Fig. 49.2, p. 876

energy input from sun

nutrientcycling

PHOTOAUTOTROPHS(plants, other producers)

HETEROTROPHS(consumers, decomposers)

energy output (mainly heat)

Chapter 49

Producers

Terms associated with Producers

• Autotroph: Obtain energy from inorganic sources.

• Phototrophs (collect energy from sunlight)

• Chemotrophs (collect energy from chemicals in their environment)

Consumers

Terms associated with Consumers• Heterotroph: Obtain energy from organic

sources.• Herbivores (feed off plants), • Carnivores (feed off of other consumers), • Omnivores (feed off both consumers and

producers),• Decomposers (digest food outside of body), • Detrivores (internally ingest dead and decaying

matter)

Trophic (energy) levels

Primary Consumer: Feed of producers

Secondary Consumer: Feed of 1st level consumer.

Tertiary Consumer: Feed off 2nd level and below.

Quaternary Consumer: Feed off 3rd level and below.

leopard seal

Adelie penguin

fishes, squid

skua

petrel

emperor penguin

Weddell seal

killer whale

blue whale

krill

phytoplankton

Label each organism above with appropriate trophic level.

Fig. 49.7, p. 879

Producers (photosynthesizers)

Producers (photosynthesizers)

ENERGY TRANSFERS:

ENERGY TRANSFERS:

energy lost at each conversion step from one trophic level to the next

energy lost at each conversion step from one trophic level to the next

ENERGY INPUT:

ENERGY INPUT:

herbivores

carnivores

decomposers

decomposers

detritivores

energy in organic wastes, remains

energy in organic wastes, remains

ENERGY OUTPUT

ENERGY OUTPUT

energy losses as metabolic heat and as net export from ecosystem

energy losses as metabolic heat and as net export from ecosystem

energy inputs, outputs also occur between the two food webs

10% Rule

On average, only 10% of the energy obtained at one trophic level is transferred to the next trophic level.

Where does this energy go?

Fig. 49.12, p. 882

ENERGY INPUT:

17,000,000 kilocalories

ENERGY TRANSFERS:

incoming solar energy not harnessed:

producers

herbivores

carnivores

top carnivores

decomposers, detritivores

1,679,190 (98.8%)

20,810 (98.8%)

transferred to the next trophic level:

Energy still in organic wastes and remains

Energy losses as metabolic heat and as net export from the ecosystem:

ENERGY OUPUT:

TOTAL ANNUAL ENERGY FLOW:

4,245 3,368 13,197

383

21

720

272

165

5,060

2,265

90

20,810 + 1,679,190

1,700,000(100%)

Biological Magnification

Situation in which fat-soluble or indigestible chemicals accumulate in organisms. A concern for animals feeding at higher tropic levels.

• Urine is water-based, so doesn’t carry fat-soluble materials out of body.

• Case of DDT

Respiration

How living organisms get energy from ‘burning’ food (usually involves oxygen)

Glucose + Oxygen = Carbon Dioxide + Water + Useable Energy

Photosynthesis

Process by which autotrophs convert solar energy into useful chemical energy (sugar).

Carbon Dioxide + Water = Glucose + Oxygen

Process of carbon fixation. (Fix as it making it useful for life)

Productivity

Measure of how much glucose/food is made.

How broad is the base of the energy pyramid? What factors make an environment more productive?

a. b. c.

Productivity

Gross Primary Productivity, which is the total amount of energy fixed in the process of photosynthesis for an ecosystem

Net Primary Productivity is the total amount of energy fixed by photosynthesis minus the amount of energy used by autotrophs in respiration

Dissolved Oxygen Lab

In a bottle filled with lake water, label processes going on (respiration, photosynthesis, both, or neither)…

When bottle is in the dark-

When the bottle is in the light-

What influences DO levels?

Altitude:

Temperature:

Movement:

Salinity:

Plants:

Animals/Decay: