Download Organization

Ecological Organization
Intro to Enviro Expo Part 1
Key Concepts…
From way back in Biology:
• interactions within and among populations
• nutrient cycling with energy flow through
ecosystems;
• the effects of natural events and human
activities on ecosystems; and
• analysis of the flora, fauna, and
microorganisms of Virginia ecosystems
including the Chesapeake Bay and its
tributaries.
What is ecology?
•The scientific study of
interactions between
organisms and their
environments, focusing on
energy transfer
•It is a science of relationships.
What do you mean by environment?
The environment is made up of two
factors:
Biotic factors- all living organisms
inhabiting the Earth
Abiotic factors- nonliving parts of
the environment (i.e. temperature,
soil, light, moisture, air currents)
Biosphere
Ecosystem
Community
Ecological Organization
Think of it as a
hierarchy, a way of
organizing &
breaking
ecology/environment
down into smaller
sections
Population
Organism
Organism- any unicellular or
multicellular form exhibiting all of the
characteristics of life, an individual.
•The lowest level of organization
Population-a group of organisms of
one species living in the same place
at the same time that interbreed
and compete with each other for
resources (ex. food, mates, shelter)
Community- several interacting
populations that inhabit a common
environment and are interdependent.
Ecosystem- populations in a
community and the abiotic factors
with which they interact (ex.
marine, terrestrial)
Biosphere- life supporting portions
of Earth composed of air, land,
fresh water, and salt water.
•The highest level of organization
YOUR TASK:
Either on your own or with a partner
(and if you work with a partner your
end product better show that 2
people put work into it!), come up
with a way to physically represent
these relationships (community,
population, organism, etc). You may
use common everyday items, that you
carry with you or are located in the
Ecology – Part 2
Relationships
• Spatial
• Feeding
• Symbiotic
“The ecological niche of an
organism depends not only on
where it lives but also on what
it does. By analogy, it may be
said that the habitat is the
organism's „address‟, and the
niche is its „profession‟,
biologically speaking.”
Odum - Fundamentals of Ecology
Spatial Relationships
Habitat vs. Niche
Niche - the role a species plays in
a community (job)
Habitat- the place in which an
organism lives out its life
(address)
Habitat vs. Niche cont…
A niche is determined by the
tolerance limitations of an organism
(limiting factor)
Limiting factor- any biotic or abiotic
factor that restricts the existence of
organisms in a specific environment.
Habitat vs. Niche
Examples of limiting factors•Amount of water
•Amount of food
•Temperature
Feeding Relationships
•
There are 3 main types of feeding
relationships
1. Producer- Consumer
2. Predator- Prey
3. Parasite- Host
Feeding Relationships
Producer– all autotrophs (plants)
– trap energy from the
sun
– bottom of the food
chain
Feeding Relationships
Consumer- all heterotrophs
– they ingest food containing the sun’s
energy
•
•
•
•
Herbivores – eats plants, primary consumers, prey animals
Carnivores – eat meat, predators, hunt prey for food
Omnivores – eat both plants and animals
Decomposers – feed on dead organisms (variety of kinds)
Feeding Relationships
ConsumerHerbivores
• Eat plants
• Primary consumers
• Prey animals
Feeding Relationships
ConsumerCarnivores
• eat meat
• Predators
– Hunt prey
animals for food.
Feeding Relationships
Consumer• Scavengers
– Feed on carrion,
dead animals… which
makes them carnivores
– Can be just about
any kind of animal
Feeding Relationships
ConsumerOmnivores
-eat both plants
and animals
Feeding Relationships
ConsumerDecomposers
– Breakdown complex
compounds into simpler
molecules that can be
absorbed back into the
soil
– Majority are
microscopic and
bacterial in nature
Feeding Relationships
Food chain- simple model that
shows how matter and energy
move through an ecosystem
Feeding Relationships
Food web- shows all possible
feeding relationships in a
community at each trophic level
• Represents a network of
interconnected food chains
Food chain
(just 1 path of energy)
Food web
(all possible energy paths)
Trophic Levels
• Each link in a food chain is known
as a trophic level.
• Trophic levels represent a feeding
step in the transfer of energy
and matter in an ecosystem.
• Can be producers, 1st consumer,
2nd consumer, 3rd consumer (etc.)
Trophic Levels
Biomass- the amount of organic matter
comprising a group of organisms in a
habitat.
• As you move up a food chain, both
available energy and biomass
decrease.
• Energy is transferred upwards but is
diminished with each transfer.
– Only about 10% is transferred
E
N
E
R
G
Y
Trophic Levels
Tertiary
consumers- top
carnivores
Secondary consumerssmall carnivores
Primary consumers- Herbivores
Producers- Autotrophs
Toxins in food chainsWhile energy decreases as it moves up
the food chain, toxins increase in
potency.
•This is called biological magnification
Ex: DDT & Bald Eagles,
Mercury in fish
(shark, king
mackerel, swordfish and tilefish are
high in mercury)
Symbiotic Relationships
Symbiosis- two species living together
3 Types of
symbiosis:
1. Commensalism
2. Parasitism
3. Mutualism
Symbiotic Relationships
1. Commensalismone species benefits
and the other is
neither harmed nor
helped
Ex. orchids on a tree
Epiphytes: A plant, such as a
tropical orchid or a bromeliad,
that grows on another plant
upon which it depends for
mechanical support but not for
nutrients. Also called
aerophyte, air plant.
Symbiotic Relationships
2. Parasitismone species benefits (parasite) and
the other is harmed (host)
• Parasite-Host relationship
Example: tick on a deer, leeches, fleas,tapeworm
Symbiotic Relationships
3. Mutualismbeneficial to
both species
Ex. cleaning birds
and cleaner
shrimp
Symbiotic Relationships
3. Mutualism (cont.)
beneficial to both species
Ex. lichen
Type of
Species
relationship
harmed
Commensalism
Parasitism
Mutualism
= 1 species
Species
benefits
Species
neutral
Biogeochemical Cycles
Intro to Enviro Expo Part 3
Nutrient Cycles
Cycling maintains homeostasis
(balance) in the environment.
•3 cycles to investigate:
1. Water cycle
2. Carbon cycle
3. Nitrogen cycle
Water cycle•Evaporation, transpiration,
condensation, precipitation,
condensation, infiltration/percolation,
runoff
Water cycle-
Carbon cycle•Photosynthesis and respiration
cycle carbon and oxygen through
the environment.
Carbon/Oxygen Cycle
~ Photosynthesis and respiration cycle
carbon and oxygen through the environment.
O2
CO2
Carbon cycle-
Carbon Cycle
• In fact, carbon constitutes the very
definition of life
– Its presence or absence helps define whether a
molecule is considered to be organic or
inorganic.
• Every organism on Earth needs carbon
either for structure, energy, or, as in the case
of humans, for both.
Carbon Cycle
• Carbon is found in forms as diverse as:
– GAS
• carbon dioxide (CO2)
– SOLIDS
•
•
•
•
•
•
limestone (CaCO3)
Wood
Plastic
Diamonds
Plants
Graphite
Carbon Cycle
• ON LAND - the major exchange of carbon with
the atmosphere results from:
– Photosynthesis and
– respiration
Carbon Cycle
ON LAND - the major exchange of carbon with the
atmosphere results from
– During daytime in the growing season, leaves absorb
sunlight and take up carbon dioxide from the
atmosphere (photosynthesis).
– At the same time plants, animals, and soil microbes
consume the carbon in organic matter and return carbon
dioxide to the atmosphere (respiration).
Carbon Cycle
So can the amount of carbon in the
atmosphere change?
Yes!
During winter for instance, there are hardly any leaves
on the trees, so photosynthesis decreases, thus the amount of
CO2 being taken in by these leaves is decreased.
BUT…
At the same time animals are still respiring/exhaling the same
amount of CO2 that they were in all the other seasons
SO…
The amount of CO2 in the atmosphere during winter has
_____________________.
increased
Carbon Cycle
So can the amount of carbon in the
atmosphere change?
http://www.bbc.co.uk/cumbria/content/images/2007/02/06/winter_trees_
470x353.jpg
http://www.craiglauder.com/gallery/Limberlost/images/SUmmer_Trees_Lake.jpg
So an increase in CO2 in atmosphere during winter
in our Northern Hemisphere
Nitrogen cycleAll organisms need N to build proteins
(which are used to build new cells).
Atmospheric nitrogen (N2) makes up nearly
78%-80% of air.
Organisms can not use it in that form.
Lightning and bacteria convert nitrogen into
usable forms.
Nitrogen cycleOnly certain bacteria and industrial
technologies can fix nitrogen.
Nitrogen fixation-convert atmospheric
nitrogen (N2) into ammonium (NH4+)
which can be used to make organic
compounds like amino acids.
N2
NH4+
Nitrogen cycleNitrogen-fixing
bacteria:
Some live in a
symbiotic
relationship with
plants of the legume
family (e.g.,
soybeans, clover,
peanuts).
Nitrogen cyclehttp://www.tokyomango.com/tokyo_mango/images/2007/10/0
5/super_mushroom.jpg
• Decomposers help by breaking up stored
Nitrogen (in wastes, leaves, decaying
plants/animals) and putting Nitrogen back
into the soil
– Then bacteria in the soil turn a small
portion into Nitrogen gas and returns
it to the atmosphere – so that
completes the cycle.
Nitrogen cycle•Some nitrogen-fixing bacteria live free in the
soil.
•Nitrogen-fixing cyanobacteria are essential to
maintaining the fertility of semi-aquatic
environments like rice paddies.
Unicellular nitrogen-fixing
cyanobacteria, shown in this
light micrograph, play an
important role in the oceanic
nitrogen cycle. (Credit: Washington
University in St. Louis)
Lightning
Atmospheric
nitrogen
Nitrogen Cycle
Denitrification
by bacteria
Animals
Nitrogen
fixing bacteria
Decomposers
Ammonium
Nitrification
by bacteria
Plants
Nitrites
Nitrates
Phosphorus cycle• Essential to form bones and teeth in animals,
also helps increase growth in plants
• Phosphorus cycle moves from the
environment to organisms, then back to
environment again. (so doesn’t really cycle through
the atmosphere)
http://www.gonzaga.edu/campus+resources/sustainability/Images/waterfall_
web_environment.jpg
Phosphorus cycle• Enters soil when rocks erode or when
decomposers break down the remains of
dead plants and animals
• Plants then absorb phosphorus through their
roots and the cycle is complete.
How do Humans Affect the Nitrogen and
Phosphorus Cycles?
• Humans have increased the natural rate of
nitrogen and phosphorus, through the use of
chemical fertilizers.
- When excess nitrogen and phosphorus compounds
run off fields into bodies of water, they can cause an
overgrowth of algae blooms and aquatic plants.
- If abundance of aquatic plants, then
abundance of plant decay and abundance of decomposer, which
deplete oxygen that other aquatic organisms need to survive.
Algal Blooms
http://serc.carleton.edu/images/microbelife/topics/red_tide_genera.v3.jpg
http://media.supereco.com/media/2009/02/02/320w/algae-bloom.jpg
http://www.waterencyclopedia.com/images/wsci_01_img0017.jpg