L7: Microbial Biomes Flashcards
What are the parameters for diversity of soil
spatially, temporally
Explain each soil parameter
- spatially: heterogenous
- pockets of different nutrients, minerals + particles with different arrangments
- temporally: heterogenous
- sunlight, water, temp
- opp for diverse organisms
Describe a biome with specific headings
O2: Aeorbic if wet, aneorbic if wet?
ED+EA: metals, carbons
C source: decaying biomass, CO2
Sunlight: YES/NO
What are patters in soil microbial diversity
- alpha highest at warm + warm areas
- alpha lowest in cold or dry areas
Where do most cells live
- most live 10cm below the surface
- the surface is more disturbed
- deepest: less carbon input
What are most soil microogranisms and why
- heterotrophs
- plant primary production produces so much carbon than any microbe
- the plant also reduce amount of sunlight in ground
- so hard for the light eaters (photosythesiors)
- however, no plants ⇒ autotrophs (cus no nothing)
Describe soil + rhizosphere gradient
- rhizosphere: everyone uses the same electron, carbon, energy sources
- high biomass + activity
- lower diversity (cus everyone is eating the same, those who eat different are out competed)
- Detrisusphere
- dead litter
- Bulk soil
- greater diversity of e-, carbon + energy source
- lower microbial biomass
- higher diversity cause food is so different
What are trends in rhizosphere
- moving away from root
- diverity up
- biomass + activity down
- r strategist fast growth rate to k stategist low growth rate
- pathogens increase: cause rizhzophere microbes outcompete pathogens and have really nice vibes going
What are endophytes
bacteria living in plant root
What do fungai come from
form mycorrhizal associations with plants
Desrcibe the attraction between bacteria and rhizosphere
- r attracted to plant by signalling components + root nodules
What is Rhizobium symbiosis
- N fixing root nodules in legumes give plant ammonia
- plant gives nodules carbon
What is Phyllosphere
total above ground surface of the plant
- more limited than soil = less diverse
- survive by secreting hormons, biosurfacts, pigments to protect
What is in the deep surface
chemolithotrophs
use WoodL (not energy intensive)
Marine Microbial habitats
- has different characteristic zones
- temportally homogenous within zones
Go through each marine zone microbial diversity
Photic
* O2: yes
* ED: C compounds, water, some dissolved metals
* EA: O2, nitrate, sulfate
* C source: Limited, necromasses
* Sun: yes
* Nutrients: nah
Aphotic
* O2: limited
* ED: C compunds, water, dissolved metals
* EA: nitrate, sulfate
* C: limited, necromasses
* Sun: No
* Nutrien: nah
Ozygen minimum
* O2: no
* ED: C compounds, metals, dissolved metals
* EA: O2, Nitrate, Sulfate
* C source: necromasses
* Sun: yes
* Nutrients: nah
Trends in microbial marine diversity
- species richness increases with depth even though less cells
- beta diversity: more or less the same, decreases with depth (same same)
- functional richness: increases with depth
What are pelagibacterales
ruler of ocean
most succesful clase of organisms on earth
* hetetrophic, low nutrient, small (high SA:V), small genome
Discuss marine food web
c courses: CO2, DOC, water
high molecular weight can only be degraded with extracellular enzymes
cells die become DOC
hetreophs breathe and procde CO2
What is the phycosphere
- mucus rich region surrounging phytoplankton cells
- immediate environemnt around is oxygen + organic rich
- lower diverity but higher activity
- includes nitrogen fixing bac
Characterisitics of oxygen minimum zones
- too deep for photosyntheisis = no oxygen
- eutrophic nutrient rich conditions = hetropthic activity = O consumed
- limited lateral ocean movment = no oxygen coming
chemolithoautotrophs
Freshwater habitats
not as homogenous as ocean
Sediment microbial communities
soil/water intermediate
- minerals + C source
- waterlogged = homogenised effect
O2: at surface
ED: metals, carbon
EA: metals, sulfate
C couse: necromass
Sun: maybe
nutrint: depends
