Geography 2

How do the changes to vegetation occur?

Land clearing and the planting of monocrops

How does land-clearing effect vegetation?

Forests that are cleared for farm land lead to deforestation. The grazing animals on the farms then cause damage to the forests undergrowth.

How does the planting of monocrops effect vegetation?

• Reduces vegetation variety, which therefore doesn’t return the correct nutrients to the soil and makes it less fertile

• The pesticides and herbicides used to grow the crops damage and kill native flora and fauna

• Soil that is exposed due to land clearing becomes vulnerable to erosion

What are the changes to water due to human alteration?

Water pollution, dams and irrigation

How does water pollution effect the water?

Water pollution, such as leached herbicides and pesticides, causes algal blooms, which produce dangerous toxins which can damage and kill aquatic animal and plants, as well as terrestrial animals that rely on the water for hydration.'

What is desertification?

The process of a region gradually become drier, losing bodies of water, vegetation and wildlife.

How does desertification occur

• Overuse of grazing

• Farming

• Land clearing

What does desertification increase?

Increased:

• Sandstorms

• Crop losses

• Famine

• Conflict

• Loss of plant and wildlife

What are the changes to soil due to human alteration?

• Salinity

• Soil degregation

• Terracing

What are the effects of increased salinity?

• Destroys plant life

• Rising water tables

• Collections of salt in the soil

How does an increase in salinity occur?

• Removing plants from water with deep roots

How does soil degregation occur?

• Depleted soil nutrients/non-firtile soil

• Soil erosion

• Herbicides and Pesticides

What does terracing do?

Changes the shape of the land to make it more productive

What does terracing lead to?

• Rain saturation

• Erosion

Terrestrial Biomes

Biomes found on land

Aquatic biomes

Biomes found in water

Polar lands

Very cold and dry. They have little animal life and almost no vegetation.

Tundra

Cold, with short growing seasons and no trees.

Boreal Forest

• Cold and wet

• Filled with coniferous trees

• 300-900mm of rain annually (depends of location)

• Ranges from -40c to 20c

• Average summer temp of 10c

• Long cold winters with snow

• Well defined seasons

• Humid summers

Threats to Boreal Forests

• Loss of trees for wood and paper

• Forest clearing for oil and gas

• Insect plagues

• Acid rain

• Bushfires

• Deforestation

• Climate change causes the tundra to be replaced by forests

Temperate forests

Mild temperatures and wet weather, with lots of trees and animal life. Located in the bottoms of Eurasia and North America and someimes along the coasts of other continents

Mountain vegetation

Found on cold and windy land and is adapted so that it won’t be blown over.

Grasslands

• Vegetation that reach 20cm to 2.1m

• 500-900mm of annual rain

• Can reach extreme temps

• Ranges between -20c and 30c

• Open and continuous

• Fairly flat

Deserts

Very dry and almost no plant life. Often located in the centre of continents, away from coasts.

Tropical forests

Warm and wet with lots of diverse plant and animal life Found along the equator.

Freshwater biomes

Low/no levels of salinity, support some aquatic animal and plant life.

Marine biomes

Made up of three zones that get colder and darker as the water gets deeper. Most marine life exists closer to the surface.

Coral reefs

Found in warm waters closer to the lands. Filled with coral and animal life that depends on it.

Shrubland

• Filled with dense, low-growing shrubs and small trees

• Hot, dry summers and mild, wet winters

• Supports a diverse range of wildlife due to the vegetation that grows there

Threats to grasslands

• Habitat loss due to agriculture, urbanization and infrastructure development

• Overgrazing by livestock

• Invasive species

• Climate change increases drought conditions and can lead to severe floods or dry spells