Habitats and Environment
Chapter 9
WEEK 8: Habitats and
Environment
LEARNING OUTCOMES
By the end of this week, you should:
have developed a knowledge and understanding of
habitats and environments that exist in them,
be able to identify major factors that produce the
environments of various habitats and distinguish between
biotic and abiotic factors,
have explored technologies used to record environmental
factors and track distribution of species within their
habitats.
Key Terms
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Habitat
Microhabitat
Range
Community
Niche
Biotic factors
Abiotic factors
Qualitative
Quantitative
Micro-environment
Tolerance range
Limiting factor
Complete the
card sort of
key terms
Now use your textbook to
find and describe some
examples for each of the
definitions to fill out your
knowledge!
Habitat:
The location or place where an organism lives at any given
time is known as its habitat.
 Many habitats can be described in general terms as
being
 Terrestrial (e.g. deserts, grasslands, forests etc)
 Aquatic, which includes freshwater, marine and estuarine.
 Members of one species do not live in isolation in a
habitat.
 For example: Ragged-Finned Lionfish – tropical waters
around coral reefs in the
Great Barrier Reef.
Microhabitats
A microhabitat is a more localised or specialised part
of a general habitat.
 For example, in a freshwater pond, some organisms
may occupy the soft sediment at the bottom, while
others may live
among the
aquatic plants.
These are two
different of
many
microhabitats
Niche
 NICHE refers to the ‘way of life of a species’
OR the role of a species in a community
OR the status or role of an organism in its habitat
 A niche can be explained using the example of a human
population within a city.
- groups of people are identified by their way of life, e.g.
educator, surgeon, security guard, etc
- each group can then be subdivided, e.g. the educator role
includes: pre-school teachers, biology teachers, etc
 A niche can be identified in terms of the degree of use of
resources e.g. where it lives, what it eats, when it feeds
Environmental Factors
 The various factors that produce the particular
conditions in a habitat are called environmental
factors.
 BIOTIC or living factors relate to other living
organisms in the environment and include factors
such as the presence of predators, parasites and
competition between members of one species.
 ABIOTIC are non living factors relating to aspects
of soil, water, light, shelter, temperature etc.
Biotic & Abiotic Factors Affecting A Crocodile
Relative humidity
Solar
radiation
Atmospheric gases
Day length
Air
temperature
Parasites
Humans
Prey
Competitors
Salinity
Soil and
water
chemistry
Environmental factors in water
Micro-environments
 Conditions in a small region of habitat
 Many of these can be found within an environment
For example
In Arctic winter
air temp above
snow-covered
may be colder
than the temp
within the snow
layer...
forming different
micro-environments
Range
 The geographic area that encloses all the
habitats where the species lives denotes the
range or distribution map of the species.
Present range of
the Numbat
(Myrmecobius
fasciatus). Their
range is shrinking
because of
feral predators.
Tolerance Range
 Conditions in which an organism can survive.
Beyond these conditions are detrimental.
 The tolerance range of organism affects an
organisms distribution.
Tolerance Range
Limiting Factors
 A requirement that is in short supply can
affect the organisms survival and reproduction
of an organism.
 E.g. Light, water, oxygen, carbon dioxide
Describing environmental
conditions
 An environment can be described in qualitative
terms, such as ‘warm and humid’ where ‘warm’
refers to the air temperature and ‘humid’ refers
to the water vapour content of the air.
 An environment may also be described in
quantitative terms where a numeric value is
stated, such as, ‘the air temperature is 23°c’.
 When scientists measure environmental factors in
a habitat, they usually express their findings in
quantitative term. Some of the devices are shown
on the next slide.
Monitoring Physical Factors
Photo: Courtesy PASCO scientific
Devices for measuring the
physical factors in the field
include the following meters:
 Quantum light meter
 Dissolved oxygen
 Oxygen meter
 pH meter
 Total dissolved solids (TDS) meter
 Current meter
 Multi-purpose meter
 Hygrometer
 Wind meter
 Other equipment includes:
 Secchi discs
 Nansen bottles
Pasco datalogger with
attached sensor
Testing Water
 Why is water important?
 Why test water?
 Research the following water qualities and why
we need to test them:
 Turbidity
 Sulfates
 Nitrates
 Temperature
 pH
FOR THE NEXT SLIDES:
What is the habitat? Microhabitat?
Community? Niches? Biotic factors?
Abiotic Factors? Limiting factors?
Ecosystems
 An ecosystem consists of a community, its
physical surroundings and the interactions
within and between them.
 The living community in every ecosystem
differs in their physical, biochemical and
behavioural adaptations.
Components of an Ecosystem
A biome is a large
geographical
region comprising
natural units
called
ecosystems.
An ecosystem
encompasses the
physical
environment and
the community.
Physical
environment
Community
Ecosystem
Abiotic factors
Biotic
factors
competitors,
symbionts,
predators,
parasites,
pathogens
Physical
environment
Community
atmosphere,
soil,
water,
wind speed wind
direction,
current velocity
Ecosystems
Light intensity varies
Fast flowing water habitat
Still water habitat
There are many
different sorts of
ecosystems from
natural to
artificial, and
they range in size
from large to
small.
Rock habitat
Flow rate varies
Stream bank habitat
Rainfall level varies
Australian Ecosystems 1
Shrublands are
widespread over much
of inland Australia, in
arid and semi-arid
regions.
There are several different types
including mulga, mallee, and
bridalow, each with different
dominating species.
Mulga scrubland
Heathlands are found in
highland areas where
the increase in altitude
creates conditions that
lowland species find
difficult to tolerate.
Heathland, Tasmania
Australian Ecosystems 2
Deserts are rich
and varied in
Australia. They
are generally
defined as having
an annual rainfall
of less than 250
mm in the south
and less than 500
mm in the north.
The desert regions range
from large areas of active
dunes to eroded outcrops,
such as Uluru.
Australian Ecosystems 3
Sclerophyll forests (top,
right) in regions of
higher rainfall on the
east coast of Australia
possess a single canopy
layer of eucalyptus trees
with a lush undergrowth.
Rainforests (bottom,
right) are found in warm
regions of high rainfall.
With fewer eucalypts,
the trees form a dense
canopy with several
understorey layers.
Australian Ecosystems 4
Rock platforms occur on
exposed coasts where wave
action erodes the rock
strata.
Coral reefs are found in the
warm waters of the northern
Australian coastline. The
Great Barrier Reef extends
2000 km along Queensland’s
coast and encompasses many
individual reefs and islands.
The reefs, composed of hard corals,
provide an immensely diverse range of
habitats for many other kinds of marine
organism.
Groupings
Find definitions and examples for the following:
 Autotroph
 Producer
 Heterotroph
 Consumer
 Herbivore
 Carnivore
 Omnivore
 Detritivore
 Decomposer
Producer?
Consumer?
Detritivore?
Producer?
Consumer?
Detritivore?
Producer?
Consumer?
Detritivore?
True or false?
A producer organism in an ecosystem must be
a flowering plant.
2. Different ecosystems have different
communities.
3. Ecosystems can function without producer
organisms.
4. Decomposer organisms are important in
breaking down organic matter to its more
simple constituents.
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Interactions within
Ecosystems
Fill in the table for
interactions within
ecosystems using
your textbook and
the Internet.
Videos
 Symbiosis
 Predator-prey: Lions Vs Elephant
 Predator-prey: Chimpanzee Hunting Monkeys
 Parasitoid
 Human Parasites: Scishow (9 mins)
Habitat
Qualitative
Population
Autotroph
Competition
Parasitism
Abiotic
Community
Heterotroph
Predatorprey
Decomposer
Commensalism
Ecosystem
Mutualism
Quantitative
Detritivore
Biotic
Niche