Principles of Ecology
What is Ecology?

Ecology is the study of organisms and their environment.

People have always shown an interest in nature and the
environment around them…even you!
 Do
you have a pet?
 Have
 Did

you ever played outside?
you ever have a weather station?
 Have
you ever collected shells or leaves?
 Have
you ever watched shark week?
Ecology combines the study of biology with geology,
chemistry, physics, math, and anthropology.
The Biosphere
 The
Biosphere is the part of the earth that
supports and contains living things.
 This
includes the atmosphere, land, and
water of earth. Although this may seem like a
large space in comparison to the whole of
earth it is but a small part.
Living and Nonliving Things
 Anything
alive is considered to be biotic.
A
biotic factor is any organism that affects a
particular environment.
 Anything
not alive is considered to be abiotic.
 An
abiotic factor is a nonliving thing that is part of the
environment.
 Air,
 They
temperature, rocks, dirt, water, heat, etc.
are both essential parts of the
environment.
Levels of Organization in the Biosphere
Organism
Species
Population
Community
Ecosystem
Biome
Biosphere
Organism
An
individual living thing. It is
Made
up of cells.
Uses Energy
Reproduces
Responds
Grows
Develops
Species
A
group of individuals that can
interbreed and reproduce.
Population
 A group of organisms of the same species
who live in the same geographical area
together and interbreed.
Community
Several
populations of different
species that live in the same
geographical area together.
Ecosystem
A
community of plants and animals
that interact with each other in a
given geographic area and the
abiotic parts of that area.
Biome
A
large group of ecosystems that share
the same type of climax community.
 A climax community is what you
typically see in an area.
In
a rainforest:
In
a coral reef:
On
the South Pole:
Biosphere
The
Biosphere is the portion of the
earth that supports life.
Ecosystems

An ecosystem is made up of interacting populations
in a community and that community’s abiotic
factors.

There are some ideas and terms that we must know
to understand an ecosystem:
1. Habitat-where an organism lives its’ life
2. Niche-a particular role that is filled by an organism
 Only
a certain number of organisms can occupy one niche
at a time.
 An
organism must use certain adaptations and strategies
to stay in its’ niche.
 Think
of our school…
Relationships Between Organisms
Predation
Symbiotic
Relationships
Mutualism
Commensalism
Parasitism
Predation
When
one organism hunts and
consumes another for food.
Mutualism
Both
organisms benefit from
helping each other.
A
bird eating food out of a crocodile’s
mouth.
A clownfish and a sea anemone
Commensalism
One
organism benefits and the other is
not affected.
Think
of a remora hanging out by a shark.
Think of a dung beetle.
Parasitism
One
organisms benefits and the
other is harmed.
Think
of a tick or a leech.
Think of a tapeworm.
Obtaining Energy

Organisms can be either autotrophs or heterotrophs.

Autotrophs collect their energy from the sun or heat.

Heterotrophs collect their energy from other
organisms (by eating them).

 Carnivores
eat only meat
 Herbivores
eat only plants
 Omnivores
eat both
Decomposers get their energy from breaking down
dead organisms which also releases their nutrients
back into the environment.
Food Chains and Food Webs
A
food chain describes the flow of energy in a series
of organisms
 A food web contains many interconnected food
chains.
 A trophic level represents a feeding step in a food
chain or food web.
Only
10% of the energy is passed from one trophic level
to the next.
Fewer
organisms make up each successive level.
Trophic Levels
 Trophic
levels consist of:
Producers
Primary
Consumers
Secondary
Tertiary
Consumers
Consumers
(Sometimes)
Quaternary Consumers
Some organisms can fall into more than one
category.
Food Chain Activity
Energy Pyramid
A
model that represents all of the
energy in an ecosystem.
 Biomass is the total weight of all
matter at each level or in the whole
pyramid.
Cycles in Nature
The
Water Cycle
The Carbon Cycle
The Nitrogen Cycle
The Phosphorus Cycle

https://www.youtube.com/watch?v=al-do-HGuIk

https://www.youtube.com/watch?v=Q0-Vj4CQrJ8

https://www.youtube.com/watch?v=ShP5SUuTtJ0

https://www.youtube.com/watch?v=DP24BceOwt8

https://www.youtube.com/watch?v=RKkC2JpjaGc
The Hunters and the Hunted

https://www.youtube.com/watch?v=0WbjCbdw9kc