Transcript Ecology PowerPoint

Chapter 3: The Biosphere
What is ecology?
Ecology
• Ecology – the study of interactions among
organisms and between organisms and
environment (Haeckel, 1866)
• Interdependence – dependence between or
among individuals or things
Levels of Organization
1. Biosphere – largest
level, our entire
planet - portions of
planet where life
exists (land, H2O, air)
– 8 km above to 11 km
below
Levels of Organization
2. Biome – group
of ecosystems
that share
similar climates
(temp. and
rainfall)
Levels of Organization
3. Ecosystem – collection of all organisms in
a particular place together with the abiotic
(physical) environment.
Levels of Organization
4. Community – groups of different populations
that live together in a defined area.
5. Population – groups of individuals of same
species that live in same area.
6. Species – group of organisms that can breed and
produce fertile offspring.
Levels of Organization
Biotic and Abiotic Factors
• Biotic – living part of the
environment
– Plants, Animals ,Mold, Fungi,
Bacteria, Protist
• Abiotic – Nonliving part of
the environment
– Sunlight, heat, soil, wind,
water, temperature
• Environment – all conditions or
factors surrounding an organism;
includes both biotic and abiotic
factors.
3.2 Energy, Producers, and
Consumers
At the core of every organism’s interaction
with the environment is its need for
ENERGY to power life’s processes
Producers (Autotrophs)
• Can trap energy to produce food
• Use solar or chemical energy to produce food by
assembling inorganic compounds into complex organic
molecules
– Plants
– Some protist
– Some bacteria
Primary Producers
• Photosynthesis – captures solar energy and
converts it to chemical energy
sunlight
6CO2 + 6H2O  C6H12O6 + 6O2
• Chemosynthesis – Chemical energy used to
produce carbohydrates
– bacteria in harsh environments
– deep sea volcanic vents or hot springs
Consumers (Heterotrophs)
• Can’t trap energy directly;
must acquire it from other
organisms
– Herbivores – eat plant leaves,
roots, seed or fruits (cow,
catepillar, deer)
– Carnivores – eat other animals
(snakes, dogs cats)
– Omnivores – eat both plant and
animal (human, bear, pigs)
Consumers (Heterotrophs)
• Scavengers – consume
carcasses of other animals
(vultures and hyenas)
• Decomposers – break down
organic matter (bacteria and fungi)
– produces detritus (small pieces
of dead and decaying plant and
animal remains)
• Detritivores – feed on detritus
(earthworms and many types of
snails, mites, shrimp, crabs)
3.3 Energy Flow
in Ecosystems
 Food Chains
 Food Webs
How Ecosystems Work (3:23)
Food Chains and Food Webs
SUN
Autotrophs
Heterotroph
1. Food Chain – energy trapped by producers
passed on when organisms eat and are eaten
2. Food Web – relationship more complex than a
chain
Food Web Activity
Trophic Levels and Ecological Pyramids
• Trophic Levels – each step in a food chain/web
Ex: producers, then consumers
• Ecological Pyramids – shows relative amount of
energy at each trophic level of a food chain or web.
• Biomass – total amount of living tissue within a trophic
level
3.4 Cycles of Matter
*Recycle Matter*
Carbon Cycle
• Photosynthesis – uses CO2 from atmosphere
– Happens in the CHLOROPLAST
6CO2 + 6H2O
C6H12O6 + 6O2
• Respiration – returns CO2 to atmosphere
– Happens in the MITOCHONDRIA
C6H12O6 + O2
H2O + CO2
Carbon Cycle
The Carbon Cycle
1. Volcanoes, respiration, fossil fuels, and
decomposition add CO2 to atmosphere.
•
•
Organic carbon is locked deep beneath the Earth’s surface – high pressure
converts layers of sediment (dead organisms and waste) to carbon-rich fossil
fuels.
Fossil fuels are extracted and processed to make gasoline and oil –burning
fossil fuels release CO2
2. Plants take CO2 and make carbohydrates glucose (C6H12O6).
3. Plants are eaten by animals and carbohydrates are
passed through the food chain.
4. As the animal breathes and eventually dies and
decomposes, CO2 is returned to the atmosphere.
Carbon Cycling
Water Cycle
Water Cycle
1. Water enters the atmosphere by:
•
•
Evaporation – water changes from a liquid to a
gas
Transpiration – Evaporation through leaves
2. As water rises it cools condenses into tiny
droplets that form clouds.
3. Droplets returns to Earth as precipitation.
4. Water enters the rivers, ground water,
ocean or plant roots to restart cycle.
Nitrogen Cycle
Nitrogen
NitrogenCycle
Cycle
1. Nitrogen gas makes up 78% of atmosphere
2. Nitrogen Fixation: bacteria take nitrogen
gases and turn it into ammonia, nitrite, and
nitrate.
3. Plants and animals use nitrate to make
amino acids.
4. Animal dies and decomposes returning
nitrates to the soil.
5. Denitrification: other bacteria convert
nitrates into nitrogen gas.
The Phosphorus Cycle
The Phosphorus Cycle
• Phosphate – parts of DNA/RNA
• Found in rocks that are worn down
• Washes into rivers/streams/oceans
for marine organisms
• Taken in by plants and turned into
organic compounds
Nutrient Limitation
• Primary Productivity – the rate at which
organic molecules are created by producers
• If nutrients are in short supply, they are
called LIMITING NUTRIENTS
Ex: Nitrogen is often limiting in water; if
there is suddenly as input of N (fertilizer
runoff), organisms can grow rapidly (Algal
Bloom)
Chapter 4: Ecosystems and
Communities
4-1 The Role of Climate
Climate
• Climate: long-term,
over entire biome area
– Weather: short-term,
local
• Greenhouse Effect
– It’s a good thing!
– CO2, H2O, CH4 all trap
heat and hold it next to
the surface
– Keeps the temperature
suitable for life
Video Clip 1
Video Clip 2
The Effect of Latitude on Climate
• Earth has 3 climate zones due to unequal
heating because of the angle of the sun
– Polar
– Temperate
– Tropical
Heat Transport
• Ocean and wind
currents help produce
Earth’s climates
• They are affected by
land masses and
Earth’s rotation
4-2 Niches and Community
Interactions
The Niche
• Niche – where and how something lives; the way the
species obtains what it needs to survive and reproduce
– Habitat is the general place where an organism live
(address)
– Niche is the organism’s how it interacts with biotic
and abiotic factors (occupation)
Community Interactions
1. Competition
•
Organisms compete for resources
Ex: Food, Mates, Shelter
•
Competitive Exclusion Principle
– no 2 organisms occupy exactly
the same niche in exactly the same
habitat at exactly the same time.
•
winner and a loser
2. Predation
•
One organism (predator) captures
and feeds on another (prey).
Community Interactions
3.
•
Symbiosis
Mutualism – both species benefit
Ex: Flowers & insects, Clown Fish &
Sea Anemone, Egrets & Alligators
•
Commensalism – one benefits,
the other is not helped nor
harmed
Ex: Barnacle (gets food) & Whale
•
Parasitism – one benefits, other
is harmed
Ex: tapeworms, fleas, ticks, lice
Examples of Symbiosis
5 min video
Bed bugs
Aphid – destructive insect pests
Grey shark with pilot fish
4.3 Ecological Succession
Ecological Succession - change in an ecosystem
1.
Primary Succession – no remnants of an older community
(volcanic eruption, glacier erosion = reveals bare rock)
o 1st species to colonize barren areas are called
“pioneer species”
oEx: algae, fungi, lichens - composite, symbiotic
organisms
2.
3.
Secondary Succession – disturbance affects the community soil exists (flood, hurricane, wild fires, clear cutting, plowed
for farming)
Climax Community – fairly stable, dominant community
established after succession.
Intro to Biomes
4-4 Land Biomes
Biomes based on
Precipitation and Temperature
Videos on Biomes
• Terrestrial Biomes: Deserts, Grasslands,
and Forests (3:39)
• Savanahs (2:36)