATING THE
POPULATION USING THE
NETS

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1.Freshwater nets for lake and stream
invertebrates

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2.Sweep nets for grassland and scrub

Sweep nets are sturdy nets used to collect
insects from long grass.
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4.Pit trapping and baited traps for terrestrial
invertebrates

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5.Beating trays for invertebrates in trees

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• When estimating population size it is
important to collect RANDOM
SAMPLES.
• A sample is a part of a population, part of...
• Quadrats METHOD

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Using Quadrats
1. Mark out area to be sampled.
2. Place quadrates ( 1 m2, 10 m2) randomly
within the area.
3. Count how ma...
SYSTEMATIC
QUDRATS

RANDOM
QUDRATS

Quadrat sampling is suitable for
plants that do not move around and
are easy to find.
...
Quadrat method can be used to determine:
 POPULATION DENSITY = number of
individuals of each species per area.
 PERCENTA...
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Capture/Mark/
Release/Recapture

Lincoln index
1. Capture as many individuals as possible in the
area occupied by the anim...
3. Release all the marked individuals and allow
them to settle back into their habitat.
4. Recapture as many individuals a...
Capture and Marking

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Assumptions:
1. The population of organisms must be closed, with
no immigration or emigration.
2. The time between samples...
5. Calculate the estimated population size by
using the Lincoln Index:
population size = N1 X N2
N3
N1 = number caught and...
• Next unit is continuing in the another
PowerPoint presentation

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Ecosystem powerpoint 1

  1. 1. 5/1/2013 AUTHOR-GURU IB/ESS 1
  2. 2. • 2.1 Structure of Eco System 5/1/2013 AUTHOR-GURU IB/ESS 2
  3. 3. What is Organism ? Organism : • An organism is a fundamental functional unit in ecology because it interacts directly with the environment as well as with other organism e.g., Rabbits 5/1/2013 AUTHOR-GURU IB/ESS 3
  4. 4. 5/1/2013 AUTHOR-GURU IB/ESS 4
  5. 5. What is Population? • It refers to the organism of the same species that are in proximity to one another • e.g., A group of rabbit 5/1/2013 AUTHOR-GURU IB/ESS 5
  6. 6. 5/1/2013 AUTHOR-GURU IB/ESS 6
  7. 7. What is Community? • This includes all the populations occupying a given area. • The size of the community depends on our scale of reference • The community and the non-living environment together are referred to as an ECOLOGICAL SYSTEM or ECOSYSTEM • e.g., pond fish and plants 5/1/2013 AUTHOR-GURU IB/ESS 7
  8. 8. 5/1/2013 AUTHOR-GURU IB/ESS 8
  9. 9. 5/1/2013 AUTHOR-GURU IB/ESS 9
  10. 10. What is species? • A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. 5/1/2013 AUTHOR-GURU IB/ESS 10
  11. 11. • What is habitat? area that A habitat is an ecological or environmental is inhabited by particular species of animal, plant or other type of organism. • It is the natural environment in which an organism lives, or the physical environment that surrounds a species population. 5/1/2013 AUTHOR-GURU IB/ESS 11
  12. 12. Biosphere Ecosystems Communities Populations Organisms 5/1/2013 AUTHOR-GURU IB/ESS 12
  13. 13. What is species? • In biology, a species is one of the basic units of biological classification . • A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. 5/1/2013 AUTHOR-GURU IB/ESS 13
  14. 14. What is habitat? • A habitat is an ecological or environmental area that is inhabited by particular species of animal, plant or other type of organism. • It is the natural environment in which an organism lives, or the physical environment that surrounds a species population. 5/1/2013 AUTHOR-GURU IB/ESS 14
  15. 15. 5/1/2013 AUTHOR-GURU IB/ESS 15
  16. 16. Experts release list of world's 100 most threatened species • Seoul, Sept. 11 : International conservation group has identified a list of the earth's most threatened 100 animals, plants and fungi and have called for an urgent need to protect them. • The species have been identified by more than 8,000 scientists from the IUCN Species Survival Commission (IUCN SSC), but they fear they will be allowed to die because none of these species provide humans with any benefits. 5/1/2013 AUTHOR-GURU IB/ESS 16
  17. 17. 5/1/2013 AUTHOR-GURU IB/ESS 17
  18. 18. • An ecosystem has two basic components • ABIOTIC COMPONENTS • BIOTIC COMPONENTS 5/1/2013 AUTHOR-GURU IB/ESS 18
  19. 19. • • • • Biotic Components Biotic components is classified into three categories: PRODUCERS-Autotrophic CONSUMERS -Heterotrophic DECOMPOSERS OR SAPTROTROPHS 5/1/2013 AUTHOR-GURU IB/ESS 19
  20. 20. 5/1/2013 AUTHOR-GURU IB/ESS 20
  21. 21. • Producers are things such as plants that are fed off of but do not eat other producers or organisms. • Consumers are organisms (including us humans) that get their energy from producers, regarding the flow of energy through an ecosystem 5/1/2013 AUTHOR-GURU IB/ESS 21
  22. 22. CONSUMERS 5/1/2013 AUTHOR-GURU IB/ESS 22
  23. 23. • A decomposer is an organism of decay. • These are also called saprobes. • They break down the remains of dead animals and plants, releasing the substances that can be used by other members of the ecosystem 5/1/2013 AUTHOR-GURU IB/ESS 23
  24. 24. DECONSUMERS 5/1/2013 AUTHOR-GURU IB/ESS 24
  25. 25. PRODUCERS 5/1/2013 AUTHOR-GURU IB/ESS 25
  26. 26. 5/1/2013 AUTHOR-GURU IB/ESS 26
  27. 27. What is Abiotic components? • The non living ,physical and chemical components of an ecosystem are called the abiotic factors and include: • Light • Temperature, • Water, • Soil • The atmosphere • Climate –Light intensity, temperature range, precipitation 5/1/2013 AUTHOR-GURU IB/ESS 27
  28. 28. 5/1/2013 AUTHOR-GURU IB/ESS 28
  29. 29. What is NICHE? • In ecology, a niche is a term describing the way of life of a species. • Each species is thought to have a separate, unique niche. • The ecological niche describes how an organism or population responds to the distribution of resources and competitors 5/1/2013 AUTHOR-GURU IB/ESS 29
  30. 30. Example for NICHE • One example is squirrels that collect acorns and bury them for winter. • Another is honeybees that gather nectar from flowers to make honey. • Other organisms that may exist in the same environment don't do this. • For instance, a bird may live in the same tree as a beehive, but the bird does not make honey the way the bees do. That is not its niche. 5/1/2013 AUTHOR-GURU IB/ESS 30
  31. 31. What is Eco System? • A dynamic complex of plants, animals and micro organisms inhabiting a particular area with their non living environment interacting as a functional unit 5/1/2013 AUTHOR-GURU IB/ESS 31
  32. 32. Sir Arthur George Tansley (15 August 1871 - 25 November 1955) was an English botanist who was a pioneer in the science of ecology 5/1/2013 AUTHOR-GURU IB/ESS 32
  33. 33. 2.1.3 Identify and explain trophic levels in food chains and food webs selected from the local environment. 5/1/2013 AUTHOR-GURU IB/ESS 33
  34. 34. What is Trophic levels? • Trophic levels are the feeding position in a food chain such as primary producers, herbivore, primary carnivore, etc. • Green plants form the first trophic level, the producers. • Herbivores form the second trophic level, while carnivores form the third and even the fourth trophic levels. 5/1/2013 AUTHOR-GURU IB/ESS 34
  35. 35. 5/1/2013 AUTHOR-GURU IB/ESS 35
  36. 36. 5/1/2013 AUTHOR-GURU IB/ESS 36
  37. 37. What is Food chain? • The feeding of one organism upon another in a sequence of food transfers is known as a food chain. • Food chain is the chain of transfer of energy from one organism to another. A simple food chain is like the following: • rose plant -- aphids -- beetle -- chameleon -hawk. 5/1/2013 AUTHOR-GURU IB/ESS 37
  38. 38. 5/1/2013 AUTHOR-GURU IB/ESS 38
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  45. 45. 5/1/2013 AUTHOR-GURU IB/ESS 45
  46. 46. What is food web? • In an ecosystem there are many different food chains and many of these are cross-linked to form a food web. • Ultimately all plants and animals in an ecosystem are part of this complex food web. 5/1/2013 AUTHOR-GURU IB/ESS 46
  47. 47. 5/1/2013 AUTHOR-GURU IB/ESS 47
  48. 48. 5/1/2013 AUTHOR-GURU IB/ESS 48
  49. 49. 5/1/2013 AUTHOR-GURU IB/ESS 49
  50. 50. 5/1/2013 AUTHOR-GURU IB/ESS 50
  51. 51. 5/1/2013 AUTHOR-GURU IB/ESS 51
  52. 52. phytoplankton 5/1/2013 AUTHOR-GURU IB/ESS 52
  53. 53. 5/1/2013 AUTHOR-GURU IB/ESS 53
  54. 54. "Zooplankton" refers to small aquatic animals. 5/1/2013 AUTHOR-GURU IB/ESS 54
  55. 55. 5/1/2013 AUTHOR-GURU IB/ESS 55
  56. 56. 5/1/2013 AUTHOR-GURU IB/ESS 56
  57. 57. 2.1.4 Explain the principles of pyramids of numbers, pyramids of biomass, and pyramids of productivity, and construct such pyramids from given data. 5/1/2013 AUTHOR-GURU IB/ESS 57
  58. 58. What is Ecological Pyramids?  Trophic levels and the energy flow from one level to the next, can be graphically depicted using an ecological pyramid.  Three types of ecological pyramids can usually be distinguished namely: 1. Pyramids of numbers 2. Pyramid of biomass 3. Pyramids of productivity 5/1/2013 AUTHOR-GURU IB/ESS 58
  59. 59. Pyramids of numbers • A pyramid of numbers is a graphical representation of the numbers of individuals in each population in a food chain. • A pyramid of numbers can be used to examine how the population of a certain species affects another 5/1/2013 AUTHOR-GURU IB/ESS 59
  60. 60. 5/1/2013 AUTHOR-GURU IB/ESS 60
  61. 61. PYRAMID OF NUMBERS represents storages found at each trophic level. Units vary 5/1/2013 AUTHOR-GURU IB/ESS 61
  62. 62. 5/1/2013 AUTHOR-GURU IB/ESS 62
  63. 63. 5/1/2013 AUTHOR-GURU IB/ESS 63
  64. 64. 5/1/2013 AUTHOR-GURU IB/ESS 64
  65. 65. Grassland (summer) Temperate Forest (summer) Tertiary consumers Secondary consumers Primary consumers Producers A few large producers (the trees) support a much larger number of Small primary consumers (insects) that feed on the trees. 5/1/2013 AUTHOR-GURU IB/ESS 65
  66. 66. Pyramids of Numbers Advantages • Overcomes the problems of pyramids of number. Disadvantages • Only uses samples from populations, so it is impossible to measure biomass exactly. also the time of the year that biomass is measured affects the result. 5/1/2013 AUTHOR-GURU IB/ESS 66
  67. 67. Jayanthi Natarajan Minister for Environment and Forests 5/1/2013 AUTHOR-GURU IB/ESS 67
  68. 68. Pyramid of biomass • The total amount of living or organic matter in an ecosystem at any time is called 'Biomass’. • Pyramid of biomass is the graphic representation of biomass present per unit area of different tropic levels, with producers at the base and top carnivores at the tip". 5/1/2013 AUTHOR-GURU IB/ESS 68
  69. 69. • Represents the standing stock of each trophic level (in grams of biomass per unit area g / m2) • Represent storages along with pyramids of numbers 5/1/2013 AUTHOR-GURU IB/ESS 69
  70. 70. PYRAMID OF BIOMASS represent the standing stock at each trophic level. Units: J m-2 or g m-2 5/1/2013 AUTHOR-GURU IB/ESS 70
  71. 71. 5/1/2013 AUTHOR-GURU IB/ESS 71
  72. 72. 5/1/2013 AUTHOR-GURU IB/ESS 72
  73. 73. Abandoned Field Ocean Tertiary consumers Secondary consumers Primary consumers Producers In open waters of aquatic ecosystems, the biomass primary consumers (zooplankton) can exceed that of producers. The zooplankton eat the Producers (phytoplankton) as fast as they reproduce, so their population is never very large. 5/1/2013 AUTHOR-GURU IB/ESS 73
  74. 74. How do we get the biomass of a trophic level to make these pyramids? • • • • Take quantitative samples – known area or volume Measure the whole habitat size Dry samples to remove water weight Take Dry mass for sample then extrapolate to entire trophic level • Evaluation  It is an estimate based on assumption that – all individuals at that trophic level are the same – The sample accurately represents the whole habitat 5/1/2013 AUTHOR-GURU IB/ESS 74
  75. 75. 5/1/2013 AUTHOR-GURU IB/ESS 75
  76. 76. 5/1/2013 AUTHOR-GURU IB/ESS 76
  77. 77. • Analysis of various ecosystems indicates that those with squat biomass pyramids are less likely to be disrupted by physical or biotic changes than those with tall, skinny pyramids (having conversion efficiencies less than 10%). 5/1/2013 AUTHOR-GURU IB/ESS 77
  78. 78. Measurement of biomass of different trophic levels in an ecosystem. 5/1/2013 AUTHOR-GURU IB/ESS 78
  79. 79. Describe one method for the measurement of biomass of different trophic levels in an ecosytem. • Representative samples of all living organisms in the ecosystem are collected, for example from randomly positioned quadrats. • The organisms are dried, by being placed in an oven at 60-80 C. • The mass of organisms in each trophic level is measured using an electronic balance. 5/1/2013 AUTHOR-GURU IB/ESS 79
  80. 80. Multiply the mean height by the stem density 5/1/2013 AUTHOR-GURU IB/ESS 80
  81. 81. • Biomass can be assessed indirectly and completely non destructively by • Counting the number of individuals of the target speices • Randomly selecting a sample of individuals • Determining mean height within the sample (height will be an indirect measure of biomass) • Multiply the mean height by the stem density (number of individuals) 5/1/2013 AUTHOR-GURU IB/ESS 81
  82. 82. • A more destructive method involves taking a sample of individuals of the target species and cutting them at soil level. • Tag each individual with a label, dry it to a stable weight and weigh it. • Determine the mean mass of the plants in the area and multiply by the stem density in the area. 5/1/2013 AUTHOR-GURU IB/ESS 82
  83. 83. Think this one……… 5/1/2013 AUTHOR-GURU IB/ESS 83
  84. 84. IDENTIFY THE ENDANGERED ANIMAL 5/1/2013 AUTHOR-GURU IB/ESS 84
  85. 85. Lion Tailed Macaque 5/1/2013 AUTHOR-GURU IB/ESS 85
  86. 86. Pyramids of Productivity • A graphical representation in the shape of a pyramid showing the distribution of productivity or flow of energy through the tropic levels. 5/1/2013 AUTHOR-GURU IB/ESS 86
  87. 87. 10 J m-2 yr-1 100 J m-2 yr-1 1,000 J m-2 yr-1 10,000 J m-2 yr-1 producers 5/1/2013 AUTHOR-GURU IB/ESS 87
  88. 88. 5/1/2013 AUTHOR-GURU IB/ESS 88
  89. 89. PYRAMID OF PRODUCTIVITY represents the flow of energy through each trophic level. Units: J m-2 yr-1 or g m-2 yr-1 5/1/2013 AUTHOR-GURU IB/ESS 89
  90. 90. Pyramids of productivity • Flow of energy through trophic levels • Energy decreases along the food chain – Lost as heat • Productivity pyramids ALWAYS decrease as they go higher – 1st and 2nd laws of thermodynamics • Shows rate at which stock is generated at each level • Productivity measured in units of flow (J / m2 yr or g / m2 yr ) Joule per square metre in year/ 5/1/2013 AUTHOR-GURU IB/ESS 90
  91. 91. • As you move up each trophic level, only 10% of the energy is transferred. • The other 90% is used for everyday life functions, metabolism. 5/1/2013 AUTHOR-GURU IB/ESS 91
  92. 92. 5/1/2013 AUTHOR-GURU IB/ESS 92
  93. 93. Pyramid structure affects the functioning of an ecosystem. Bioaccumulation 5/1/2013 AUTHOR-GURU IB/ESS 93
  94. 94. 5/1/2013 AUTHOR-GURU IB/ESS 94
  95. 95. Pyramids of productivity • Advantages • Most accurate system shows the actual energy transferred and allows for rate of production. • Disadvantages • It is very difficult and complex to collect energy data. 5/1/2013 AUTHOR-GURU IB/ESS 95
  96. 96. PYRAMID OF STANDING CROP • Pyramid diagrams may show the fixed quantity of number, biomass or energy that exists at a particular time in a given area or averaged from many of these measurements. • This is termed STANDING CROP. • The unit would be number,dry biomass or energy kg/m2 or J/m3. 5/1/2013 AUTHOR-GURU IB/ESS 96
  97. 97. Figure 54.14 Food energy available to the human population at different trophic levels Efficiency of trophic levels in relation to the total energy available decreases with higher numbers But efficiency of transfer always remains around that 10% rule 5/1/2013 AUTHOR-GURU IB/ESS 97
  98. 98. • ENERGY FLOW THROUGH • PRODUCERS • CONSUMERS • DECOMPOSERS 5/1/2013 AUTHOR-GURU IB/ESS 98
  99. 99. Energy Flow through Producers • Producers convert light energy into chemical energy of organic molecules • Energy lost as cell respiration in producers then as heat elsewhere • When consumers eat producers energy passes on to them • In death organic matter passes to saprophytes & detritivores 5/1/2013 AUTHOR-GURU IB/ESS 99
  100. 100. Energy Flow through Consumers • • • Obtain energy by eating producers or other consumers Energy transfer never above 20% efficient, usually between 10 – 20% Food ingested has multiple fates 1. Large portion used in cell respiration for meeting energy requirements (LOSS) 2. Smaller portion is assimilated used for growth, repair, reproduction 3. Smallest portion, undigested material excreted as waste (LOSS) AUTHOR-GURU 5/1/2013 IB/ESS 100
  101. 101. Figure 54.10 Energy partitioning within a link of the food chain 5/1/2013 AUTHOR-GURU IB/ESS 101
  102. 102. Energy flow through Decomposers • Some food is not digested by consumers so lost as feces to detritivores & saprophytes • Energy eventually released by process of cell respiration or lost as heat 5/1/2013 AUTHOR-GURU IB/ESS 102
  103. 103. 2.1.5 Discuss how the pyramid structure affects the functioning of an ecosystem. 5/1/2013 AUTHOR-GURU IB/ESS 103
  104. 104. How does pyramid structure effect ecosystem function? 1. Limited length of food chains • • • Rarely more than 4 or 5 trophic levels Not enough energy left after 4-5 transfers to support organisms feeding high up Possible exception marine/aquatic systems b/c first few levels small and little structure 2. Vulnerability of top carnivores • • • 5/1/2013 Effected by changes at all lower levels Small numbers to begin with Effected by pollutants & toxins passed through system AUTHOR-GURU IB/ESS 104
  105. 105. What is Biomagnification? • Biomagnification is the sequence of processes in an ecosystem by which higher concentrations of a particular chemical, such as the pesticide DDT, are reached in organisms higher up the food chain, generally through a series of prey-predator relationships. 5/1/2013 AUTHOR-GURU IB/ESS 105
  106. 106. 5/1/2013 AUTHOR-GURU IB/ESS 106
  107. 107. 5/1/2013 AUTHOR-GURU IB/ESS 107
  108. 108. What is bioaccumulation? • Bioaccumulation refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. • Bioaccumulation occurs when an organism absorbs a toxic substance at a rate greater than that at which the substance is lost. 5/1/2013 AUTHOR-GURU IB/ESS 108
  109. 109. 5/1/2013 AUTHOR-GURU IB/ESS 109
  110. 110. 5/1/2013 AUTHOR-GURU IB/ESS 110
  111. 111. Think this one……… 5/1/2013 AUTHOR-GURU IB/ESS 111
  112. 112. IDENTIFY THE ENDANGERED ANIMAL 5/1/2013 AUTHOR-GURU IB/ESS 112
  113. 113. Blackbu ck 5/1/2013 AUTHOR-GURU IB/ESS 113
  114. 114. • According to the Hindu mythology blackbuck or Krishna Jinka is considered as the vehicle (vahana) of the Moon-god Chandrama. 5/1/2013 Akbar Hunting Black BuckAkbarnama AUTHOR-GURU IB/ESS 114
  115. 115. 5/1/2013 AUTHOR-GURU IB/ESS 115
  116. 116. Predation • In ecology, predation describes a biological interaction where a predator feeds on its prey. • Examples :Lion killing buffalo, Eagle killing Rabbit, Mantis eating a bee. 5/1/2013 AUTHOR-GURU IB/ESS 116
  117. 117. 5/1/2013 AUTHOR-GURU IB/ESS 117
  118. 118. 5/1/2013 AUTHOR-GURU IB/ESS 118
  119. 119. Herbivore • Herbivores are organisms that are adapted to eat plants. • Herbivory is a form of predation in which an organism consumes principally autotrophs such as plants, algae and photosynthesizing bacteria. 5/1/2013 AUTHOR-GURU IB/ESS 119
  120. 120. 5/1/2013 AUTHOR-GURU IB/ESS 120
  121. 121. Parasitism • Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the host. Example : • Mosquito: Females ingest blood for the protein. Male mosquitos ingest plant juices. • Heartworm of dogs, whose adults reside in the right side of the heart 5/1/2013 AUTHOR-GURU IB/ESS 121
  122. 122. Mosquito: Females ingest blood for the protein. Male mosquitos ingest plant juices 5/1/2013 AUTHOR-GURU IB/ESS 122
  123. 123. Heartworm of dogs, whose adults reside in the right side of the heart 5/1/2013 AUTHOR-GURU IB/ESS 123
  124. 124. Mutualism • Mutualism is a biological interaction that is beneficial to both parties. • Mutualism is the way two organisms biologically interact where each individual derives a fitness benefit (i.e. increased survivorship). • Examples :Clownfish and sea anemones, langur monkey curing cow's ear 5/1/2013 AUTHOR-GURU IB/ESS 124
  125. 125. 5/1/2013 AUTHOR-GURU IB/ESS 125
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  127. 127. 2.3.5 APPLY SIMPSON’S DIVERSITY INDEX AND OUTLINE ITS SIGNIFICANCE Simpson’s Diversity Index 5/1/2013 AUTHOR-GURU IB/ESS 127
  128. 128. Simpson’s Diversity Index 1) Simpson's diversity index (also known as species diversity index) is one of a number of diversity indices, used to measure diversity. 2) In ecology, it is often used to quantify the biodiversity of a habitat. 3) It takes into account the number of species present, as well as the relative abundance of each species. 4) The Simpson index represents the probability that two randomly selected individuals in the habitat will not belong to the same species. 5/1/2013 AUTHOR-GURU IB/ESS 128
  129. 129. • For plant species the percentage cover in a square is usually used; • For animal species, for example in a river, the number of organisms of a species is used. • The reason percentage cover is used is because it is usually very difficult to count all the individual plants 5/1/2013 AUTHOR-GURU IB/ESS 129
  130. 130. Simpson’s Diversity Index • Where: • D = diversity index N = total number of organisms of all species found n = number of individuals of a particular species 5/1/2013 AUTHOR-GURU IB/ESS 130
  131. 131. Species Number of individuals in Number of individuals in Ecosystem 1 Ecosystem 2 A 23 2 B 28 2 C 22 1 D 27 93 Total individuals in ecosystem 100 98 5/1/2013 AUTHOR-GURU IB/ESS 131
  132. 132. Simpson’s Diversity Index = 100 x (100 – 1) [23x(23-1)] + [28x(28-1)] + [22x(22-1)] + [27x(27-1)] = 4.08 For Ecosystem 2: Simpson’s Diversity Index = 98 x (98 – 1) [2x(2-1)] + [2x(2-1)] + [1x(1-1)] + [93x(93-1)] = 1.11 5/1/2013 AUTHOR-GURU IB/ESS 132
  133. 133. RESULT • From this it can be seen that ecosystem 1 has the highest index of diversity. • The larger then Simpson’s index the more diverse. • Increasing diversity tends to suggest more stable ecosystems with more connections within them. 5/1/2013 AUTHOR-GURU IB/ESS 133
  134. 134. 2.2.2 Abiotic factors in Marine Ecosystems Describe and evaluate methods for measuring at least three abiotic (physical) factors within an ecosystem. 5/1/2013 AUTHOR-GURU IB/ESS 134
  135. 135. Marine Ecosystems 5/1/2013 AUTHOR-GURU IB/ESS 135
  136. 136. What are Limiting Factors of an ecosystem? • Limiting factors are physical or biological necessities whose presence or absence in inappropriate amounts limits the normal action of the organism. 5/1/2013 AUTHOR-GURU IB/ESS 136
  137. 137. Limiting factor fro Marine Ecosytem • • • • • Light Temperature Salinity Dissolved Gases Pressure 5/1/2013 AUTHOR-GURU IB/ESS 137
  138. 138. Light is needed for photosynthesis and vision. • Blue light penetrates deepest. 5/1/2013 AUTHOR-GURU IB/ESS 138
  139. 139. Temperature influences the metabolic rate, the rate at which reactions proceed within an organism. 5/1/2013 AUTHOR-GURU IB/ESS 139
  140. 140. What is the Deepest Part of the Ocean? • The ocean's deepest area is the CHALLENGER DEEP (also called the Marianas Trench), which is about 11 km (almost 7 miles, or almost 36,000 feet) deep. • The trench is 1,554 miles long and 44 miles wide, 5/1/2013 AUTHOR-GURU IB/ESS 140
  141. 141. 5/1/2013 AUTHOR-GURU IB/ESS 141
  142. 142. • Most marine organisms are ECTOTHERMIC having an internal temperature that stays very close to that of their surroundings. • A few complex animals (mammals & birds) are ENDOTHERMIC, meaning they maintain a stable internal temperature. • Ocean temperature varies in both depth and latitude. • Ocean temperatures vary less than on land. 5/1/2013 AUTHOR-GURU IB/ESS 142
  143. 143. Salinity greatly affect cell membranes and protein structure. • Disrupts cells osmotic pressure. • Varies because of rainfall, evaporation and runoff from land. 5/1/2013 AUTHOR-GURU IB/ESS 143
  144. 144. How deep is the ocean? The average depth of the ocean is about 4,267 meters (14,000 feet). The deepest part of the ocean is called the Challenger Deep and is located beneath the western Pacific Ocean in the southern end of the Mariana Trench, which runs several hundred kilometers southwest of the U.S. territorial island of Guam. Challenger Deep is approximately 11,030 meters (36,200 feet) deep. 5/1/2013 AUTHOR-GURU IB/ESS 144
  145. 145. 5/1/2013 AUTHOR-GURU IB/ESS 145
  146. 146. 5/1/2013 AUTHOR-GURU IB/ESS 146
  147. 147. GASES Dissolved Gases are necessary for photosynthesis and respiration. • CO2 dissolves more easily in water than O2. • CO2 is more abundant in deep waters than surface water. • O2 decrease dramatically where light penetration decreases. 5/1/2013 AUTHOR-GURU IB/ESS 147
  148. 148. How deep can humans go underwater? • Breathing air, humans can go down around 350 feet without any sort of protection from pressure • Utilizing mixed gases, a diver can reach a little over 300 meters 5/1/2013 AUTHOR-GURU IB/ESS 148
  149. 149. Pressure from the layers of water above. • Increases with increasing depth. • To counteract the mass of heavy muscles and bone, many swimming fishes have gas-filled bladders. • Deep-sea fish don’t have gas bladders, but light bones and oily watery flesh. 5/1/2013 AUTHOR-GURU IB/ESS 149
  150. 150. 5/1/2013 AUTHOR-GURU IB/ESS 150
  151. 151. Marine Zones • Areas of homogeneous physical features. • Usually based on light, temperature, salinity, depth, latitude, behavior and/or water density. 5/1/2013 AUTHOR-GURU IB/ESS 151
  152. 152. 5/1/2013 AUTHOR-GURU IB/ESS 152
  153. 153. 5/1/2013 AUTHOR-GURU IB/ESS 153
  154. 154. By light • Upper zone is called the Euphotic zone and is where the rate of photosynthesis is high. • Lower zone is called Disphotic zone and is where organisms can see, but there is sufficient light for photosynthesis. Aphotic zone where no light penetrates. 5/1/2013 AUTHOR-GURU IB/ESS 154
  155. 155. By Location Pelagic zone between water and ocean bottom. a. Neritic zone = near shore over the continental shelf 5/1/2013 AUTHOR-GURU IB/ESS 155
  156. 156. b. Oceanic zone = deep-water beyond the continental shelf. i. Epipelagic = photic zone of the ocean. ii. Mesopelagic = middle ocean waters. iii. Bathypelagic = ocean floor. iv. Abyssopelagic = deep-ocean trenches. 5/1/2013 AUTHOR-GURU IB/ESS 156
  157. 157. 5/1/2013 AUTHOR-GURU IB/ESS 157
  158. 158. Classifica tion of Organism s 5/1/2013 AUTHOR-GURU IB/ESS 158
  159. 159. 5/1/2013 AUTHOR-GURU IB/ESS 159
  160. 160. 5/1/2013 AUTHOR-GURU IB/ESS 160
  161. 161. 5/1/2013 AUTHOR-GURU IB/ESS 161
  162. 162. MEASURING THE ABIOTIC FACTORS You should be able to describe & evaluate three methods in details with references to a named ecosystem 5/1/2013 AUTHOR-GURU IB/ESS 162
  163. 163. 1.TEMPERATURE:-Normally measured using thermometers or temperature probes attached to data logger. Seasonal & diurnal variations important ,as is the influence of aspect 5/1/2013 AUTHOR-GURU IB/ESS 163
  164. 164. 2.LIGHT INTENSITY: • This measured using a light meter in lux. • Seasonal,latitide influence incident the radiation 5/1/2013 AUTHOR-GURU IB/ESS 164
  165. 165. 3.SOIL: • Soil organic matter is assessed by baking in the oven at over 100 degrees to evaporate off the water and given as percentage of original soil mass 5/1/2013 AUTHOR-GURU IB/ESS 165
  166. 166. 4.WIND SPEED: • This is measured using an anemometer; an instrument with cuts that spin in the wind 5/1/2013 AUTHOR-GURU IB/ESS 166
  167. 167. 5.SALINITY: • This measured using refractometer by placing a droplet of sample water on a lens and allowing light to enter through the water 5/1/2013 AUTHOR-GURU IB/ESS 167
  168. 168. 6.PH: • This measured using universal indicator or a pH probe 7.Turbidity • Measured in depth(m) using a sechi disc(black& white decorated disc) lowered on a measuring rope until it is no longer visible 5/1/2013 AUTHOR-GURU IB/ESS 168
  169. 169. The Secchi disk measures the transparency of the water. Transparency can be affected by the color of the water, algae, and suspended sediments. Transparency decreases as color, suspended sediments, or algal abundance increases. 5/1/2013 AUTHOR-GURU IB/ESS 169
  170. 170. SPECIES IDENTIFICATION • This is usually done with a published identification key. • The key asks a question and the answer determines what step to go to next, either the name of the species or another question 5/1/2013 AUTHOR-GURU IB/ESS 170
  171. 171. (presence/absence of legs; number of legs; presence/absence of tentacles; number of tentacles; shape; visible eyes; bristles 5/1/2013 AUTHOR-GURU IB/ESS 171
  172. 172. DIRECT METHODS OF ESTIMATING OF ABUNDANCE IN ANIMALS • Animals that don’t move quickly, such as rocky shore limpets or grassland snails, can be counted in quadrats giving a direct measure of population density. • This only suitable for species that don’t run away • A variety of direct sampling techniques can be used to collect invertebrates using nets and traps 5/1/2013 AUTHOR-GURU IB/ESS 172
  173. 173. 2.3.2 Abundance of organisms. 5/1/2013 AUTHOR-GURU IB/ESS 173
  174. 174. Methods for Estimating Population Size 1. Quadrats 2. Capture/Mark/Release/Recapture (Lincoln Index) 5/1/2013 AUTHOR-GURU IB/ESS 174
  175. 175. Why we should know the population size of an ecosystem? • Knowing population size is important in making environmental decisions that would affect the population. • Making a decision on an estimate that is too high  extinction. • Making a decision on an estimate that is too low  unnecessarily hurt people that depend on the animals for food & income. 5/1/2013 AUTHOR-GURU IB/ESS 175
  176. 176. • ESTIMATING THE POPULATION USING THE NETS 5/1/2013 AUTHOR-GURU IB/ESS 176
  177. 177. 5/1/2013 AUTHOR-GURU IB/ESS 177
  178. 178. 1.Freshwater nets for lake and stream invertebrates 5/1/2013 AUTHOR-GURU IB/ESS 178
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  182. 182. 2.Sweep nets for grassland and scrub Sweep nets are sturdy nets used to collect insects from long grass. 5/1/2013 AUTHOR-GURU IB/ESS 182
  183. 183. 5/1/2013 AUTHOR-GURU IB/ESS 183
  184. 184. 5/1/2013 AUTHOR-GURU IB/ESS 184
  185. 185. 4.Pit trapping and baited traps for terrestrial invertebrates 5/1/2013 AUTHOR-GURU IB/ESS 185
  186. 186. 5/1/2013 AUTHOR-GURU IB/ESS 186
  187. 187. 5/1/2013 AUTHOR-GURU IB/ESS 187
  188. 188. 5.Beating trays for invertebrates in trees 5/1/2013 AUTHOR-GURU IB/ESS 188
  189. 189. 5/1/2013 AUTHOR-GURU IB/ESS 189
  190. 190. 5/1/2013 AUTHOR-GURU IB/ESS 190
  191. 191. • When estimating population size it is important to collect RANDOM SAMPLES. • A sample is a part of a population, part of an area or part of some other whole thing, chosen to illustrate what the whole population, area or other thing is like. • In a random sample every individual in a population has an equal chance of being selected. 5/1/2013 AUTHOR-GURU IB/ESS 191
  192. 192. • Quadrats METHOD 5/1/2013 AUTHOR-GURU IB/ESS 192
  193. 193. 5/1/2013 AUTHOR-GURU IB/ESS 193
  194. 194. 5/1/2013 AUTHOR-GURU IB/ESS 194
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  196. 196. 5/1/2013 AUTHOR-GURU IB/ESS 196
  197. 197. Using Quadrats 1. Mark out area to be sampled. 2. Place quadrates ( 1 m2, 10 m2) randomly within the area. 3. Count how many individuals are inside each of the quadrates. 4. Calculate the mean number of individuals per quadrate. 5. Pop. Size = mean x total area area of each Quadrat 5/1/2013 AUTHOR-GURU IB/ESS 197
  198. 198. SYSTEMATIC QUDRATS RANDOM QUDRATS Quadrat sampling is suitable for plants that do not move around and are easy to find. 5/1/2013 AUTHOR-GURU IB/ESS 198
  199. 199. Quadrat method can be used to determine:  POPULATION DENSITY = number of individuals of each species per area.  PERCENTAGE FREQUENCY = percent of each species found within an area.  PERCENTAGE COVER = percent of plant covering a given area. 5/1/2013 AUTHOR-GURU IB/ESS 199
  200. 200. 5/1/2013 AUTHOR-GURU IB/ESS 200
  201. 201. Capture/Mark/ Release/Recapture Lincoln index 1. Capture as many individuals as possible in the area occupied by the animal population, using netting, trapping or careful searching. 2. Mark each individual, without making them more visible to predators and without harming them. 5/1/2013 AUTHOR-GURU IB/ESS 201
  202. 202. 3. Release all the marked individuals and allow them to settle back into their habitat. 4. Recapture as many individuals as possible and count how many are marked and how many are unmarked. 10 marked 14 unmarked 5/1/2013 AUTHOR-GURU IB/ESS 202
  203. 203. Capture and Marking 5/1/2013 AUTHOR-GURU IB/ESS 203
  204. 204. Assumptions: 1. The population of organisms must be closed, with no immigration or emigration. 2. The time between samples must be very small compared to the life span of the organism being sampled. 3. The marked organisms must mix completely with the rest of the population during the time between the two samples. 4. Organisms are not hurt or disadvantaged by being caught and marked and therefore all organisms have an equal opportunity of being recaptured 5/1/2013 AUTHOR-GURU IB/ESS 204
  205. 205. 5. Calculate the estimated population size by using the Lincoln Index: population size = N1 X N2 N3 N1 = number caught and marked initially N2 = total number caught in 2nd sample N3 = number of marked individuals recaptured Most suitable for animals that move around and are difficult to find. 5/1/2013 AUTHOR-GURU IB/ESS 205
  206. 206. • Next unit is continuing in the another PowerPoint presentation 5/1/2013 AUTHOR-GURU IB/ESS 206
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