British Isles Habitat Diversity Flashcards Preview

Biosphere & Man > British Isles Habitat Diversity > Flashcards

Flashcards in British Isles Habitat Diversity Deck (8)
Loading flashcards...
1

Name the varying types of rocks

Igneous
Sedimentary
Metamorphic

2

Define igneous rocks

Includes
- granite - silica rich, nutrient poor, acid soils, well jointed giving craggy terrains and hilltop 'torrs'
- basalt - base-rich, sometimes nutrient rich soils but acid soils if leached by high rainfall, closely spaced joints giving steep cliffs and high plateaux

3

Define sedimentary rocks

Include
- sandstone - dominated by Quartz, may be very nutrient poor giving acid soils or may be calcareous and more base rich
- British formations include lower greensand,mild red sandstone, millstone grit
- clays and shales - dominated by very fine grained clay minerals
- impermeable, low lying land, so poorly drained soils but may be very fertile
- Limestone and chalk - calcium carbonate often gives alkaline soils
- well joined so weathers into caves, ravines, pavements etc

4

What do metamorphic rocks include?

Slate
Mica schist
Gneiss
Quartzite
Marble
Serpentinite

5

Define soil

Non-coherent mineral aggregate
Substrate for most terrestrial life
Two main types
- transported soils (beach and wind loan sands, alluvial sediments, glacial deposits)
- residual soils (developed in-situ by modification of bedrock or transported soils due to reactions with water, air and organisms)

6

Define the British climate

Oceanic
- high rainfall
- high number of rain days
- high precipitation-evapotranspiration ratio
- mild winters
- relatively cool summers

7

What is the precipitation-evapotranspiration ratio?

Considers precipitation and the rate at which water is lost by evaporation or by transpiration through plants
The ratio is affected by total precipitation and temperature

8

Why does Britain show great habitat diversity?

Rocks differ in
- nutrient content
- ease of weathering (nutrient release)
- fragmentation (drainage)
- porosity (water retention)