L8-phytoplankton,diversity,size,taxa,alage blooms

Question 1

Where do phytoplankton live?

Answer 1

upper, sunlit layers of ocean

Question 2

What is total biomass of phytoplankton?

Answer 2

outweighs that of all marine animals.

Question 3

What proportion of world’s primary productivity is phytoplankton?

Answer 3

40-50%

Question 4

Are phytoplankton monophyletic?

Answer 4

no many different groups

Question 5

How much of phytoplankton is sequestered?

Answer 5

1%

Question 6

How well known is phytoplankton diversity?

Answer 6

not at all very little research on them

Question 7

What are the main phytoplankton phyla?

Answer 7

Cyanobacteria1
Diatoms
Haptophytes (include coccolithophorids)3
Dinoflagellates

Question 8

Eukaryotic phytoplankton belong

to 5 evolutionary lineages

Answer 8

Alveolates

2. Stramenopiles
3. Rhodophyta
4. Green Plants
5. Other Protists

Question 9

How are phytoplankton phyla characterised?

Answer 9

photosynthetic pigments
chloroplast structure
energy reserves
cell wall chemistry
flagella ultrastructure

Question 10

What size is nanoplankton?

Answer 10

2. 0 - 20 um

e. g. Emiliania huxleyi A coccolithophorid

Question 11

What proportion is Nanoplankton?

Answer 11

55% of phytoplankton biomass

Question 12

What size is Picoplankton?

Answer 12

[0.2 - 2.0 m

Question 13

What size is Microplankton?

Answer 13

[20 - 200 m

Question 14

How much of primary productivity are diatoms?

Answer 14

40% marine primary productivity

Question 15

What are diatoms cell walls features?

Answer 15

complex
made of silica
biogeochemical cycling of silica

Question 16

What is diatom Ooze?

Answer 16

When diatoms die they sink to the bottom of the ocean
where they accumulate (1-3 cm/1000 years).
•The slow dissolution of silica and high productivity of
some diatoms lead to the accumulation of oozes.

Question 17

Coccolithophorids Characteristics?

Answer 17

flagella: 2 smooth
haptonema (food capture, attachment organelle)
cell covering of calcareousscales (CaCO3) ‘coccoliths’

Question 18

Emiliania huxleyi (Ehux) features?

Answer 18

• most abundant coccolithophorid - globally
• extremely widespread - most oceans.
• usually outnumbers all other species
combined (can be 80-90%+ phytoplankton)
• many free-floating coccoliths (due to overproduction, death)

Question 19

What forms chalk?

Answer 19

coccolithophorids

Question 20

What are algal blooms?

Answer 20

refer to the overgrowth of macroalgae and/or phytoplankton in response to natural or human-induced changes to the environment.

Question 21

What causes fish kills?

Answer 21

low oxygen due to bacteria feeding on dead algae from algae blooms

Question 22

Why are blue green algae a problem?

Answer 22

massive bloms

Produces hepatotoxins can accumulate

Question 23

What are the main organisms in harmful algae blooms?

Answer 23

Dinoflagellates

Question 24

how much of a bloom are autotrophic?

Answer 24

50% autotrophic

Question 25

When are Harmful algal blooms initiated?

Answer 25

``` higher temperatures (late summer) cause cysts in sediments to germinate ```

Question 26

What favours population growth?

Answer 26

 high irradiance  low salinity  excess nutrients (N & P)  vertical migrations optimise use of light & nutrients  toxins and growth inhibitors inhibit other species  stable water column

Question 27

What will happen to blooming species with climate change?

Answer 27

increase as favoured by higher temp more agricultural runoff hard surface(eg. rodas) cause more runoff

Question 28

How do dead zones form?

Answer 28

``` fresh water brings nutrient input algae bloom algae die and are eaten by bacteria oxygen depleted fish die ```

Question 29

How common are dead zones?

Answer 29

number of Dead Zones in the world’s oceans is increasing dramatically