Exam 2

Question 1

0 bars

Answer 1

Saturation

Question 2

-1/3 bars

Answer 2

Feild Capacity

Question 3

-15 bars

Answer 3

Permanent Wilting Point

Question 4

-31 bars

Answer 4

Hygroscopic Coefficient

Question 5

-10,000 bars

Answer 5

Oven Dry

Question 6

Leaching of anions out of the soil

Answer 6

Lower

Question 7

Acid Precipitation

Answer 7

Lower

Question 8

Nutrient Uptake

Answer 8

Lower

Question 9

Decomposition of plant residues

Answer 9

Raise

Question 10

Nitrogen fertilization

Answer 10

Lower

Question 11

Adding Lime

Answer 11

Raise

Question 12

Recycling of basic cations by deep rooted plants

Answer 12

Raise

Question 13

Water classification where evaporation stops and the soil is said to be air-dry.

Answer 13

Hygroscopic Coefficient

Question 14

Which of the water potential values indicates water that is held most tightly to soil?

Answer 14

-3100 kPa

Question 15

Which increases evapotranspiration?

Answer 15

Increasing wind

Question 16

Which of the following is NOT a device that measures soil moisture?

Answer 16

pressure plate apparatus

Question 17

Which force moves free water in the soil out of the macropores?

Answer 17

gravitational

Question 18

Irrigation can lead to the build up of too much

Answer 18

Nitrogen

Question 19

Which of the following textural classes holds the least amount of PAW?

Answer 19

Sand

Question 20

The water classification where drainage stops because the matric potential balances the gravitational pull and the macropores are empty is called:

Answer 20

Field Capacity

Question 21

The movement of free water is dependent on the amount and continuity of

Answer 21

Macropores

Question 22

This type of water is energetically available to plants (plants have enough energy to use it) but is NOT useable by plants because no oxygen is present.

Answer 22

Free/Gravitational water

Question 23

How should a sandy soil be watered vs. a clay soil?

Answer 23

Sandy Soil more often with less water each time

Question 24

Plant available water depends on or is a function of the soil’s _______________ and ____________ _____________ content.

Answer 24

Texture, Organic Matter

Question 25

Bonding of water to another water molecule is called:

Answer 25

cohesion

Question 26

Evapotranspiration is the loss of water by evaporation from the soil and transpiration through plant leaves.

Answer 26

True

Question 27

Which of the following irrigation methods is the LEAST efficient in conserving water?

Answer 27

Flood

Question 28

A portion of this water is energetically not availabe to plants.

Answer 28

Capillary Water

Question 29

Bonding of water to the soil surface is called:

Answer 29

Adhesion

Question 30

Is water held from -15 to -10,000 bar plant available?

Answer 30

No, Not Energetically Available

Question 31

The entry of water downward through the soil surface is called:

Answer 31

infiltration

Question 32

The attraction between water and soil surfaces is described by which component of water potential?

Answer 32

Matric

Question 33

Is water held from 0 to -1/3 bar plant available?

Answer 33

No, No Oxygen

Question 34

All of this water is energetically not available to plants (plants do not have enough energy to use it).

Answer 34

Hygroscopic Water

Question 35

How should a sandy soil be watered vs. a clay soil?

Answer 35

Sandy Soil more often with less water each time

Question 36

Cation exchange is an example of an

Answer 36

Adsorption process

Question 37

The surface charge of most clays is negative.

Answer 37

True

Question 38

The cation exchange sites (surfaces) of soil clays adsorb negatively charged particles.

Answer 38

False

Question 39

CEC is the abbreviation for:

Answer 39

Cation Exchange Capacity

Question 40

Which soil horizon would have the lowest CEC?

Answer 40

C

Question 41

Attraction of ions to surface solids is the definition of

Answer 41

adsorption

Question 42

check the four properties that cation exchange controls in soil

Answer 42

buffering of soil pH, leaching of cations, nutrient adsorption by plants, soil weathering

Question 43

Which soil particle has the highest CEC?

Answer 43

Humus

Question 44

The humus content in the soil is dependent on:

Answer 44

all of these answers influence humus content in soil

Question 45

Colloidal properties are exhibited by which soil size separate:

Answer 45

Clay

Question 46

Anion exchange occurs in some tropical areas and is when the soil is positively (+) charged and attracts negatively (-) charged ions called anions.

Answer 46

True

Question 47

Normal range on pH scale:

Answer 47

0-14

Question 48

Neutral soils

Answer 48

7 PH

Question 49

Acid/Acidic PH

Answer 49

0 to 7

Question 50

Basic PH

Answer 50

7 to 14

Question 51

Which of the following is a cation?

Answer 51

K+

Question 52

Cation Exchange Capacity is measured in

Answer 52

meq/ 100g