EGS Pippin 1. Intro to Biome concept.

Question 1

Overview???

• (), an American ecologist, is sometimes described as the () of the ().
• He focused on how () is ().
• He noted the way plants & animals are () in () across () & () -> developed ()
• () is a () way of looking @ any community to understand what () are () () in that community.

Answer 1

• Robert Whittaker, an American ecologist, is sometimes described as the Godfather of the Biome conept
• He focused on how the diversity of life is distributed.
• He noted the way plants & animals are distributed in particular ways across space & time -> developed Gradient Analysis
• Gradient Analysis is a linear way of looking @ any community to understand what factors are driving composition in that community.

Question 2

Scientists involved in defining the biome concept

(1). ():
* Point:
* Point:

(2). ():
* Point:
* Point:

(3). ():
* Point:

(4). ().
* Point:

Answer 2

(1). Robert J. Whittaker:
* Defined biomes as large-scale ecological communities w. distinct climate, veg. & animal life
* Know for work on ecological gradients in biomes

(2). Clements (1916):
* First
* Defined biome as a community of plants & animals that occupy a specific geographic area &
* are characterized by distinct climatic conditions

(3). Tansley (1935):
* introduced the term ‘ecosystem’’
* biotic and abiotic factors (soil)

(4) Shelford & Clements (1939):
* further work

Question 3

Why are biomes useful units?

Answer 3

Means of predicting environmental control of distribution of life
(understanding the mechanisms behind patterns of distribution)

Question 4

Biomes defined P1/3

• (1) Biomes are () that () major () over (), defined by (), typically (), over () of ().
• (2) While the definition of Biomes has (), they are generally recognised as the () @ the (), mappable at a scale ().
• (3) This scale offers a () view, where () & () areas can be distinguished.

Answer 4

• (1) Biomes are large ecological units that represent major life zones over extensive areas, defined by dominant life forms, typically plants, over long periods of time.
• (2) While the definition of biomes has evolved over time, they are generally recognized as the largest land units @ the continental scale, mappable at a scale no larger than 1:10 Ma
• (3) This scale offers a broad, homogenous view, where typical & less typical areas can be distinguished.

Question 5

Biomes Defined P2/3

• (4) Biomes are () based on the (), with () made according to ().
• (5) They are (), not ().
• (6) At (), biomes are understood (), driven by () dominant plant cover, with () and () playing secondary roles.

Answer 5

• (4) Biomes are primarily classified based on the dominant plant cover, with secondary distinctions made according to climatic features that most influence the biota.
• They are natural systems, not anthropogenic.
• At macro-scale, biomes are understood mechanistically, driven by factors that determine dominant plant cover, with climate and soil playing secondary roles

Question 6

Biomes defined P3/3

• (7) With (), such as () & more detailed () like (), () or (), providing further distinctions.
• (8) Despite attempts to simplify, the study of biomes ().

Answer 6

• With functional plant traits, such as macro-growth forms & more detailed ecological characteristics like photosynthetic pathways (C3, C4, CAM), succulence, or sclerophylly, providing further distinctions.
• Despite attempts to simplify, the study of biomes remains complex

Question 7

Usefulness of Raunkiaer’s Life Form Scheme?

2 points

Answer 7

• Pulls attention away from fixation on specific species → focus on mechanisms of being a specific plant form → understand why they grow where they do.
• They can be understood in relation to their structure, their function, their similarities or dissimilarities in form & function in a way that allows us to understand the factors that allow for growth

Question 8

Raunkiaer’s Life Form Scheme P1:

(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)

Just name them

Answer 8

• 1. Phanerophytes
• 2. Chamaephytes
• 3. Hemicryptophyes
• 4. Cryptophytes/Geophytes
• 5. Hydrophytes
• 6. Epiphytes
• 7. Therophytes
• 8. Aerophytes

Question 9

Raunkiaer’s Life Form Scheme P2:

• (1). Phanerophytes:
• (2). Chamaephytes:
• (3). Hemicryptophytes:
• (4). Cryptophytes/Geophytes:

Answer 9

• (1). Phanerophytes - woody trees, perennial, projecting stems into the air (oak).
• (2) Chamaephytes - woody shrubs w. stems closer to ground (lavender) .
• (3) Hemicryptophytes - smaller, herbaceous plants, biennial or perennial, but near soil (dandelion).
• (4) Cryptophytes/Geophytes - have below ground storage mechanisms (bulbs) (March lilies).

Question 10

Raunkiaer’s Life Form Scheme P3:

• (5). Hydrophytes:
• (6). Epiphytes:
• (7). Therophytes:
• (8). Aerophytes:

Answer 10

• (5) Hydrophytes - grow completely submerged in water (water lillies)
• (6) Epiphytes - don’t require soil, but grow on plant (orchids)
• (7) Therophytes - annual, opportunistic plants, ruderals, rapid life cycles, lots of seeds (Namaqua Daisies).
• (8) Aerophytes - air plants

Question 11

Why do we use the 3 photosynthetic pathways?

Answer 11

Way of looking @ landscape full of plants & asking can we draw boundaries anywhere based on how these plants assimilate CO2 & solar energy

Question 12

The 3 Photosynthetic Pathways:
(1)
(2)
(3)

Answer 12

1. C3 pathway
2. C4 pathway
3. CAM (crassulacean acid metabolism)

Question 13

The 3 Photosynthetic Pathways P1/3

(1) C3 pathway:

• Point 1:
• Point 2:
• Point 3:
• Point 4:
• Point 5:

1. First P; 2. Optimal; _ system; commonality; e.g.s

Answer 13

• First Product = 3-carbon acid
• Optimal @ high CO2 & low temps.
• Older system
• Most common
• Wheat, rice, sunflowers, grass

Question 14

The 3 Photosynthetic Pathways P2/3

(2) C4 pathway:

• Point 1:
• Point 2:
• Point 3:
• Point 4:
• Point 5:

1. First P; 2. Optimal; 3. _ system; 4. commonality; 5. e.g.s

Answer 14

• First Product = 4-carbon acid
• Optimal @ low CO2 & high temps.
• More recent evolutionary system
• Smaller group 3%
• Maize, sugar cane, sorghum, cabbages

Question 15

The 3 Photosynthetic Pathways P3/3

• CAM (crassulacean acid metabolism):
• Point 1:
• Point 2:
• Point 3:

Answer 15

• Take up energy during the day but only uses it at night
• So they can keep their stomata closed ->
• Water saving, common in arid regions

Question 16

Effect of Climate Change on Biomes:

• () has gone up and down over the years - ()
• We are () our models in terms of ().
• Some plants may () with higher CO2 levels while others will () with increasing temperatures:
  
  • () favours CO2
  • () favours temp
• We have complex models; but ultimately ().

Answer 16

• Carbon has gone up & down over the years - ice core data
• We are outstripping our models in terms of CO2 release.
• Some plants may thrive with higher CO2 levels while others will struggle with increasing temperatures:
  
  • C3 favours CO2
  • C4 favours temp
• We have complex models; but ultimately not really sure what will happen long term.