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whenever predation occurs _____ occurs
a transfer in nutrients
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food chain:
- 1. predators
- 2. herbivore
- 3. primary carnivore
- 4. secondary carnivore
- 5. tertiary carnivore
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food web
- describes roles of predation and competition for food
- multiple species within a trophic level
- describes the flow of energy
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remove producer fom food web=
ecosystem will collapse
-
remove top predator from food web=
- pop. of secondary carnivores will increase
- pop. of primary carnivores will decrease and so on
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energy input
producers and consumers
-
energy output
cellular respiration (metabolism, heat) or feces for animals
-
balance output
determines available energy
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plants use _______ to produce new material, which is ______
- photosynthesis
- respiration
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animals use _____ to absorb materials and produce ____
-
implications of energy transfer
- 1. efficiancy in never 100%
- 2. nutrients can be recycled energy cannot
- 3. complexity (# of trophic levels) is set energy input
- 4. pop.s at higher trophic levels have total biomass less than that at lower levels
-
should prob get more on implications of energy transfer*
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4 important characteristics of biogeocemical cycles
- 1. nutrients are only usable/available by primary producers in ionized forms
- 2. nutrient reserves of an ecosystem have 2 sources: enviroment inputs and recycling in detritivores
- 3. usually, the ammount of nutrients being recycled are much greater than inputs and outputs
- 4. enviromental inputs (precipitation, weathering, fixation by bacteria) and outputs (run-off, evaporation)
-
ecosystems are ususally very sensitive to:
changesin inputs and outputs
-
4 compartments of nutrients
- available
- unavailable
- organic
- inorganic
-
organic available nutrients
organisms and detritus
-
ex. of organic unavailable materials
coil, oil, peat
-
ex. inorganic available nutrients
atmospere, soil, water
-
ex. of inorganic unavailable nutrients
minerals and rocks
-
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phosphorous cycle
- 1. P is bound in rock formations and in organisms
- 2. erosion and leaching washes P into ocean where it is taken into aquatic ecosystem
- 3. P atom: 1000x to go from surface to bottom to suface again, each P atom does this 100 times
- 4. P is then deposited into ocean sediments
- 5. uplift of ocean bottom, P moves from ocean to land (happens very rarely)
-
perturbations to cycles by humans
- deforestation
- addition of P to deep sea
-
deforestation increases:
loss of nutrients significantly
-
human activities contribute about:
2/3 of annual flow of P to ocean
-
addition of P to shallow water causes:
algal blooms
-
eutrophication
rapid input of nutrients to an ecosystem
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