Transcript Ecology review:

Ecology review:
What is Ecology? (a
brief review)
• Ecology• the study of interactions between
– organisms and organisms
– organisms and their environment
Where do we fit in?
(What is our environment?)
The Biosphere!
Factors that effect us:
1. Abiotic Factors
Moisture
Wind/Air currents
Light
Temperature
Soil
• A• Bio-
stands for non
stands for living
• Abiotic Factors-
nonliving factors
2. Biotic Factors:
• Biotic- Living factors
What is the organization of
Ecological Study?
Organism
Population
Community
Ecosystem
Biosphere
Levels of Organization
• Individual- one
organism (living)
• Ex a moose
Levels of Organization
• Population- groups
of individuals that
belong to the species
and live in the same
area. (living-living
same species)
• Ex many moose
Levels of Organization
• Community- groups of
different populations
(more than one
population or different
groups of species)
Ex many groups of
moose beavers, trees,
grass (all living)
Levels of Organization
• Ecosystem- all
organisms in a
particular area along
with the nonliving.
(living and nonliving)
Ex many groups of
moose beavers,
trees, grass, rocks,
water, mountains
Levels of Organization
• Biome- group of
ecosystems that have
the same climate and
similar dominant
communities
• Biomes: tropical rain forest,
tropical dry forest, tropical
savannah, temperate
grassland, desert, temperate
woodland and shrubland,
temperate forest,
northwestern coniferous
forest, boreal forest (taiga),
tundra, mountains and ice
caps
Levels of Organization
• Biosphere- all of the
planet where life
exhists, includes land,
water, and, air
• Life extends 8 km up
and 11 km below the
surface
IN AN ECOSYSTEM:
Organisms live in a Habitat
Organisms fit into a Niche of
the environment
Habitat vs. Niche
• Habitat- an area where an organism lives
• Niche- an organisms role in its environment
– The Long Version  full range of physical and
biological conditions in which an organism lives and
the way in which the organism uses those conditions.
Includes where in the food chain it is, where an
organism feeds
• Habitat is like an address in an ecosystem and
a niche is like an occupation in an ecosystem.
ENERGY FLOW
Autotrophs vs. Heterotrophs
Energy Flow (Trophic Levels)
• Producers- make
their own food
• Consumers- get
energy from
consuming producers
Producers
• Producers- capture
energy from sunlight
or chemicals and use
the energy to produce
food.
• Producers are
autotrophs- they
make food from their
environment
2 main types of autotrophs
• One type gets energy
• Another type gets
from the sun-by
energy without
photosynthesis
light- by
chemosynthesis
Consumers
• Consumers are
heterotrophs- get
energy from other
organisms
Types of Consumers
•
•
•
•
Herbivores- eat only plants
Carnivores- eat animals
Omnivores- eat both plants and animals
Detritivores- eat dead matter (plants and
animals)
Feeding Relationships
• Energy flows through an ecosystem in one direction
from:
–
–
–
–
1. the sun or inorganic compounds
2. To autotrophs (producers)
3. To heterotrophs (consumers)
Decomposers get energy from decomposing dead
organisms
Food Chain- a series of steps in which organisms
transfer energy by eating or being eaten.
Food Web- A network of
feeding relationships.
(More realistic that a food
chain)
Food Web
They can
become
very
complex!
Trophic levels
• Each step in a food chain
or a food web is called a
trophic level.
– Producers are the first
trophic level
– Consumers are the
second, third, or higher
trophic level
• Each trophic level
depends on the one
below for energy
Energy Pyramid
• Only part of the energy
stored in one level can be
passed to the next- most
energy is consumed for
life processes
(respiration, movement,
etc., and heat is given off)
• Only 10% of the energy
available within one
trophic level is transferred
to organisms in the next
trophic level
Biomass Pyramid
• Biomass- the total
amount of living
tissue within a given
trophic level.
• A biomass pyramid
represents the
amount of potential
food available for
each trophic level in
an ecosystem.
Energy Losses
• Energy transfers are never 100 percent
efficient
• Some energy is lost at each step
• Limits the number of trophic levels in an
ecosystem
• Energy flow is a one way path! (not a cycle)
All Heat in the End
• At each trophic level, the bulk of the
energy received from the previous level is
used in metabolism
• This energy is released as heat energy
and lost to the ecosystem
• Eventually, all energy is released as heat
Biogeochemical Cycles
(Matter moving through the environment)
• All living organisms need certain
elements/compounds for life processes
– Ex: your cells need C,H,O,P,N & S in order to
live and reproduce (make more cell)
• Cycles in nature keep these elements
“moving” from organisms to organism (and
sometimes into the atmosphere)
Biogeochemical Cycles
(Matter moving through the environment)
• The flow of a nutrient from the environment to living
organisms and back to the environment
• Main reservoir for the nutrient is in the environment
• Transfer rates to and from reservoir are usually lower
than the rates of exchange between and among
organisms.
• Matter is recycled through an ecosystem – not one way
flow
Three Categories
• Hydrologic cycle
– Water
• Atmospheric cycles
– Nitrogen and carbon
• Sedimentary cycles
– Phosphorus and sulfur
CYCLES IN NATURE
Carbon Cycle
• Carbon moves through the atmosphere
and food webs on its way to and from
the ocean, sediments, and rocks
• Sediments and rocks are the main
reservoir
Carbon Cycle
diffusion
Atmosphere
Bicarbonate,
volcanic action
carbonate
Marine
food
TERRESTRIAL
webs ROCKS
Terrestrial
Rocks
photosynthesis
Land Food
Webs
Soil Water
Marine Sediments
weathering
Peat, Fossil
Fuels
Carbon in Atmosphere
• Atmospheric carbon is mainly carbon
dioxide
• Carbon dioxide is added to
atmosphere
– Aerobic respiration, volcanic action,
burning fossil fuels, decomposition of
organic materials
• Removed by photosynthesis
Nitrogen Cycle
•
Nitrogen is used in amino acids and nucleic acids
(all living organism need nitrogen to make
proteins)
•
Main reservoir is nitrogen gas in the atmosphere
•
Decomposers are vital to convert ammonia into:
1. usable nitrites & nitrates for plants (nitrogen fixation)
2. nitrogen gas (denitrification = puts it back into the atmosphere)
Phosphorus Cycle
• Phosphorus is part of phospholipids and all
nucleotides
– What are these?
• It is the most prevalent limiting factor in
ecosystems
• Main reservoir is Earth’s crust; no gaseous
phase (it never enters the atmosphere – like
carbon and nitrogen)
Phosphorus Cycle
mining
excretion
FERTILIZER
GUANO
agriculture
uptake by
autotrophs
MARINE
FOOD
WEBS
weathering
DISSOLVED
IN OCEAN
WATER
uptake by
autotrophs
weathering
DISSOLVED IN
SOILWATER,
LAKES, RIVERS
death,
decomposition
sedimentation
death,
decomposition
leaching, runoff
setting out
uplifting over
geolgic time
MARINE SEDIMENTS
ROCKS
LAND
FOOD
WEBS