Download Ecology

Ecology
Objectives:
• To understand ecological levels of organization.
• To describe the flow of energy through an
ecosystem.
• To describe and analyze the components of the
water, carbon, nitrogen and phosphorous cycles.
• To identify the effects that destruction of habitats,
pollution, urbanization, and natural disasters have on
population.
What is ecology?
• The scientific study of relationships between
organisms and their environment.
• It explains how living organisms affect each
other and the world they live in.
Why is ecology important?
• Allows us to understand how the natural
world around us works
• Allows us to understand how organisms
(plants & animals) are shaped by their
surroundings (environment)
Ecology Issues Today
• Exploding Human
Population
• 6 billion people in 1996
• 7.8-12.5 billion people
by the year 2050
• More of the Earth’s
resources necessary to
support humans
• Food, space, energy
The Sixth Mass Extinction
• Human impact has
destroyed the habitats
of many bird species.
• Hawaii, 60 species now
extinct
The Thinning Ozone Layer
• Ozone layer protects
Earth’s living organisms
by absorbing UV
radiation.
• Hole: low ozone level
over Antarctica
• Sunburns and skin
cancer
Climatic Changes
• Greenhouse Effect: gases in the atmosphere trap
heat emitted from the Earth’s surface, insulating and
warming the Earth
• Burning fossil fuels releases gases that trap heat in
the atmosphere. (carbon dioxide, methane, & nitrous
oxide) As these gases build up, they trap more heat
near the Earth’s surface, causing Earth’s climate to
become warmer than it would naturally.
Interconnectedness
• Key Theme: All organisms affect and are
affected by the living and non-living
components of their environment
• The next slide shows different species that are
ecologically connected. Describe some ways
they are connected.
How is the environment organized?
•
The parts of an environment are organized
into two categories:
1. Abiotic Factors
2. Biotic Factors
Nonliving Environment
• Abiotic Factors (A=“not” Bio= “living”)– the
nonliving parts of an organism’s environment
• Abiotic factors affect an organism’s life
• Examples:
• Soil, temperature, pH, sunlight
• Precipitation, air currents, and humidity
Living Environment
• Biotic Factors: All the living parts of an
environment
• All organisms depend on others, directly or
indirectly, for food, shelter, reproduction, or
protection.
• Examples: competitors, decomposers, and
predators
Biotic or Abiotic?
• Abiotic
Biotic or Abiotic?
Biotic
Biotic or Abiotic?
Abiotic
Biotic or Abiotic?
Biotic
*Phosphorus
*Calcium
Potassium
*Nitrogen
*Sulfur
Biotic Factors?
Abiotic Factors?
Levels of Organization
• Now that you can identify biotic and abiotic
factors, we will organize their interactions at
different levels
• Ecologists have arranged an organism’s
interactions into different levels according to
complexity.
Levels of Organization
1st Level: Organism
• The simplest level in
ecological organization
• An organism is an individual
living thing.
• Bacterial cell or elephant
• Scientists study the
adaptations that allow
organisms to overcome
challenges of their
environment
2nd Level: Population
• A group of organisms, all
the same species, which
interbreed and live in the
same place at the same
time
• Scientists study the
members of a single
species; how they share
their environment. (Food,
water, etc.)
3rd Level: Community
• Biological Community is
made up of all the
populations of different
species that live in the
same place at the same
time; all biotic factors
• Here: zebras and
wildebeest
• Scientists study how the
species interact
4th Level: Ecosystem
• All the biotic and abiotic
parts of an environment
found in a particular
place.
• Populations of plants
and animals that
interact with each other
in the same place and
the abiotic factors of
that area.
Ecosystem
• Two Types:
1. Terrestrial (Land)
2. Aquatic (Water)
a. Freshwater (lakes, ponds, rivers)
b. Saltwater/Marine (oceans)
5th Level: Biosphere
• The portion of Earth
that supports life (13
mi. thick)
• Life is found in air, on
land, and in fresh and
salt water
• If the Earth were the
size of an apple, the
biosphere would be as
thick as the apple’s skin.