Introduction to Ecology

1.1 STANDARD: Create food webs given organisms and their diet and explain the relationships between producers, consumers and decomposers in the web.

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1.2 STANDARD: Recognize relationships between organisms (predator-prey, competition, mutualism, commensalism, parasitism...) given a description of their habitat, diet and behaviors.

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1.3 STANDARD: Describe an ecosystem (our pond?) using a biomass, numbers, and energy pyramid.

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1.4 STANDARD: Explain why food chains are generally limited to 3-5 levels using the pond organisms you observed in class and an energy pyramid.

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1.5 STANDARD: Be able to discuss how each of the nutrient cycles influence food webs (water, carbon, nitrogen, phosphorus) using examples/scenarios.

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1.6 STANDARD: Using example situations, compare and contrast when you might see exponential and logistic growth. Be sure to draw the graphs and explain the similarities and differences tying in the ideas of limiting factors and carrying capacity.

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1.7 STANDARD: Discuss the concepts of awe and stewardship in ecosystem management and the role of humans. (You may want to consider our pond comparison.)

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Review

• Characteristics of Living Things
• Cells
• Grow and Develop
• Respond to the Environment
• Reproduce
• Obtain and Use Energy

Energy and Living Things

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-Relationships

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-Energy flow -- food chains/webs

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-Ecological pyramids

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Relationships -- trophic levels

• A. Producers

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• Plants, some protists, some bacteria and some archaea

Relationships -- trophic levels

• B. Consumers

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• Primary -- directly “eat” Producers
• Secondary -- “eat” Primary Consumers

Relationships -- trophic levels

• C. Decomposers (Heterotrophic)

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• technically “Consumers”
• ​

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• bacteria and fungi

Biogeochemical Cycles

a brief review...

1. Phosphorus
2. Carbon
3. Nitrogen
4. Water

Cycles -- Phosphorus

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• Algae
• Phosphorus lawn fertilizer ban

faculty.southwest.tn.edu

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Animation: https://www.sumanasinc.com/webcontent/animations/content/phosphoruscycle.html

Cycles -- Carbon

Respiration, Decay, Fuel Burning -- produce carbon dioxide (CO₂)�

Photosynthesis -- uses carbon dioxide (CO₂) to make glucose (C₆H₁₂O₆)

http://www.kidsgeo.com/images/carbon-cycle.gif

More Information: https://www.sciencelearn.org.nz/image_maps/3-carbon-cycle

Cycles -- Nitrogen

Crop Rotation

Eutrophication

http://www.physicalgeography.net/fundamentals/9s.html

http://msucares.com/crops/soils/images/nitrogen.gif

More information: https://contrib.pbslearningmedia.org/WGBH/conv20/lsps07-int-nitrogen/index.html

Cycles -- Water (Hydrologic)

http://ga.water.usgs.gov/edu/graphics/watercyclesummary.jpg

Sublimation -- http://ga.water.usgs.gov/edu/watercyclesublimation.html

Cycles -- in some cases, inorganic molecules to become part of organic material (and back again)

1. Phosphorus -- nucleotides (DNA, RNA), phospholipids
2. Carbon -- carbohydrates, lipids, nucleic acids, proteins
3. Nitrogen -- nucleotides (DNA, RNA), proteins, chlorophyll (photosynthesis)

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*not limited to these, but these are what we discussed last year when thinking about "you are what you eat!"

Relationships -- interaction between organisms

• A. Competition --��
• B. Predation --

http://wfrc.usgs.gov/fieldstations/klamath/images/avian_predation_fig2a_tern.jpg

http://www.bbc.co.uk/bitesize/standard/biology/images/animal_fight.jpg

Relationships -- interaction between organisms

• C. Symbiosis

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• 1. Mutualism --

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• Flowers and insects -- flower provides food, insect pollinates

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http://www.physicalgeography.net/fundamentals/9f.html

Relationships -- interaction between organisms

• C. Symbiosis

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• 2. Commensalism --

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• Barnacles and a whale?
• Seeds and socks

Relationships -- interaction between organisms

• C. Symbiosis

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• 3. Parasitism --

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• Head lice, tapeworms

http://www.cdc.gov/parasites/lice/head/

Energy flow

• Not all energy reaching earth’s outer atmosphere is available at earth’s surface for photosynthesis. (reflection, absorption into other materials…)

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• Plants (and other photosynthetic organisms) do not use all the energy available to them (reflect green)

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• On average plants produce about _______ Calories (kcal) per meter² per year
• (gross -- not considering loss due to respiration)
• (One food Calories = 1 kilocalorie = 1000 calories)

Energy flow

• Types of Ecosystems

http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html

Energy flow

• Types of Ecosystems

http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html

Energy flow

• As we move up a food chain, energy available decreases
• Lost in metabolism (and life function -- cellular respiration).
• Approximately 90% (this is an overall average) is lost each step up the food chain.
• Most vertebrates -approx. 98% for metabolism, 2% for growth and reproduction. (so low b/c body temp. maintenance)
• Most invertebrates -approx. 80% for metabolism, 20% for growth and reproduction.
• Plants -anywhere from 15-70% for metabolism, 30-85% for growth and reproduction.

Energy Flow

http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa_pre_2011/foodchains/foodchains2.shtml

http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html

Energy flow -- Hamburger Vs. Soy-burger

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100 Calories of Hamburger came from 1000 Calories of plant tissue

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100 Calories of Soy-burger

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Overall

• Less

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• 1000 Calories of Hamburger
• Approximately the meat from 3 Big Macs at McDonalds
• came from 10,000 Calories of plant tissue the cow ate
• 9000 of these plant Calories were lost in the life cycle of the cow before the burgers were made for us.
• Requires the Calorie production from approximately 2 square meters of land for a year. (based on the average)�
• 1000 Calories of Soy-burger
• No loss in a step between plants and humans.
• From the same 2 square meters of land for 1 year, approximately 10,000 Calories worth of soy-burgers (59!)

Energy Flow -- just averages but to get the idea with an example...

Ecological Pyramids

• Numbers

http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html

Ecological Pyramids

• Biomass

http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html

Ecological Pyramids

http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel_pre_2011/environment/populationsandpyramidsrev2.shtml

Ecological Pyramids

• Energy

1 joule = 0.000239005736 kilocalories

http://science.kennesaw.edu/~jdirnber/Bio2108/Lecture/LecEcology/54-11-NetProductPyramid-AL.jpg

Populations

• Exponential Growth --

http://image.tutorvista.com/cms/images/38/exponential-growth-graph.JPG

Populations

• Logistic Growth --

http://biology.unm.edu/ccouncil/Biology_112/Images/logistic.gif

Populations

http://www.algebralab.org/img/cb07ae0c-5106-416c-8407-38da526923c6.gif

http://zoology.muohio.edu/oris/cunn06/cs6_06.htm

http://www.isleroyalewolf.org/sites/default/files/annual-report-pdf/Annual%20Report%202015-for%20web.pdf

Human Population

http://www.globalchange.umich.edu/