Midterm

Question 1

Which horizon ID has illuviation?

Answer 1

Bt

Question 2

What does the horizon suffix ‘m’ mean?

Answer 2

change in colour or texture or both

Question 3

What soil structure does Bm have?

Answer 3

blocky or prismatic

Question 4

What does the horizon Bmk tell us?

Answer 4

partial removal of carbonates

Question 5

Decalcification?

Answer 5

acid reaction that removes carbonates from a horizon

Question 6

Calcification?

Answer 6

Secondary carbonates. deposition of carbonates transported down from upper horizon (Cca)

Question 7

Salinization?

Answer 7

accumulation of soluble salts

Question 8

Glacial till PM

Answer 8

LETHBRIDGE AREA. transported by glaciers, tilling the land. hummocky, LOAMY medium textured. coarse fragments. loam, sandy loam, clay loam, sandy clay loam

Question 9

Glacio fluvial

Answer 9

CHIN AREA. transported by flowing water glacial melt. high sand content. slight sloping

Question 10

What is a shelter belt?

Answer 10

use of trees to break wind. caragana plant

Question 11

Glacio lacustrine

Answer 11

COALDALE. lake water stagnant. undulating and flat level. clay textured. rarely coarse fragments.

Question 12

Lethbridge typical soil profile?

Answer 12

Ah, Bm, Ck

Question 13

What does the suffix n tell us?

Answer 13

high in sodium. columnar

Question 14

The darker the soil zone on the prairies is a factor of?

Answer 14

amount of precipitation, highest precip in black, lowest in brown

Question 15

What 2 nutrients are immobile?

Answer 15

phosphorus and potassium

Question 16

Which 2 nutrients are mobile?

Answer 16

nitrate and sulfate

Question 17

Best cation to form aggregates?

Answer 17

Ca

Question 18

Cation most likely to cause clay dispersion?

Answer 18

Na

Question 19

Why is a dispersing agent (calgon aka sodium hexametaphosphate) added to soil prior to determining soil texture?

Answer 19

completely separates the particles

Question 20

Which particles settle after 40 seconds?

Answer 20

sand

Question 21

Which particles settle after 2 hours?

Answer 21

silt

Question 22

Which particles never settle?

Answer 22

clay

Question 23

Why is it necessary to correct hydrometer reading?

Answer 23

• addition of dispersing agent
• change in temp

Question 24

What horizon sequence is typical of luvisolic areas?

Answer 24

Ae, Bt, Ck

Question 25

Regional influence on soil?

Answer 25

Climate

Question 26

Local influence on soil?

Answer 26

topography

Question 27

What is flocculation?

Answer 27

the same as aggregation

Question 28

What is bulk density?

Answer 28

weight of soil divided by volume

Question 29

what is particle density?

Answer 29

mass per unit of volume

Question 30

What is soil porosity?

Answer 30

the nonsolid volume of soil

Question 31

Relationship between bulk density and porosity?

Answer 31

Inversely related. as bulk density increases, porosity decreases.

Question 32

What is the influence of compaction on bulk density?

Answer 32

increases the bulk density and decreases porosity

Question 33

How does organic matter influence bulk density?

Answer 33

high OM decreases the bulk density and increases pore space.

Question 34

Which texture of soil makes a ribbon stronger than 5 cm?

Answer 34

clayey textured soils

Question 35

Which textured soil makes a ribbon less than 2.5 cm?

Answer 35

sandy