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KETAHANAN
EKO-SISTEM
Produktivitas
smno.psdl-ppsub.2013
ECOSYSTEM PRODUCTIVITY
Food webs, food chains, pyramids – you can also look at ecosystems through
their productivity.
Productivity is the rate at which chemical energy is produced in an ecosystem – expressed as ‘gram of
organic matter per square metre per year’
. Sumber: lynclarkson.wikispaces.com/.../4.+ECOSYSTEMS+DIFER+IN+...………… diunduh 19/12/2012
PRODUKTIVITAS EKOSISTEM
1.Gross primary productivity (GPP) is the rate at which an ecosystem's producers convert solar energy into chemical energy as biomass.
2. Net primary productivity (NPP) is the rate at which energy for use by consumers is stored in new biomass.
NPP = GPP – R [rate at which producers use biomass]
. Sumber: lynclarkson.wikispaces.com/.../4.+ECOSYSTEMS+DIFER+IN+...………… diunduh 19/12/2012
PRODUKTIVITAS PRIMER EKOSISTEM
Generally ecosystems with the highest net productivity are those with the greatest accumulated producer biomass
The higher the net primary production of an ecosystem, the more food is available for consumer organisms and the greater the biomass of consumers living in that ecosystem.
More
producer biomass
More
photosynthes
is
More
chemical
energy stored in
organic matter
. Sumber: lynclarkson.wikispaces.com/.../4.+ECOSYSTEMS+DIFER+IN+...………… diunduh 19/12/2012
PRODUKTIVITAS EKOSISTEM
WHY DO PRODUCTION RATES DIFFER?
1. Why does a desert ecosystem have a lower productivity than a tropical rainforest?
2. What affects do temperature and hours of sunlight have on productivity?
3. List some limiting factors for ecosystems?
4. Explain why Australia does not have rich fishing grounds near its coast.
. Sumber: lynclarkson.wikispaces.com/.../4.+ECOSYSTEMS+DIFER+IN+...………… diunduh 19/12/2012
AN ECOSYSTEM IN DARKNESS
1. If light is needed for photosynthesis, but does not penetrate to the depths of the ocean, how does a consumer in ocean darkness feed?
2. Explain how producers can exist in the dark depths of the ocean.
3. Explain the difference between photosynthetic organisms and chemosynthetic organisms.
4. What is the energy source for photosynthetic organisms? What is the waste product?
5. What is the energy source for chemosynthetic organisms? What is the waste product?
. Sumber: lynclarkson.wikispaces.com/.../4.+ECOSYSTEMS+DIFER+IN+...………… diunduh 19/12/2012
KEY ENERGY PROCESSES
• Photosynthesis: use of chlorophyll. Energy storing process.
– 6 CO2 + 6 H2O + solar energy C6H12O6 + 6 O2
• Cellular Respiration:– Aerobic Respiration: energy releasing
process.– C6H12O6 + 6 O2 6CO2 + 6 H2O + energy
(ATP)• Anaerobic Respiration
– Ex. Fermentation: energy releasing process used by yeast and bacteria
. Sumber: lynclarkson.wikispaces.com/.../4.+ECOSYSTEMS+DIFER+IN+...………… diunduh 19/12/2012
PRIMARY PRODUCTION AND ENERGY FLOW
ENERGY FLOWS: solar (or nuclear) input
heat outputNUTRIENTS RECYCLE: mass conservation
inorganic ↔ organic
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
TINGKAT TROFIK
• Trophic Level: Position in a food web determined by number of energy transfers from primary producers to current level:
– Primary producers occupy first level.– Primary consumers occupy second level.– Secondary consumers occupy third level.– Tertiary consumers occupy fourth level.
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUSEN – KONSUMEN
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
RANTAI MAKANAN
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
RANTAI MAKANAN
• Primary production: Fixation of energy by autotrophs in an ecosystem.– Rate of primary production: Amount of
energy fixed over a given period of time.
• Gross primary production: Total amount of energy fixed by autotrophs.
• Net primary production: Amount of energy leftover after autotrophs have met their metabolic needs.
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMER
• Bottom-Up Controls– Influences of physical and chemical
factors of an ecosystem.
• Top-Down Controls– Influences of consumers.
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
KONTROLPRODUKSI PRIMER
Actual Evapotranspiration and Terrestrial Primary
Production
• Rosenzweig estimated influence of moisture and temperature on rates of primary production by plotting relationship between annual net primary production and annual actual evapotranspiration (AET).– AET: Annual amount of water that
evaporates and transpires off a landscape.
• Cold dry ecosystems tend to have low AET.
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
Evapotranspiration and Terrestrial Primary Production
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMER NETO
• Significant variation in terrestrial primary production can be explained by differences in soil fertility.– Shaver and Chapin found arctic net primary
production was twice as high on fertilized plots as unfertilized plots.
– Bowman suggested N is main nutrient limiting net primary production in a dry tundra meadow, and N and P jointly limit production in a wet meadow.
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMER & KESUBURAN TANAH
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMER NETO
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMER
POLA PRODUKSI PRIMER AKUATIK
• Several studies have found quantitative relationship between phosphorus and freshwater phytoplankton biomass.
• Several studies support generalization that nutrient availability controls rate of primary production in freshwater ecosystems.
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMERBIOMASA ALGAE
Carpenter proposed piscivores and planktivorous fish can cause significant deviations in primary productivity.
– Carpenter and Kitchell proposed the influence of consumers on lake primary productivity propagate through food webs.
• Trophic Cascade Hypothesis
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMERDANAU
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMERDANAU
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMERDANAU
. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012
PRODUKSI PRIMERDANAU
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