Transcript Ecology and Ecosystems

ECOSYSTEMS:
COMPONENTS, ENERGY
FLOW & MATTER CYCLING
CHAPTER 4
ECOLOGY
 Study of the relationships between
organisms and their environment
– How organisms interact with their nonliving
environment such as sunlight, temperature,
moisture, nutrients, etc.
 KEY WORK IS: INTERACT -
Connections in Nature
 What is an organism?
 What make up organisms?
Organisms are either:
 EUCARYOTIC – SURROUNDED BY A
MEMBRANE
– HAVE A DISTINCT
NUCLEUS
– HAVE INTERNAL
ORGANELLES
– All organisms except
bacteria.
 PROCARYOTIC – SURROUNDED BY A
MEMBRANE
– NO DISTINCT
NUCLEUS
– NO INTERNAL
PARTS
SURROUNDED BY
MEMBRANES
– Bacteria
 What is a SPECIES?
 Number of species on
 How do species differ?
earth is not known
 What is the difference
– 5 million to 100
million maybe
between sexual and
asexual reproduction?
 Wild species - found
in natural habitat
 Domestic species have been taken and
therefore play a
smaller role.
Population
 A group of organisms of the same species in
a given area at a given time
– Can vary with:
• Season
• Time of day
• Time of year
 Density = number of organisms/area
 What is genetic diversity?
What is habitat?
 Where an organism lives
What is a Community?
 Populations of all species in a particular
place at a particular time.
What is an Ecosystem?
 Community of different species interacting
with one another and with their nonliving
environments.
 Ecosystems can be small or large.
 What is the Biosphere?
lithosphere
Atmosphere
hydrosphere
Make up the Biosphere
What makes up the Atmosphere?
 Troposphere - 0-11 miles up - contains our
air.
– What are the major gases that make up the air
we breathe?
 Stratosphere - 11-30 miles up - lowest
portion contains the ozone layer
– What is the purpose of the ozone layer?
What is the Hydrosphere?
 Liquid water - surface and underground
 Ice
 Water vapor in the atmosphere
Interior of earth:
 Core - mostly iron, some nickel
– Center solid surrounded by a liquid core of
molten material
 Mantle - mainly iron with some Si, O,& Mg
– Mostly solid rock except for asthenosphere
which flows like plastic.
 Crust - thinnest zone - 98% of it is only 8
elements
Life is sustained by:
 One -way flow of energy - from sun through
plants to animals - then back into space
 Cycling of matter or nutrients
 Gravity - allows planet to hold its
atmosphere.
 Earth is a closed system - receives energy
from sun but loses no matter into space
– Nutrients are recycled
 Organisms are open systems - exchange
matter and energy between the system and
the environment.
– Take in matter and energy - use it to stay alive
and put waste back into the environment.
How does the sun sustain life?
 Lights & warms the planet
 Supplies energy for photosynthesis
 Powers cycling of matter
 Drives the climate and weather systems
Facts about the sun
 Middle- aged star
 Takes 8 minutes for light to get to the earth
 Most of light to earth is ultraviolet
 About 28% of its light is reflected back into
space by clouds, dust, and land
 72% warms air and land, evaporates water,
generates winds,
 Only about .023% is used by plants for
photosynthesis
Nutrient cycles
 Nutrient - any atom,
ion or molecule an
organism needs to live
 Macronutrients are
needed in large
amounts - CHONPS
and a few others
 Micronutrients needed in small or
trace amounts.
 Also called
Biogeochemical
cycles. - life - earth chemical cycles.
– Driven by the sun
– Main ones are
hydrologic,
nitrogen,carbon,
phosphorus, and sulfur.
Ecosystem Concepts
 Biomes - large regions
characterized by
climate and life-forms
- especially vegetation
 Climate - long term
weather - mainly
temperature and
precipitation.
 Aquatic life zones -
freshwater & marine
– Lakes & streams
– Estuaries, coastlines,
coral reefs, & deep
ocean.
Ecosystem concepts
 Ecotone - a region
where two ecosystems
meet.
– Has more species
diversity than either
adjacent ecosystem.
 Biotic - living
components - plants
and animals
 Abiotic - nonliving
components - water,
nutrients, air, solar
energy, etc.
Range of Tolerance
 Ability to survive within variations of a
physical or chemical environment
– Individuals within a population may have
differing ranges of tolerance
 Tolerance limits - beyond which no member
of a species is able to survive
Range of Tolerance
Abundance of organisms
Upper limit
of tolerance
Few
No
organisms organisms
Population Size
Lower limit
of tolerance
No
Few
organisms organisms
Zone of
Zone of
intolerance
physiological stress
Low
Optimum range
Temperature
Zone of
Zone of
physiological stress
intolerance
High
Limiting Factors
 Any one factor that is responsible for
regulating population growth
– Light, water
– In aquatic ecosystems
• D.O.
• Sunlight
• Temperature
What is photosynthesis?
 The producers (plants) also called
autotrophs take carbon dioxide, water, and
sunlight and produce glucose and oxygen.
 Chemosynthesis in the ocean uses heat
energy from the thermal vents to convert
dissolved hydrogen sulfide and carbon
dioxide into organic nutrient molecules.
What is trophic level?
 The feeding level of
the organism.
 Plants are
 __________________
 They are the
 __________________
in an ecosystem.
 They occupy the
 _______________
 Trophic level.
 Cows are
__________________
which are
________________
 Consumers. They
occupy the
______________
 Trophic level.
 Lions are
 __________________
 They are
 _____________
 Consumers.
 They occupy the
 ___________trophic
level.
 Pigs are _______
 Which means they eat
 ______and ______;
 Sharks are ______
 Which means they eat
 __________
What are DETRITIVORES?
 What are
decomposers?
 What are detritus
feeders?
What is AEROBIC RESPIRATION?
 Uses _____ + ______ and releases _____
_______, ______, and _______
What is AEROBIC RESPIRATION?
 Uses glucose + oxygen and release carbon
dioxide, water, and energy.
 All organisms carry on respiration!!!
What is Anaerobic Respiration?
 Also called fermentation.
 Does not use free oxygen
 The end produces are compounds such as
methane gas, ethyl alcohol, acetic acid, and
hydrogen sulfide.