Algal Diversity Flashcards
Why are algae important?
As much NPP as land, Base of marine food web, role in cycling elements, locking away carbon
Marine microalgae applications
Industrial: biofuel, fatty acids, pigments…
Marine microalgae problems
Toxic
places where macroalgae can grow
Attached to rocks, coastal, free-floating
Microalgae size range
0.5 micrometer - > 1000 micrometer
Microalgae life styles
Autotrophic, mixotrophic, heterotrophic
Autotroph
An autotroph is an organism that can convert abiotic sources of energy into energy stored in organic compounds,
Mixotrophic
photsynthesize like plants and hunt like animals
Heterotrophic
use organic carbon as food source
Planktonic microalgae are
phytoplankton
Femtoplankton 0.02-0.2 micrometer
Virioplankton
Picoplankton 0.2-2 micrometer
Bacterioplankton, phytoplankton
Nanoplankton 2-20 micrometer
Mycoplankton, phytoplankton
Microplankton 20-220 micrometer
Phytoplankton
Marine cyanobacteria size
Picoplankton, colony/chain nano/micro
Diatoms size
Nano, micro, colony/chain meso, macro
Haptophyceae size
Nano, colony/chain micro
Dinoflagellates size
Nano, micro
chl containing phytoplankton
Cyanobacteria, diatoms, mixoplankton
Grazers, protozooplankton: life style + which ones
mixoplankton, ciliates, dinoflagellates
Diatoms, latin name
Bacillariophyceae
Life style diatoms
Autotrophic
Diatom cell wall
Silicified
Productivity diatoms depends on
Silicic acid
Centric subgroup species
Mostly pelagic, Blooms in eutrophic systems, silicified cell walls, require silicic acid
Pennate subgroup species
Silicic acid cell walls, dominate benthic communities, have raphe
Raphe
Gliding movement by expulsion of gelatinous poly saccharides
Fragilariineae
no raphe
Bacillariineae
Have raphe
Benthic microalgae function
Top 3 cm of sediment, Colour sediment brown, stabilize sediment particles
Auxospore formation
Critical size, adverse environmental conditions
marine cyanobacteria are
Photosynthetic prokaryotes
Prokaryote
Single-cell organism which lacks a nucleus and other membrane bound organelles
Cyanobacteria size
0.3 micrometer - 1 mm, picophytoplankton
Cyanobacteria area
Dominant in tropical (oligotrophic) oceans
Life style cyanobacteria
Autotrophs
Adaptations to nutrient limitation
Nitrogen fixation, become very small, streamlined genomes, become closely associated with microbial loop, survive with minimal resources
Prochlorococcus ecotypes
Different ecotypes as a function of depth
Richelia
Nitrogen fixing symbionts of diatoms
Diazotrophs
Nitrogen fixers
Flagellates
Same ground plan
Life styles flagellates
Autotrophic, mixotrophic, heterotrophic
Flagellate cell walls
Naked, cellulose, calcium carbonate, cellulose and silica
Haptophyceae: prymnesiophyceae examples
Emiliania huxleyi, Phaeocystis spp
Haptophyceae: prymnesiophyceae size
5-10 micrometer
Subgroup haptophyceae
coccolithophores
Coccolithophores outer housing
CaCo3
Coccolithophores outer housing function
Protection against grazing, virus and light modulation
2 life-cycle stages coccolithophorids
Holococcolith and heterococcolith
Large grazers
Small colonies
Small grazers
Large colonies
Naked dinoflagellate
Athecate
Cellulose plates
Thecate
Lifestyle dinophyceae
Autotrophic (50%), heterotrophic, mixotrophic, free living, parasitic
Toxic dinoflagellates
Harmful algal blooms
Phagocytosis
Engulf prey
Peduncle feeding
Attach straw and suck out prey
Pallium feeding
Digest in a sack
Organic carbon produced by phytoplankton
> 80% passes through foodweb and microbial loop
Fate of carbon of nano and picophytoplankton
Carbon recycled in days by bacteria in surface ocean
Fate of carbon of larger cells
Consumed by grazers, through fecal pellets carbon isolated in deep ocean
Storage time of carbon depends on
How deep it enters the ocean
POC
Particulate Organic Carbon
POC aspects
> 0.7 micrometer, aggregated cells, debris, bacteria, fecal pellets
POC export efficiency depends on
size, composition, particle shape
DOC
Dissolved Organic Carbon
DOC aspects
<0.7 micrometer, excreted by phytoplankton, product of grazing, viral lysis
DOC
feeds microbial loop