Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Glaciology > L8 & 9 - Glacier Microbiology & Biogeochemistry > Flashcards

L8 & 9 - Glacier Microbiology & Biogeochemistry Flashcards

1
Q

Give 6 ways that we can use glacier microbiology work?

A
  1. Helps us understand how life evolved
  2. Predict how life might operate on other planets
  3. Understand snowball earth and past global glaciation life survival
  4. Understand extreme environments using biotechnology
  5. Find out how glacier melt impacts downstream systems
  6. Understand how organisms change glacial systems (albedo)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Until when were glaciers thought to be sterile?

A

~30 years ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Give 2 pieces of evidence we have for glacial life

A
  1. Watermelon snow in the Alps

2. Chemical imbalances in meltwaters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does life need to survive?

A

Water & Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What must be considered when looking at water in the cryosphere?

A

Thermal Regime

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Microorganisms can extract nutrients from rock/debris – True or False

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where does life reside?

A

Primarily the supra and sub glacial environments but there is also some in the englacial environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What species of algae is present on snow and what colour pigmentation does it have?

A

Chlorophota chlamydomonas

Green & Pink/Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do the pigments on snow algae protect them against?

A

UV and Freeze-Thaw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What impact do the pigments on snow algae have on albedo?

A

It lowers it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are ice algae resistant to?

A

Low Temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does ice algae look like?

A

Dirt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does ice algae do to the ice sheet surface?

A

It causes a Darkening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a Cryoconite Hole?

A

A self-contained, unique habitat made up of ice, water and sediment along with windblown or avalanched debris and microorganisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What role does the Ice Lid play for a Cryoconite Hole?

A

It provides protection from hostile conditions and creates an isolated stable environment, in which light can still penetrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Give 4 points about Antarctic Cyroconite Holes

A
  1. Stable Community
  2. May be isolated from the drainage system for decades
  3. pH 11!
  4. May be sealed off from the atmosphere for years at a time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give 3 points about Arctic Cyroconite Holes

A
  1. Ice lids melt out and the hole remains stable during flushing
  2. Remain connected to the drainage system and the atmosphere
  3. Sediments and microbes bind to form granules from EPS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How can supraglacial channels and ponds host life?

A

Debris = micro-organisms and nutrients which = energy which = life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is an EPS?

A

Extra Polymer Substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Supraglacial channels and ponds are well studied - True or False?

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the main sources of water and energy in the subglacial environment?

A

Debris, Lakes and Channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

At the glacier bed, there is a lot of debris and minimal light, what are the 2 main types of specialist organisms that live there?

A
  1. Chemoautotrophs

2. Chemolithoautotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is there evidence of debris in climate records?

A

Debris bands in polar ice cores

24
Q

Who found that there are active microbes at the bed that require electrons acceptors via REDOX reactions?

A

Skidmore et al., 2000

25
Q

Give 6 energy sources in the subglacial environment

A
  1. REDOX Tower
  2. Ammonia (NH4)
  3. Pyrite (FeS2)
  4. Sulphate Reduction
  5. Methanogenesis and anaerobic methanogens
  6. Rock Crushing (Source of H+)
26
Q

What 2 things help microorganisms in the subglacial environment?

A
  1. Summer Melt

2. Rock Grinding

27
Q

What is Blood Falls and what may its research be helpful for?

A

A subglacial outflow with rusting processes and carbon cycling and microorganisms that have adapted to survive using the REDOX process. May be helpful on Europa

28
Q

Where can the subglacial environment get nutrients from? (With Citation)

A

The surface and the rocks

Boetius et al., 2015

29
Q

Give 3 facts about subglacial lakes

A
  1. There is liquid water at the bed of the ice sheets (up to 3-5km down)
  2. They are geothermal hotspots
  3. There are over 350 in Antarctica, with this number rising annually
30
Q

How do subglacial lakes exist?

A

Ice at the bed is at the p.m.p due to a geothermal heat flux, there must be suitable topography which gives a depression allowing meltwater to collect and for ice to flow over the top. Insulation for the water acts as feedback mechanisms whilst sealing the lake off from the atmosphere. Temperature fusion pressure alters the p.m.p.

31
Q

Is there liquid all year-round in subglacial lakes?

A

Yes

32
Q

Give 2 methods of finding subglacial lakes

A
  1. Satellite Imagery

2. Sounding

33
Q

What does a radar return of a subglacial look like?

A

It is flat

34
Q

Who has studied Lake Vostok?

A

The Russians

35
Q

Who has studied Lake Whillains?

A

The USA

36
Q

Who has studied Lake Ellsworth?

A

The UK

37
Q

How big was the ice core taken from Lake Vostok?

A

4km

38
Q

What is the biggest subglacial lake under Antarctica?

A

Lake Vostok

39
Q

What was the problem with the samples taken from Lake Vostok?

A

Contaminated by drill fluid and anti-freeze

40
Q

Where does AI 1 occur?

A

In the embayment

41
Q

Where does AI 2 occur?

A

In the open lake

42
Q

How are microbes present in Lake Vostok?

A

From refrozen accretion ice

43
Q

What is an inclusion?

A

A mineral particle to which dirt is attached and traded on refreezing

44
Q

What is Meteoric Ice?

A

Refreezing onto ice above the lake

45
Q

What is rate of accretion at Lake Vostok?

A

2-6cm/year

46
Q

At what end of Lake Vostok is there accretion?

A

Southern End

47
Q

Give 4 pieces of evidence for accretion ice

A
  1. Crystal Size
  2. No gas trapped between the crystals
  3. Isotopes
  4. High EC
48
Q

What was found at Lake Whillains?

A

Cycle based use of ammonia from dead organisms and a diverse ecosystem

49
Q

Why did the Lake Ellsworth study end with no samples?

A

Technical difficulties and a challenging environment

50
Q

Give 2 methods of drilling cleanly and which is only good for geomicrobiology and not climate science

A
  1. Hot Water Drilling

2. UV Sterilised Water (not good for climate science)

51
Q

Under which lake were fish found?

A

Lake Whillains

52
Q

Where is life found in Englacial Habitats?

A

In the solute rich veins in between crystals

53
Q

How have organisms in the glacial environment adapted?

A

Anti-freeze proteins and desiccation

54
Q

Give 5 reasons why we are interested in glacial life?

A
  1. Climate Amplifier
  2. Ocean Fertilisers
  3. Ice Albedo Feedback
  4. Biotechnology
  5. Astrobiology
55
Q

What must organisms in the englacial environment be adapted to?

A

Living without Oxygen

Glaciology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions