Download Ecology

Ecology
The scientific study of the
interactions between organisms and
their environment
Components of the
Environment
• Abiotic Factors—Non-living
components; temperature, light, water,
nutrients
• Biotic Factors—Living components; all
organisms; predators, prey, parasites,
hosts, mutualistic bacteria, disease causing
microbes, etc.
Biosphere
Ecosystems
Communities
Populations
Organisms
Factors Affecting the
Distribution of Organisms
Factor #1--Dispersal
• Is there a barrier that prevents an organism
from entering an area? Is the area
accessible?
• Many species have been “transplanted” and
are known as introduced or exotic species.
• Examples include the African honeybee,
kudzoo, the zebra mussel
The Tens Rule
• One of ten introduced species become
established
• Of the one in ten that become established,
one becomes common enough to
become a pest
Factor #2--Behavior
• If they are physically able to disperse, do
reproductive or other behaviors prohibit
them from occupying specific areas.
• Example: Anopheles mosquito are
SPECIFIC to a breeding place; they could
breed in any water area—they have
access—however, they choose to breed in
SELECT areas.
Factor #3—Biotic Factors
• Negative interactions with other organisms
(predation, disease, competition) may limit
the dispersal of organisms
Factor #4—Abiotic Factors
• Temperature, rainfall, salinity, light, wind,
rocks, soil, water, etc.
• Climate—temperature, water, light, and
wind—greatly determines dispersal of
organisms
• Biomes—Major types of ecosystems tahta
occupy broad geographic regions—
usually defined by abiotic factors
Aquatic Biomes
• Cover 75% of Earth’s surface
• Marine biomes—have 3% salt
concentration
• Freshwater biomes—have less than 1% salt
concentration
Aquatic Biomes
• Contain photic zone (sufficient light for
photosynthesis) and aphotic zone (little light
penetrates)
• Sun warms surface waters but deeper waters are
cold
• Thermocline—area of rapid temperature change
• Benthic Zone—bottom of all aquatic biomes;
occupied by communities of organisms known
as benthos that feed on detritus—dead organic
matter
Freshwater Biomes
• Standing bodies of water & moving bodies
of water
• Littoral Zone—Shallow, well lit waters
near shore—plants grow here
• Limnetic Zone—Well-lit open surface—
phytoplankton thrive here
• Profundal zone—Deep, aphotic region
• Benthic zone—The bottom
Types of Lakes
• Oligotrophic--Deep & nutrient poor; not
very productive; waters clear
• Eutrophic—Shallower, with high nutrient
content, very productive; waters mirky
Other Aquatic Ecosystems
• Wetland—Area covered with water that
supports aquatic plants; marshes, swamps,
and bogs
• Estuaries—Area where a freshwater stream
or river merges with the ocean; ex. Salt
marshes
Marine Ecosystems
• Intertidal zone—Zone where land meets
water
• Neritic Zone—Shallow regions over the
continental shelves
• Oceanic Zone—Area past the continental
shelf—also called open sea
• Pelagic Zone—Open water of any depth
• Benthic Zone—Sea Floor
Terrestrial Biomes
• Namd for major physical of climatic
features and for their predominant
vegetation
Tropical Forest
Savanna
Desert
Chaparral
Temperate Grassland
Temperate Deciduous Forest
Coniferous Forest
Tundra