Principles of Ecology

• Ecology – study of relationships between living and nonliving parts of the world

• Ernst Haeckel (1866) – first to use the word to name the study of how organisms fit into their environment

Linnean Society of London

Parts of the Environment

• Abiotic factors – non-living parts of an organism’s environment– Air currents, temperature,

moisture, light, soil

• Biotic factors – all the living things that inhabit the environment

Levels of Organization

Organism

Population

Community

Ecosystem

Biosphere

Biome

Niche vs. Habitat vs. Ecosystem

• Ecosystem – all the organisms in a given area and the abiotic factors that affect them

• Habitat – place an organism lives out its life• Niche – role and position a species has in

its environment– Includes all biotic and abiotic interactions as an

organism meets its needs for survival– If two species are competing for the same niche,

one will most likely drive the other out and take control of the niche.

• What is your niche?

Niche vs. Habitat vs. Ecosystem

An egret lives around Jones Pond which is part of the Smith River Estuary. The egret and its mate eat fish, frogs, salamanders, snakes, crayfish, mice, aquatic insects, crickets, grasshoppers, and a variety of other insects in Jones Pond and build a nest in a tree along side the pond.

• What is the egret’s habitat?• What is the egret’s niche?• What is the egret’s ecosystem?

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Relationships

• All living things form relationships with other living things

• Symbiotic Relationship – a relationship between organisms of two different species that live together in direct contact

Commensalism

• One organism benefits. The other is not affected– Examples– Spanish moss on a tree– Barnacles on a whale– Burdock seeds on a passing animal

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Mutualism• Both organisms benefit

– Acacia tree and ants (Pseudomyrmex sp.) – tree provides food for the ants and the ants protect the tree from animals that would eat the leaves

– Lichens: algae and fungus living together. Algae provides food (photosynthesis) and the fungus provides protection and attaches the lichen to the rock or wood where it lives.

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Parasitism• One organism benefits,

the other is harmed– Some live with in the host

• Tapeworms• Heartworms• Bacteria

– Some feed on the external surface of the host• Ticks• Fleas• Mistletoe

– Most do not kill their host (at least not quickly)

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Petr Kapitola

Eric Erbe

Minster Veterinary Service

Spike

Tuesday, Dec. 2

• Daily Review

• Get ready for the quiz!

The nonliving parts of the environment are called

• A. biotic factors• B. Abiotic factors• C. Niches• D. Biomes

2. The place an organsim lives is

• A. A symbiosis• B. The bioshpere• C. biotic factor• D. Habitat

3. A niche is

•A. an organisms life expectancy

•B. an organisms role in the ecosystem

•C. all the biotic factors•D. a level on the pyramid

4. Commensalism is

• A. when both organisms benefit – birds eating parasites that may harm a horse as the horse moves through the grass and stirs them up

• B. when one organism benefits and the other is harmed – a tapeworm in a cat’s stomach

• C. when one organism benefits and the other is not affected – moss on a tree

5. Mutualism is

• A. when both organisms benefit – birds eating parasites that may harm a horse as the horse moves through the grass and stirs them up

• B. when one organism benefits and the other is harmed – a tapeworm in a cat’s stomach

• C. when one organism benefits and the other is not affected – moss on a tree

Ecosystem Requirements

• #1 - Continuous supply of Energy• #2 – A flow of energy from one

population to another

Obtaining Energy

• Autotrophs - use energy from the sun or energy stored in chemical compounds to produce energy

• Heterotrophs – must consume their energy– Herbivores– Carnivores– Omnivores– Detritivore (AKA

decomposers)

Herbivores

• Eat plants (autotrophs)

Carnivores

• Eat other heterotrophs– Predators – kill their own food– Scavengers – eat animals that are

already dead

Omnivores

• Eat both autotrophs and heterotrophs (plants and animals)

Detritivore

• AKA decomposers – decompose organic matter and return nutrients to soil, water, and air– Ex. fungus, bacteria

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Energy Flows through an Ecosystem in a Complex Network of Feeding relationships

called a FOOD WEB.

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Food Chain

Energy Pyramid

• The energy pyramid is made of several trophic levels

• A Trophic Level (or feeding level) is a group of organisms whose feeding source is the same number of steps from the Sun. – Primary Producers (Autotrophs) are the

First Trophic Level. – Primary Consumers (Herbivores) are the

Second Trophic Level. – Secondary and Tertiary Consumers

(Carnivores and Omnivores) are the Third and Fourth Trophic Levels.

– Most Animals feed at more than one Trophic Level.

Trophic Levels• Energy is Lost or Used as it Flows through

the Trophic Levels of an Ecosystem. • Producers (Plants) absorb Energy from

the Sun, but only about ½ of the Energy capture from the Sun becomes part of the Plants Body. The other ½ is used for Living and Growing or Lost as HEAT.

• At each Trophic Level, the Energy stored in an organism is about 1/10 that of the Level Below it. (10%).

Trophic Levels

• Because Energy diminishes at each successive Trophic Level, Few Ecosystems can contain more than 4 or 5 Trophic Levels.

• Organisms at Higher Trophic Levels, Large Carnivores, tend to be Fewer in number than those at Lower Trophic Levels, Producers.

Number and Biomass Pyramids

• The number of organisms at each trophic levels decreases as you step up the pyramid.

• Biomass (living organic matter) is reduced at each trophic level as well

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Bioaccumulation• Energy is not the only thing that is passed along

through the food web.• If contaminants are introduced at any level, those

organisms that consume the contaminated food, will absorb the contaminants as well.

• Because the amount of energy required gets higher at each level, those organisms have to consume more and thus can accumulate higher levels of the contaminants in their bodies – bioaccumulation.

• Example – A pesticide that you put of your yard is consumed by the grasshoppers that live there. The rat eats 10 grasshoppers. The hawk eats 3 rats. – If the grasshopper consumed 1 mg of the pesticide,

the rat ingested 10mg, and the hawk consumed 30mg.

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Wednesday, Dec. 3

•Daily Quiz

1. A cow eats corn. What is the relationship between

the cow and the corn?

• A. the cow is an autotroph and the corn is a heterotroph

• B. the cow is a heterotroph and the corn is an autotroph

• C. both are autotrophs• D. both are heterotrophs

2. As energy moves through an ecosystem, it

• A. will increase by 10% each time it moves to a new trophic level

• B. will decrease by 10% each time it moves to a new trophic level

• C. it passes on only 10% of its value to the next trophic level

• D. it passes on 90% to the next trophic level

3. On an energy pyramid, which is the lowest trophic

level that can contain carnivores?

• A. 1st level• B. 2nd level• C. 3rd level• D. 4th level

4. Why does the number of organisms decrease at ech trophic level on an energy

pyramid?

• A. that is just the way they are drawn• B. the energy is increasing at each level• C. The animals are getting smaller• D. The energy available is decreasing at

each higher level

5. Bald eagle eat mainly fish. If a lake becomes

polluted with a toxic chemical why would it also

affect the eagle?• A. because through bioaccumulation, the

poison is concentrated as it moves up the food chain

• B. because the eagle will likely swim in the water

• C. it would not affect the eagle at all

Geochemical Cycles• Geochemical Cycles are the movement of a

particular form of matter through the living and nonliving parts of an ecosystem

• Since Earth is a closed system, it must continually cycle its essential matter.

• Matter changes form but is neither created nor destroyed; it is used over and over again in a continuous cycle.

• Organisms are an important part of this cycling system.

• Matter placed into biological systems is always transferred and transformed. Matter, including carbon, nitrogen, and water, gets cycled in and out of ecosystems.

Carbon Cycle• Carbon is one of the major components of the

biochemical compounds of living organisms (proteins, carbohydrates, lipids, nucleic acids).

• Carbon is found in the atmosphere and also in many minerals and rocks, fossil fuels (natural gas, petroleum, and coal) and in the organic materials that compose soil and aquatic sediments.

• Organisms play a major role in recycling carbon from one form to another in the following processes:– Photosynthesis– Respiration– Decomposition– Conversion of biochemical

compounds

Carbon Recycling Processes

• Photosynthesis: Autotrophs take in carbon dioxide from the atmosphere and convert it to simple sugars.

• Respiration: Organisms break down glucose and carbon is released into the atmosphere as carbon dioxide.

Nitrogen Cycle• Nitrogen is the critical component of amino

acids which are needed to build proteins in organisms.

• Nitrogen is found in the atmosphere as elemental nitrogen (N2), in living organisms (in the form of proteins and nucleic acids), or in organic materials that compose soil and aquatic sediments.

• Organisms play a major role in recycling nitrogen from one form to another in the following processes:– Nitrogen-fixation– Intake of nitrogen into the

organisms– Decomposition– Denitrification

Nitrogen Recycling Processes

• Decomposition: When an organism dies or from animal waste products, decomposers return nitrogen to the soil.

• Denitrification: Denitrifying bacteria break down the nitrogen compounds in the soil and release nitrogen into the atmosphere.

Water Cycle• Water is a necessary substance for the life processes

of all living organisms.• Water is found in the atmosphere, on the surface of

Earth and underground, and in living organisms.• The water cycle, also called the hydrologic cycle, is

driven by the Sun’s heat energy, which causes water to evaporate from water reservoirs (the ocean, lakes, ponds, rivers), condense into clouds, and then precipitate back to water bodies on Earth.

• Organisms also play a role in recycling water from one form to another by:– Intake of water into the organisms– Transpiration– Respiration– Elimination

Water Recycling Processes

• Intake of water into the organisms: Organisms take in water and use it to perform life functions (such as photosynthesis or transport of nutrients).

• Transpiration: Plants release water back into the atmosphere through the process of transpiration (the evaporative loss of water from plants).

• Respiration: All organisms metabolize food for energy and produce water as a by-product of respiration.

• Elimination: Most organisms need water to assist with the elimination of waste products.

Maintaining Ecosystems

• All of the Earth’s processes help ecosystems maintain our biosphere

• Our biosphere is the inhabited portion of our planet made up of three parts:– Atmosphere– Hydrosphere– Geosphere

• Each of these systems must interact efficiently for each ecosystem to be maintained

Atmosphere• Our atmosphere is primarily composed of

materials from life’s processes.• Oxygen

– Plants and other autotrophs produce enough oxygen for themselves and other organisms through photosynthesis

– The oxygen from photosynthesis is also responsible for the ozone layer which prevents the sun’s UV radiation from reaching the Earth’s surface

• Carbon Dioxide– Oxygen is used by plants and animals for

cellular respiration which releases carbon dioxide into the atmosphere

– The processes of photosynthesis and cellular respiration help keep the concentrations of oxygen and carbon dioxide balanced.

Atmosphere

• Nitrogen– Nitrogen in the atmosphere is

maintained by the Nitrogen cycle• Water

– Water vapor in the atmosphere is maintained by the water cycle

– As water vapor condenses in the atmosphere, impurities (dust, particulates, etc) are removed from the atmosphere and fall to Earth with precipitation. Thus, the air is cleaned after a rain or snow fall.

Atmosphere Imbalance• The greenhouse effect is the normal warming

effect when gases (such as carbon dioxide, oxygen, methane, and water vapor) trap heat in the atmosphere.

• The amount of carbon dioxide in the atmosphere cycles in response to how may plants and other photosynthetic organisms cover Earth and how much carbon dioxide they absorb.

• The amount of carbon dioxide in the atmosphere also cycles in response to the degree to which oceans cover Earth. The salt water of oceans acts as a sink for carbon dioxide, absorbing what plants do not use and converting it to various salts such as calcium carbonate.

South Carolina Standard Support Documents

Hydrosphere

• The hydrologic cycle is maintained by the energy of the Sun and the effect of weather.

• The hydrologic cycle purifies water in several ways:– Evaporated water is pure water containing no

impurities.– As water seeps down through the soil and rock it is

physically filtered of impurities.– As water flow slows, heavier

particles of sediment settle out, leaving purified water to travel toward the oceans.

Geosphere• As part of the geosphere, the soils on Earth

are constantly being generated and eroded.• All soils are composed of four distinct

components – inorganic minerals, organic matter, water, and air.

• As the weathering of inorganic materials from wind, water, and ice and the decaying of organic materials continue, more soil is produced.

• Soil erosion and deposition are natural processes that move soil from one location to another due to water, wind, ice and other agents.

• In most areas, the presence of plants allows the process of soil production to be consistent with the process of soil erosion so that the overall amount of soil remains constant.

• The presence of soil in an ecosystem allows for succession to take place.

Bibliography• "High School Core Areas Academic Standards Support

Documents". South Carolina Department of Education. August 2010 <https://www.ed.sc.gov/apps/cso/standards/supdocs_hs.cfm#area_B>.

• Textbook 1• Textbook 2

Image Citations• Berger, Joseph. "Insect Images: The Source for Entomology Photos". August 2010

<www.Bugwood.org>.• "Carrion Decomposing Fungus". Qualitative Reasoning Group, Northwestern University. August 2010

<http://www.qrg.northwestern.edu/projects/marssim/simhtml/organisms/carrionfungus.html>.• "Dreamstime for Free Images and Stock Photos". Dreamstime. August 2010

<http://www.dreamstime.com/free-photos>. • Erbe, Eric. "Insect Images: The Source for Entomology Photos". USDA Agricultural Research Service.

August 2010 <www.Bugwood.org>.• Evans, Howard Ensign. "Insect Images: The Source for Entomology Photos". Colorado State University.

August 2010 <www.Bugwood.org>.• "Heartworm Disease in Dogs and Cats". Minster Veterinary Service . August 2010

<http://www.minstervet.org/heartworm.html>. • "How Well Do You Know The Energy Pyramid". Quiztron. August 2010

<http://www.quiztron.com/tests/_well_know_energy_py_quiz_124951.htm>. • "Insect Images: The Source for Entomology Photos". Center for Disease Control Archive, Centers for

Disease Control and Prevention. August 2010 <www.Bugwood.org>.• Kapitola, Petr. "Insect Images: The Source for Entomology Photos". State Phytosanitary Administration.

August 2010 <www.Bugwood.org>.• Linnean Society of London, The Darwin-Wallace Celebration held on Thursday, 1st July, 1908 . London:

Printed for the Linnean society, 1908. <www.archive.org/details/darwinwallacecel00linn >.• Meyer, John R. . "General Entomology: Trophic Levels". NC State University. August 2010

<http://www.cals.ncsu.edu/course/ent425/library/tutorials/ecology/trophic_levels.html>. • Spike, "YUCK! Worms, Part 1 Of 3, Tapeworms and Hookworms". Ask Spike Online. August 2010

<http://www.askspikeonline.com/tag/tapeworms/>.• Wild, Alex. "Alex Wild Photography". SmugMug, Inc.. August 2010 <http://www.alexanderwild.com/>.

All other images from Microsoft clip art.