Lecture 7 CM

Question 1

Desert

Answer 1

(look at slides)
- 20-40 degrees N&S

Question 2

Dry Tropical Forest/Scrub/Savanna

Answer 2

(look at slides)
- 0-30 degrees N&S
- more than any other biome, dry tropical forests and savanna are in a constant state of change
- fires are common in the long dry season
- in Africa and India, elephant grazing is a key driver of habitat change

Question 3

What do seasonal fires and grazing of herbivores in the Dry Tropical Forest/Scrub/Savanna result in?

Answer 3

it results in a continual shifting of forest habitats across the landscape in what is known as a shifting mosaic

Question 4

Dry Tropical Forest/Scrub/Savanna features

Answer 4

(look at slides)
- riverbank habitats are more fixed features of the landscape
- elephant foraging path destroys trees
- the absence of fire and grazing allows new forests to establish
-new forest margin appears
- wildfire effects the margin of the forest
- reduced grazing allows forests to develop
- new forest margin appears

Question 5

Savanna has the greatest…

Answer 5

• greatest vertebrate biomass of any biome
• supported by a surge in soft leaf tissue production by tropical grass species after seasonal monsoon rains
• seasonal shifts in monsoon winds trigger mass herbivore migrations from dry grasslands to wet grasslands

Question 6

Carnivores in the dry tropical forest are generally…

Answer 6

more territorial and less mobile

Question 7

Grasses in the dry tropical are…

Answer 7

much more tolerant

Question 8

Where do forests dominate in the dry tropical forest?

Answer 8

they dominate only where grazing and fire are reduced however, patterns at any one point in time are liable to change

Question 9

Tropical rainforest

Answer 9

(look at slides)
- 0-20 degrees N&S

Question 10

The Mountain Zone

Answer 10

(look at slides)
- high altitude habitats exist in every biome
- the elevational ecological gradient is similar to the latitudinal climate gradient, but over a much shorter interval
- individual mountain ranges contain multiole biomes, up to and including permanent ice cover
- species endemism is higher in mountain areas because habitats are very restricted in area and usually surrounded by very different vegetation
- mountain habitats are more susceptible to disturbance/destruction and the effects of climate change compared to lowland areas

Question 11

The mountain ranges in the mountain zone comprise…

Answer 11

comprises a series of sub-biomes at different altitudes e.g the North American Rocky Mountains