Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AGRI 51 > chapter 4c > Flashcards

chapter 4c Flashcards

1
Q

more H+ ions

A

pH low (acidic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

more OH+ ions

A

pH high (alkalinity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

negative logarithm of the total hydrogen ion concentration in the solution

A

pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

acidity or alkalinity, due to relative concentration of H+ and OH ions

A

pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

humid
arid
inorganic

A

5 to 7
7 to 9
4 to 10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

relationship between pH and %BS

A

linear relationship

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

as pH increases

A

H+ decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

method by pH meter, more accurate

A

electrometric method

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

organic dyes, litmus paper (ex: cornell pH)

A

colorimetric method

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

soil test kit

A

nitrogen, phosphorus, and potassium. next is lime requirement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

effects of soil pH on microbial act

A

fungi: unaffected
bacteria & actinomycetes: inhibited at pH 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

(1) origin of soil acidity

A

release of hydrogen atoms under natural chemical processes in the soil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

rel of H under natural chem

A

*atmospheric carbon dioxide reacts w/ water to form carbonic acid
*organic molecules reacts w/ water and causes acid dissociation
*oxidation of ammonium nitrogen, sulfur, and iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

(2) origins of soil acidity

A

accumulation of OM and subsequent release of products of decomposition: fulvic and humic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

(3) origins of soil acidity

A

reaction of aluminum cations with water, “hydrolysis”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

(4) origins of soil acidity

A

natural deposition
- lightning deposits nitric acid
- volcanic activity deposits sulfuric acid
- mineral weathering: Pyrite or Fool’s Gold (FeS2) once oxidized, results to formation of acid sulfate soils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

(5) origins of soil acidity

A

human factors
- oxidation of applied synthetic ammonium-based fertilizer
-oxidation of nitrogen compounds in applied animal manure or sewage
- deposition of acid rain (nitric and sulfuric caused by industrialization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

forms of soil acidity

A

active acidity: due to H+ in soil solution, determined as pH
reserve acidity: due to H+ and Al+++ in the solid phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

ability of soil to resist sudden/drastic changes in pH

A

buffering capacity

20
Q

measure of the buffering capacity of soil

A

reserve and active acidity

21
Q

buffering capacity is high if

A

CEC is high
clay content is high
OM content is high

22
Q

production constraints associated with acid soils

A

aluminum toxicity- usually damages the root system first
mn toxicity- less common than Al toxicity
nutrient deficiency- P, Ca, and Mo deficiency (also nitrogen)

23
Q

(4-5) production constraints with acid soils

A

restricted microbial activities: mineralization of organic N, biological fixation of N
incidence of plant diseases: some plants are more likely to be affected by damping off (fungal disease) and root rot in acid soils

24
Q

(1) management strategy

A

reduce acidification
- minimize use of acidifying fertilizer
- reduce leaching of N by use of split applications of fertilizer
- return plant material to soil

25
Q

(2) management strategy

A

used acid-tolerant crops
- sweet potato, coffee, radish, tomato, pineapple, strawberry, irish potato

26
Q

(3-4) management strategy

A

apply more nutrients
apply agricultural lime

27
Q

only means of correcting soil acidity

A

lime

28
Q

any oxide, hydroxide, or carbonate of Ca or Mg used to neutralize soil acidity

A

lime

29
Q

carbonate form

A

CaCo3 (calcitic limestone)
CaMg(Co3)2 dolomitic limestone

30
Q

oxide and hydroxide form

A

CaO (burned lime)
Ca(OH)2 hydrated lime

31
Q

depends on soil

A

pH: lower- more lime
exchangeable Al- more, more lime
texture- clayey, more lime
OM- depeds

31
Q

amount of lime depends on soil

A

pH: lower- more lime
exchangeable Al- more, more lime
texture- clayey, more lime
OM- depends

32
Q

amount of lime depends on (2)

A

type and variety of crops to be grown

33
Q

amount of lime depends on (3)

A

kind of lime
- fineness
- chemical guarantee

34
Q

amount of lime depends on (4)

A

economic return from lime application

35
Q

amount of salt that have accumulated in the soil

A

salinity

36
Q

expressions of chemical guarantee of lime

A

oxide content in %CaO r %MgO
calcium oxide equivalent- strength in pure CaO
calcium carbonate equivalent (neutralizing power)- CaCo3

37
Q

high osmotic potential

A

low salt concentration

38
Q

low osmotic potential

A

high salt concentration

39
Q

excess Na causes

A

disperse and swell, affect drainage, aeration, and root penetration. toxicity to plants

40
Q

ability of substance to conduct electric current

A

electrical conductivity

41
Q

ability of an electrolytic solution to conduct electric current

A

electrical conductivity

42
Q

index of total ionic concentration in solution

A

electrical conductivity

43
Q

more saline

A

higher EC

44
Q

correct salinity

A

irrigation water

45
Q

correct sodicity

A

gypsum or sulfur

AGRI 51 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions