Download Matter and Energy Fundamentals, Intro to ecosystems

Energy, Matter and Ecosystems
Objectives
• Explore matter and energy
– Matter + energy = everything
– Energy needed to organize matter
•
Understand the flow of energy and matter in living systems
– Ecosystems
E = MC2
• Energy and matter are interrelated
• There is a finite amount of matter and energy in the universe
• All of life involves shifting around energy and matter
• Photosynthesis is key to ALL of Environmental Science
Photosynthesis
• Plants and animals use ENERGY to organize MATTER
• Plants store energy from the sun in chemical bonds
• Animals use energy from those bonds
Photosynthesis
CO2 + H2O + energy à C6H12O6 + O2
Plants are on the left (they use sunlight to convert carbon dioxide and water into
sugars and oxygen)
WE are on the right (we eat sugars, we breathe in oxygen, and we use the
energy to live)
Photosynthesis
Structure of Matter
• Atoms are the fundamental units of matter
• Examples
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Carbon
Hydrogen
Uranium
Structure of Matter
• The nucleus of an atom is made up of protons (which have a positive charge)
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and neutrons
Electrons (which have a negative charge) circle the nucleus
Hydrogen and Carbon
Hydrogen
Structure of Matter (cont)
• Electrons from two or more atoms interact to form
molecules and ions
• Molecules are atoms bonded together into stable units
• Compounds are formed when two or more different
kinds of atoms bind to one another
Water
• H2O
• Molecules form
“hydrogen bonds”
• Dissociates into
– hydroxyl ion (OH-)
– hydrogen ion (H+)
Hydrogen bonds
Water animation
Proton exchange
Ions
• Ions are atoms or molecules with more or fewer total electrons than protons
• Ions “dissociate” in solution
–
H2O into H+ and OH-
–
NaCl (table salt) to Na+ and Cl-
Hydrogen Ions
NaCl
Acids, Bases and pH
• Strength of acid or base is represented by pH number - measures hydrogen
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•
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ion concentration.
7 = neutral
0-6 = acidic (more H+ than OH-)
8-14= basic (more OH- than H+)
Figure Similar to 3.4
States of Matter
• States: solid, liquid, gas
• Not states: Suspension, dissolution
• State depends on the amount of kinetic energy
• Energy and matter are inseparable
Water
Ice
Law of Conservation of Matter
Matter can be neither created nor destroyed, the atoms involved can only be
rearranged
ENERGY
• Energy is the ability to perform useful work.
– Kinetic Energy - energy contained by moving objects
– Potential Energy - energy due to relative position
Examples
• Heat (Thermal energy)
• Chemical bonds
• Nuclear energy
• Insolation
• Hydrological
First Law of Thermodynamics
•
In any physical or chemical reaction, energy cannot be created or destroyed.
It can only be changed from one form to another.
“You can’t get ahead”
Second Law of Thermodynamics
• In any physical or chemical reaction, as energy is changed from one form to
•
another, some energy must be degraded to lower quality (usually in the form of
heat)
Entropy (randomness) increases
“You can’t break even”
Implications of the two laws
• In a closed system,
– the amount of energy remains constant
– the availability of that energy decreases
•
The Earth is not a closed system
Energy Quality
• High quality (low entropy) energy is available to perform useful work
•
(electricity)
Low quality energy is not available to perform useful work (heat in the ocean)
Matter and Energy
• Organisms use ENERGY to organize MATTER
• Plants photosynthesize
• Plants and animals access stored chemical energy
• Humans have learned to use energy to organize matter in additional ways
Chemical Reactions
• Chemical bonds
– physical attractions between atoms
– interaction of electrons
– Contain energy
•
Chemical reactions
– chemical bonds are formed or broken
Chemical Reactions in Living Things
• Organisms use energy to organize simple molecules into more
complex molecules
– Energy storage (fat)
– Structure (bone, muscle)
– Functional (enzymes, hemoglobin)
• In order to create complex molecules, they must destroy other
molecules
• Entropy increases as useful energy is dissipated as heat
Consuming energy
• C6H12O6 + 6O2 à 6CO2 + 6H2O + energy
• Glucose + Oxygen produces Carbon Dioxide + Water, and
releases energy
• Fire is the rapid release of stored energy
• Cellular respiration is a more gradual release of energy
Cellular respiration
• The process of releasing chemical-bond energy from food cellular respiration
• All living organisms convert high-quality food energy into low-quality heat
•
energy (second law)
Most food energy is dissipated as heat
Environmental Implications of Energy Flow
• Heat produced during energy conversion is dissipated
– Chemical reactions
– Friction between moving objects
Other uses of stored energy
• Fats (and oils) are even more organized—more energy per molecule
• Proteins are also more organized, and serve additional purposes besides
energy storage (e.g. pheromones and hemoglobin)
Efficiency
• Heat is lost during any energy conversion
• The extent to which useful energy is converted into other useful energy is
•
called “efficiency”
The second law implies that no conversion can be 100% efficient
Discussion
• How much of the energy in gasoline is actually used to move people?
•
What happens to the rest?
Efficiency: Light Bulbs
• Convert electrical energy to light, plus waste heat
• Incandescent:
– Low short-term cost
– Attractive light
– High long term cost (inefficient, breakable)
• Fluorescent:
– Low long-term cost (efficient, resilient)
– High short-term cost
– “Ugly” light
Heat loss
• Light bulbs heat surrounding air
• Humans generate heat just by living and even more by doing
• Manufacturing facilities release heat in steam, hot air, or as radiated energy
• Automobiles release heat
Ecosystems and Energy
• Ecology
– Levels of Biological Organization
– Organism interactions
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Energy and Matter Flow Through Systems
– Pyramids
Ecology
• From the Greek root “study of the house”
• Study of relationships and interactions
– Biotic
– Abiotic
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Multiple levels of biological organization
From cch 3
Levels of biological organization
• Species
– Population
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Community
Ecosystem
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Biome
Biosphere
Figure 4-6
Energy Flow
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Energy flow is the passage of energy in a one-way direction through an
ecosystem.
– Entropy increases
Trophic levels
– producers
– consumers
– decomposers
Figure 4.7
Figure 3.13
Figure 3.15
Figure 3.14
Food Chains and Food Webs
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Food chains
– Corn is eaten by a hog which is then eaten by a person
Food webs
– A hog may eat both corn and oats, and a person will eat bacon, lettuce and
tomato on rye (hold the mayo)
Figure 4.10
Pyramids
• Pyramids are useful for understanding ecosystems
• Pyramid of numbers
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Pyramid of biomass
Pyramid of energy
Figure 4.11
Figure 3.16
Figure 4.12
Figure 3.13
Ecosystems and Living Organisms
• Organism Interactions
• Ecological Niche
• Species Diversity
• Evolution
• Ecological Succession
Interactions among organisms
• There are three major categories of organism
interactions
– Predation
– Symbiosis
– Competition
Predation
• Predation occurs when one organism consumes another.
It is the fundamental
path by which energy and matter moves through trophic levels
Symbiosis
• Symbiosis is a close relationship or association between members of two or
more species
– Mutualism (lichens)
– Commensalism (bees and flowers)
– Parasitism (mosquitoes and people)
Competition
• Competition occurs when two or more individuals attempt to use
the same common resource (i.e. food, sunlight, water)
• Intraspecific Competition takes place within a population
– Example: giraffe neck length
• Interspecific Competition occurs between species
– Example: both humans and birds want apples
Ecological Niche
•
A niche includes all physical, chemical, and biological aspects of an
organism’s existence
– Limiting Factors
– Competitive Exclusion
– Resource Partitioning
Species Diversity
(Species Richness)
• Influential factors
– Ecological Niches (+)
– Ecotone and Edge Effect (+)
– Geographic isolation (-)
– Species Dominance (-)
– Habitat Stress (-)
– Geological history (+)
Review
• Energy and Matter = Everything
• Producers use solar energy to organize C, H and O
– Use that energy to do complicated things
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Consumers eat producers or other consumers
– Use that energy to do complicated things
Review
• Organisms interact
• Individual level
– Complex interactions
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Food chains, food web
Entropy increases up the food chain
Figure 3.9
Figure 3.13
Figure 3.2
Figure 4.8