10. Black Earth

Question 1

What’s significant about coal in comparison to other rocks?

Answer 1

Coal is the only combustible rock

Question 2

From what era are coal bearing rocks most prevalent?

Answer 2

Upper Carboniferous

Question 3

Does upper mean earlier or later in reference to time periods?

Answer 3

Later (closer to present)

Question 4

What is the significance of most continents being clustered on the equator in the carboniferous period?

Answer 4

Extensive tropical climates

Question 5

What difference is there is prevalence of plants between the Silurian and late Devonian/Carboniferous?

Answer 5

Plants were scarce during silurian, but becoming abundant on land from late devonian

Question 6

During what era do plants appear on land?

Answer 6

Paleozoic

Question 7

What makes a plant vascular?

Answer 7

The presence of xylem as a mechanism for transportation within the plants stems

Question 8

What new attribute of plants first developed around the Permian period?

Answer 8

Seeds

Question 9

What new attribute of plants first developed around the Carboniferous period?

Answer 9

Early vascular systems in plants

Question 10

What are Charophyceae?

Answer 10

Fresh water green algae, closest ancient relative of land plants today!

Question 11

What are the oldest group of extant vascular plants?

Answer 11

Lycophytes

Question 12

What are lycophytes?

Answer 12

oldest extant group of vascular plants, i.e. first vascular plants

Question 13

What two types (genuses?) of plant had developed before the carboniferous?

Answer 13

Charophyceae, Bryophytes

Question 14

What defines Bryophytes?

Answer 14

• First land plants but still very tied to water
• Only some had stomata

Question 15

What group of plants originated around the end Carboniferous and dominated for >200My?

Answer 15

Gymnosperms

Question 16

What are the defining features of gymnosperms?

Answer 16

• Seeds
  Still dominate in high-latitude regions

Question 17

What 4 groups are included in gymnosperms?

Answer 17

Cycads, ginkgoes, gnetophytes, conifers

Question 18

What are angiosperms? When did they develop?

Answer 18

Flowering plants
- During the mesozoic

Question 19

What are the four main environments plants adapted to live in?

Answer 19

Dry, streamside, wet, disturbed

Question 20

What environmental conditions led to the best preserved plants?

Answer 20

Swampy ground

Question 21

What process is referred to as the ‘Palaeozoic apartheid’?

Answer 21

The process by which different taxonomic groups of plants would adapt for different environments and stay largely separated.

Question 22

What are lycopsids?

Answer 22

Water and fire resistant plants with thick bark

Question 23

What is a common feature of preserved lycopsids?

Answer 23

Preserved with a hollow centre as that rots away and the thick, strong bark is preserved

Question 24

What is most coal composed of?

Answer 24

Bark of swamp lycopsids

Question 25

What cyclical cycle reinforced coal production in tropical swamps?

Answer 25

• Sea levels would rise over a tree rich region, creating a layer of sediment over coal seams.
• When this water recedes, new swampy conditions give rise to more trees and coal
• Sea levels rise again etc

Question 26

What two things are heavily involved in our current cycles of decomposition?

Answer 26

Detritovores and decomposers

Question 27

How do detritovores and decomposers work together?

Answer 27

Detritovores ‘chop up’ dead matter, decomposers then decompose this

Question 28

What are 2 broad examples of decomposers?

Answer 28

Fungi, bacteria

Question 29

Why is so much coal made of swamp lycopsids?

Answer 29

Bark is made of lignin, which is very hard to break down

Question 30

What is one diversity based reason why so much more coal was produced in the carboniferous period?

Answer 30

No/significantly less wood-eating detritovores

Question 31

What 3 data results suggest slower decomposition in the Carboniferous period?

Answer 31

• More big bits relative to small bits in peat
• More leaves relative to roots in peat
• More undecomposed leaves

Question 32

What is the significance of slower decomposition in the carboniferous period?

Answer 32

More time for dead matter to become coal

Question 33

What is the significance of detritovore bore hole size in the Carboniferous?

Answer 33

Up to 40 times smaller, harder to break down matter then

Question 34

What is the 4 step coal process of the carboniferous?

Answer 34

1) Trees with thick and decay resistant bark fall into still swamp water.
2) Few shredders and borers or detritovores to decompose them.
3) Rotting uses up oxygen in the swamp and creates an anoxic environment .
4) The anoxic environment hampers bacteria and fungi processes.

Question 35

How does the ‘coal machine’ of the carboniferous increase oxygen levels?

Answer 35

• Lignin contains lots of C but not much Phosphorus.
• C is taken out the system by coal, but phosphorus is not really
• P Continues to fuel productivity on land and bury more carbon.
• Oxygen can rise as C levels drop

Question 36

What negative feedback loop maintained oxygen levels in the Paleozoic and Mesozoic as lower than they could’ve been?

Answer 36

Forest fires destroying/hampering oxygen producing plants

Question 37

Why did more forest fires take place after the carboniferous? What evidence do we have?

Answer 37

Higher oxygen levels increase probability of flash fires
- Charcoal is common from this era

Question 38

What can CO2 reduction in the last 45My be mostly attributed to?

Answer 38

Increased mountain uplift and weathering