1 Energy Flow in an Ecosystem

2 Energy Flow Energy in an ecosystem originally comes from the sunEnergy in an ecosystem originally comes from the sun Energy flows through Ecosystems from producers to consumersEnergy flows through Ecosystems from producers to consumers –Producers (make food) –Consumers (use food by eating producers or other consumers)

3 Producers Sunlight is the main source of energy for most life on earth.Sunlight is the main source of energy for most life on earth. Producers contain chlorophyll & can use energy directly from the sunProducers contain chlorophyll & can use energy directly from the sun

4 Autotrophs An Autotroph is any organism that can produce its own food supply!An Autotroph is any organism that can produce its own food supply! Autotrophs are also called ProducersAutotrophs are also called Producers Plants, algae, some protists, & some bacteria are examplesPlants, algae, some protists, & some bacteria are examples

5 Niche of a Producer Captures energy and transforms it into organic, stored energy for the use of living organisms.Captures energy and transforms it into organic, stored energy for the use of living organisms. May be photo-autotrophs using light energy (e.g. plants)May be photo-autotrophs using light energy (e.g. plants) May be chemo-autotrophs using chemical energy (e.g. cyanobacteria)May be chemo-autotrophs using chemical energy (e.g. cyanobacteria)

6 Photoautotroph Producer That Captures Energy from the sun by: –Photosynthesis Adds Oxygen to the atmosphereAdds Oxygen to the atmosphere Removes Carbon Dioxide from the AtmosphereRemoves Carbon Dioxide from the Atmosphere Algae

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Photosynthesis – 6CO 2 + 6H 2 O + chlorophyll  C 6 H 12 O 6 + 6O 2 8

9 CELLULAR RESPIRATION is the chemical reaction that releases the energy (ATP) in glucose. 6O 2 + C 6 H 12 O 6 ---> 6H 2 O + 6CO 2 + energy

Cellular respiration reactions 10

11 On LandOn Land –Plants In The SeaIn The Sea –Algae Tidal Flats & Salt MarshesTidal Flats & Salt Marshes –Cyanobacteria Habitat of Photoautotrophs

12 Chemoautotrophs Capture energy from the bonds of inorganic molecules such as Hydrogen SulfideCapture energy from the bonds of inorganic molecules such as Hydrogen Sulfide Process is called ChemosynthesisProcess is called Chemosynthesis Often occurs in deep sea vents or gut of animalsOften occurs in deep sea vents or gut of animals Called a Black smoker (thermal vent)

13 Tube Worms living in Black Smoker

14 Some energy in the primary consumer is STORED & not lost to the atmosphere or used by the consumer itself. This energy is available for another consumer (predator).

15 Consumers Heterotrophs eat other organisms to obtain energy. (e.g. animals) HerbivoresHerbivores –Eat Only Plants CarnivoresCarnivores –Eat Only Other Animals Animals

Consumers Heterotrophs eat other organisms to obtain energy. Omnivores (Humans) Eat Plants & Animals Detritivores (Scavengers) Feed On Dead Plant & Animal Remains (buzzards) Decomposers Fungi & Bacteria

17 Feeding Relationships Energy flows through an ecosystem in one direction from producers to various levels of consumers

18 The transfer of energy from the sun to producer to primary consumer then to higher order consumers can be shown in a FOOD CHAIN.

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20 Feeding Relationships Food ChainFood Chain –Simple Energy path through an ecosystem Food WebFood Web –More realistic path through an ecosystem made of many food chains

21 Food Chain Producer ( trapped sunlight & stored food) 1 st order Consumer 2 nd Order Consumer 3 rd Order consumer 4 th Order Consumer

22 Name the Producer, Consumers & Decomposers in this food chain:

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24 Food Web

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26 Trophic Levels Each Level In A Food Chain or Food Web is a Trophic Level. ProducersProducers –Always The First Trophic Level –How Energy Enters The System HerbivoresHerbivores –Second Trophic Level

27 Trophic Levels Carnivores/OmnivoresCarnivores/Omnivores –Make Up The Remaining Trophic Levels Each level depends on the one below it for energy.

28 Ecological Pyramids Graphic Representations Of The Relative Amounts of Energy or Matter At Each Trophic Level May be: Energy Pyramid Biomass Pyramid Pyramid of Numbers

29 Energy Pyramid

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31 Biomass Pyramid

32 An energy pyramid follows the 10% rule – only 10% of the energy available at one trophic level is transferred to the next trophic level.

33 Trophic levels- 10% rule

34 Pyramid of Numbers

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36 Identify the Producers, Consumers, & Decomposers: Count the Food Chains!

37 Carbon Cycle All living things are made of carbon. Carbon is also a part of the ocean, air, and even rocks. Because the Earth is a dynamic place, carbon does not stay still. It is on the move! Carbon dioxide is a greenhouse gas and traps heat in the atmosphere. Without it and other greenhouse gases, Earth would be a frozen world. But humans have burned so much fuel that there is about 30% more carbon dioxide in the air today than there was about 150 years ago, and Earth is becoming a warmer place.

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39 Nitrogen fixation Three processes are responsible for most of the nitrogen fixation in the biosphere: –atmospheric fixation by lightning –biological fixation by certain microbes — alone or in a symbiotic relationship with some plants and animalssymbiotic –industrial fixation

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41 What are some ways that humans disturb ecosystems? Humans upset the homeostasis of ecosystems –Monoculture –destruction of habitats –biocides – bioaccumulation –pollution – (acid rain)

42 Why is biodiversity so important? More healthy ecosystems with more links Preservation of genetic diversity – ensures survival Some plants are providing medicines that are very useful Chance to learn about many different species is lost

43 What are we doing to preserve our natural areas? Establishing wilderness areas – no engines allowed Replanting deforested areas Establishing breeding population, reintroducing species, relocating Genetic diversity preserved in freezers! Crossing species

44 Resources fig.cox.miami.edu/Faculty/Dana/105F00_13.html s.gifhttp:// s.gif ges/N/NitrogenCycle.htmlhttp://users.rcn.com/jkimball.ma.ultranet/BiologyPa ges/N/NitrogenCycle.html