Soils Exam 3 Flashcards Preview

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Flashcards in Soils Exam 3 Deck (68):
1

What happens as the biomass of organisms goes down?

The abundance of them goes up

2

Functional Diversity

Utilize a wide variety of substrates and carry out many processes

3

Functional Redundancy

Multiplke species being able to carry out the same function

4

Ecosystem stabability

Soil having several ways to accomplish the same function BY FUNCTIONAL REDUNDANCY

5

Macroorganisms

Greather than 2mm

6

Mesoorgannisms

2-.1mm

7

Microorganisms

Less than .1mm

8

Annelids

Earthworms

9

Helminths

Nematodes

10

Largets biomass in soil

Fungi

11

Actinomcytes

Long strainds and function like fungi but relates to bacteria

12

Protozoa

Mobile single celled and karger than bacteria

13

What is a midden and its function

An eathworm cast that improves soil physical properties

14

What microorganism helps soil horizontally

Ants

15

What helps soil veritcally

Termites

16

H?ow do nematodes benefit and harm soil

They release N from bacteria, but they also bite plant roots to infection

17

What is the function of Protozoa?

They eat Bacteria to release nutrientrs

18

What are the 3 broad groups of fungi?

Yeast Mold Mushroom

19

What separates bacteria from fungi and actinomycetes

Bacteria breaks down material in more anaerobic environments and less complex ,molecules

20

Whyat is a commonesalist

Organisms living side by side with little interaction

21

What decomposes the most complex organic matter?

Actinomycetes

22

What happens to the organic matter during composition

2/3 goes into c02 and 1/3 becomes microbial cells or soil

23

What happens at a high c/n ratio

immobilization

24

What happens at a low c/n ratio

Mineralization

25

What two things does SOM do to improve soil

Increases CEC and pH buffering

26

What 3 residue properties affect decomposition?

Size and surface area
C/n ratio
Chemical composition (lgnin..)

27

For which 2 nutrients are soil tests done?

P and K

28

Ammonia to ammonium

Volizalization

29

What does soil managemenr affect the most

water

30

what nutrient are freshwater systems limited by

p

31

what nutrient are saline water systems limited by

n

32

Name 4 ways to limit nutrient lose in agri

buffer strips
cover crops
conservation tillage
forest stand management

33

soil minerals supply little amount of this nutrient

N

34

What ratio is higher in manure than plant tissue

P:N

35

what 4 factors influence mineralization

moisture
aeration
temperature
C:N rstio

36

where does the majority of po and k come from?

geologic deposits

37

where can k fert be found

salt beds

38

from where is n fertilizer extracted

the atmosphere via the haber bosch process

39

what are 3 hazards associated with inorganic fert use

salt hazards, acid formation, volatilization

40

how do you know how much n to add to soil

expected crop yield, soil type

41

what does freeze/thaw affect in soil

k availability

42

what is the first step of mineralization

ammonification

43

what is the second step of mineralization

nitrfication

44

What does a high C:N ratio cause GREATER THAN 30:1

immobilization

45

what does low C:N cause LESS THAN 20:1

mineralization

46

What can caude volitalizarion?

high pH
little moisture

47

is nitrate readily leached

yes?

48

what is the reduction ofn to a gaseous form

denirtification

49

what occurs to nirtogen in anaerobic conditions

denitrification

50

what can cause redness and short roots

P deficiency

51

what major nutrient is scarce in soil

P

52

what helps plants uptake p

mycorrhizae

53

what happens when C:P ratios are less than 200:1

mineralization

54

what happens when P concentration is greater than 300:1

immobilization

55

what type of p is unavailable as pH increases

calcium phosphates

56

what type of p is less soluble at lo pH

hydroxy phosphates

57

where is most k held in soils

feldspars and micas that make it unavailable

58

what is throughfall

k taken up by plants then washed away by raineater from plant foliage

59

what is the problem with k

there is a large amount present, but only little available and plants intake it luxuriously

60

what nutrient is measured by its rate of transformation than total amount in soil

K

61

how do we limit k uptake in plants

watch the soil pH levels

62

what organism has greatest biomass in soil

fungi

63

what is the smallest pool of P

soil solution

64

what are the 2 most common ways to lose SOM

erosion and decomp

65

what organism ahs the greatest number in soil

bacteria

66

what 3 propeties affect decomp

chemical content, zie, C:N ratio

67

what process adds most nitrogen to soil

biological nitrogen fixation

68

what is the symbiotic relationship between roots and fungi

mycorhizzae