Transcript Principles of Ecology

Ecology
Chapters 2, 3, 4 & 5
Ecology….
study of the interactions
things with each other
and with their environment
of living
BIO-TIC FACTORS/COMPONENTS –
living or once living things
A-BIO-TIC FACTORS/COMPONENETS –
the physical, nonliving environment
In this scene,…
What is biotic?
What is abiotic?
Biotic or Abiotic?
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Feathers
Rocks
Soil
Water
Grasses
Fungi
Bones
Temperature
Habitat and Niche
habitat – address of organism; where an
organism lives
niche – job of an organism; role(s) it plays in
its environment
What is the
niche and habitat
of each bird?
Indigo Bunting
Is it the same
for each?
Eastern Bluebird
Scarlet Tanager
In a field ecosystem
what are some….
biotic factors?
abiotic factors?
niches?
habitats?
Levels of Organization - Hierarchy of Life
• Organism: (simplest level): a single living things
SPECIES - structurally similar organisms that naturally
interbreed and produce fertile offspring
• Population: all the members of a single species in a given area
• Community: all the different living things in a given area
• Ecosystem: composed of all the biotic and abiotic factors
in an area
• Biome: ecosystems having a characteristic climate and
characteristic organisms
• Biosphere (broadest/largest level): includes all areas of the Earth
where life exists
BIOSPHERE
All areas
of the
Earth
where life
exists
Community Interactions
(interactions between the species living in an area)
• Competition
• Predation
• Symbiotic Relationships (symbioses)
– Mutualism
– Commensalism
– Parasitism
COMPETITION
• Results from niche overlap
• Organisms compete for food,
water, mates and habitat
• Competitive Exclusion may
occur: where one species is
eliminated
What would these zebra compete for?
PREDATION
Results when…..
• 1 individual kills another (predator)
• 1 individual is killed (prey)
• One way that natural selection occurs
Examples…
hawk  snake
lion  gazelle
fox  rabbit
Anti-Predator Adaptations or Defenses
Almost all organisms are vulnerable to predation , therefore,
developing adaptations that serve as defenses are an
advantage…such as…
– Camouflage
– Mimicry
– Warning Coloration
– Protective Coverings
– Secondary Compounds
CAMOUFLAGE
coloration or patterns that
blend in
with the surroundings
MIMICRY
a harmless species resembles (copies)
a venomous or distasteful species
Warning Coloration
characteristic of a poisonous or unpalatable organism
serves to warn off potential predators
Protective Coverings
intended to protect from damage or injury
Secondary Compounds
chemicals that are poisonous, irritating, or distasteful
Example: poison ivy
Types of Symbioses…
Mutualism…. both organisms benefit
Commensalism…. one benefits
one is unaffected
Parasitism…. one is harmed (HOST)
one benefits (PARASITE)
PARASITISM
ECTO-PARASITES - live outside the host
(ticks, fleas, lice)
ENDO-PARASITES – live inside the host
(bacteria, protists, worms)
Hosts have evolved defenses against parasites:
• skin, tears, saliva, mucus, ….
Parasites have evolved ways to compensate:
• tegument, anticoagulants, anesthetics, ….
What type of symbiosis?
Examine the following slides….is it?
Mutualism
Commensalism
Parasitism
Acacia Plant
and Ants
• Ants protect
acacia from
grazing
herbivores
• Acacia provides
ants with a place
to live and nectar
at the base of leaf
stalks
Moray Eel with
Cleaner Shrimp
• Moray Eel gets….
a clean mouth
• Cleaner Fish gets….
a meal
Flower and Bumble Bee
• Flower gets
pollinated
by the bee
• Bee gets
nectar and
pollen from
the flower
Silverfish and
Army Ants
some species of silverfish inhabit the nests of
army ants and live by scavenging on the refuse
of their hosts, but without affecting the ants
Cape Buffalo with Egrets
• Cattle stir up
insects as they
eat grass and
move around
• Egrets hang
around and eat
insects from
cattle and
surroundings
Tapeworm and Human
• Worm infects the human body…..
Lichen : Fungus and Alga
• Fungi support and
protect the algae,
allowing it to live
in areas usually
unsuitable to the
algae
• Algae provide
food through the
process of
photosynthesis
Birds Nesting in a Tree
Vampire Finch and Other Birds
The vampire finch supplements
it s diet by feeding on the blood
of other birds by pecking at the
skin until they draw blood
Clown Fish with Anemone
Clown fish gets
protection
from it
predators
Sea Anemone
gets ?
What symbioses is this?
What symbioses is this?
Heart Worms
What symbioses is this?
Embedded Tunga fleas
What symbioses is this?
What symbioses is this?
How Living Things Meet
Their Energy Needs
The energy source for most living things is….
AUTOTROPHS (producers) – can
produce their own food and
meet their own energy needs
auto = “self”
troph = “feeder”
Autotrophs can be ….
photoautotrophs or chemoautotrophs
Photoautotrophs (plants, algae, some bacteria)
perform….Photosynthesis – which uses light
energy to produce carbohydrates /food/fuel
Chemoautotrophs (some bacteria) perform….
Chemosynthesis – uses chemical energy to
produce carbohydrates/food/fuel
Plant Responses (Tropisms)
Photo-tropism =
response toward light
Geo/Gravitropism =
response toward
gravity
Thigmo-tropism =
response to pressure
or touch
HETEROTROPHS (consumers)…
cannot produce their food and
must consume other living things
hetero = “other”
troph = “feeder”
Many kinds of heterotrophs ….
Herbi-vores – feed on plants
Carni-vores – feed on animals
Omni-vores – feed on plants and animals
Detriti-vores – feed on detritus (dead organic matter)
includes…worms, beetles
Decomposers – break down organic matter and
recycle nutrients - includes…bacteria and fungi
Energy Flow through an Ecosystem
THE SUN
producers
consumers
energy flows in ONE DIRECTION in an
ecosystem – from producers to consumers
Food Chain
a series of steps
in which
organisms
transfer
energy by
eating and
being eaten
Food Web
the interrelated
food chains
within an
ecosystem
TROPHIC LEVEL
(“feeding” level)
each step in a food chain or food web is
called a trophic level
a trophic level indicates an organism’s
position in the sequence of energy
transfers
most ecosystems have only 3 or 4 trophic
levels
Is this a food chain
or a food web?
How many
trophic levels
are in
the diagram?
• producers – Make food
• primary (1st order) consumers – Eat producers
• secondary (2nd order) consumers – Eat producers
and primary consumers
• tertiary (3rd order) consumers – Eat producers,
primary, and secondary consumers
• quaternary (4th order) consumers –Eat
producers, primary, secondary, and tertiary
consumers
Trophic levels can be represented with an
ECOLOGICAL PYRAMID which shows the
relative amounts of MATTER AND ENERGY
contained within each level
Ecological Pyramids
used to represent the relative amounts of
energy or matter contained within each
trophic level
ENERGY PYRAMID
BIOMASS PYRAMID
PYRAMID OF NUMBERS
Energy Pyramid
• shows the relative amount of energy available
at each trophic level
• only about 10 % of the energy available at
each level is transferred to the next
• about 90% of the energy at each level is lost
as heat or is used in life processes ….
–such as digestion, running, eating, respiration,
maintaining temperature, sleeping,….
Biomass Pyramid
represents the amount of biomass (living
organic matter) at each trophic level
represents the amount of potential food
available for each trophic level
typically, the greatest biomass is at the bottom
of the pyramid
Pyramid of Numbers
represents the relative
number of individual
organisms at each
trophic level
Bio-geo-chemical Cycle
(life-earth-chemical cycle)
elements, chemical compounds and other forms of
matter MUST BE RECYCLED and are passed from one
organism to another and from one part of the biosphere
to another through a bio-geo-chemical cycle
The Water Cycle
(also called the hydrologic cycle)
movement of water between the ocean,
atmosphere, land (GEO) and living things (BIO)
Evaporation – water changes from liquid to gas
Transpiration – water loss (evaporation) from plants
Perspiration – water loss (evaporation) from animals
Condensation – formation of liquid water from water vapor
Precipitation – water returns to Earth’s surface as
rain, snow, sleet or hail
IMPORTANCE OF WATER…
Carbon(& Oxygen) Cycle
cycling of C and O between the various components of the
biosphere – organisms, air, water, land,…(BIO-GEO)
Important processes in this cycle….
• Decomposition • Combustion • (Cellular) Respiration • Photosynthesis Importance of carbon and oxygen - key ingredient in all living
things C, H, O, N
Nitrogen Cycle
cycling of N between living things (BIO) and
atmosphere, land, water (GEO)
Nitrogen Fixation – conversion of nitrogen gas into ammonia
performed by some bacteria
Denitrification – conversion of nitrates into nitrogen gas
performed by some bacteria
Assimilation – to incorporate (N or other substances)
into cells and tissues
all organisms require N to make amino acids which
in turn are used to make proteins (in protein synthesis)
Phosphorus Cycle
cycling of P between living organism (BIO) and
rocks, soil and ocean sediments (GEO)
unlike water, carbon, oxygen and nitrogen - phosphorus
does not usually enter the atmosphere
phosphorus is essential to living things because it is
an important component of DNA and RNA
Important processes in this cycle…
Leaching, Mining, Erosion, Weathering
(Biological) Community…
• all living things in the same area at same time
Communities
Limiting Factor - biotic or abiotic factor that
restricts the numbers, reproduction, or
distribution of an organism
Examples of limiting factors…
food, water, habitat, disease, fire and other
natural disasters,….
Ecological Succession
changes in a community over time
• occurs when a new land area is exposed
or when an existing land area is disturbed
Ecological Succession
Pioneer Community – first community
Seral Community(ies) – intermediate communities
Climax Community – final community that reestablishes itself
The climax community
of North Georgia
is a deciduous forest.
The climax community
of southern Arizona
is a desert.
Primary Succession
occurs on new land areas or areas where no soil exists
(soil formation must occur)
EXAMPLES - volcanic islands, bare rock, glacier melting,…
Pioneer Species
• the first species to inhabit an area
• mosses + lichens
• What is a lichen?
Secondary Succession
occurs when an existing community had been disturbed
Latitude affects climate…
Latitude = distance (N or S) from the equator
• low latitudes (near the equator) receive direct sunlight
• high latitudes (near the poles) receive indirect sunlight
Climate = average conditions of temperature and precipitation in an area
• is most affected by the angle of sunlight (DUE TO LATITUDE)
CLIMATE
average conditions
of temperature
and precipitation
in a particular region
What is our climate?
What is Alaska’s climate?
WEATHER
day to day conditions of the
Earth’s atmosphere at a
particular time and place
What was the weather on
Thanksgiving Day?
Greenhouse Effect
• natural phenomenon
• heat is retained (TRAPPED) by
greenhouse gases in the atmosphere
• keeps the planet warm
• makes life on Earth possible
Some scientists believe that an …..
ENHANCED GREENHOUSE EFFECT is
causing GLOBAL WARMING; other disagree
In summary…
Latitude  determines climate
Climate  determines weather
Weather  determines precipitation
Precipitation  determines flora (plant life)
Flora determines fauna (animal life)
BIOME
large geographical area having…
characteristic temperature range and precipitation
characteristic plants and animals
TERRESTRIAL (land) BIOMES
TUNDRA
TAIGA or BOREAL FOREST or CONIFEROUS FOREST
TEMPERATE DECIDUOUS FOREST
TEMPERATE RAIN FOREST
TEMPERATE GRASSLAND
TROPICAL GRASSLAND OR TROPICAL SAVANNA
DESERT – hot or cold
TROPICAL RAIN FOREST
Tundra
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Cold & treeless
Covers 1/5 of world’s land
Little precipitation (mostly frozen)
Flora: Small, slow growing plants (grass, moss, sedge)
Permafrost: permanently frozen soil under surface
Summer: boggy ponds (because of melting snow and
ice & different fauna
Fauna…caribou, arctic
fox, snowy owl, musk ox
Tundra
Taiga (or Boreal Forest or
Coniferous Forest)
• south of the tundra; in the N hemisphere
• Flora: cone-bearing, evergreen trees - CONIFERS
(pines, hemlocks, spruces, junipers, firs)
Fauna…moose,
grizzly bear, wolf
Taiga (or Boreal Forest or Coniferous Forest)
Temperate Deciduous Forest
Temperate Deciduous Forest
• Trees that lose their leaves are found here =
deciduous trees
• Warmer winter, longer summers = temperate
• Flora: birch, oak, maple, beech, dogwood, &
some evergreens
*you live in this biome
Fauna… fox, squirrel, WT deer,
raccoon, black bear, coyote
Temperate Deciduous Forest
Temperate Grassland
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Also known as prairies (“the bread basket”)
Dominated by grasses
Less rainfall, so not too many tall trees
Rich, fertile soil
Flora: corn, wheat, potatoes, many other cereal grains
Fauna… coyote,
gopher, bison,
antelope
Temperate Grassland
Tropical
Grassland
AKA
Tropical
Savanna
Tropical Grassland
• can be in tropical or subtropical regions
• Flora: Mainly grasslands with scattered trees & shrubs
Fauna…
lots of herbivores (zebra, giraffe, gazelle)
as well as carnivores (lions, leopards, cheetahs)
Tropical Grassland
Desert
can be hot or cold;
we will focus on hot deserts
• Less than 10 inches (25 cm) rainfall per year
• Can be cold because of the low humidity (moisture)
• Sparse vegetation that have adaptations for the dry conditions
– waxy coating, water storage, transpire @ night, thorns on
exterior for protection
• Flora: cacti, Joshua trees, creosote,…
Fauna… kit foxes, snakes,
lizards, road runners,…
Deserts
Tropical Rainforest
most productive biome –
GREATEST BIODIVERSITY
BIODIVERSITY = the variety of
living things in an area
3 kinds of biodiversity
species, ecosystem, genetic
• most of world’s species live here
• warm year round
• little variation in temperature
Tropical Rainforest
• Canopy - formed from a
continuous layer of treetops
that shades the forest floor
• Precipitation: 100 + inches per
year; rains almost daily
• Flora: lilies, orchids, vines,
broad-leaved trees, ferns,…
• Fauna: sloth, birds, monkeys,
beetles, butterflies…
scarlet macaw
marmoset
Tropical Rain Forests
Aquatic/Water Ecosystems
are determined by water chemistry (pH, salinity, dissolved
oxygen,…) depth, flow and temperature
Aquatic Ecosystems
SALTWATER
- includes marine areas and salt lakes
- these areas contain a higher percentage of dissolved salt
Marine areas include…oceans, coral reefs, bays, gulfs, seas
• these areas make up 97.5% of water on Earth
Aquatic Ecosystems
FRESHWATER AQUATIC ECOSYSTEMS
- contain little dissolved salt
- Include rivers, streams, lakes, ponds,…
- make up only 2.5% of water on Earth
- most freshwater is “tied up” in glaciers and polar ice caps
GROUNDWATER…
water found under ground
There are transitional aquatic
ecosystems where saltwater and
freshwater merge….
wetlands and estuaries
Estuary - wetlands formed where rivers
(fresh water) meet salt water
• these areas are
affected by the
rise and fall of
tides
• are usually shallow
• serve as spawning
and nurseries
for many aquatic
species
Population Density
The number of individuals in a given area
Factors that may affect
population density….
Density independent factor – affects a
population regardless of the density of the
population – usually abiotic; weather
events…
examples
Density dependent factor – affects a population
on the basis of the number of organisms –
predation, competition, parasitism, disease,…
More population density factors…
• Immigration – movement of individuals
into an area
• Emigration – movement of individuals
out of an area
Carrying Capacity – the number of
individuals that can be supported by a
given area (even a grocery bag has a carrying capacity)
Human population growth is
causing…
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severe overcrowding in areas
An increase in energy demands
A need for increased food supply and waste disposal
very rapid ecological change (habitat destruction,
overhunting, introduction of diseases)
* The population tripled from 1930-2000 and is
expected to double again from 2000-2050