Download B 6 Ecology and Conservation

Ecology and Conservation
TSWBAT: Demonstrate an
understanding of the interrelationships
between organisms, their environment,
and man.
Ecosystem
• A community of
interacting
organisms and the
abiotic factors that
affect them
– Community = all
living organisms in
a given area
• Plants, animals, etc.
Abiotic Factors
• Nonliving
characteristics of
an ecosystem
– Weather,
temperature,
rock/soil chemistry,
rainfall
• Influence the
existence of the
living organisms
Biotic Factors
• Living organisms that
share the same
ecosystem
– will interact with each
other, directly or
indirectly.
• They will form different
types of relationships
• Predator-Prey Relationships
– One species (the predator) eats another species
(the prey)
• If # prey increases, the # of predators increases
• If # prey decreases, the # of predators decreases
Competition
• 2 or more organisms
need the same resource
at the same time.
• Within the same-species or
between different species
• The organisms typically
occupy the same niche
• Niche = the role of an
organism within its habitat
• Symbiosis
– Species have coevolved
Organism 1
Organism 2
Mutualism
Benefits
Benefits
Commensalism
Benefits
Parasitism
Benefits
Neither
benefits, nor
is Harmed
Harmed
Example
Stable Ecosystems
• Stable = Healthy
– The # of organisms fluctuates predictably
– The amount of resources fluctuates
predictably
– Energy flow through the system is unchanging
• Healthy ecosystems are productive
Energy in Living Systems
Biosphere
• Part of the Earth that supports LIFE
Life Requires Energy
• Source of energy for life on Earth = Sun
– The sun’s energy enters Earth’s ecosystems
through photosynthetic organisms
• Trees, plants, algae
• Autotrophs
– Photosynthetic
organisms
– Use sunlight to make
food
• Heterotrophs
– Eat other organisms
for food
• Producers
– Trees, plants, algae
• Primary Consumers
– Herbivores
• Secondary
Consumers
– Omnivores
– Carnivores
– Detritivores
Flow of Energy Models
• Diagrams are used to show the direction
energy goes between organisms
– Food Chain: unidirectional
– Food Web: multidirectional
– Energy Pyramid: shows relative quantities
• Though it may not always be included, for every
food chain, food web, or pyramid, the SUN is the
originating source of all energy
Food Chain
Food Web
Energy Pyramid
Secondary Consumers
(least amount)
Primary Consumers
Producers
(greatest amount)
Life Is Always Changing
• Organisms compete for energy
– Plants try to “outgrow,” other plants
• Succession is the process environments
undergo as plants compete with each
other for resources
– Sunlight, soil nutrients, water, space
Primary Succession
• Bare rock is sloooooowly converted to soil
– Soil is: absent, only rocky ground
– Producers are: lichens & mosses
• Pioneer species
– Endemic Animals are: few, if any
• Most are transient
Secondary Succession
• Green plants replace lichens; compete
with each other
– Soil is: present
– Producers are: grasses, shrubs, fast-growing
trees
– Endemic Animals are: mostly small
– Birds, mice, rats, lizards, snakes
• Some larger species may visit
– Deer, coyotes, wolverines
Climax Community
• Mature forest; changes little over time
– Soil is: present, quality varies
– Producers are: Large trees, few shrubs,
mosses
– Endemic Animals are: varied
– Complex food webs are present
Primary Succession
Secondary Succession
Mature Forest
• Succession can also occur if part of a
forest is disturbed
– A tree falls, forest fire, land slide, logging
• Plants immediately begin to compete to be
the ones to get all the sun
Biogeochemical Cycles
Cycling of Matter
• Living organisms need specific nutrients to
survive.
– These nutrients can be found in
•
•
•
•
Food
Water
Rocks & Soil
Air
• All necessary nutrients are recycled in the
biosphere.
• 4 common biogeochemical cycles are:
– Hydrologic cycle (water cycle)
– Carbon cycle
– Nitrogen cycle
– Phosphorous cycle
Water Cycle
•
Life needs water
1. Sky to Earth’s surface
– Condensation: Cold temp. changes water vapor to a liquid
– Precipitation: liquid water falls to the Earth
2. Earth’s surface to Sky
– Transpiration: plants release water vapor as a product of
photosynthesis
3. Earth’s surface to oceans
– Percolation: water filters through soil
4. Oceans to Sky
– Evaporation: Heat changes liquid water to a gas
Carbon Cycle
• Life needs Carbon
– Used to make carbohydrates & lipids
1. Sky to Producer
– Plants use CO2 gas to make glucose (C6H12O6)
2. Producer to Consumer
– Consumers receive carbon by eating producers
3. Consumer to Sky
– Exhale CO2 gas
4. Producer & Consumer to soil
– Dead organisms are converted to fossil fuels
5. Soil to Sky
– Burning fossil fuels releases CO2
Nitrogen Cycle
•
Life needs Nitrogen
– Used to make proteins & nucleic acids
1. Sky to Producer
– Lightning
– Bacteria in soil convert unusable nitrogen from the air to a usable form
2. Producer to Consumer
– Consumer received nitrogen by eating a producer
3. Consumer to soil
– Consumer’s wastes contain nitrogen
4. Soil to Sky
– Bacteria convert waste to nitrogen gas
Phosphorous Cycle
• Life needs Phosphorous
– Used to make cell structures, energy (ATP)
1. Earth’s Surface to Lakes & Oceans
– Mountain rock containing phosphorous is eroded by rain water
– Fertilizer runoff ends up in lakes & oceans
2. Lakes/ponds to Producers
– Producers absorb phosphorous through roots
3. Producers to Consumers
– Consumer’s eat producers
4. Runoff, Producer & Consumer to Soil
– Eroded rock, waste & dead organisms decay to form sediment
5. Soil to Mountains
– Sedimentary rock is thrusted upward to form mountains
Community Ecology
Community Ecology
• Ecosystems are
made up of many
different, interacting
populations of
organisms, and the
abiotic factors that
affect them
– Plants & animals
– Water, temperature
Biomes
• Large groups of ecosystems that share the
same climate & have similar plants
– Affected by annual rain fall, sunlight levels &
temperature
• Terrestrial Biomes
– Jungles, deserts, tundra, grasslands
• Aquatic Biomes
– Rivers, ponds, lakes, oceans
Community
• Groups of interacting
populations of
different species
found in the same
area at the same time
Population
• A group of individuals
of the same species
found in a specific
area.
Habitat
• Where a single organism, or a population of
organisms lives.
– Can be small: under a rock, in a tree
– Can be large: a forest, an ocean
Limiting Factors
• Limiting factors are
types of biotic &
abiotic factors that
control the size of a
population.
Density-Independent Factors
• Limiting factors that affect a population,
irregardless of the size of the population
– Temperature, space, nutrient availability
– Natural disasters; fire, volcanic eruptions, tsunamis,
drought
• Example: Fish: water salinity (saltiness)
– Too salty, can’t survive
– Not salty enough, can’t survive
Density-Dependent Factors
• Limiting factors that affect a population,
depending on the size of the population
– Competition, disease, starvation, predation,
• Example: White-tail Deer Vs. Wolves
– Too many wolves, all the deer are killed
– Too few wolves, the deer eat all their resources and
starve
Range of Tolerance
• Limiting factors can vary between upper &
lower extremes
– What an organism can survive = tolerance
• Organisms exist in the range between the
two extremes
End Ecology Unit
Start Population Unit
Chs 4 & 5
Population Density
• The number of individual organisms in a
specific area
Spatial Distribution
• How far apart organisms are from each
other in an area.
Wolves in Michigan
Limiting Factors
• Density-Independent Factors
– Factors that impact organisms, no matter how
many organisms exist in an area
– Usually Abiotic
• Density-Dependent factors
– Factors that impact organisms depending on
how many organisms exist in an area
– Usually Biotic
Population Change
• To increase a population:
– Increase # of births
– Increase survival, decrease # deaths
– Increase the # that immigrate
• To decrease a population:
– decrease # of births
– decrease survival, increase # deaths
– Increase the # that emigrate
Reproductive Patterns
• r-strategist species
– Mature quickly
– Produce many offspring
– Offspring are precocial-require less parent care
• k-strategist species
– Mature slowly
– Produce less offspring
– Offspring are altricial-require more parent care
Population Growth Patterns
• Exponential Growth
– Population increases
slowly at first
• lag phase
– Population explodes
and increases rapidly
– If population
surpasses carrying
capacity, could crash
• Logistic Growth
– Growth is slow at first
– Then growth speeds
up
– Then growth slows as
it approaches the
carrying capacity of
the environment
Carrying Capacity
Human Population
• Globally, the human population is
exponentially growing
– Positive Growth = # births or immigrants is
greater than # deaths or emigrants
– Zero Growth = # births or immigrants is equal
to # deaths or emigrants
– Negative Growth = # births or immigrants is
less than # deaths or emigrants
Demography
• The study of human population size,
density, distribution, movement, and
birth and death rates.
– Demographers use age structure charts to
study population changes in countries around
the world
Age Structure Charts
• Divide human populations into 3 groups:
– 1: Pre-reproductive: 0-19yrs
• Not usually contributing to growth, but will
– 2: Reproductive: 20-44yrs
• Currently contributing to growth
– 3: Post-Reproductive: 45-80+yrs
• Will no longer contribute to growth
• Each country’s population changes,
depending on the resources available in
that country.
Density-Dependent Factors
• Increasing the number of people in an
area, but not increasing the area leads to
stress.
– Stress is a physical and emotional reaction to
unfavorable environmental conditions.
• Stress can lead to emigration, disease outbreaks,
or war and other antisocial behaviors.
Density-Dependent Factors
• Disease:
– disease outbreaks are more likely to occur
when human-to-human contact increases.
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Bubonic plague
Small pox
Influenza
Ebola
Cholera-current problem in Haiti
Biodiversity &
Conservation
Biodiversity
• The variety of species of plants and other
organisms in a specific area
– More variety = increased biodiversity
Biodiversity Contributes to…
• Stable Ecosystems:
– Different species may share the same niche,
thus no 1 species is solely responsible for a
specific purpose.
• If that species no longer thrives, other species can
replace it’s function
• Genetic Diversity:
– # of genes & alleles affects species survival &
development
• Having a greater variety of genes ensures that
organisms will have a greater ability to survive
ecosystem changes
Natural Resource Usage
• Renewable Resources
– Organisms, or products of organisms, that
can be replaced as fast as they are used.
• Bamboo, r-strategist species (rabbits, mice)
• Nonrenewable Resources
– Organisms, or products of organisms, that
can not be replaced as fast as they are used.
– Will run out if we do not change how we use
them.
• Fossil fuels, k-strategist species (Panda, Leopard)
Biodiversity & Medicine
• Scientists continue to
find new medicines
from plants and other
organisms that are
used in the treatment
of human diseases.
Anti-Tuberculosis
Loss of Biodiversity
• Weakens
Ecosystems:
– Ecosystems become
dependent on just a
few species.
– If these species are
lost, then the entire
ecosystem could be
lost.
Without Biodiversity
• Our water will become dirtier
– No fishing, no swimming
• Our forests will become smaller
– no wood, no paper
• Our parks will become quieter
– No birds
• Our world will become emptier
Threats to Biodiversity
• How to lose an Ecosystem:
– Poorly controlled use of natural resources
– Overdevelopment of land
– Over hunting of animals
– Pollution
– Natural Disasters
Pollution & Conservation
Pollution
• Non-natural chemicals that damage
natural biogeochemical cycles
– Can sicken or kill living species
– Can degrade abiotic factors
Common Pollutants
• Sewage, fertilizers, pesticides, industrial
waste
– Rich in phosphorous & nitrogen
– May contain mutagens or carcinogens
• Gases produced from burning fossil fuels
– Sulfur dioxide, nitrogen oxides, carbon
monoxide, CFCs
• Litter
Acid Rain
• Sulfur & Nitrogen gases are released by
burning fossil fuels
– These gases combine with water in the
atmosphere and form nitric acid and sulfuric
acid
– These acids precipitate towards Earth,
damaging plants, and water bodies
Eutrophication
• Excess phosphorous & nitrogen from
farm runoff & sewage enter the waterways
• Causes algae to multiply.
– The algae use up the oxygen in the water for
cellular respiration.
– Other oxygen-dependent organisms suffocate
A
Manitoba, Canada
Picture A: Circa 1975
B
Picture B: Circa 1994
After nearly 19 yrs of
phosphorous
pollution.
Biological Magnification
• Pollutants and toxins
become more
concentrated, further
up a food pyramid
– Producers receive the
least amount of poison
– Top consumers
receive the most
amount of poison
Conservation Efforts
• Reduce, Reuse, Recycle
– Best way to prevent waste from entering an
ecosystem is by not making any to begin with.
• Clean Ups
– Global efforts to fix polluted areas
– Super Fund: US $ set aside for cleaning
polluted areas
• Laws
– Environmental Protection Agency
Bioremediation
• Use of living
organisms, such as
bacteria, fungi, or
plants, to detoxify a
polluted area.
Biological Augmentation
• Sometimes, species from other countries
enter the US, and out-compete local
species for resources.
• Predators of these nonnative species are
then introduced in order to remove the
damaging species, and return balance to
our native ecosystems
Responsible Stewardship
• People are going to use natural resources.
• If these resources are used wisely, then
they can last a very long time and without
polluting.
• We ALL need to work together to make
sure future generations have a healthy
planet.