Chapter 3: Ecosystems and Energy Master Presentation

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Chapter 3 Ecosystems and Energy Master
Presentation
The coral reef community can teach us a lot about
how energy flows through an ecosystem. Corals
have the most species of all aquatic ecosystems
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Overview of Chapter 3

• What is Ecology?
• The Energy of Life
• Laws of Thermodynamics
• Photosynthesis and Cellular Respiration
• Flow of Energy Through Ecosystems
• Producers, Consumers Decomposers
• Ecological Pyramid
• Ecosystem Productivity

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Ecology

• Ecology
• eco house logy study of
• The study of interactions among and between
  organisms in their abiotic environment
• Biotic - living environment
• Includes all organisms
• Abiotic - non living or physical environment
• Includes living space, sunlight, soil,
  precipitation, etc.

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Ecological Levels

• The Earths biosphere (living realm) includes
  many sub-categories. Some of these are
• Organisms and species
• Ecosystems
• Communities
• Cells
• Atoms
• Populations
• Also.the biosphere is constantly interacting
  with the physical components of the lithosphere,
  hydrosphere, and atmosphere

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Lets see if you can organize yourselves into a
logical order.

1. Each person takes a term, and then compares it to
   all others.
2. Organize the class from smallest concept to
   largest
3. Decide what terms are part of the study of
   Ecology
4. Complete the matching activity

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Ecology Definitions

• Species
• A group of similar organisms whose members freely
  interbreed
• Population
• A group of organisms of the same species that
  occupy that live in the same area at the same
  time
• Community
• Al the populations of different species that live
  and interact in the same area at the same time
• Ecosystem
• A community and its physical (abiotic)
  environment
• Landscape
• Several interacting ecosystems

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Ecology

• Ecologists are interested in the levels of life
  above that of organism

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Ecology

• Biosphere contains earths communities,
  ecosystems and landscapes, and includes

• Atmosphere - gaseous envelope surrounding earth
• Hydrosphere - earths supply of water
• Lithosphere - soil and rock of the earths crust

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The Chesapeake Bay ecosystem

• The Chesapeake Bay is a special place!
• It is an estuary just like the lower to mid
  Hudson! It is under the influence of tides!
• It represents a subtle shift from salt water to
  brackish water to fresh water, which changes with
  the tides and changes with precipitation levels.
• It contains salt marsh aquatic communities with
  surrounding meadow, wetlands, and forested areas
  (also similar to the Hudson)
• It provides ecologists with a great case study to
  examine multiple interactions among organisms and
  between the organisms, the ecosystem, and of
  course..
• HUMANS!

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A typical Chesapeake Bay food web..See how all
the organisms interact with one another and with
the physical surroundings and components of air,
water, and land?????
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Chesapeake Bay - plants

• Cordgrass is the dominant plantsuited to salty
  conditions
• Nitrates and phosphates from treated sewage and
  agriculture promote rapid growth of cordgrass and
  algae
• Cordgrass and algae are eaten directly by some
  organisms
• Insects and birds are the dominant animal forms
• Mosquitoes, horseflies, sparrows, gulls, clapper
  rails (birds),

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Chesapeake Bay - animals

• Insects and birds are the dominant animal forms
• Mosquitoes, horseflies, sparrows, gulls, clapper
  rails
• The marsh contains shrimp, lobster, crab,
  barnacles, worms, clams and snails.using the
  cordgrass for cover to hide from predators and to
  reproduce
• Sea trout, Atlantic croaker, striped bass,
  bluefish and many other fish use the marsh as a
  nursery (eels too)

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Chesapeake Bay - animals

• No amphibians due to saltwater, but a few
  reptiles can be foundincluding diamondback
  terrapin sea turtles.
• Water snakes prey on fish other snakes live in
  the surrounding dry areas
• Meadow voles move into and out of the marsh
  constantly (they are excellent swimmers)eating
  insects, leaves, and the cordgrass
• Otherwise, there are millions of microorganisms
  and macroinvertebrates that serve to complete the
  complex, interacting food web of the Chesapeake
  Bay!

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Thermodynamics, Photosynthesis, Cellular
Respiration, and Chemosynthesis

• Ahmad Tipu and Kenny Godwin

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What is Thermodynamics?

• It is the study of energy and its
  transformations.
• Scientists use the word system during
  thermodynamic work refer to a group of atoms,
  molecules, or objects when they are being
  studied.
• Everything that is not involved in the study is
  the surroundings.
• The systems then get broken down into two
  systems, open and closed.

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Closed System

• A closed system is self-contained and isolated.
• Energy is not exchanged between a closed system
  and its surroundings. The thermos bottle is an
  approximation of a closed system.
• Closed systems are rare in nature.

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Open System

• Energy is exchanged between an open system and
  its surroundings.
• Earth is an open system because it receives
  energy from the sun, and this energy eventually
  escapes when it dissipates into space.

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First Law Of Thermodynamics

• An organism may absorb energy from its
  surroundings, or it may give up some energy into
  its surroundings, but the total energy content of
  the organism and its surroundings is always the
  same.
• Energy cannot be created or destroyed, although
  it can change from one form to another.
• The energy in the universe 15 to 20 billion years
  ago is the same amount of energy present today.
• This happens to the energy of any system if the
  surroundings are constant.
• An organism cannot create the energy it requires
  to live, it must capture the energy from the
  environment to use for biological work, this
  requires the transformation of energy from one
  form to another.

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Second Law Of Thermodynamics

• The amount of usable energy available to do work
  in the universe decreases overtime.
• Whenever we transfer energy it is an inefficient
  process and energy is lost as heat.
• No process requiring an energy conversion is ever
  100 efficient because much of the energy is
  dispersed as heat, increasing entropy

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What is Entropy?

• It is the measure of disorder or randomness.
• Organized energy has low entropy.
• Disorganized energy like heat, has high entropy.
• Entropy is continuously increasing in the
  universe in all natural processes.
• Entropy is not reversible.

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Photosynthesis

• Photosynthesis is the process by which light
  energy taken from the sun is converted into
  chemical energy in the form of of glucose.
• In this process carbon dioxide, water, and
  sunlight are taken in and through a series of
  steps glucose is formed with water and oxygen as
  by products.
• Many plants, a few algae, and some bacteria
  perform this process in order to supply
  themselves with a supply of energy to be used as
  needed.

Equation for Photosynthesis
6CO2 12H2O radiant energy (sunlight)
C6H1206 6H2O 6O2
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Cellular Respiration

• In order to release stored chemical energy many
  plants and animals go through through the process
  of aerobic cellular respiration in which
  molecules such as glucose are broken down for
  energy.
• When the glucose is broken down in this process
  energy is released and the glucose is broken down
  into carbon dioxide and water.
• There are some organisms which do not use oxygen
  for cellular respiration and they go through the
  process of anaerobic cellular respiration.

Equation
C6H12O6 6O2 6H2O 6CO2 12H2O
Energy
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Chemosynthesis

• Chemosynthesis is when organisms make organic
  compounds by using energy derived from reactions
  involving inorganic chemicals.
• In nature this most commonly occurs in deep sea
  hydrothermal vents which spew out water heated by
  radioactive rocks in the earth.
• There is no sunlight available so many of the
  organisms cannot perform photosynthesis.
• Bacteria living near these vents possess enzymes
  have enzymes which they use to make the inorganic
  molecule hydrogen sulfide react with oxygen and
  produce water, sulfur, or sulfate
• These reactions produce energy for the rest of
  the deep sea ecosystem and allows the rest of the
  creatures to survive in a world without light.

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Deep Sea Vents Video

• http//ocean.si.edu/ocean-videos/hydrothermal-vent
  -creatures -

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Producers, Consumers, and Decomposers

• By Sean Behuniak and Logan Mongelli

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Producers

• Also known as autotrophs(Greek for self
  nourishment) manufacture their energy from simple
  inorganic substances usually CO2 and water,
  generally using the energy of sunlight or better
  known as the process of photosynthesis
• They produce their own food in their bodies
  becoming potential food sources or other
  organisms
• They are the beginning of the food web as well as
  the beginning of the energy flow
• ex. cordgrass,
  algae, photosynthetic bacteria
  

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Consumers

• Also known as Heterotrophs, Consumers use the
  bodies of other organisms as their source of
  food, energy, and bodybuilding materials
• Consumers that eat producers are primary
  consumers or herbivores
• ex. Rabbits and Deer
• ex. Marsh Periwinkle
• -snail that
  feeds on algae in a salt marsh ecosystem
• Secondary Consumers eat primary consumers
• Tertiary Consumers eat secondary consumers
• -Both are
  flesh-eating carnivores that eat other animals
• ex.
  Lions, lizards, spiders
• Omnivores are consumers that eat a variety of
  organisms, both plant and animals
• ex.
  Bears, Pigs and Humans

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Decomposers

• Also called saprotrophs are heterotrophs that
  break down dead organic material and use those
  nutrients to supply their own bodies
• They release CO2 and salts that producers can use
  
• exBacteria,
  Fungi
• These examples clear the way for other
  decomposers such as termites

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More Examples
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Helpful Definitions

• Energy Flow The passage of energy in a one-way
  direction through an ecosystem
• Trophic Level An organisms position in a food
  chain, which is determined by its feeding
  relationships
• Food Web A representation of the interlocking
  food chains that connect all organisms in an
  ecosystem

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Path of Energy Flow

• Energy flow occurs in food chains in which energy
  moves through the organism in sequence
• Each level in a food chain or link is a trophic
  level
• Organisms are assigned their trophic level based
  on the number of energy transfer steps to that
  trophic level
• Ecosystems have different complexities due to
  the fact that organism soften gain energy from
  multiple sources
• This process is very inefficient and energy is
  lost at every level due to factors such as
  hunting, reproduction and respiration for some
  examples

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Path of Energy Diagram
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Diagram of Energy Loss
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How Humans have affected the Antarctic Food Web

• Hunting of the Baleen Whales
• -Being a major consumer of the
  krill population, by reducing the amount of
  whales, Humans have allowed the Krill population
  to skyrocket and in turn has allow other krill
  consuming populations to grow
• Thinning of the ozone layer
• -Because of Human induced
  ozone layer thinning, more U.V radiation(specifica
  lly over the Antarctic) has been able to reach
  the surface of the Earth. This in turn can
  damage, kill, and possibly eliminate algae in the
  Southern Ocean which forms the base of this
  ecosystems food web.
• Commercial Fishing of Krill for fishmeal for
  aquaculture industries
• -Many scientists fear that
  this could damage many Krill consuming species in
  this ecosystem as well as the ecosystem itself

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ECOLOGICAL PYRAMIDS

• By Sabrina Blanke and Samantha LaMonica

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What is an ecological pyramid?

• the flow of energy that goes from one trophic
  level to the next in a food pyramid
• - a result of the second law of thermodynamics
  (the entropy of a system never decreases)
• graphically represent the energy values of each
  trophic level
• 3 MAIN TYPES
• 1. Pyramid of Numbers
• 2. Pyramid of Biomass
• 3. Pyramid of Energy

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Pyramid of Numbers

• shows the number of organisms at each trophic
  level of a given ecosystem
• organisms at the bottom are the most abundant,
  fewer organisms as the the pyramid progresses
  upwards
• inverted pyramids are where higher trophic levels
  have more organisms than lower ones, found in
  decomposers and parasites
• limited help because they do not show the biomass
  of the organisms and do not show the amount of
  energy transferred

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Pyramid of Biomass

• illustrates the total biomass at each successive
  trophic level
• biomass is an estimate of the total mass or
  amount of living material. It measures the amount
  of fixed energy at a particular time
• units of measure for biomass vary, it is
  represented as
• 1. Total Volume
• 2. Dry Weight
• 3. Live Weight

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Pyramid of Energy

• this illustrates the energy content of the
  biomass of each trophic level
• often expressed as kilocalories per square meter
  per year
• begin with large bases and get progressively
• smaller
• energy pyramids show that most energy dissipates
• into the environment when going from one
  trophic
• level to the next

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Chapter 3!

• By Jayvon Johnson and Rebekah Levine

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Ecosystem Productivity

• Net primary productivity GPP - Plant
  cellular respiration
• (plant growth/unit area/ (total
  (/unit area/unit time)
• unit time)
  photosynthesis/
• 
  unit area/unit time)

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GPP NPP

• NPP Net Primary Productivity
• Energy in plant tissues after cellular
  respiration has occured.
• Amount of biomass found in excess of that broken
  down by a plants cellular respiration.
• Rate at which organic matter is actually
  incorporated into plant tissues for growth.

• GPP Gross Primary Productivity
• The rate at which energy is captured during
  photosynthesis.

• GPP NPP
• Referred to as primary because plants occupy the
  first trophic level in food webs.
• Expressed as energy/unit area/unit time or as dry
  weight.

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What is NPP Energy What Is It For?

• Available as food for an ecosystems consumers.
• Consumers us most of the energy for cellular
  respiration to contract muscles and to maintain
  and repair cells and tissues.
• Energy that is left is used for growth and
  production of young, secondary productivity.
• Ex Extended Drought
• Secondary productivity is any environmental
  factor that limits an ecosystems primary
  productivity.

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Cellular Respiration

• Photosynthesis in reverse
• -O2 absorbed and CO2 released
• -breakdown food and energy is released
• -glucose broken down into H2O, CO2, and energy
• -releases energy as ATP molecules

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Human Impact on Net Primary Productivity

• Humans consume far more of earths resources than
  any other of the millions of animal species.
• College students like Peter Vitousek, Stuart
  Rojstaczer, etc. did some research on this impact.

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Peter Vitousek

• Stanford University in 1986.
• Calculated how much of the global NPP is
  appropriated for the human economy and therefore
  not transferred to other organisms.
• Estimated that humans use 32 of the annual NPP
  of land-based ecosystems.
• Humans represent 0.5 of the total biomass of all
  consumers on Earth.

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Stuart Rojstaczer

• Duke University in 2001.
• Reexamined Vitouseks groundbreaking research.
• Used contemporary data sets, many of which are
  satellite-based and more accurate than the data
  Vitousek used.
• His mean value for his conservative estimate of
  annual land-based NPP appropriate by humans was
  32 like Vitouseks, although arrived using
  different calculations.

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K. Heinz Erb

• Klagenfurt University in 2007.
• Plugged agricultural and forestry statistics that
  account for 97 of Earths icefree land into a
  computer model.
• Erbs model indicates that humans appropriate
  about 25 of Earths land-based Npp for food,
  forage (for livestock), and wood.

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Consequences..!

• Human use of global productivity is competing
  with other species energy needs.
• Our use of so much of the worlds productivity
  may contribute to the loss of many species, some
  potentially useful to humans, through extinction.
• Threat to the planets ability to support both
  its nonhuman and human occupants.