Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Greenhouse Gas Emissions > Greenhouse Gas Emissions > Flashcards

Greenhouse Gas Emissions Flashcards

1
Q

What are the most common green house gases? (3)

A

Carbon Dioxide (CO2), Methane (CH4), Nitrous Oxide (N2O)

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

Soil carbon pool?

A

~1500Pg

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

Soil Nitrogen Pool?

A

~140Pg total nitrogen

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

What is the largest store of terrestrial organic Carbon?

A

Soil is the largest store of terrestrial Organic Carbon with ~1500Pg tonnes

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

How does carbon go into the soil?

A

The decomposition of leaf litter that falls of trees and the roots of trees is the majority

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

What are the two types of carbon?

A

Organic and Inorganic carbon

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

Examples of Inorganic Carbon.

A

Calcium Carbonates

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

Examples of Organic Carbon

A

Sugars and Lichens

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

What respires in the soil?

A

Roots and microbes

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

What is the total soil respiration for plant roots?

A

Approximately 50% but can range between 10-95% depending on the season and vegetation type

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

What is the NEE?

A

Net Ecosystem Exchange- the difference between the ecosystem respiration and photosynthesis

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

What is a Positive NEE?

A

When respiration is greater than photosynthesis

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

What is a Negative NEE?

A

When photosynthesis is greater than respiration (carbon sink)

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

What can change the input of carbon into the soil?

A

The climate and type of land use

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

Two types of carbon input in soil?

A

Above ground and below ground

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

Examples of above-ground carbon inputs.

A

Annual leaf litter fall, timer fall in the forest and animal residues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Examples of below-ground carbon inputs.

A

Plant roots, dead roots, carbon compounds releasing from living roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where are carbon rich soils?

A

Grassland areas as carbon is sequestered via the roots

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

What causes soil respiration?

A

Decomposition

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

What is soil respiration?

A

When carbon dioxide and methane are released during the process of decomposition

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

What is DOC? Why is it significant?

A

Dissolved Organic Carbon. It is released into rivers and rivers due to soil erosion

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

How much Carbon is emitted back into the atmosphere?

A

60-80%

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

What are the three organisms?

A

Macro-organisms
Meso organism
Microorganisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Examples, size, and role of macro-organisms.

A

> 2mm
Larger animals such as moles and rabbits, earthworms, ants and insects.
They mix fresh organic material into the soil and bring organic matter into contact with soil microorganisms.
Allows microbes to access all parts of the organic residue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Examples, size and role of Meso Organisms.
2-0.2mm Mites, nematodes Feed on microorganisms and release nutrients contained in their bodies
26
Examples, size and role of microorganisms.
<0.2mm Bacteria, fungi and algae Responsible for the production of enzymes catalysing SOM decomposition reactions and are important for Nitrogen fixing and denitrifying
27
Name four bacteria types.
Autotrophs Heterotrophs Aerobes Anaerobes
28
What are Autotrophs?
Bacteria and all algae that synthesise their cell substance from CO2 and energy from the sunlight
29
What are Heterotrophs?
Many species of bacteria and all fungi that require carbon in the form of organic molecules for growth
30
What are Aerobs?
They are active in unsaturated soils and require oxygen- the end product of respiration CO2 and release essential nutrients such as nitrogen
31
What are anaerobes? | End product
Active in absence of oxygen in saturated soils- the end product of respiration methane and carbon dioxide. Very slow decomposition
32
Nitrogen Cycle
33
What are the three forms of nitrogen?
NO3- nitrate NH4+- ammonium Organic Nitrogen
34
Functions of NO3-
It is the preferred form of nitrogen nutrition for most species of plants. It is highly soluble in water. If nitrate is not assimilated by plants or microorganisms, it is leached from soils.
35
Functions of NH4+
Plants are adapted to acidic soils and can utilise ammonium as their source of nitrogen nutrition, although most non-acidic soils can only utilise nitrate. It is soluble in water and attracted to negatively charges surfaces associated with clays and organic matter in soil. Not as mobile as nitrate
36
Organic Nitrogen and examples
Nitrogen containing molecules. Amino acids, proteins and humic substances
37
Gaseous forms of Nitrogen (6)
``` N2 atmospheric dinitrogen gas NO Nitric Oxide NO2- Nitrogen dioxide N2O- Nitrous oxide NH3 Ammonia ```
38
What is N2?
Atmospheric dinitrogen gas
39
What is NO?
A gas emitted to the atmosphere mostly as a result of combustions
40
What is N2O?
Nitrous oxide- dentrification occurring in wet nitrate rich soils
41
What is NH3?
Ammonia- usually occurs as a gas, vapour or liquid
42
Why is nitrogen important for plants and farming?
They require nitrogen for photosynthesis. Increased Nitrogen inputs can lead to more food produced to feed more people- known as the green revolution
43
How is nitrogen deficiency addressed?
By applying a form of nitrogen fertiliser
44
Examples of nitrogen fertiliser
Compost (plant waste) or manure (animal waste)
45
Why do soils rich in organic matter not require fertiliser?
Organic matter decomposes and releases NH4+ (ammonium) and NO3- (nitrate)
46
Why is too much nitrogen in soil bad?
It can be harmful to plants as it can prevent plants from flowering and producing fruit (plant burn). Excess nitrate often leaches into the groundwater and causes excess growth of algae (eutrophication)
47
How can nitrous oxide be emitted to the atmosphere?
The action of anaerobic bacteria of inorganic fertiliser or organic animal manure applied to the soil
48
What are temperature drivers of GHG emissions from the soil? (4)
Radiation Exposure (soil cover) Soil Colour (mineralogy) Wildfires
49
What are humidity drivers of GHG emissions from soils? (3)
Soil water content Water filled space Precipitation/drought (intensity and frequency)
50
What are land cover drivers of GHG emissions from soils?
Transformation | Ecosystem Resilience
51
What are land cover drivers of GHG emissions from soils?
Forestlands, grasslands, barrenlands, croplands, wetlands
52
What are vegetation type drivers of GHG emissions from soils?
Age and type Distribution Leaf Area Index
53
How can temperature affect GHG emissions?
Increases decomposition rates with temperature
54
How can water affect GHG emission rates?
Soil moisture- not too try and not too wet- CO2 emission | Air and oxygen- more O2 higher decomposition
55
What is methantrophy?
CH4 oxidation- the uptake from the atmosphere (uplands, forest, soil)
56
Where is methane produced?
Anaerobic conditions (wetlands and rice fields)
57
What is the C:N ratio?
The ratio of the mass of carbon to the mass of nitrogen in a substance
58
Purpose of carbon and nitrogen for microbes.
Carbon is the source of energy and Nitrogen is the source of protein
59
What happens if the ratio of C:N is >25?
There is not enough Nitrogen for microbial activity- microbes take nitrogen from plant supply or decay is delayed
60
What happens if the C:N ration is 24?
This is the most favourable for microorganisms as they have to maintain their own C:N ratio to 8:1
61
What happens if the C:N ration is <24?
Microbes will consume the material and leave excess nitrogen in the soil for plants or other microbes
62
What happens when peatlands are drained?
Mass amounts of CO2 will be released into the atmosphere
63
What do wetlands release and absorb?
Releases Carbon Dioxide and Methane and absorbs Carbon Dioxide
64
What gases do peatlands emit and absorb?
Emits Carbon Dioxide and Methane and absorbs Carbon Dioxide
65
What gases do pasture emit and absorb?
Emits carbon dioxide, methane and nitrous oxide and absorbs carbon dioxide
66
What gases to arable lands emit and absorb?
Emits carbon dioxide and nitrous oxide and absorbs carbon dioxide
67
What gases do grasslands emit and absorb?
Emits and absorbs carbon dioxide
68
What gases do forest emit and absorb?
Emits carbon dioxide and absorbs carbon dioxide and methane
69
What is soil respiration important?
soil respiration is part of the natural carbon cycle and it is a necessary process to release plant available nutrients into the soil
70
Is all co2 produced in soil emitted?
No. Some is stored in small pores until rainfall events that will replace the soil-air with water
71
Why is it important to increase the input of carbon into the soil?
So more carbon is absorbed from the atmosphere by plants than emitted to the atmosphere form soils
72
How is methane produced in soil?
During aerobic decomposition of organic matter content together with CO2
73
What are methanogens?
Bacteria responsible for the production of CH4
74
What is the process of methane by methanogens called?
Methanogenesis
75
Where is methane production typical?
Waterlogged soils such as peatlands and wetlands
76
What can utilise methane?
Methanotrophic bacteria in oxic layers located above waterlogged soils It can be uptakes directly from the atmosphere

Greenhouse Gas Emissions (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions