Knowledge checks

Question 1

In the color 10 YR 5/6 Which is which

Answer 1

Hue- 10YR
Value- 5
Chroma -6

Question 2

What means the darkest in the munsell system

Answer 2

Lower value

Question 3

What does soil aeration have the greatest effect on?

Answer 3

sand

Question 4

What does water erosion potential have the greatest effect on?

Answer 4

silt

Question 5

Best water holding capacity

Answer 5

Clay

Question 6

True or false? as the average particle size increases, the surface area also increases

Answer 6

false

Question 7

Root growth is typically inhibited in loamy soils when bulk density is above

Answer 7

1.6

Question 8

Important mechanisms for soil aggregation

Answer 8

-earthworm “castings”
-clay and divalent or trivalent bridging
-polysaccharides or globulin produced by soil microorganisms
-root hair networks

Question 9

What pore sizes would have limited air exchange be primarily filled with water that is available to plants?

Answer 9

micropores

Question 10

True or false: a soil with a higher ratio of micropores compared to micropores will have greater infiltration than one with more micropores

Answer 10

false

Question 11

true or false: overtime tillage generally decreases total porosity and increase the ratio of micropores to micropores in the soil

Answer 11

true

Question 12

What force creates surface tension of water

Answer 12

Cohesive force

Question 13

Which soil texture would you expect water to rise highest by capillary movemnt

Answer 13

Clay loam/Clay

Question 14

A soil tensiometer is a method to measure

Answer 14

Soil water potential

Question 15

Oven-drying a soil sample at 105C is a method to measure

Answer 15

gravimetric water content

Question 16

Darcy’s law is used to describe:

Answer 16

water movement in saturated soil

Question 17

The maximum amount of water soil can hold that is useful to plants is termed:

Answer 17

field capacity

Question 18

What is the soil water potential associated with the following soil moisture terms? Hydroscopic

Answer 18

-3100 kPa

Question 19

What is the soil water potential associated with the following soil moisture terms? Maximum retentive capacity?

Answer 19

0 kPa

Question 20

What is the soil water potential associated with the following soil moisture terms? Permanent wilting point?

Answer 20

-1500 kPa

Question 21

What is the soil water potential associated with the following soil moisture terms? Field capacity?

Answer 21

-10 kPa

Question 22

Plant-available water refers to:

Answer 22

the amount of water between field capacity and wilting point