Download Ecosystem

Ecology:
• the study of the interactions of living things
with each other and their physical
environment
Organisms
• An organism is a living thing that has
needs to survive. It belongs to one of the
following kingdoms:
• Animalia
• Plantae
• Fungi
• Protista
• Monera (Archaebacteria and Eubacteria)
Ecosystem
• An ecosystem is all the organisms that live
in an area together with the nonliving
factors of the environment.
• The example is a pond ecosystem.
An ecosystem is self-sustaining if the
following requirements are met:
1. A constant source of energy and a
living system capable of incorporating
this energy into organic molecules
(molecules in living things).
2. A cycling of materials between
organisms and their environment.
Environments
• These are the surroundings and the
conditions under which an organism lives.
Interactions
• This includes how the populations of organisms interact with each
other in a given area (biotic factors).
• This also includes how organisms affect and interacts with the nonliving (abiotic factors) around them.
Biotic factors:
• all the living things that directly or indirectly
affect the environment
• ** Thus, the organisms, their presence,
parts, interaction, and wastes are all biotic
factors.
Abiotic factors:
• those physical and chemical factors in the
environment which affect the ability of
organisms to survive and reproduce.
Some Abiotic Factors:
1. intensity of light
2. range of temperatures
3. amount of moisture
4. type of soil or rock type
5. availability of substances such as
minerals
6. supply of gases such as oxygen, carbon
dioxide, and nitrogen
7. pH
Energy Flow
• If an ecosystem is to be self-sustaining it
must contain a flow of energy.
• Those life activities that are characteristic
of living organisms require an expenditure
of energy.
• The pathways of energy through the living
components of an ecosystem are
represented by food chains and food webs.
• Producers convert the radiant energy of the
sun into the chemical energy of food.
Nutritional Relationships:
A.
Producers: can make their own food from the energy of the sun,
water, and CO2 from the air. Carry out the process of
photosynthesis.
B.
Consumers: can NOT make their own food and are dependent on
other organisms for their food.
Carry out the process of
respiration.
Decomposers: Cannot make their own food. They are also
dependent on other organisms. They break down dead organisms
or waste materials from dead organisms for their nutrietns.
B.
What happens during
photosynthesis?
• Plants capture light energy and use that energy to make glucose
• Sunlight provides the energy needed by chlorophyll to change
molecules of carbon dioxide and water into glucose
• Oxygen is also released in this reaction
What happens during
respiration?
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Glucose molecules break down to release energy
This process requires oxygen
This process produces water and carbon dioxide as waste products
Occurs in the mitochondria
Most organisms carry on cellular respiration
A.
Food chain: involves the transfer of energy from green
plants through a series of organisms with repeated
stages of eating and being eaten
B.
Food web: In a natural community, the flow of energy and
materials is much more complicated than illustrated by
any one food chain.
Food Chains
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A food chain traces the path of energy as it moves from one organism to the
next in an ecosystem.
Energy begins with the sun so producers make their own food.
The primary consumer is the first to feed.
The secondary consumer feeds on the primary consumer.
The tertiary consumer feeds on the secondary consumer.
Food Web
Food Webs
• Most organisms are part of more than one
food chain.
• A food web is a system of several
overlapping food chains.
Energy Flow:
• Energy flows through ecosystems in one direction,
typically from the Sun, through photosynthetic
organisms, including green plants and algae, through
herbivores, to carnivores, and finally decomposers.
Food Web Interactions:
1. Producers: (plants) -- the energy of the
community is derived from the organic
compounds in plants
- (grass in the web above)
2. Primary Consumer: (always a herbivore)
- feeds on plants (mice, grasshoppers,
and rabbits in the web above)
3. Secondary Consumer: (usually a carnivore)
-- feeds upon other consumers (frogs,
sparrows, snakes, and foxes above)
(The hawk is a secondary or 3rd level
consumer depending on the availability of
food.)
Omnivores may be primary or secondary
consumers.
Tertiary Consumers
• Tertiary Consumer: (Always a carnivore)
--feeds on other consumers that feed on a
consumer that fed on a previous consumer.
These creature are at the top of their food
chain!!
4. Decomposers: break down organic wastes
and dead organisms to simpler substances
(ex. bacteria of decay)
** Through decomposition, chemical
substances are returned to the
environment where they can be used by
other living organisms.
Autotrophs/Heterotrophs
• Autotrophs make their own food
(producers).
• Heterotrophs must obtain their food,
(consumers).
Types of Heterotrophs:
Saprophytes: include those heterotrophic
plants, fungi, and bacteria which live on
dead matter - AKA decomposers
Herbivores: plant-eating animals
Carnivores: meat-eating animals
Omnivores: consume both plants and meat
Types of Carnivores:
• Predators: animals
which kill and consume
their prey
• Scavengers: those
animals that feed on
other animals that they
have not killed
Energy Transfer:
• Each consumer level of the food pyramid
utilizes approximately 10% of its ingested
nutrients to build new tissue.
• This new tissue represents food for the
next feeding level.
Yummy
!
Energy Pyramids
• The decrease in available energy at each
level of a food chain is shown in an energy
pyramid.
Biomass:
• amount of organic matter
• The decrease of energy at each successive feeding level
(trophic level) means that less biomass can be supported at
each level.
• Thus, the total mass of carnivores in a particular ecosystem
is less than the total mass of the producers. (A pyramid of
biomass illustrates this.)
• There is a decrease in the overall energy in each level
as you move up the food web.
• This means that there is much more energy in the
producer level in a food web than at the consumer
levels.
• Also, this means that there is more energy at the primary
consumer level than at the secondary consumer level.
• The remaining energy is lost in the form of heat and
unavailable chemical energy. Eventually, the energy in an
ecosystem is lost and is radiated from the earth.
• Thus, an ecosystem can not survive without the constant
input of energy from the sun.
Ecological Organization:
1.
2.
3.
4.
5.
6.
7.
Organism: A living thing (individual such as a plant or animal).
Species: Similar organisms that can reproduce fertile offspring.
Population: all the members of a species inhabiting a given location
Community: all the interacting populations in a given area
Ecosystem: the living community and the physical environment
functioning together as an independent and relatively stable system.
Biome: Geographic area on Earth that contains ecosystems with similar
biotic-abiotic features and climate characteristics.
Biosphere: The part of Earth able to support life.
Factors that affect Populations
• For any population to thrive, there must be enough food,
water and living space. Such factors are limiting factors
because they limit how many organisms can live in an
environment.
Relationships between
Populations
• Different species, or kinds, or
organisms living together interact
with one another. The
relationships can be divided into
three main categories:
– Competition
– Predation
– Symbiosis
Competition
• In all
environments,
organisms with
similar needs
may compete
with each other
for resources,
including food,
space, water,
air, and shelter.
• ** The more similar the requirements of
the organisms involved, the more intense
the competition.
Competitive Exclusion Principle
• If two different species compete for the
same food source or reproductive sites,
one species may be eliminated.
Predation
• This is the feeding relationship in which one
animal captures and eats another animal for
food.
• The animal that is eaten is the prey.
• The animal eating the prey is the predator.
Symbiotic Relationships:
• Symbiosis: a close relationship between
two species.
• Types of (symbiosis):
MUTUALISM
PARASITISM
COMMENSALISM
2. Mutualism: both organisms benefit from the
association
Clownfish & Anemone:
Nile crocodile & plover bird
The tentacles provide a clownfish The crocodile will open
protection from predators. The
its mouth when it needs a
clownfish lure fish towards the
teeth cleaning. The plover
Anemone so that it can feed.
feeds on the food provided
•
by the crocodile.
3. Parasitism: the parasite benefits at the
expense of the host
ex. athlete's foot fungus on humans,
tapeworm and heartworm in dogs
1. Commensalism: one organism is benefited
and the other is unharmed
ex. barnacles on whales, orchids on
tropical trees
Carrying Capacity
• the maximum number of organisms the
resources of an area can support
• The carrying capacity of the environment is
limited by the available abiotic and biotic
resources, as well as the ability of ecosystems
to recycle the residue of dead organisms
through the activities of bacteria and fungi.
• Niche (Job): the
organism's role in the
community, particularly its
role in relation to food with
other species.
• Habitat - a place where a
plant or animal can get
the food, water, shelter
and space it needs to live.
• Woodpeckers make holes in this cactus to live.
• When the woodpeckers are finished with this housing,
the elf owl and the screech owl move in.
• The elf owl eats insects and the screech owl occupies
the same habitat, but have different niches.
• The environment may be altered in substantial ways
through the activities of organisms, including humans, or
when the climate changes.
• Although these alterations are sometimes abrupt (ex.
Natural disasters), in most cases species replace others,
resulting in long-term gradual changes in ecosystems.
Positive Human Influence
• Humans have changed the capacity of an
environment to support specific life forms.
• People have created wetlands and nesting
boxes.
Negative Human Influence
• Protect the wonderful world around you!
• Remember each habitat is a unique place where plants and
animals make their home.
• We share this Planet with them…….it is not only ours!
• We hold the future of this beautiful Planet in our hands. Our
future and our children’s and their children’s future depends
on the environmental choices we make today…..MAKE THE
RIGHT ONES!!!!!!