UMI ZAKIYAHFaculty of Fisheries and Marine Science - UB

*MARINE CLIMATE

CHANGE :’ IMPACT AND

RESPONSES OF

PLANKTON ‘

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*WHAT ARE PLANKTON/ PHYTOPLANKTON?

*WHERE ARE THEIR HABITAT?

*WHAT ARE THEIR ROLE IN MARINE ENVIRONMENT?

*WHY THEY ARE IMPORTANT?

*WHAT HAPPEN TO THEM? WHAT IS EXPECTED?

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*The word plankton is from the Greek word

for "wandering" They are unicelluler and

some multicelluler organism (0.2 um - >20

m) that drift or wander on the surface of

the oceans at the mercy of the currents.

They are generally unable to move against

currents (MARE: Marine

Activities, Resources & Education - NASA).

*Plankton community are primarily divided intobroad functional (or trophic level) groups:

1. Phytoplankton

2. Zooplankton

3. Bacterioplankton

OR

1. Producer

2. Consumer and

3. Recycler groups

Phytoplankton (from Greek phyton, or

plant), autotrophic, prokaryotic or

eukaryotic algae that live near the

water surface where there is

sufficient light to support

photosynthesis. Among the more

important groups are the diatoms,

cyanobacteria, dinoflagellates and

coccolithophores.

*The 7 algae divisions are:

1. Chlorophyta (Green algae)

2. Charophyta (Stoneworts or brittleworts)

3. Euglenophyta (Euglenoids)

4. Chrysophyta (Golden-brown algae,Diatoms)

5. Phaeophycophyta (Brown algae, kelp)

6. Rhodophyta (Red algae)

7. Pyrrhophyta (Dinoflagellates)

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MARINE ENVIRONMENT

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*An estimated 90% of all photosynthesis and production of usable oxygen takes place in the oceans (MARE, 1995). Marine phytoplankton are the first link in the large marine food chain. Larger animals like fish and the blue whale then consume the zooplankton, which feeds on the phytoplankton. The food material from living and dying plankton may sink to the bottom and become food for organisms living on the bottom.

*About 90% of the world’s fisheries occur in rich coastal areas because of the high densities of plankton that grow in areas with many nutrients in the water. The high protein content of plankton is causing them to be considered as a potential food source for people. There is also discussions about using phytoplankton in space missions. The personnel would give the plankton carbon dioxide and it would in turn give oxygen and a food source to the people ("Plankton", 497).

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*Increase in average

temperatures

*Extreme weather vents

*Shift in climate patterns

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* The increase in water temperatures

significantly affect the limits of

phytoplankton growth rates: populations

near the equator have the potential to

grow much faster than strains found in

cooler waters, near the poles, given

sufficient nutrients.

*The oceans vary much less than the

land does, both seasonally and daily

*Increased temperature decreases

viscosity, but increase metabolism

rate

*Organisms grow faster, die younger

as temperature increases

*In general, warm water species are

smaller and have more extensions

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* They analysed phytoplankton data

collected over 76 years by previous studies

(published between 1935 and 2011), and

also used future temperature predictions

generated by climate scientists. 194 strains

of phytoplankton belonging to over 130

species from the major groups were

analysed

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* The results suggest that by the end of the 21st century, warmer oceans will lead to a greater diversity of plankton populations nearer the poles, but fewer varieties in warmer, tropical waters at the equator.

* Even though marine organisms can disperse over long distances carried by ocean currents, each plankton strain grows best at an optimum temperature and adapts to its local environment.

* Tropical strains appear to be most vulnerable to rising temperatures.

* a third of current strains in the tropics would become extinct by 2100 if mean temperatures increase by just 2°C. However, high genetic diversity within species may prevent the loss of entire species.

* Rising temperatures will thus affect phytoplankton in different ways, depending on their location.

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*United Nations Framework Convention On Climate

Change. World-wide electronic

publication, http://www.unfccc.int; accessed on 02

November 2006. [Web]

*Beardall, J; & Raven, J.A. 2004. The potential effects

of global climate change on microalgal

photosynthesis, growth and ecology. Phycologia. 43 (1)

26-40.