BI303 - Section 1 Lecture 5

What is the dominant vegetation type inthe Arctic Tundra?

Herbs, bryophytes, low growing shrubs

What type of soil is found in the Arctic Tundra?

Peaty, waterlogged soil

Polar cell

The polar cell is formed by subsidence of cold air at the poles and by exchange of energy between equatorial and polar air masses at the polar front.

Ferrell cell

The Ferrell cell is driven by the movement of the Hadley and polar cells. Over temperate regions.

Hadley cell

The Hadley cell is formed by the uplift of warm air at the equator. Over tropics.

What are the 9 principal terrestrial biomes?

1. Arctic Tundra
2. Boreal Forest/ Taiga
3. Temperate Deciduous Forest
4. Temperate evergreen forest
5. Temperate shrubland/ mediterranean scrub
6. Temperate grassland/ steppe
7. Desert
8. Tropical seasonal forest/ savanna (Sub-tropical)
9. Tropical rainforest
10. Mountain Biome

What varies across different biomes regarding human activity?

The footprint or impact of this activity

Where does the Arctic Tundra occur?

Above 60 degrees N and S of the equator

What is the soil condition in the Arctic Tundra?

Soil water remains frozen for 7-8 months

What is the hight of vegetation in the Arctic Tundra?

Less than 1 meter tall

What is a key feature of the Arctic and Boreal Biomes?

Permafrost (permanently frozen ground)

What is the dominant vegetation type in the Boreal Forest?

Conical evergreen coniferous trees and deciduous trees

What are examples of coniferous trees in the Boreal Forest?

Spruce, Pine, Fir

What is the climate like in the Boreal Forest?

Freezing winters, mild summers

What is the average net annual productivity of the Boreal Forest?

2250 Kcal m-2 yr-1

What advantage does the conical tree shape provide in the Boreal Forest?

Minimises exposure and transpiration stress

How does the vertical orientation of canopy limbs benefit trees in the Boreal Forest?

Improves efficiency of energy capture

What is the dominant vegeation type in the Temperate Deciduous Forest?

Deciduous trees

What is the average height of vegetation in the Temperate Deciduous Forest?

30 meters tall

What is the rainfall in the Temperate Deciduous Forest?

More than 80 cm per annum

What is the net annual productivity of the Temperate Deciduous Forest?

4500 Kcal m-2 yr-1

What adaptation do deciduous woody plants have for winter?

Bud-enclosed meristem protects from freezing

When do leaves and flowers form in deciduous trees?

In autumn, expand in Spring and Summer, nothing in Winter

What is the flowering cycle of D. cucullaria in temperate forests?

Completes before light is lost in early May

What is the dominant vegetation type in the Temperate Evergreen Forest?

Giant, canopy forming species

What is the average height of the canopy in the Temperate Evergreen Forest?

Greater than or equal to 120 meters high

What is the rainfall in the Temperate Evergreen Forest?

40-400 cm per annum

What is the net annual productivity of the Temperate Evergreen Forest?

6000 Kcal m-2 yr-1

What is the dominant vegetation type in the Temperate Shrubland?

Drought-tolerant shrubs and trees

What is the climate in the Temperate Shrubland?

Hot summer, mild winter

What is the average net annual productivity of the Temperate Shrubland?

3600 Kcal m-2 yr-1

What is the dominant vegetation type in Temperate Grassland?

Fire, drough, and cold-tolerant grasses

What is the climate in Temperate Grasslands?

Warm summer, cold winter

What is the average net annual productivity of Temperate Grasslands?

2250 Kcal m-2 yr-1

How do apical meristems affect plant resilience in grasslands?

Apical meristems at ground level enhance recovery after disturbances.
Aboveground meristems are more vulnerable to damage.

How do grasses regenerate after fire or grazing?

Grasses regenerate quickly, but trees and shrubs are often destroyed

What impact does the position of apical meristems have on habitats?

It affects resilience to physical disturbances

What are the characteristics of tropical grasslands?

Similar resilience strategies as temperate grasslands.
Adaptations to cope with fire and grazing.