Transcript final slideshow

Ecological principles
Systems, Diversity, and Human Interactions
What is Ecology?

Ecology is the study of how organisms
interact with on another and with their
nonliving environment.
◦ Connections in nature
◦ Ecologists focus on understanding interactions
among organisms, a population, a community,
an ecosystem and the biosphere!
 All of which we will examine!!
What are Organisms??

Organisms are any form of life.
◦ One cell to multi-cellular species.
◦ If you look in the mirror you will see 10
trillion cells and about 200 different types of
cells… all having different functions!

How many different species on Earth?
◦ Estimated = 3.6 million to 100 million
◦ So far we know 1.4 million (mostly insects!)
Case Study: Have you thanked the
insects Today?

Read Page 55 then take five minutes to
answer the portfolio question: Journal
Entry #1.
Organisms make up a Population
A population is a group of interacting
individuals of the same species that
occupy a specific area.
 The place or environment where they live
is its habitat.

◦ It may be as large as an ocean or as small as
the intestine in a termite!!

The area over which we can find a species
is called its distribution or its range.
What is a community?

A community, or biological community,
consists of all the populations of the
different species living and interacting
within an area.

It is very complex and contains plants,
animals, and many microorganisms.
What are Ecosystems?
An Ecosystem is a community of different
species that are interacting with one
another but also with their physical
environment of matter and energy
 They can be natural or man made.

◦ Man made would be crop fields, farm ponds,
and reservoirs.
◦ All the Earth’s ecosystems together make up
the biosphere.
Examples of various ecosystems.
Systems within the Biosphere

All of the earth’s ecosystems combined
make up the biosphere. This includes
ecosystems in the air, land and sea – the
Earth’s life support systems.
But what if we change a component
within an Ecosystem:

Each component of an ecosystem is important to the
preservation and the health of the ecosystem.

When you change one factor you may create a domino
affect – massive changes elsewhere.
If the temperature of earth changes it impacts
the development of species. Since they are all
linked this will in turn affect all other species in
the ecosystem.
Humans interactions with an
ecosystem

Natural balance (characterized by the carrying capacity
of a species) shifts when humans interact.

Sustainable practices are humans ways of minimizing
their impact on the ecosystem and maintaining that
natural balance.
Eutrophication

Eutrophication is a syndrome of ecosystem
responses to human activities that fertilize
water bodies with nitrogen (N) and
phosphorus (P), often leading to changes in
animal and plant populations and
degradation of water and habitat quality.

Nitrogen and phosphorus are essential
components of structural proteins,
enzymes, cell membranes, nucleic acids, and
molecules that play a role in photosynthesis
and other cellular functions .

Pristine aquatic ecosystems function in
approximate steady state in which primary
production of new plant biomass is
sustained by N and P released as
byproducts of microbial and animal
metabolism.
◦ Humans disrupt this
balance by adding N
and P to the water
systems.
◦ Nutrient enrichment
of marine waters
promotes the growth
of algae.
◦ The algae fuels
bacterial growth in
bottom waters and
sediments.
Then….

Bacterial metabolism
consumes oxygen.

Bottom waters become
hypoxic (low in oxygen)
or anoxic (devoid of
oxygen), creating
conditions stressful or
even lethal for marine
invertebrates and fish.
Possible Results
Seagrass populations
decrease due to
unavailability of light.
Ecosystem balance is
effected.
 Some phytoplankton
species excrete large
quantities of mucilage
during blooms that is
whipped into foam by
wind mixing and washes
ashore, making beaches
undesirable for holiday
visitors.


Other phytoplankton (cyanobacteria)
species produce toxic chemicals that can
impair respiratory, nervous, digestive and
reproductive system function, and even
cause death of fish, shellfish, seabirds,
mammals, and humans.

The economic impacts of harmful algal
blooms can be severe as tourism is lost and
shellfish harvest and fishing are closed
across increasingly widespread marine
regions.

Rivers and streams damage result in loss of
fish stocks!
Nitrogen Eutrophication…

Portfolio: Bringing Dead Zones back to
Life – article and Questions.
The Earth is made up of Four
Major Layers:
The Earth is made up of interconnected
spherical layers that contain air, water, soil,
minerals and life.
1. Atmosphere (air)

The thin membrane of air around the planet.

The atmosphere is made up of two parts (for our
purpose):
◦ Troposphere: The bottom layer just above sea level. It contains
most of the earth’s nitrogen and oxygen – and is where the
weather occurs.
◦ Stratosphere: This is the upper layer. It contains mostly ozone
(O3), which helps to filter out the sun’s harmful ultraviolet rays.
2. Hydrosphere – water

The hydrosphere consists of the Earth’s
water - it is found as liquid water (surface
and undergound), as ice (polar ice,
icebergs and ice in frozen soil), and as
water vapour.
3. Lithosphere – crust

The lithosphere is made up of the Earth’s
crust and upper mantle.
 It contains non-renewable fossil fuels, minerals and
nutrients for plant growth.
4. Biosphere - (living and dead organisms)

The biosphere is where all living organisms exist and
interact with one another and with non-living things.

The biosphere includes most of the hydrosphere (water),
parts of the atmosphere (air), and lithosphere (soil).
All life exists in the biosphere…
In order for life to exist
organisms need to obtain
nutrients and minerals for
growth and maintenance.
 The Earth is a closed
system; therefore,
everything needs to be
recycled once an organisms
dies… it has to be broken
down and released back
into the ‘web of life’.

The Earths Cycles – Found within
the Biosphere
Carbon cycle
Carbon is the basic building block of the
carbohydrates, fats, proteins, DNA, and other
organic compounds necessary for life.
 The carbon cycle is based on CO2 from the
aerobic respiration of organisms, volcanic
eruptions, the weathering of carbonate rocks, and
the burning of carbon containing compounds.
 Aerobic respiration breaks down glucose and
converts the carbon to the CO2 which is
released into the troposphere.

Nitrogen Cycle
Nitrogen is the atmosphere’s most
abundant element (78%).
 It is a crucial component of proteins,
many vitamins, and the nucleic acids DNA
and RNA.
 However, N2 (gas) cannot be absorbed
and used directly as a nutrient by plants
or animals.
 The nitrogen cycle converts it to a usable
form.

Phosphorus Cycle
Phosphorus is typically found as a solid
form in rocks and salts in the Earth’s crust
and very little circulates the atmosphere.
 As weathering and erosion occur
phosphorus is released into soil water,
lakes, and rivers as phosphate ions that
can be taken up by plants – which are
then eaten by other organisms.

Sulphur Cycle

Sulphur enters the atmosphere through
natural sources and human activity.

It can create many problems for
organisms and water systems as it falls
from the atmosphere as acid
precipitation.
Water Cycle
One of the most important cycles on the
Earth!!
 The water cycle recycles the fixed supply
of the Earth’s water.
 It falls to the Earth in forms of precipitation
and cycles through plants and animals.
 It is different from other cycles as the
chemical (H2O) stays unchanged but
merely transforms from one state to
another.

What are the Major Biological
Components of Ecosystems?

Organisms on our planet either produce
or consume food.
◦ Producers, also known as autotrophs, make
food from the environment
◦ Plants, algae, and phytoplankton are the key
producers in the biosphere.
◦ Producers make glucose (a carbohydrate)
through a process known as photosynthesis.
◦ http://www.youtube.com/watch?v=mYbMPwm
wx88&feature=related
Distribution of Autotrophs
All other organisms… Consumers
Consumers = heterotrophs
 They obtain energy and nutrients from
feeding on other organisms or remains.
 Decomposers are consumers that recycle
organic matter (which we seen in cycles).

◦ Breakdown dead organic material = detritus!

In natural ecosystems there is little to no
waste as one organism’s waste serves as a
resource for another.
Energy passed on…

All producers, consumers, and decomposers
use the chemical energy in glucose to
fuel all their life processes.
◦ The survival of all individuals depends on the flow of
matter and energy through its body.

As an ecosystem, the whole survives
primarily through the recycling of matter
and the one-way energy flow.
 Food chains
 http://www.youtube.com/watch?v=o_RBHfjZsUQ&feat
ure=fvsr
Major Components of a Freshwater
Ecosystems
Major Components of an Ecosystem
in a Field
Decomposers and Detritus Feeders
Energy Flow in Ecosystems

All organisms, essentially, are food for
other organisms within an ecosystem.

Complete the assignment on Food Chains
and Webs + Energy Flow in Ecosystems.
Origins and Biodiversity

Life on Earth developed as a result of
chemical and biological evolution.
•Chemical evolution: The formation of organic
molecules took around one billion years to form.
• Biological
evolution: Followed, from single-celled
prokaryotic bacteria to single-celled eukaryotic
organisms to multi-cellular organisms.
• It still continues 3.7 billion years later.
• We
have knowledge of the evolution
of species from fossils, radioactive
dating, ice-core drilling, chemical
analyses, and DNA analysis –
however, many of these records are
incomplete.
Evolution and Adaptation

Evolution is the change in a population’s
genetic makeup over time.
◦ Populations evolve by becoming genetically different
◦ All species descend from earlier, ancestral species (theory
of evolution – this is only one theory… there are others!)
◦ Microevolution:
◦ Macroevolution:
small genetic changes in a population
long-term, large-scale evolutionary changes.
Genetic Changes

A population’s gene pool
changes over time because
of genetic mutations in
DNA molecules.

These are passed on to
the offspring and then
through their reproduction
more mutations can occur.
Genetic changes can lead to
Biodiversity
Biodiversity is the variation of life forms
within a given ecosystem, biome, or for
the entire Earth.
 Having a high biodiversity helps keep our
economies running and keeps us alive!
 Habitats with higher diversity and
complexity lead to more stable
environments with greater species and
genetic diversity.

Earth’s Biodiversity
The biodiversity of our planet is decreasing
because of human activity.
 Biodiversity = speciation – extinction
 It is estimated that humans have increased
extinction rates by 100 to 1,000 times in the
20th century.
 It is now predicted that by the end of the 21st
century we may see the extinction of over half of
the species now present on Earth.
 Humans and our activities are destroying or
degrading ecosystems that might be centers for
future speciation.

1. Genetic Diversity
Genetic diversity: the variety of genetic
material within a species or a population.
◦ Mutations: changes in the genetic makeup of an organism
◦ Migration: organisms have to adapt to new environments.
◦ Population size: the smaller the population the less
genetic diversity it can contain and the fewer the variations
in the genes for specific characteristics.
◦ Selective Breeding: domesticated plants and animals
have been modified over many generations by humans
choosing certain desired characteristics.
Genetic Diversity in Chilis
2. Species Diversity
Species diversity: the number of species present
in different habitats.
◦ A region impacts its species diversity (ex. temperature in
rainforest promotes diversity).
◦ Migration can introduce new species to an area where
they were not present. This does not always increase
populations if it is an invading species.
◦ The size of the area affects species diversity. The larger the
area the larger the species diversity.
3. Functional Diversity
 Functional
diversity: the biological and
chemical processes such as energy flow and
matter cycling needed for the survival of
species, communities, and ecosystems.
 If
matter is ‘lost’ or removed from an
ecosystem the cycling of nutrients cannot
occur therefore different species will be
affected.
4. Structural Diversity
•
Structural diversity is
the range of variation
in the physical
characteristics of a
habitat
•
An ecosystem that
provides niches for
different organisms to
survive will increase
the diversity within the
ecosystem.
5. Ecological Diversity

Ecological diversity: the variety of
terrestrial and aquatic ecosystems found in an
area.

Each area will differ in terms of their types of
species, water sources, terrain (ex. rocky or
sandy, slopes facing north or south), weather
patterns (ex. hurricanes).
Ecosystem Diversity
Aquatic ecosystems
 Coral reefs
 Tropical rainforest
 Tundra
 Old growth forests
 Marine ecosystems
 Plains

Factors that Lead to Loss of Diversity

When species of plants and animals go extinct,
many other species are affected.

Some examples of factors leading to species
extinction are:
Habitat destruction
Pollution
Species Introductions
Global Climate Change
Exploitation
Logging - Human Impact
The rainforest loses a football field every
second because of logging.
 Humans cut down the rainforest to
create grazing areas for cattle and farming
 After a few years the soil is so depleted
you cannot grow anything on it therefore
cows cannot even graze grass.
 When we cut down the forest we are
removing species we do not even know
exist!

Farming – Human Impact
Kelly’s Cross land
changes.
 Monoculture
farming – disease
spreads quickly,
pesticide resistant
organisms, high use
of fertilizer,
deforestation, etc.

Unregulated Hunting

Fishing generally has the capacity to
damage fragile marine ecosystems and
vulnerable species such as coral reefs,
turtles and seabirds.
◦ In fact, all eight sea turtle species are now
endangered, and illegal fishing and hunting are
two major reasons for their destruction.

Hunting for sport has obliterated
species.
◦ The dodo bird's disappearance is attributed in
part to sport hunters, and the historical
decimation of the American buffalo from sport
hunters nearly pushed that species to total
extinction.
Urbanization – Human Impact

Unlike rural communities, urban sprawl
completely transforms the landscape and
the soil and alters the surrounding
ecosystem and the climate.
◦ While increasing urbanization may have some
positive impacts on our environment, such as
the lower birth rates that come with a city
lifestyle, scientists are becoming more
concerned about the negative long-term
effects.
Pollution
Where to start!!
 Increase in atmospheric concentrations of
greenhouse gases, build up of solid wastes
in ecosystems, increased water
temperatures can decrease breeding and
nesting areas, can poison species (grade
ten science – frogs disappearing!).
 The list goes on and on…

Introduction of New Species

These animals are released into the local ecosystems
and cause damage to fauna and flora, and are
threatening to upset the delicate balances that exist in
the local ecosystems.

Clubbed tunicate, green crab, etc.
Where did they come from?
Shipping - The greatest source of invasive species is ballast water taken
on ships for stability and later dumped into harbours worldwide. Other
plants and animals arrive as stowaways hidden in cargo on ships, trains,
and trucks.
Recreation - Plants and animals often hitch rides on watercraft, mountain
bikes, all-terrain vehicles, hiking boots, and fishing gear.
Gardening and Agriculture - The escape of cultivated plants from
gardens and croplands to wetlands, grasslands, and roadsides is a
common vehicle for alien invaders, such as purple loosestrife and garlic
mustard, which now cover millions of hectares all across Canada.
Natural Pathways - Wind, water, and wildlife can advance the spread of
exotic plants and animals.
Intentional Releases - European starlings and house sparrows let loose
in New York City's Central Park now blanket the western hemisphere.
Brown trout and carp introduced from Eurasia now flourish in North
American waters.
Canal Construction - Artificial waterways have allowed the sea lamprey,
an eel-like fish from the Atlantic Ocean, to cross natural barriers and
invade the Great Lakes.
Extinction

When a population
cannot adapt to
changing
environmental
conditions the species
will become extinct.
◦ Species usually only
last 1-10 million years.
◦ Life has had to cope
with natural disasters
that have eliminated
species.
◦ Introduction of new
species can lead to the
extinction of another.
All species will become extinct…
When local environmental conditions
change, some species will disappear at a
low rate.
 In a mass extinction, there is a significant
rise in extinction rates

◦ Usually 25-70% of species are lost.
◦ There have been two mass extinctions on
Earth.
◦ As well, two mass depletions have also
occurred (not as large as an extinction).
Genetic Engineering

Genetic engineers have
transplanted genes from one
species to another to create
genetically modified
organisms (GMO’S).
◦ Genes from different species that
would never interbreed in nature are
being transferred from one organism
to another.
◦ Gene splicing (as it’s called) takes
half as much time to develop a new
crop or animal, as does traditional
crossbreeding.
Genetic Engineering

Cloning produces a
genetically identical version
of an individual.

Bio-pharming is a new
field where genetically
engineered animals act as
biofactories to produce
drugs, vaccines, antibodies,
hormones, etc.
Where are they today?

Scientists have used gene splicing to
develop modified crop plants, drugs,
pest-resistant plants.
 Created genetically engineered
bacteria to clean up oil spills and
other toxic pollutants.

They have cloned sheep and cows –
in the future they may be able to
clone humans!
 Engineered chickens that lay low
cholesterol eggs, tomatoes with genes
to lower chances of certain cancers,
and bananas and potatoes that treat
various viral diseases in developing
countries.