Transcript Ecology Notes - Bremen High School District 228

Ecology Notes
2012
Ecology:
The study of
interactions
between organisms
and their
environment
Levels of Organization
Biosphere
All parts
of the
planet
that
contain
life
Biome
Group of
ecosystems
with the
same
climate and
communities
Ecosystem
Living (biotic) and non-living
(abiotic) aspects that
interact in a given area
Community
Different
population
that live
and
interact in
a given
area.
Population
Group of
organisms of
the same
species that
live in the
same area
and compete
with each
other for
resources
Organism
One
individual
of a
species
Factors in the Environment
Biotic Factors: Any living part
of the environment
Examples: bacteria, animals,
plants, insects
Abiotic Factors: Any non- living
part of the environment
Examples: hours of sunlight,
type of soil, rainfall
Niche
• an organisms job in the environment
Niche
Niche
Habitat
• Where an organism lives
African Elephant
Great Black-backed gulls
Biomes of the world
Tundra
1/3
• Arctic Tundra
cold year round, -34o to 12oC
Permafrost – ground never thaws out
dry, 12 to 20 cm per year
• Alpine Tundra
• long, cold winters with short, cool summers
• a little rain, lots of snow
• Mountainous – high altitude with no trees
Tundra
2/3
• Location:
northern N. America, Asia and
Europe, polar ice caps
• Climate
-40˚C to 18˚C
15-25cm or less annual rain
• Unique Characteristics
• Coldest biome
• Means treeless
• Low biotic diversity
Tundra
3/3
•Animals
snowy owl, caribou, arctic fox,
lemmings and small rodents
Arctic: (N) polar bears, seals, insects,
and mites (S) penguins
•Plants
ground-hugging like mosses,
lichens, sedges, and short
grasses
•Arctic: (N) mosses and lichens
Desert
1/3
• Hot/Dry: Am. West, Central and South Am.,
Africa, Australia, Mexico, Middle East
• Semi Arid: West Coast of California,
Russian steppes, Southern Europe,
North Asia
• Coastal: Chile
Cold: Greenland
Desert
2/3
• Makes up 1/5 of Earth’s surface
• Plants and Animals are well adapted to
the dry environment
• Climate: Hot days (49oC) followed by
cold nights (20oC)
• Ann Precipitation: dry, less than 25 cm
per year
Desert
3/3
• Unique Characteristics
• Variable temperatures
• Soils rich in minerals but poor in organic
material
• Animals
• Mountain lions, gray foxes, bobcats,
antelopes, kangaroo, bats, owls, hawks,
and roadrunners, ants, beetles,
rattlesnakes and lizards
• Plants
• Cacti, creosote bush,
other plants with short
growing cycles
Grassland
• Covers ½ of Africa (5 million mi2)
• Examples
– Tropical Savanna
Australia)
– Temperate
Europe)
(E. Africa, S. Brazil, N.
(C. Asia, N. America, Australia, C.
Tropical/Savanna
Climate: (20o to 25oC)
-warm year round
-seasonal rainfall
-rich soil
Ann. Precipitation: 50 to 125 cm/year
Animals: lions, tigers, leopards, cheetahs,
elephants, giraffes, zebras, termites,
pelicans, monitor lizards
Plants: tall grass (savanna), tall deciduous
trees, orchids, bromeliads (tropical)
Temperate
• Climate:
winter (-4oC),
spring, summer (38oC), fall
-fertile soils
• Ann. Precipitation:
50 to 90 cm/year rain and snow
• Animals
coyotes, badgers, wolves, grizzly bears,
rabbits, bison, owls, snakes, grasshoppers
• Plants
lush, perennial grasses and herbs
Tropical Rainforest
1/2
• Greatest species diversity
• Found in areas near the equator,
hot and wet yr round
• Thin, nutrient-poor soils
• Climate: warm year round
(20o to 25oC)
• Ann Precipitation:
– 200 + cm/year
Tropical Rainforest
2/2
• Animals
sloths, jaguars, anteaters, monkeys,
parrots, butterflies, piranhas, boa
constrictors, anacondas
• Plants
ferns, large woody vines, orchids,
bromeliads, climbing plants, broadleaved evergreen trees
Temperate Forest
(Deciduous)
• 4 seasons, fertile soil
• Climate: changes
dramatically with the seasons
(-30o to 30oC)
• Ann. Precipitation: 75 to 150cm/year
rain and snow
• Animals: deer, black bear, squirrels,
raccoons, skunks, turkeys
• Plants: deciduous trees, some conifers,
flowering shrubs, herbs, ground layer of
mosses and ferns
• Location: E. U.S., SE Canada, most of Europe,
parts of Japan, China, and Australia
Taiga(Boreal)
Low temperatures
High humidity
N. Am., Asia, N. Europe
Acidic, nutrient-poor soil
Climate: short cool summers, long
cold winters
• Ann. Precipitation: 40 to 100
cm/year, mostly snow
• Key Trait: Evergreen Trees
•
•
•
•
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Aquatic
• Freshwater – “sweet”
water, able to drink
• Marine – salt water,
unable to drink, covers
3/4 of Earth’s surface
Freshwater
• Standing Water
– Lakes and Ponds
• Flowing Water
– Rivers and Streams
Marine (ocean)
Photic Zone = Light penetrates
Intertidal Zone
-exposed to tides and air
-snails, sea stars, sea urchins,
seaweed,
Coastal Ocean
-plankton, kelp forests, sea
otters, seals, whales, variety
of fish
Aphotic Zone = no light
• Open Ocean
• Ocean trench
• Chemosynthetic
autotrophs are
only producers
that survive
Coral Reef
Warm,
shallow,
water with
diverse
environments
Estuaries
Ecological
Succession
Succession
• Changes that occur in a community over time
Primary Succession
New, bare land
with no soil
The first species to exist in the
environment are the
Pioneer species
The ecosystem will
continue to develop until
a climax community has
been reached
A climax community is a
mature, stable community
Secondary Succession
Occurs when there is a disturbance in the
community
(Examples follow)
Natural Disasters
Animals
Abandonment
Biotic Factors
Flow of Energy
0.1%
1.0%
10%
100%
Producers
=
Autotrophs
Consumers = Heterotrophs
Herbivores
Carnivore
Omnivore
Humans are
Omnivores
Detritivore
Decomposer
Food Chains are a “unidirectional”
flow of energy
Each step in a food chain is called a
trophic level
Food Webs are linked food chains
within an ecosystem
Abiotic Factors
Sun
Source of all energy
in an ecosystem
Biogeochemical Cycles
Connects the biological, geological,
and chemical aspects of the biosphere
Water Cycle
Evaporation- land (liquid) to air (gas)
Transpiration – plants (liquid) to air (gas)
Condensation – air (gas) to liquid droplets
Precipitation – falls from sky
Carbon Cycle
Biological Processes
Photosynthesis – carbon dioxide in oxygen out
Respiration – oxygen in carbon dioxide out
Decomposition – carbon released into environment
Geochemical Processes
Erosion – movement of geological materials (like carbon)
Volcanic Activity – volcanoes release gases (including carbon)
Biogeochemical
Burial/Decomposition – fertilizes (puts carbon into)
the land and creates fossil (carbon based) fuels
Human Actions
Mining – releases carbon from
ground
Deforestation – cutting/burning
trees and releasing their carbon
Burning Fossil Fuels – releases
carbon into the air
Nitrogen Cycle
Nitrogen is needed to
produce amino acids
to build proteins
Nitrogen makes up 78% of Earth’s atmosphere
Most nitrogen is in an unusable form and
must be “fixed” by Legumes (bean type) plants
and/or bacteria in order to enter into the cycle
Phosphorus Cycle
Major component of nucleic acids
Not found in the
atmosphere,
only in the land
Mostly absorbed by
plants and then
cycled through the
ecosystems
through food webs
Symbiotic Relationships
Symbiosis is a close relationship
between two organisms
Predation: one organism
captures and feeds on another
Parasitism: One
organism lives on/in
another causing it harm
Commensalism: one
organism benefits, the
other is neither helped nor
harmed
Mutualism: both
organisms benefit
Competition: struggle
for resources
Scavenging: Feed off
dead/decaying organisms
Populations
Group of organisms of the same
species in same area
Characteristics of a Population
1. Geographic Distribution: area inhabited
by a population (range)
2. Population Density: # of individuals
per unit area
3. Growth Rate: change in
size of a population (+/-)
Population Growth is Affected by:
1. Birth Rate
2. Death Rate
3. Immigration/Emigration
Types of Population
Growth
1. Exponential Growth
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Individuals reproduce at a constant rate
Under ideal conditions with unlimited resources,
populations will grow without limit
J-shaped curve
2. Logistic Growth
-Occurs when population’s growth slows/stops
following a period of exponential growth
-Ceases once carrying capacity is reached
Limiting Factors
1. Density Dependent
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Limits population growth based on population
size
Example: disease, competition, stress, predation
2. Density Independent
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Limits growth regardless of population size
Example: temperature, extreme weather, floods,
drought, natural disaster, habitat destruction