Notes: Biology I S409

1

• Notes Biology I S409 Ecology Unit
• Chapter 2 Principles of Ecology
• 2.1 Organisms Their Relationships
• 2.2 Flow of Energy in an Ecosystem
• 2.3 Cycling of Matter
• Chapter 5 Biodiversity Conservation
• 5.3 Conserving Biodiversity

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2.1 Organisms Their Relationships

• definition the scientific discipline in
  which the relationships among living organisms
  and the interaction the organism have with their
  environments are studied.
• The study of organisms interacting with each
  other the environment

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The Biosphere
T 2, 9

• Biosphere the portion of the Earth that
  supports life (polar, desert, ocean
  rainforest)
• Biotic Factors factors in an organisms
  environment
• The biological influences on organisms within an
  ecosystem
• Examples animals, plants, mushrooms bacteria
• Abiotic Factors factors in an organisms
  environment
• Physical, or nonliving, factors that shape
  ecosystems
• Examples temperature, air/water current,
  sunlight, precipitation, humidity, soil nutrients

4
Understanding Communities
T 1

• Keys to understanding biological communities is
  to be aware of latitude and climatic conditions
• - the average conditions in a region
• Temperature - of hours/intensity of sunlight
• Precipitation - amount of moisture
• Topography shape elevation of landmasses
  (mountain affect)
• the condition of the atmosphere at a
  specific place and time

5
Levels of Organization
T 2

• Ecologists that occur between the levels of
  organization
• Organism one individual living thing
• Species organism that produces offspring
• Population several of same species in one place
• Community populations interacting different
  species
• Ecosystem communities interacting w/ environment
  
• Biome large geographic area different
  ecosystems w/ similar climate and communities
• Biosphere combines all parts of the planet
  land, water, air that support life
• The portion of the planet that supports life

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Levels of Organization
T 2
7
Ecosystem Interactions
T 1, 10

• Habitat an area where an organism lives
• Niche role or position that an organism has in
  its environment
• Community Interactions
• Competition organisms of the same or different
  species attempt to use the same ecological
  resource in the same place at the same time.
• Predation interaction in which one organism
  captures (predator) and feeds on another
  organism (prey)

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Symbiotic Relationships
T 10, 11

• Symbiosis a close relationship between 2 species
  
• Mutualism both species benefit from the
  relationship Ex bees flowers
• Commensalism one member of the association
  benefits and the other is neither helped nor
  harmed Ex shark remora fish
• Parasitism one organism lives on or inside
  another organism and harms it. The parasite
  obtains all or part of its nutritional needs from
  the other organism, called the host. Ex
  hookworm, tick

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2.2 Flow of Energy in an Ecosystem
T 1

• All living things require energy where does it
  come from?
• Originally the sun
• Stored form chemical bonds
• Organisms differ in how they obtain their energy
  
• troph an organism that makes its own food
• troph an organism that gets its energy by
  consuming other organisms

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Energy in an Ecosystem
T 1, 5

• Autotrophs Capture energy from the environment
  to make/produce own food
• AKA (Example Green Plants)
• Two ways to produce own food
• Using the sun Photosynthesis
• Using inorganic chemicals Chemosynthesis
• NO sun
• Ex Hydrogen Sulfide

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Energy in an Ecosystem
T 1, 4

• Heterotrophs rely on other organisms for food
• AKA consumers can NOT make own food
• Herbivores
• Eat plants only Cow 1st order consumer
• Carnivores
• Eat animals only Snake 2nd order consumer (or
  3rd?)
• Omnivores
• Eat both plants animals Bear 3rd order
  consumers
• Detritivores
• Engulf dead plant animals Worm, snail, mite
• Decomposers
• Absorb nutrients from dead organisms Fungus
  (mushroom), bacteria

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Concept Check

• No matter how complicated a food web can get,
  what is the original source of energy?
• What are two new names for plants?
• What are two names for organisms that can NOT
  make their own food?

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Models of Energy Flow
T 6

• Energy passes from source to organism to organism
  to organism etc.
• This sequence is called a Food Chain
• Sun, wheat, mouse, snake, hawk
• Each link in a food chain (which is a transfer of
  energy) is called a Trophic Level
• First trophic level is always a producer
• 1st, 2nd, 3rd, 4th trophic levels are consumers
• When Food Chains cross or interact it becomes a
• Food Web a model of the relationships that form
  a network of interactions (producer to decomposer)

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Models of Energy Flow
T 6
15
Food Web Examples
T 6
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Ecological Pyramids
T 7

• Ecological Pyramids diagrams relationships (3
  types)
• Pyramid of Energy each level represents the
  amount of energy available to that trophic level
• Only 10 of energy can be passed less energy
  available at each successive level or with each
  step up, there is an energy loss of 90
• Pyramid of Biomass total amount of living tissue
  w/in a given trophic level biomass decreases at
  each successive level or each level represents
  the amount of biomass consumed by the level above
  it
• Pyramid of Numbers diagrams of individuals in
  each level s decrease at each successive level

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2.3 Cycling of Matter
T 8

• Energy flow is matter is NOT used up!
• Matter can be through ecosystems
• Important Biogeochemical Cycles
• Water repeated movement of water b/w Earths
  surface the atmosphere
• Carbon Oxygen photosynthesis, burning of
  fossil fuels, decomposition of plants animals
• Nitrogen soil nitrogen fixed by bacteria for use
  by organisms atmosphere is 80 nitrogen
• Phosphorus cycles among the land, ocean
  sediments, and living organisms

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3 Main Ways to Study Ecology
T 3

• Asking questions
• Making hypotheses
• Usually leads to experimenting modeling
• Test hypotheses
• Set up in a lab or in the field
• Used when time /or size is too large
• Mathematical formulas based on above used to
  make predictions, which are further tested

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Concept Check

• What is ecology?
• What is the most simple group of more than one
  kind of organism in our biosphere?
• What are 3 methods ecologists use to study the
  living world?

20

• Notes Biology I S409 Ecology Unit
• Chapter 5 Biodiversity Conservation
• 5.3 Conserving Biodiversity

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5.3 Natural Resources

• The biosphere currently supplies the basic needs
  for more than 6 billion humans in the form of
  natural resources
• The consumption rate of natural resources is
  evenly distributed
• The natural resource consumption rate is much
  higher for people living in developed countries
  than for those people in developing countries
• Because of the rising human population growth
  and an increased rate of consumption of natural
  resources a long-term plan for the use and
  conservation of natural resources is important

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Human Impact
T 12

• Human activities - most important source for
  environmental change on Earth that affect the
  Biosphere
• Hunting Gathering food sport
• Subsistence Hunting (hunt for food)
• Agriculture farming plants animals
• Monoculture one type of crop in an area
• Green Revolution use of chemical fertilizers
• Problems w/ pesticides (water) and resistance ?
• Urban Development
• Use of fossil fuel for energy
• Production of waste

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Renewable vs. Nonrenewable Resources

• Renewable resources those resources that are
  replaced by natural processes faster than they
  are consumed
• can regenerate if they are alive
• can be replenished by biochemical cycles if
  nonliving
• Ex Agriculture, Animals, Trees, Water, Solar
  energy
• NOTE A resource may be destroyed or polluted and
  will no longer be useable!! A renewable resource
  is not necessarily unlimited!
• Nonrenewable resources those sources that are
  found on Earth in limited amounts or those that
  are replaced by natural processes over extremely
  long periods of time
• Ex fossil fuels, mineral deposits, coal, oil,
  natural gas and an extinct species (or cleared
  forests?) ?

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T 14
Use of Natural Resources

• Sustainable use using natural resources at a
  rate in which they can be replaced or recycled
  while preserving the long-term environmental
  health of the biosphere
• Conservation of resources include
• Reducing the amount of resources that are
  consumed
• Recycling resources that can be recycled
• Preserving ecosystems
• Using the ecosystem in a responsible manner
• Ex Forest Management, Aquacultures
• Pollutant a harmful material that can enter the
  biosphere through the land, air, or water
• The contamination of air, water, or soil by
  materials released into the environment through
  human activities.

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Comprehension Check

• Can you name one type of renewable resource?
• Can you name one type of nonrenewable resource?
• What effects do sustainable-use have on the
  environment?

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ProtectingBiodiversity

• Protected areas in the US
• 1st National Park Yellowstone National Park
  (1872)
• Since, added many national parks and nature
  reserves
• International protected areas
• 7 of the worlds land is in some type of reserve
• The United Nations supports Biosphere Reserves
  and World Heritage Sites
• This includes megareserves which have habitat
  areas that are protected from human activity by
  buffer zones which sustainable use of natural
  resources is permitted

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T 13
ProtectingBiodiversity

• Biodiversity Hot Spots An area where there are
  high levels of endemic species (a species only
  found in one specific location)
• There must be at least 1500 species of vascular
  plants that are endemic
• The region must have lost at least 70 of its
  original habitat
• Currently 34 hot spots on the Earth.

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Corridors between habitat fragments

• Corridors passageways between habitat fragments
• Positives
• All organisms from one area to move safely to the
  other
• Creates a larger piece of land that can sustain a
  wider variety of species and a wider variety of
  genetic variation
• Negatives
• Disease can also easily pass
• Increases edge effect

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RestoringEcosystems
T 15

• Sometimes biodiversity is destroyed in an area
  such that is no longer provides the abiotic and
  biotic factors needed for a healthy ecosystem
• Cleared rainforest, mining, oil spill
• Bioremediation- use of living organisms to
  detoxify a polluted area (microorganisms in soil
  to break down toxins)
• Biological Augmentation- adding natural predators
  to a degraded ecosystem (introducing ladybugs to
  eat aphids which destroy crops)

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Legally Protecting Biodiversity

• The 1970s there was a lot of attention given to
  issues surrounding the environment
• 1973 The US enacted the Endangered Species Act
• 1975 International Treaty formed CITES
• The Convention on International Trade in
  Endangered Species of Wild Fauna and Flora

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Comprehension Check

• What makes something a Biodiversity Hotspot?
• How many Hotspots currently exist on Earth?
• What are some things that can be done to protect
  biodiversity?