Ecosystem Ecology - Energy

How does energy move through ecological systems?

Linked by the fl__ of en____ and the cyc____ of nut____s needed to sustain life

Linked by the flow of energy and the cycling of nutrients needed to

sustain life

What are the relevant forms of energy to life on the planet?

• Li___

• Chem____-b___ energy

• Mot___

• H__t

• light

• Chemical-bond energy

• Motion

• Heat

Flow of Energy in Ecosystems

Gross primary productivity (GPP)

r_w r_t_ new or___c mat__r syn____

Net primary productivity (NPP) - GPP resp_____

• L__s to resp____, he__

raw rate new organic matter synthesis

GPP – respiration

• Loss to respiration, heat

Trophic levels

• Prim___ pro____

• Cons______

• Deco_______

primary producers

Consumers

Decomposers

Primary producers - (autotrophs) capture li____ en____

• DO NOT create en____

• Tr___f____ en_____

(autotrophs) capture light energy

• DO NOT create energy!

• TRANSFORM energy!

Consumers - e__ liv____ or_____

• prim____, sec_____y, etc

Eat living organisms

• primary, secondary, etc

1. ?

2. ?

3. ?

Decomposers, consumer, primary producer

1. Consumer

2. Producer

3. Decomposer

Tropic levels

Food chain: one possible pathway of energy flow ——> simplistic

Some con____ participate in more than o__ food chain

Some org_____ feed at mul____ trophic levels

Consumers, one

Organisms, multiple

1. ?

2. ?

3. ?

Decomposers, consumer, producer

1. Consumer

2. Decomposer

3. Producer

Trophic levels

Food web: more complex

• includes all org____ interacting in the eco______

includes all organisms interacting in the ecosystem

Why does energy loss occur when it passes through biological systems?

50% straight into fe__s

33% to cell_____ resp______

17% converted into bio____s (available to next consumer)

Feces

Cellular respiration

Biomass

__% straight into feces

__% to cellular respiration

__% converted into biomass

50%

33%

17%

The 10% rule:

When en_____ is passed in an eco_____ one trop___ level to the next, only 10% of en____ will be passed on

When energy is passed in an ecosystem one trophic level to the next, only 10% of energy will be passed on

Why is it more efficient to feed lower on the food chain?

90% is used for c___ res_______n or unu___/excr_____

90% is used for cell respiration or unused/excreted

Human effects on net primary productivity

• directly harv____d (tim___, f____, etc)

• Prevented through la__ cha___ (deve_____)

• Destroyed by fi__

Directly harvested (timber, food, etc)

Prevented through land change (development)

Destroyed by fire