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Question 1

factors of soil formation (5 factors)

Answer 1

parent material - bedrock/deposits from which soil develops, residual vs. transported

climate - precipitation,evapotrasnpiration determine soil moisture, temperature and moisture influence chemical reaction rate

organisms - bacteria and fungi decompose organisms and nutrients , larger organisms like earthworms or terminates mix aerate the soil

time - slow process disturbance can take centuries to repair

topography - slope and aspect direction affect moisture and temperature , soil erosion on slopes
aspect - downslope direction measured in degrees

Question 2

active energy supplying factors

Answer 2

climate and organisms

Question 3

passive energy receiving factors

Answer 3

topography, parent material and time, cannot form soil without active factors

Question 4

soil profile horizons

Answer 4

horizon - distinct layers of soil that make up the soil profile differing in color, texture and organic content

common horizon - LFH uppermost layer of exclusively organic matter
a - upper layer of minerals and organics
b - mineral layer receives material from above layers
c- actively weathering parent material

Question 5

soil components

Answer 5

Mixture of organic matter and weathered minerals and rocks with variable proportions of air and water, can have distinct layering an dits development is influences by climate and living organisms, supports plant growth

water, air, minerals and organic material

Question 6

soil texture

Answer 6

particles size - sand (2-0.05mm), silt (0.05-0.002mm) clay <0.002mm)

determines propensity, permeability and field capacity

Question 7

field capacity

Answer 7

ability to hold water against gravity

Question 8

soil structure- 4 basic structures

Answer 8

PED naturally occurring clumps of soil
4 basic structures
platy , prismatic, blocky angular and spheroidal granular

Question 9

soil stability

Answer 9

affected by soil texture, parent material and amount of organic material

Question 10

Soil water movement

Answer 10

influenced by soil texture, structure and pore size
sand - water moves quickly , silt and clay - more slowly

water moves in any direction but gravity move sit downward, bedrock may aug eat to move laterally

capillary moves water n unsaturated soils
gravity moves water in saturated soils

Question 11

unsaturated vs saturated soil

Answer 11

Saturated conditions occur when all of the voids, spaces, and cracks are filled with water. Unsaturated conditions occur when the voids, spaces, and cracks between soil, sand, gravel, or rock are filled with a combination of air and water.

Question 12

Canadian soil orders

Answer 12

10 orders in the Canadian system of soil classification

- considers the entire soil profile, specific to Canadian soils and based on soil properties and oil forming processes