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. Mo re pro duc er bio ma ss Mor e pho tosy nthe sis Mor e che mic al ene rgy stor ed in org anic mat ter. 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 CO H 2 O + solar energy  C 6 H 12 O O 2 Cellular Respiration: – Aerobic Respiration: energy releasing process. – C 6 H 12 O O 2  6CO H 2 O + 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 output NUTRIENTS 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

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 KONTROL PRODUKSI 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

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

PRODUKSI PRIMER BIOMASA 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 PRIMER DANAU

. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012 PRODUKSI PRIMER DANAU

. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012 PRODUKSI PRIMER DANAU

. Sumber: www2.yk.psu.edu/~mph13/EnergyFlow.18.ppt...………… diunduh 19/12/2012 PRODUKSI PRIMER DANAU

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