1. Feeding Relationships and Energy Flow in Ecosytems

2. Ecological principles
Study of relationships between living organisms (biotic) and their environment(abiotic- sunlight,temperature, moisture,nutrients)

3. Species
Estimated million,1.8 million named we don’t know how many others may exist that we haven’t yet found “groups of organisms that resemble one another in appearance, behavior, chemistry, genetic make up and breed with one another to produce fertile offspring”

4. Levels of organization
Population – interacting individuals of the same species occupying a specific area
Community – populations of all species occupying a particular place, complex interacting network of plants, animals and microorganisms
Ecosystem – communities interacting with each other and their non-living environment
Ecosphere/Biosphere – all ecosystems

5. Characteristics of living things
Made up of cells
Characteristic DNA found in each cell
Transform matter and energy to supply their needs(metabolism)
Maintain constant internal balance(homeostasis)
Perpetuate themselves
Adaptation and evolution

6. Earth’s Life support systems – major components

7. Types of Organisms and Role in Food Chain

8. Terrestrial Food Chain and Nutrient Flow

9. Category and Type of Organism Feeds on/ Food from Examples
Trophic Level

10. Types of organisms Herbivores- eat plants (examples)
Carnivores- eat animals (examples)
Omnivores – eats plants and animals (examples)
Scavengers – eats dead organisms
Detritivores –
Detritus Feeders- live off detritus (parts and wastes of living organisms)
Decomposers- recycle organic matter in ecosystems by breaking down dead organic matter and releasing the inorganic compounds into the soil and water to be used as nutrients by producers

11. Category and Type of Organism Feeds on/ Food from Examples
Trophic Level

12. Decomposers Bacteria ,fungi
Cycle nutrients by breaking down dead organic matter, releases simple inorganic compounds into the soil, taken up by producers

13. Category and Type of Organism Feeds on/ Food from Examples
Trophic Level

14. Feeding RelationShips & Trophic Levels
Trophic Level- step in a food chain or food web, “feeding step/stage”
1. Producers/Autotrophs-
Photosynthesizers- green plants that perform photosynthesis
Chemoautotrophs- obtain carbon through chemosynthesis- the biological conversion of carbon molecules (usually CO2 or CH4 ) and nutrients into organic matter using the oxidation of inorganic molecules or methane as a source of energy
2. Primary consumers – herbivores
3. Secondary consumers – carnivores that feed on herbivores or omnivores
4. Tertiary consumers – feed on other carnivores

15. Consumers Producers Herbivore Omnivore Carnivore Decomposer Scavenger
Category and Type
of Organism
Feeds on/ Food from
Examples
Trophic Level
Producers
Creates own food with energy from the sun
Grass, flowers, acorns, trees
First/Bottom
Consumers
Herbivore
Producers only
Deer, cows, sheep, grasshoppers
Primary consumer
Omnivore
Producers and consumers
Bears, pigs, gorillas, rats, raccoons, cockroaches, humans
Primary/ secondary consumer
Carnivore
Consumers only
Lions, hawks, snakes, sharks, spiders, alligators, whales
Secondary/Tertiary consumer
Decomposer
Breaks down dead organisms and returns nutrients to soil, water and air
Fungi and bacteria
Tertiary consumer
Scavenger
Eats dead and decaying organisms
Vultures, hyena

16. PhotoSynthesis 6H20 + energy + 6CO2  C6H12O6 + 6O2
Performed by green plants
Plants/Producers use photosynthesis to make the sugars they need to survive. The equation for photosynthesis is:
Water + Sun energy + carbon dioxide  Glucose (sugar) and oxygen
6H20 + energy + 6CO2  C6H12O6 + 6O2

17. Food webs and Energy flow-complex network of interconnecting food webs

18. Food chains-all organisms are potential food for other organisms
Always start with a producer, without a producer there is no energy for the first level
The arrow shows the path of energy flow
This means that the arrow points to the organism doing the eating or “to the belly”

19. Food webs show all of the feeding relationships in the ecosystem
A food web should show a variety of plants and animals and how they relate in terms of feeding relationships

20. Food web – grazing
Plants – herbivores- carnivores- decomposers

21. Food web – detrital
Producers – decomposers – detrivores (forests,
streams,
marshes)

22. Energy efficiency More trophic levels = greater energy loss
Rarely more than 4-5 trophic levels
Always very few top carnivores- not enough energy to support too many
90% of energy is used with each trophic level, 10% of original energy is still available to the next trophic level

23. Ecological pyramids
Graphic representation of organisms, energy, biomass available in an ecosystem
Ecological efficiency varies from 5-20% energy available between successive tropic levels.
About 10% efficiency

25. Biomass
The dry weight(because water is not a source of energy) of all organisms at that tropihic level. Represents the amount of stored energy
Energy in biomass transfers from one level to another(5-20%) with certain amount of energy lost as heat at each transfer(80-95%)

27. Pyramid of numbers
Graphic display estimating the number of organisms at each trophic level

28. Gross Primary Productivity (GPP)
The rate at which an ecosystem producers capture and store a given amount of chemical energy as biomass in a given length of time
Greatest – shallow waters near continent, coral reefs ,high upwelling regions of ocean
Lowest – deserts, open ocean

29. Net primary Productivity(NPP)
Rate at which producers store chemical energy by photosynthesis – rate at which producers use chemical energy by aerobic respiration
Greatest – estuaries, marshes,tropical rain forest
Lowest – open ocean, tundra, desert

31. Agricultural land
Try to increase NPP and Biomass by adding water and nutrients(Nitrogen = nitrates ; phosphorous = phosphate)

32. Total global net productivity
Land – 59%, aquatic – 49%
Open ocean with low NPP but total contribution high because of vast expanse
Tropical rain forest – nutrients in vegetation not soil, major contributor to NPP, only occupy 2% of land surface