Brainscape's Knowledge GenomeTM

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


See full index

ECOL 1001 > lec 10 soils > Flashcards

lec 10 soils Flashcards

1
Q

why learn about soil?

A

-allows to make better decisions on plant materials

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

– “ of soil has been created since the glaciation

A

8-10 “

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

what is soil/ earth

A

-material that constitutes the outermost solid layer of the planet

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

what is def’n of soil?

A

naturally occurring mixture of inorganic and organic ingredients with a definite form, structure and composition

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

what is average soil ingredients?

A

45% mineral matter
25% water
25% air
5% organic matter or humus

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

why are compacted soil bad?

A

removes air space which removes air space giving less ability for organic matter to live

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

how is soil formed

A

by interaction of the earth’s crust with atm and biological influences through combination of 5 factors

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

what are 5 soil forming factors

A
  1. parent material
  2. regional climate
  3. topography
  4. biotic potential
  5. time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is parent material

A

earth material; both mineral and organic

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

describe role of regional climate in soil formation

A

parent material is broken down into finer particles via weathering- controlled by climate of location
-temp and water major climatic forces

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

describe topography

A

-hilliness, flatness or amount of slope of the land

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

describe biotic potential/ organisms in formation of soil

A

-plants and animals help create soil via decomposition and disturbance via digging

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

t or f; true soil is a mass of mineral particles

A

false; influenced, modified, and supplemented by living organisms

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

what is humus

A
  • semi- soluble chemical (biochemical) substance

- produced via decomposition of organic matter into by fungi and bacteria

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

what do soil organisms such as earthworms, beetles and termites do for soil ?

A

vertically redistribute humus within the mineral matter found beneath surface of soil

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

what are 3 benefits of humus

A
  1. enhances a soils ability to hold and store moisture
  2. primary source of carbon and nitrogen req’d by plants
  3. improves soil structure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the layers of soil called . why are they formed

A
  • horizons
  • integrated effects of climate and biosphere change
  • becomes less pronounced with depth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is a soil profile?

A

-vertical cross- section view of soil

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

what 4 horizons are noted in soil profile ?

A
  1. o= organic
  2. a= topsoil
  3. b= subsoil
  4. c= parent material
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does the organic layer consist of

A

-fragments of leaf litter, twigs, roots, and other organic material lying on surface of soil at various levels of decomposition and humus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

t or f; organic layer is not present in cultivated fields

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is found in the topsoil layer ?

A
  • humus and other organic material mixed with mineral particles
  • zone of translocation which illluviation has removed finer particles and soluble substances to a lower layer
  • dark in colour, light texture and porous
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the most productive soil layer?

A

top soil

24
Q

what are characteristics of subsoil?

A
  • light coloured, dense and low organic matter
  • strongly influenced by illuviation ; receives materials from A
  • may be coloured by oxides of irons and aluminum or by calcium carbonate
25
Q

describe the parent material layer

A

unconsolidated organic and mineral in which soil forms

-largely uninfluenced

26
Q

what layer would you find bedrock? what is bedrock?

A

c= parent material

-solid rock underlies soil and other unconsolidated material

27
Q

what is the easiest way to characterize soil?

A

-physical characteristics : colour and texture

28
Q

what are 3 categories of colour in soil

A

dark, mod dark and light

29
Q

how is soil texture characterized?

A

-expressed in terms of % sand, silt and clay

30
Q

how many textural classes are there?

A

12

31
Q

describe texture characteristics of sand

A
  • 3D, round, gritty
  • large particles= more drainage
  • dif to retain water
32
Q

describe texture characteristics of silt

A
  • 3d, round floury texture
  • smaller particle
  • increased retention, less drainage
33
Q

describe texture characteristics of clay

A
  • small flat particle form impenetrable plates

- min drainage, dif aeration

34
Q

what does texture of soil refer to

A
  • size distribution of mineral particles found in sample
35
Q

what is the most important mineral particle found in soil? and why?

A

clay ; highly reactive, ability to attract and hold positively charged nutrient ions

36
Q

what are aggregates

A

grouping of soil particles into porous compounds

37
Q

t ir f; soil structure is stable

A

false; aggregates can be destroyed by tiliage, compaction and depletion

38
Q

how can aggregates be destroyed

A

tillage, compaction, depletion of sol organic matter

39
Q

t or f, poor soil structure in creases total porosity

A

false; good structure increase porosity because large pours b/ween aggregates= better root penetration and air and water movement

40
Q

what pH is considered acidic? alkaline ?

A

6-1; 8-12

41
Q

t or f; soil pH can influence plant growth, quantity activity and types of microorganisms

A

true

42
Q

t or f soil ph does not impact nutrient transformations and solubility of essential nutrients available to plants

A

false

43
Q

what essential micronutrient is available in slightly acidic- slightly alkaline soil?

A

phosphorus

44
Q

essential micronutrients become more available with ___ ph

A

decreasing ( more acidic)

45
Q

at what pH level can essential micronutrient become available to a point of toxicity in plants? what essential micronutrients do these include?

A

<5.5; Al, Mn, Fe

46
Q

what are important mediators on nutrient exchange systems? where are they most active?

A

bacteria, slightly acidic- slightly alkaline

47
Q

what are On soils mostly containing?

A
  • calcareous; limestone parents rock material

- higher Ca= higher pH

48
Q

what is the main problem with ‘designer soils’

A
  • contain too much organic matter

- can’t be sustained naturally over time decomposes an d settles

49
Q

what are mycorrhiza?

A

symbiotic relationship b/ween fungus and root

50
Q

t or f; soil fumigants, excess fertilizer, excessive irrigation, poorly drained soil inhibit mycorrhizae activity

A

true

51
Q

name 7 things that encourage mycorrhizal activity

A
  1. coarse woody mulch
  2. consv. additions of N fertilizer
  3. warm temp
  4. mild drought/ nutrient deficiency
  5. reduced pesticide
  6. reduced aoil disruption
    - increase plant diversity
52
Q

what are the top 3 ways to improve soil conditions

A
  1. cover cropping
  2. muching
  3. composting
53
Q

__% of landfill waste is food waste

A

20

54
Q

what happens when food decomposes? why is this an issue?

A

-release of methane gas, heat up earth 20 times faster than CO2

55
Q

what is vermicomposting?

A
  • ’ cold composting’
  • lower carbon to nitrogen ratio
  • uses worms to compost

ECOL 1001 (8 decks)

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