Chapter 5: SOILS ( 8 questions )

Question 1

What does the soil matrix consist of? Give specific percentages for the pie chart.

Answer 1

It consists of: - 5% organic matter - 45% small soil and mineral particles - 25% water - 25% air

Question 2

Why are desert soils low in organic matter?

Answer 2

Desert soils are low in organic matter due to high temperatures. High temp means low rain fall and keeps many plants from putting organic matter in soil.

Question 3

How does chemical weathering differ from physical weathering?

Answer 3

Chemical weathering involves water that’s slightly acidic. As it falls on mineral matter it weathers it down and causes changes by chemical reaction. Physical weathering is caused by natural occurrences like earthquakes, erosion, or wind.

Question 4

Explain why air and water in the soil matrix are considered to be dynamic(always changing).

Answer 4

Air and water space are always changing because water space is filled with air and soil can again become saturated with water.

Question 5

What are the 3 soil separates?

Answer 5

Sand, silt, and clay are the 3 soil separates. They are found in most soils.

Question 6

What is the charge of a clay particle?

Answer 6

The charge of a clay particle is slightly negative.

Question 7

What determines soil texture?

Answer 7

The materials that make up soil make up soil texture. Those being either silt, clay, course sand.

Question 8

What are the 5 soil-forming factors?

Answer 8

The five soil forming factors are: - Parent Material - Time - Climate - Vegetation - Topography