microalgae have the final say

8/10/2019 Microalgae Have the Final Say

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Microalgae have the final sayon climate change

Chi-Yong Ahn & Hee-Mock Oh

Korea Research Institute of

Bioscience and Biotechnology (KRIBB)

Real and Virtual Ecosystem:The Effects of Disturbance on Biological Systems2009. 3. 26 27.


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Definition:

Heterogeneous group of photosynthetic organisms

Oxygenic photosynthesis with plants pigments (chlorophyll a)

No vascular conducting systems

Algae

Microalgae: microscopic, usually one-cell

Macroalgae: macroscopic, multicellular


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Plankton

Definition:

Any drifting organisms (animals, plants, archaea, or bacteria)

that inhabit the pelagic zone of oceans, seas, or fresh water

Phytoplankton: photosynthesis

Zooplankton: grazing


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Classification of microalgae

(Prokaryote)

(Cyanobacteria, blue-green algae)

(Eukaryote)

Chlorophyta

Euglenophyta

Chrysophyta

Phaeophyta

Pyrrophyta

Rhodophyta


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NHK,

(Prokaryotes)

(Eukaryotes)

(Multicellular

Organisms)

(Cyanobacteria)

(Billion years ago)


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Google Earth

Shark Bay


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Satellite photo of the Shark Bay

by NASA

Shark Bay:Natural World Heritage Site


8/40From Wikipedia

Stromatolite


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Photo by Warwick Hillier


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(Cyanobacteria)

() 25%

(O2)

Microalgae

Cyanobacteria

Prochlorococcus


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[NO3-

] : [PO43-

] 16:1 (atomic ratio)N:P ratio of plankton cell 16:1

106 C : 16 N : 1 P

N: biologically determined (N2fixation & denitrification)P: set by riverine input & output via burial in sediments

Phosphorus is the ul timate nutr ient

that constrains oceanic productivity.

The plankton determines the

chemical composition of the ocean.

Redfield Ratio

Alfred C. Redfield


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The World Ocean Atlas 1994 (681,381 points)

[NO3-] = 14.1[PO4

3-]1.53

N:P ratio in the global ocean

14.6


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High-nutrient,

Low-chlorophyll

Geographical locations of low N:P ratio

Tyrrell, T. & C. S. Law.1997.Nature387: 793-796.


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What Redfield did not anticipate

- Nitrogen f ixers are limi ted by iron (Fe).

- They require relatively high iron demands in nitrogenase and PS I .

Iron hypothesis

- High-nutr ient, low-chlorophyll (HNLC) region

: equator ial & subtropical South Pacif ic Ocean

- I ron fertil ization in this region wi ll stimulate massive phytoplankton bloom.

Flavodoxin immunofluorescence assay.

The green fluorescence indicates Fe-stressed

diatoms.

(Fe, iron)


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Fe-rich

High-nutrient, low-chlorophyll (HNLC)

Tyrrell, T. & C. S. Law.1997.Nature387: 793-796.

Fe-limited

HNLC


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Boyd, P. W. et al. 2000.Nature407: 695-702.

Iron fertilization experiment


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http://www.whoi.edu/oceanus/

Iron Fertilization Experiments

All 12 reported up to 15-fold increases in the chlorophyll content of surface water.


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Carbon can be captured in the deep sea ?

Perhaps only 1 to 15%

of the original carbon insurface waters sinks

below 500 meters.

~ 200 tons of C sequestered per 1 ton of Fe


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The eruption of Mount Pinatubo, 1991

approximately 40,000 tons of iron dust into the oceans worldwide

global decline in atmospheric CO2and a parallel increase in O2


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Debate on Iron Fertilization (1)

Modern societys last hope to slow global warming

We cannot sure the safety of iron fertilization

* Precautionary principle ()

Not even trying to remedy industrial impacts is far more irres-

ponsible, considering the known pace of increasing harm

This approach may actually sequester very little carbon

per bloom, with most of the plankton being eaten rather

than deposited on the ocean floor


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Debate on Iron Fertilization (2)

Harmful algal bloom

Red tides are largely coastal phenomena

Bloom in the open ocean will dissipate long before

reaching coastal waters

Oxygen depletion in deep waters will threaten

benthic species

Ecosystem alterations: huge impact on fisheries

CO2-induced heating already shifting ecosystems on a

massive scale


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CLAW hypothesis

Charlson et al.1986.Nature326, 655-661.

Charlson, Lovelock, Andreae and Warren
http://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.pnghttp://upload.wikimedia.org/wikipedia/en/f/f5/CLAW_hypothesis_graphic_1_AYool.png


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Anti-CLAW hypothesis

Lovelock.2006. Revenge of Gaia
http://upload.wikimedia.org/wikipedia/en/c/cc/CLAW_hypothesis_graphic_2_AYool.png


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Warming ocean slows phytoplankton growth

Images by Jesse Allen, based on data provided by

Robert O'Malley, Oregon State University


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Warming ocean slows phytoplankton growth

Behrenfeld., M., et al. (2006).Nature,444, 752-755.

NPP : net primary production

SST : sea surface temperature


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Cause & Effect of global warming

Marland, G. et al., 2003."Global, Regional, and National CO2Emissions." http://www.globalwarmingart.com/

1928

2004


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100

Microalgae can do it !


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1. 100

2. 1,

3.

4.

5.

(microalgae)?

Microalgae can be the answer to both of

energy crisisand global warming !


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(Biotechnology Advances 25: 294-306, 2007)

0

10000

20000

30000

40000

50000

60000

(L/ha)

58700(L/ha)

172(L/ha) 446(L/ha)

5950(L/ha)


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1.

.

(Lester Brown):

.

- , 2008. 2.


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There is no magic-bullet fuel crop that

can solve our energy woes without

harming the environment, says virtually

every scientist studying the issue.

But most say that algaesingle-celled

pond scumcomes closer than any other

plantbecause it grows in wastewater,

even seawater, requiring little more thansunlight and carbon dioxide to flourish.

National Geographic (October, 2007)


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Aquatic Species Program (, NREL)

(1978-1996)

3,000

,,

Open pond

,

Dunal iella I sochrysis

: 25-75% 23-37% 25-33%


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Oil

Growth


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: , biofilm ,

Raceway pond:

Helical photobioreactor:

Tubular photobioreactor:


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()

,

Biomass

Biomass

/

CO2

,

+


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Microalgae have the final say

microalgae have the final say

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