1. World Geography 3202
Unit 3
Ecosystems

2. The general characteristics of a given ecosystem
All life forms seem to be specially suited to the physical characteristics of the ecosystem that they inhabit.
The one feature that is most essential for identifying a given ecosystem is its climax vegetation – The chief vegetation that has developed in a region over a long period of time, given a particular climate.
the general characteristics of a given ecosystem

3. The general characteristics of a given ecosystem
Analyze patterns in the distribution of world ecosystems

4. The general characteristics of a given ecosystem
Analyze patterns in the distribution of world ecosystems

5. The general characteristics of a given ecosystem
Analyze patterns in the distribution of world ecosystems
Predict which kind of ecosystem is likely to result from a stated set of climatic conditions

6. The factors that affect soil quality :
Soil develops from a complex interaction of several processes occurring over centuries.
the factors that affect soil quality

7. The quality of a soil in terms of its soil texture
Soil quality or fertility is measured in terms of a soil’s hums content relative to the amount of ground-down bedrock it contains.
The key factor that causes variance in soil profiles is climate
Climate provides the moisture needed for the weathering process at the beginning of soil formation, as well as the precipitation and dry heat needed for leaching, eluviations and capillary action to occur.
Analyze the quality of a soil in terms of its soil texture

8. The quality of a soil in terms of its soil texture
A key component in determining a soil’s value is its texture.
Texture refers to the types of particles in the soil
Both particle size and the extent to which particles bond to one another affect soil quality.
These characteristics of particles determine how much water will flow through the soil, the water holding capacity of the soil, and air movement through the soil.
Analyze the quality of a soil in terms of its soil texture

9. The quality of a soil in terms of its soil texture
The three smallest components, Sand, Silt, and Clay, are the principal components of soil.
At one extreme, Sandy soil, is loose and coarse. Water and air penetrate easily, making for easy drainage and rapid warming. It is so loose, however, that moisture needed for large scale plant growth is not retained.
The other extreme is clay soil, which consists of fine grains of silicate material containing aluminum and water. This tends to hold water like a sponge and does not permit air to pass through. The soil is slow to warm up, slow to drain and hard to work.
Analyze the quality of a soil in terms of its soil texture

10. The quality of a soil in terms of its soil texture
The most desirable soil texture for farmers is a balanced combination of soil, clay and silt particles, forming loam.
Analyze the quality of a soil in terms of its soil texture

11. Global patterns related to soil loss
Draw conclusions about global patterns related to soil loss.

12. Global patterns related to soil loss
Certain regions enjoy more fertile soil than others.
However all regions are subject to soil degradation
Soil can be degraded or lost in a very short period of time
The most common cause of soil loss is water run-off.
Other factors include urban expansion, overgrazing, flooding, and deforestation
Desertification: The degradation of land into arid and semi arid states through careless land use such as overgrazing.
Draw conclusions about global patterns related to soil loss.

13. Global patterns related to soil loss
Based on this chart, where is the loss of soil the greatest? The least?
Draw conclusions about global patterns related to soil loss.

14. Global patterns related to soil loss
Draw conclusions about global patterns related to soil loss. See pp

15. Assess statements about soil availability
In Africa Only 16 per cent of the land is suitable for farming
In Southern Asia Only 20 per cent of the land is suitable for farming
In Central and Northern Asia Only 10 per cent of the land is suitable for farming
In Europe a fairly large amount of the soil is suited to farming
Assess statements about soil availability