Lecture 14 Biogeochemcial Cycling Flashcards
Who are the major players in biogeochemical cycles?
- Phytoplankton
- Zooplankton
- Nekton
- Microorganisms
What are the 4 fates of sinking particles?
- Respiration by attached microbes
- Respiration by free-living microbes
3 Enzymatic dissolution/microbial disaggregation - Zooplankton
What are the four steps of sampling suspended and sinking particles with the Marine Snow Catcher?
- Filtration
- DNA extraction
- PCR
- Illumina sequencing
Out of suspended and sinking, which one has the highest unique diversity
Suspended
What are r-strategy
- Opportunists
- Sinking particles
- Labile organic matter
What are k-strategy?
- Specialists
- Semi-labile organic matter
- Suspended particles
What influence microbial communities in the dark ocean?
Surface productivity and community structure
How does the microbial pump sequester C?
- Microbial processing of DOM generates less labile DOM
2. In time, DOM becomes more refractory and accumulates in the dark ocean
What do viral infections do?
- Restructure microbial community
2. Accelerate C cycling within microbial loop
What causes niche partitioning between sinking and suspended particles?
Organic matte lability
What is ammonia oxidation?
A two-step oxidative process, involving ammonia monooxygenase (AMO) and hydroxylamine oxidoreductase (HAO) and a terminal oxidase
Who performs anammox?
A group of chemolithoautotrophic bacteria that belong to plactomycetales
How are nitrification and anammox linked?
NO2- is produced in nirification and is required as a substrate in anammox
What is nitrate reduction
Usually considered the first step in denitrification, but is also a standalone process, responsible for large nitrate accumulation
