Transcript Ecology - Humble ISD

Ecology
Chapter 3: The Biosphere
What Is Ecology?

Ecology- is the study of the interactions among
organisms and between the organisms and the
environments in which they live.
(eco means “house”)
.

Biotic factors – all living things
 Ex. Types of plants, animals, bacteria, fungi,
etc.

Abiotic factors – all non-living things
 Ex. Climate, temperature, amount of rainfall,
humidity, light, wind, soil type, nutrients
available, etc.
Ecological Levels of Organization
Smallest
Largest
Individual  Population  Community  Ecosystem  Biome  Biosphere
Go to
Section:
Levels of Organization
Summary





Species-or individual
Population- all of one species
Communities-all populations
Ecosystems- all populations + environment
Biome- large stable ecosystems
 Biosphere- Part
of Earth where life
exists (all biomes)
Species / Individual
 A group of similar looking organisms that
can breed with one another to produce
fertile offspring.
Populations
 Groups of individuals within the same
species that live in the same area
(habitat).
Communities
 All Populations of various species that
live together in a defined area.
Ecosystems
 all members of a
community & the
physical environment
they live in
 What abiotic factors are present?
 What biotic factors are present?
• Habitat: place where an organism lives
Biome
 large, stable groups of ecosystems that
share the same biotic and abiotic factors
Highlighted
Regions
Tropical
Rainforest
Biosphere
 The part of Earth where life exists.
What term is used to refer to each of the
following?
_________________1.
Lake Houston (location)
Habitat
_________________2.
Mississippi river and all of
Ecosystem
the forms of life that are
sustained by it
Population/species
_________________3.
A flock of ducks
Biome
_________________4.
The Sahara desert
Biosphere
_________________5.
All livable areas on Earth
Community
_________________6.
All the deer, ducks, shore
birds, fish and rabbits in an
area
Practice:
Species /
Individual
Population
Community
Ecosystem
 The flow of energy through an ecosystem
begins with the SUN, and is passed on through
various organisms
Sunlight  Producers  Consumers  Decomposers
Sunlight  Producers  Consumers  Decomposers
Producers:
Producers autotrophic organisms
that are able to make own food
from a inorganic substances.
Ex. Plants, algae (phytoplanktonmicroscopic marine plant life)
Consumers:
Sunlight  Producers  Consumers  Decomposers
Consumers: heterotrophic
organisms that get energy by
eating producers and other
consumers. (ex. Deer, hawk,
bear)
Consumers:
Sunlight  Producers  Consumers  Decomposers
Herbivores: eat producers (plants)
ex. Deer, grasshopper, cow
Carnivores: eat other consumers (meat)
ex. Frog, wolf, hawk
Omnivores: eat producers and consumers
ex. Grizzly bear, humans
Detritovore: organic wastes and dead bodies of
plants and animals…. ex. mites, `
earthworms, snails, crabs, vultures
Consumers:
Sunlight  Producers  Consumers  Decomposers
Level of Consumers:
Primary consumer Secondary consumer3rd, 4th …level consumer
Herbivore
Carnivore
________________
__________________
Omnivore & decomposers
_______________________ can be 1st,2nd or higher level consumer
Sunlight  Producers  Consumers  Decomposers
Decomposers:
 Obtain energy from eating the remains of other
organisms (recyclers) Ex.
•Two Principle Decomposers:
Bacteria and Fungi
Worms
Bacteria
Fungi
Termites
Earthworms and termites (detritivores) also aid in the breakdown
of organic matter, which replenishes nutrients to the soil.
Feeding Relationships
Decomposers
1st
2nd
3rd
4th
5th
Each step in the food chain or web is called a
trophic level, or a feeding relationship between
organisms.
What is always found at the second trophic level?
Food Chains
 Food Chain a series of steps in which
organisms transfer energy by eating and
being eaten.
Energy
flows to
Energy
flows to
Energy
flows to
The arrows show the flow of energy and matter as one
organism is eaten by another.
Trophic Levels
5th
4th
4th consumers
Top Carnivores
3rd consumers
Carnivores
3rd
Secondary consumers
Carnivores
2nd
Primary consumers
Herbivores
1st
Producers
Food Webs
 Food Web: links all the food
chains in an ecosystem
together.
 Any change in a population or
trophic level of a food chain
can seriously alter all other
organisms of the food web!
 A healthy ecosystem has a
large diversity of life because
of the availability of alternative
food sources.
When studying the
overall health of an
ecosystem, we study
food webs.
1. What would happen to this food web is the plants
All populations would die out
were removed? ___________________________
2. Which organism is most vulnerable to changes in
The frog has only one food source
populations?______________________________
3. What happens to the owl population if the foxes we
killed off by humans?________________________
The owl pop. would increase
We can show what goes on with the
help of a Food Web
What would happen if a disease killed off
many of the hawks?
There will be
nothing to eat
the snakes, so
their numbers
will increase.
All the frogs get
eaten
No frogs.
More
crickets
Most of the
cattail gets
eaten by the
crickets
Now the crickets
don’t have enough
food so their
numbers go down
..and so on. Numbers of each species
have an effect on the numbers of the
other species in the web.
ECOLOGICAL
PYRAMIDS
 Ecological Pyramids: show relative
amounts of energy or matter
contained within each trophic
level in a food chain or food web.
Energy Pyramid:
Kcal= kilocalorie
A pyramid of energy illustrate the loss of usable energy at
each feeding level.
Of all the energy consumed by one level, 90% of the
energy is used in the individual’s metabolism. (and lost as
heat)
Only about 10% of the energy available within
one trophic level is transferred to organisms at
the next trophic level. (locked in body tissues)
1 Kcal: Humans
10 Kcal: tuna
100 Kcal: zooplankton
1000 Kcal: plankton
Why do most food chains have no more than 4 or 5
trophic levels? There is very little energy transferred
to support higher trophic levels
Pyramid of Numbers
 show how many individuals are required to
support the next level of feeding.
Why must there be so many more individuals
at lower trophic levels?
Higher trophic levels have to eat more to get the
same amount of energy due to the 10% rule.
Water and Nutrient Cycles
 Energy cannot be recycled or used again.
 However, nutrients/elements in an ecosystem
can be recycled.
 When an animal dies, its matter does not
disappear; rather, it decomposes and gets
used by another organism (through
biogeochemical cycles).
 This occurs through the water cycle, carbon
cycle, nitrogen cycle, and phosphorous cycle.
The Water Cycle
1. According to the diagram, where
does evaporation take place
from?
From Lakes and oceans
2. When water evaporates from the
surface of the Earth, what
process creates clouds?
Condensation
3. Water falls to the earth in a
process called
precipitation.
What are the 4 types of
precipitation?
Rain, snow, sleet, hail
The Water Cycle
4. Plants return excess water to the
atmosphere by evaporating water from its
leaves in a process called:
Transpiration
5. Animals return water by
urination, perspiration, and respiration.
6. Other than plant and animal usage, what are
other destinations for the precipitation that
falls to the Earth?
It can become surface runoff or
groundwater
7. What will ultimately happen to the ground
water and surface water runoff?
It flows back to lakes and rivers to be
evaporated again.
The Carbon Cycle
1. Name and discuss the
process that removes
carbon dioxide from the
atmosphere?
In photosynthesis,
producers remove CO2
gas from the
atmosphere to make
organic molecules
(sugars).
The Carbon Cycle
2. Name and discuss the
processes in which carbon
dioxide is returned to the
atmosphere?
Cellular respiration Animals
burn the food they eat
releasing CO2 gas as a
waste product.
Combustion: Burning Fossil
Fuels. When they are
burned, CO2 gas is returned
to the atmosphere and
increases the amount of CO2
gas in the air.
The Carbon Cycle
3. How is carbon dioxide related to the green house
affect?
Carbon dioxide, methane, and other gases trap heat
energy and maintain Earth’s Temperature range.
The Carbon Cycle
4. It is thought that global warming is caused by
adding carbon dioxide to the atmosphere.
What activities (by human or natural causes) are
thought to speed up global warming?
Burning fossil, cutting down forest, and polluting
oceans (most photosynthesis occurs in oceans)
The Nitrogen Cycle
•Air is 78% nitrogen
•Nitrogen is one of the
elements found in plant
fertilizers
•Protein contains nitrogen
1. Bacteria living in the roots of
the plant help the plant by
convert nitrogen gas to
ammonia
2. Bacteria living in the soil help
plants by
converting ammonia and
nitrogen gas into nitrates and
nitrites.
3. What process transforms
nitrogen into usable forms
that plants can use?
Nitrogen fixation
4. What do plants use these
nitrates and nitrites to make?
Proteins
The Nitrogen Cycle
•Air is 78% nitrogen
•Nitrogen is one of the
elements found in plant
fertilizers
•Protein contains nitrogen
5. Where do animals ultimately get
their proteins from?
Plants
6. How has farming affected the
nitrogen cycle?
Fertilizers add nitrogen
compounds to soil for plants to
use.
7. How has industry affected the
nitrogen cycle?
Burning fossil fuels release
nitrogen compounds that fall to
the earth as acid rain.