Ecosystems: Components, Energy Flow, and Matter Cycling

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Ecosystems Components, Energy Flow, and Matter
Cycling

• All things come from earth, and to earth they
  all returnMenander

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Ecosystem Organization

• Organisms
• Made of cells
• Eukaryotic vs Prokaryotic
• Species
• Groups of organisms that resemble one another in
  appearance, behavior, and genetic make up
• Sexual vs Asexual reproduction
• Production of viable offspring in nature
• 1.5 million named 10-14 million likely
• Populations
• Genetic diversity
• Communities
• Ecosystems
• Biosphere

Fig. 4.2, p. 66
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Earths Life Support Systems

• Troposphere
• To 11 miles
• Air is here
• Stratosphere
• 11 to 30 miles
• Ozone layer
• Hydrosphere
• Solid, liquid, and gaseous water
• Lithosphere
• Crust and upper mantle
• Contains non-renewable res.

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Sustaining Life on Earth

• One way flow of high quality energy
• The cycling of matter (the earth is a closed
  system)
• Gravity
• Causes downward movement of matter

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Major Ecosystem Components

• Abiotic Components
• Water, air, temperature, soil, light levels,
  precipitation, salinity
• Sets tolerance limits for populations and
  communities
• Some are limiting factors that structure the
  abundance of populations

• Biotic Components
• Producers, consumers, decomposers
• Plants, animals, bacteria/fungi
• Biotic interactions with biotic components
  include predation, competition, symbiosis,
  parasitism, commensalism etc.

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Limiting Factors on Land in H2O

• Terrestrial
• Sunlight
• Temperature
• Precipitation
• Soil nutrients
• Fire frequency
• Wind
• Latitude
• Altitude

• Aquatic/Marine
• Light penetration
• Water clarity
• Water currents
• Dissolved nutrient concentrations
• Esp. N, P, Fe
• Dissolved Oxygen concentration
• Salinity

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The Source of High Quality Energy

• Energy of sun lights and warms the planet
• Supports PSN
• Powers the cycling of matter
• Drives climate and weather that distribute heat
  and H2O

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Fate of Solar Energy

• Earth gets 1/billionth of suns output of energy
• 34 is reflected away by atmosphere
• 66 is absorbed by chemicals in atmosphere
  re-radiated into space
• Visible light, Infrared radiation (heat), and a
  small amount of UV not absorbed by ozone reaches
  the atmosphere
• Energy warms troposphere and land
• Evaporates water and cycles it along with gravity
• Generates winds
• A tiny fraction is captured by photosynthesizing
  organisms
• Natural greenhouse effect vs. Global Warming

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Primary Productivity

• The conversion of light energy to chemical energy
  is called gross primary production.
• Plants use the energy captured in photosynthesis
  for maintenance and growth.
• The energy that is accumulated in plant biomass
  is called net primary production.

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Primary Productivity

• NPPGPP-respiration rate
• GPP RATE at which producers convert solar energy
  into chemical energy as biomass
• Rate at which producers use photosynthesis to fix
  inorganic carbon into the organic carbon of their
  tissues
• These producers must use some of the total
  biomass they produce for their own respiration
• NPP Rate at which energy for use by consumers is
  stored in new biomass (available to consumers)
• Units Kcal/m2/yr or g/m2/yr
• How do you measure it? AP Lab Site
• Most productive vs. least productive

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What are the most productive Ecosystems?
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Fate of Primary Productivity and Some important
questions

• Since producers are ultimate source of all food,
  why shouldnt we just harvest the plants of the
  worlds marshes?
• Why dont we clear cut tropical rainforests to
  grow crops for humans?
• Why not harvest primary producers of the worlds
  vast oceans?
• Vitousek et al Humans now use, waste, or
  destroy about 27 of earths total potential NPP
  and 40 of the NPP of the planets terrestrial
  ecosystems

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Biotic Components of Ecosystems

• Producers (autotrophs)
• Source of all food
• Photosynthesis
• Consumersheterotroph
• Aerobic respiration
• Anaerobic respiration
• Methane, H2S
• Decomposers
• Matter recyclers
• Release organic compounds into soil and water
  where they can be used by producers

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Trophic Levels

• Each organism in an ecosystem is assigned to a
  feeding (or Trophic) level
• Primary Producers
• Primary Consumers (herbivores)
• Secondary Consumer (carnivores)
• Tertiary Consumers
• Omnivores
• Detritus feeders and scavengers
• Directly consume tiny fragments of dead stuff
• Decomposers
• Digest complex organic chemicals into inorganic
  nutrients that are used by producers
• Complete the cycle of matter

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Detritivores vs Decomposers stop
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Energy Flow and Matter Cycling in Ecosystems

• Food Chains vs. Food Webs
• KEY There is little if no matter waste in
  natural ecosystems!

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Generalized Food Web of the Antarctic
Note Arrows Go in direction Of energy flow
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Food Webs and the Laws of matter and energy

• Food chains/webs show how matter and energy move
  from one organism to another through an ecosystem
• Each trophic level contains a certain amount of
  biomass (dry weight of all organic matter)
• Chemical energy stored in biomass is transferred
  from one trophic level to the next
• With each trophic transfer, some usable energy is
  degraded and lost to the environment as low
  quality heat
• Thus, only a small portion of what is eaten and
  digested is actually converted into an organisms
  bodily material or biomass (WHAT LAW ACCOUNTS FOR
  THIS?)

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Food Webs and the Laws of matter and energy

• Food chains/webs show how matter and energy move
  from one organism to another through an ecosystem
• Each trophic level contains a certain amount of
  biomass (dry weight of all organic matter)
• Chemical energy stored in biomass is transferred
  from one trophic level to the next
• With each trophic transfer, some usable energy is
  degraded and lost to the environment as low
  quality heat
• Thus, only a small portion of what is eaten and
  digested is actually converted into an organisms
  bodily material or biomass (WHAT LAW ACCOUNTS FOR
  THIS?)
• Ecological Efficiency
• The of usable nrg transferred as biomass from
  one trophic level to the next (ranges from 5-20
  in most ecosystems, use 10 as a rule of thumb)
• Thus, the more trophic levels or steps in a food
  chain, the greater the cumulative loss of useable
  energy

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Food Webs and the Laws of matter and energy

• Ecological Efficiency
• The of usable energy transferred as biomass
  from one trophic level to the next (ranges from
  5-20 in most ecosystems, use 10 as a rule of
  thumb)
• Thus, the more trophic levels or steps in a food
  chain, the greater the cumulative loss of useable
  energy

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Pyramids of Energy and Matter

• Pyramid of Energy Flow
• Pyramid of Biomass

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Ecological Pyramids of Energy
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Ecological Pyramids of Biomass
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Implications of Pyramids.

• Why could the earth support more people if the
  eat at lower trophic levels?
• Why are food chains and webs rarely more than
  four or five trophic levels?
• Why do marine food webs have greater ecological
  efficiency and therefore more trophic levels than
  terrestrial ones?
• Why are there so few top level carnivores?
• Why are these species usually the first to suffer
  when the the ecosystems that support them are
  disrupted?

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ATMOSPHERE
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LITHOSPHERE
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HYDROSPHERE
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ECOSPHERE
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Ecosystem Services and Sustainability
Lessons From Nature!

1. Use Renewable Solar Energy As Energy Source
2. Recycle the chemical nutrients needed for life

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Matter Cycles

• You are responsible for knowing the water,
  carbon, nitrogen, sulfur, and phosphorus cycles
• Know major sources and sinks
• Know major flows
• Know how human activities are disrupting these
  cycles

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BIOGEOCHEMICAL CYCLES
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Fundamentals of biogeochemical cycles

• All matter cycles...it is neither created nor
  destroyed...
• As the Earth is essentially a closed system with
  respect to matter, we can say that all matter on
  Earth cycles .
• Biogeochemical cycles the movement (or cycling)
  of matter through a system

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• by matter we mean elements (carbon, nitrogen,
  oxygen) or molecules (water) so the movement of
  matter (for example carbon) between these parts
  of the system is, practically speaking, a
  biogeochemical cycle
• The Cycling Elements macronutrients required
  in relatively large amounts "big six"
• carbon , hydrogen , oxygen , nitrogen ,
  phosphorous sulfur

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HYDROLOGIC CYCLE
CONNECTS ALL OF THE CYCLES AND SPHERES TOGETHER
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Water Quality Degradation
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IMPORTANCE OF CARBON CYCLE
CARBON IS THE BACKBONE OF LIFE!
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Carbon Cycle
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MARINE CARBON CYCLE
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TERRESTRIAL CARBON CYCLE
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The Nitrogen Cycle
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Nitrogen is a key element for

• amino acids
• nucleic acids (purine, pyrimidine)
• cell wall components of bacteria (NAM).

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Nitrogen Cycle
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IMPORTANCE OF PHOSPHOROUS CYCLE

• 1.Phosphorous is an essential nutrient of both
  plants and animals.
• 2. It is part of DNA molecules which carry
  genetic information.
• 3. It is part of ATP and ADP) that store
  chemical energy for use by organisms in cellular
  respiration.
• 4. Forms phospholipids in cell membranes of
  plants and animal cells.
• 5. Forms bones, teeth, and shells of animals as
  calcium phosphate compounds.

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PHOSPHOROUS CYCLE
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http//3.bp.blogspot.com/_n9nytwY_jek/TS8oQCN8xHI/
AAAAAAAAACU/v5pYyLVVZkU/s640/eutrophication.gif
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https//iboess.wikispaces.com/5.4Eutrophication
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SULFUR CYCLE
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ROCK CYCLE
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HUMAN IMPACTS ON ROCK CYCLE

• 1. Humans are excavating minerals and removing
  rock material. It takes millions of years for
  rock to form.
• 2. Humans remove sediments for building
  materials. This removes sediments that may form
  sedimentary rocks in the future.
• 3. Humans are filling in wetlands (peatlands),
  area that will form future coal beds.

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Works Cited

1. http//science.pppst.com/carboncycle.html
2. westernreservepublicmedia.org/earthmotion3/images/
   Carbon_Cycle.ppt
3. clima-dods.ictp.it/d3/annalisa/ocean_sv/lecture1.p
   pt
4. www.geology.wmich.edu/Koretsky/envs2150/Pcycle_1.p
   pt