1. Energy and Flow

2. Energy Energy runs ecosystems
It can typically be though of as food, or as materials used to make food.
Nearly all energy related to ecosystems ultimately comes from our sun
Energy Flow: transfer of energy between the organisms of a community

3. Capturing Energy Energy enters ecosystems when organisms capture it.
What type of organism captures energy?
Autotrophs (producers)- 2 types:
Photoautotrophs- capture sunlight to construct simple carbohydrates
Photosynthesis
Chemoautotrophs- harvest energy from chemical bonds of inorganic moleucles
chemosynthesis

4. Obtaining Energy
After the energy is captured by the producers, it can be transferred/acquired by other organisms called….
Heterotrophs or Consumers
Obtain their energy by eating other organisms- either producers or other consumers
Energy flows from the sun to producers, the to various consumers
The steps in which organisms transfer energy through a community is called a Food Chain

5. Food chains Feeding relationships
Level 4
Tertiary consumer
Sun
Feeding relationships
all food chains start with energy from the sun
first level of all food chains is plants- producers
Then herbivores/ omnivores
Followed by omnivores/ carnivores
most food chains go up only levels
all levels connect to decomposers
Top
carnivore
Level 3
Secondary consumer
Carnivore
Level 2
Primary consumer
Herbivore
Level 1
Producer
Fungi
Decomposers
Bacteria

6. Flow of Matter and Energy in Ecosystems
Each feeding step in a food chain, or web is referred to as a trophic level
Producers make up the first trophic level (base)- primary producers
Consumers make up the higher levels.
Primary consumers
secondary consumers
tertiary consumers
quaternary consumers
Each level relies on the one before it
berries → mice → black bear

7. Trophic levels represent links in the chain

8. Food webs
In most ecosystems, there are networks of complex, interconnecting food chains
It is a more realistic view of the trophic structure of an ecosystem than a food chain

9. Energy Flow- not perfect
When a zebra eats the grass, it does not obtain all of the energy the grass has (much of it is not eaten)
When a lion eats a zebra, it does not get all of the energy from the zebra (much of it is lost as heat)
The two (2) previous examples of energy transfer show that no organism EVER receives all of the energy from the organism they just ate
Only 10% of the energy from one trophic level is transferred to the next – this is called the 10% law

10. Energy and trophic levels= Ecological pyramids
show how energy flows through an ecosystem.
Pyramids illustrate that the amount of available energy decreases at each succeeding trophic level.
The total energy transfer from one trophic level to the next is only about 10% because organisms fail to capture and/or eat all the food energy available at the trophic level below them.
Biomass is the total weight of living matter at each trophic level

11. Loss of energy Loss of energy between levels of food chain
To where is the energy lost? The cost of living!
10-20%
growth
energy lost to daily living
only this energy moves on to the next level in the food chain
30%
cellular
respiration
50%
waste (feces)

12. Energy pyramid Loss of energy between levels of food chain
fewer animals can live in each higher level
There are always fewer animals in a level than the one previous
Numbers 1
100
100,000
1,000,000,000

13. Biomass Pyramids
Biomass= total amount of living tissue within a given trophic level
Represent the amount of potential food in a particular level
Resemble energy pyramids

14. Biomass Pyramid

15. But what about matter? n u t r i e s
Energy flows through but nutrients and matter cycle
nutrients must be recycled to be available for the next generation
decomposers return nutrients to the soil after creatures die
fungi
bacteria
decomposers

16. Nutrients cycle around… through decomposers
consumers
decomposers
producers
phosphorus
potassium
iron
carbon
nitrogen
soil
magnesium
calcium

17. Biogeochemical Cycles
Hydrologic Cycle
Phosphorus Cycle
Nitrogen Cycle
Carbon Cycle

18. Hydrologic (Water) Cycle

20. Nitrogen Cycle

21. Nitrogen Cycme

22. Nitrogen Cycle

23. Phosphorous Cycle