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GEOG 305 Final > Lecture 13-15 > Flashcards

Lecture 13-15 Flashcards

1
Q

What are the 4 phases of soil formation?

A

Bedrock begins to disintegrate

Organic materials faciliate disintegration
- appearance of OM

Horizons form
- appearance of A horizon
- Parent material and C horizon

Developed soils support thick vegetation
- A, B, and C horizon

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2
Q

What is the O horizon?

A

OM layer on the top

Also known as LFH horizon
- L = litter
- F = fiber material
- H = humus (relates to the decomposition state of the litter)

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3
Q

What is the Ah horizon?

A

Enrichment of humus

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4
Q

What is the Ae horizon?

A

Depletion of humus and particular soil minerals (clay minerals)

The e represents eluviation (washing away)

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5
Q

What is the B horizon?

A

There is a huge variety
However, mainly minerals

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6
Q

What is the C horizon?

A

Soil particles and bedrock material

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7
Q

What horizons is the topsoil made up of?

A

LFH and Ah horizon

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8
Q

What horizons is the transition layer made up of?

A

Ah

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9
Q

What horizon is the subsoil made up of?

A

Horizon B

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10
Q

What horizon is the weathered/solid bedrock made up of?

A

Horizon c

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11
Q

What are the 4 soil forming processes?

A

Additions: precipitation (with included ions and solid particles), OM, human processes (fertilizer, grazing,), feces, etc.

Transformations:
- OM –> humus
- Primary minerals –> secondary minerals, hydrous oxides, clays, ions, H4SiO4

Transfers downward: humus compounds, clays, ions, H4SiO4

Transfers upward: Ions, H4SiO4
- upward direction of ions is from capillary action from water table (groundwater rises and carries dissolved ions, some of these ions may be left behind within the soil profile)

Removals: ions, H4SiO4
- due to human activity (harvesting, etc.)
- leaching to groundwater
- erosion

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12
Q

What are the 5 soil forming factors?

A

Parent material
Climate
Organisms (including humans)
Topography
Time

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13
Q

Parent material

A

Substrate from which the soil starts to develop
There is residual parent material (such as rocks) but also transported parent material

Chemical and mineralogical composition of the parent material influences degree of weathering and soil chemistry

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14
Q

What is residual parent material?

A

Bedrock
- can be igneous or sedimentary

Igneous
- Canadian shield mostly formed of igneous rock types

Sedimentary
- more prone to weathering
- Saint-Lawrence lowland is mostly sedimentary rock

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15
Q

What is transported parent material?

A

Parent material that was transported by water, gravity (landslides), ice (glaciers), and wind

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16
Q

What parent material do water transported rocks and minerals form into?

A

Can be deposited in:
- Lakes = lacustrine
- Streams = alluvial (fluvial)
- Oceans = marine

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17
Q

What parent material does gravity transported rocks and minerals form into?

A

Colluvial

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18
Q

What parent material does ice transported rocks and minerals form into?

A

Can be deposited By
- Ice = till, moraine
- water = outwash lacustrine, alluvial, marine
- wind transpored = eolian

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19
Q

What parent material does wind transported rocks and minerals form into?

A

Deposited by wind = eolian

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20
Q

How are floodplains created?

A

Floodplains are created when the high flow recedes (high flows have a lot of sediment and OM transport)

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21
Q

What happens to soil growth when there are a lot of flooding events?

A

Soils grows upwards rather than downwards
- layers refer to flooding events

Example deltas

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22
Q

What are moraines?

A

Transported by ice (glaciers)

Glaciers flow down from mountains into valleys

Mixture of fragmented rock that is transported down

Frontal moraines –> glaciers are pushing earth forward

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23
Q

What is a glacial till?

A

What has been lying below a glacier

Glacier eroded the rock below it

Important in regions that were covered by ice sheet during last glaciation (example Saint-Lawrence lowlands)

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24
Q

Dust as parent material (eolian)

A

Dust plumes can be transported across the Atlantic ocean and deposited on the Amazon rainforest

Dust becomes parent material

Important role as fresh parent material and nutrients in old and higher weathered soils such as Hawaii

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25
Q

What is a loess?

A

Transport of dust that is so intense that it creates a parent material similar to alluvial plain

Created during the last Ice Age

Very fertile soil since it has good soil hydrological properties (good at providing water for plants)

Provides habitats for birds

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26
Q

What are the factors that make climate an important soil forming factor?

A

Precipitation and temp.

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27
Q

How does temperature and moisture impact clay content?

A

The higher the soil moisture, the higher the temp. –> the more clay content you can find since weathering processes of primary minerals into secondary minerals are accelerated

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28
Q

Explain the transition of soil properties/type according to climate

A

Polar desert –> little chem. alteration
Tundra: Appearance of illite-montmorillonite
- cold and dry = no soil dev. and very little chemical interactions

Taiga: formation of 1:1 clay minerals
- precipitation and temp. increases slightly –> smectite and kaolinte formation

Tropics
- higher precipitation and temp. –> development of deep tropical soils
- top layer called oxisols because dominated by iron and aluminum oxides
- formation of sesquioxides

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29
Q

How do organisms influence soil-forming factors?

A

Vegetation
Soil organisms
Human activities

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30
Q

How does vegetation impact grasslands?

A

Thick Ah horizon since grass vegetation has a very dense and thick rooting system. When they die they add a lot fo OM to the soil and into deeper soil layers

Absence of Ae horizon

CaCO3 closer to surface

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31
Q

How does vegetation impact forests?

A

Rarely water limited, therefore thin Ah horizon and leached Ae horizon (more prec.)

Thick B horizon

Higher output pathways –> higher rates of decomposition (because higher moisture/higher erosion and leaching)
- erosion, leaching, and decomp. of SOM is higher in forests than in prairies since it has more precip.

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32
Q

How does vegetation impact deciduous ecosystems?

A

Higher CEC

Higher pH (less acidic)
- Because litter decomposes much quicker in deciduous forests (thereby reusing the cations that are stored within the litter)
- Coniferous trees shed waxy needles that decompose much more slowly

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33
Q

How did earthworm invasion impact soil profile in New Brunswick?

A

Disappearance of F and H layer

Mineral and humus layer became well mixed (Ah horizon)

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34
Q

How do humans impact soil-forming factors?

A

Changes vegetation cover (grasslands and forests are converted to agricultural land)

Drainage of wetland and peat soils

Addition of fertilizers to soil

Atmospheric deposition of pollutants (acid rain, N deposition)

Transport of soil for agricultural purposes

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35
Q

How does topography impact soil-forming factors?

A

Determines drainage class and accumulation and removal of material

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36
Q

Explain the erosion, accumulation, and soil moisture on a hill

A

On a slope: A and B horizon much more shallow since it is eroded away
- restricted drainage
- luvisols

On the top of the hill:
- water table is deep (does not influence as much soil formation)
- free drainage
- gleysols

At the bottom of a hill
- water table is much higher, therefore has an influence on drainage
- more diverse and complex soil horizons
- poor drainage
- organic soils

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37
Q

How does time impact soil-forming factors?

A

Slow impact of processes on parent material leading to steady state

Where soil-forming factors have changed through time, age of soil may be important explanatory factor, rather than present-day conditions

That is why it is important to have geological knowledge of the area you are working in

Examples: Montreal
- soil developed when the glaciers receded 10 000 years ago and left behind glacier till which become the substrate of soil development

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38
Q

Explain soil development over time on Loess

A

Fresh loess deposited:
- relatively unweather loess

As time goes on
- beginning of accumulation of CaCO3 + CaSO4 at the surface
- that layer begins to deepen
- formation of A horizon that progressively deepens as well
- LFH horizons (more vegetation)

10, 000 years
- A horizon
- Bt: accumulation of clays
- Bc
- Ck

Soil grows in both direction (addition on the top and transformation downwards)

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39
Q

What are the benefits of factorial approach to soil formation?

A

Reduces complex, spatially-variable soils to simple environmental relationships

Allows predictions of soil types in the field and properties, base don easily measured factors

Allows easy mapping of soils, from easily determined factors

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40
Q

What are the limitations of factorial approach to soil formation?

A

Often assumes factors are independent when they are frequently inter-dependent

Over simplification: tends to ignore processes which are the real explanation

Soils are often polygenetic (have formed under differing soil forming factors)

Factorial appraoch is a concept most applicable in temperate regions
(since non-glaciated areas differ)

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41
Q

Why do we classify soils? What is the problem with soil classification?

A

To help communicate information
To make predictions
To establish inter-relationships among soils and their envr.

However, soils are a multi-property body, with great spatial and temporal variability, particularly with respect to soil moisture but also in other properties
- Horizon borders are often blurred

42
Q

What are the categorical levels of soil classification?

A

Order: properties that reflect envr and soil forming processes

Great Group: subdivision of order reflecting difference in dominant processes

Subgroup: differentiated by content and arrangement of horizons

Family: differences in texture, minerology, climate and chemistry

Series: detailed features of the pedon differentiate subdivisions of the family

43
Q

What are the three mineral horizons in the Canadian System of Soil Classification?

A

A, B, and C followed by lowercase suffixes

Connects parent material with soil

44
Q

What are the four organic horizons in the Canadian System of Soil Classification?

A

O, L, F, H

O horizon is further defined by suffixes

45
Q

A horizon suffixes and description

A

Ah: accumulation of SOM (h stands for humus)
Ae: removal of clay, SOM, iron, or aluminum (e stands for eluviation)

46
Q

B horizon suffixes and description

A

Bh: accumulation of SOM

Bf: accumulation of iron and or aluminum

Bss: presence of slickensides (smooth clay coating caused by stress in clay soils)

Bv: vertic horizon caused by turbation (mixing) of material in high clay soils

Bt: accumulation of clay

Bn: strong soil structure and sodium accumulation

Bg: mottling and gleying due to water saturation

Bm: slight colour or strucural changes from the parent material

47
Q

C horizon suffixes and description

A

Cca: accumulation of Ca and Mg carbonates

Cs: accumulation of soluable salts

Ck: presence of orginial Ca and Mg carbonates

Css: presence of slickensides

Cg: mottling and gleying due to water saturation

48
Q

R horizon description

A

Consolidated bedrock

49
Q

W horizon description

A

Water layer

50
Q

O horizon suffixes and description

A

Of: composed of fibrous materials of readily recognizable origin (f stands for fibrous material)

Om: organic materials in an intermediate (or mesic) stage of decomposition

Oh: organic material which is highly decomposed (in a humic state) (h stands for humus)

51
Q

L horizon description

A

Leaf litter, ready recognizable

52
Q

F horizon description

A

Partially decomposed leaf and twig material (folic material)

53
Q

H horizon description

A

Humic material
Decomposed OM with no original structures

54
Q

What are the 10 soil orders of the CSSC

A

Brunisols
Cryosolic
Chernozemic
Gleysolic
Luvisolic
Organic
Podzolic
Regosolic
Solonetzic
Vertisol

55
Q

Regosolic soils description

A

Occus in every ecozone but are rarely dominant in the landscape
- 2% of the surface in Canada

B horizon is absent (or only has limited dev.)
- only consists of A horizon

Form on young materials, fresh alluvial deposits, post volcanic eruptions, sand dunes, mass wasted slopes, dry and cold conditions

56
Q

Brunisolic soils

A

Forms under mixed forests
- widely distributed in Canada (14%)
- Saint-Lawrnece lowlands, Northern qbc, regions of central provinces, as well as BC and Yukon

Brownish Bm horizons
- slight colour or structural changes from the parent material
- not yet chemically altered a lot (slight changes in colour and chem. composition)
- clearly distinguished from B horizon

A stage of an evolutionary sequences that begins with parent material and ends with Podzols or Luvisols

Medium fertility

In ecozones where mean annual precip. <700 mm

The parent materials are derived from igneous rocks and typically have moderately or highly acidic pH values

57
Q

Luvisolic soils

A

Develop beneath mixed deciduous and coniferous forests (one of the three orders for forested soils)
- Usually in the south

Parent materials are rich in base cations such as calcium and magnesium –> high fertility
- used for farming purposes (good for crops)
- Ap (Ah horizon) –> p stands for plow
- agricultural soils: A horizon straight line because it is promoted by farming practices

Neutral or alkaline pH values although some acidic luvisols are found in eastern Canada

Eluviation and illuviation produce Ae and Bt horizons
- seen by presence of Ae and Bt horizons
- Ae = strong eluvation, washing out of humus and clay minerals into deeper layers
- These materials accumulate into deeper layers which creates Bt horizon and sometimes Bh horizon

58
Q

Podzolic soils

A

Develop beneath coniferous forests (acidic needles) and on sandy parent materials
- Norther qbc, BC
- 14% of Canada

Means annual prec. >700 mm

Low to medium fertility depending on acidity
- the more acid, the less fertile

Intense chem. weathering in the upper part of soil
- Al, Fe, and other ions are weather away from topsoil into deeper layer

Metals ions form complexes with the org. decomp. products (called chelates)

Develop in cool and wet climate –> have rich LFH horizon

LFH horizon
A horizon (light pale layer): eluvation of bases, oxides, clays
B horizon: illuvation of oxides and clays
C horizon: loss of base to water table, acc. of oxides and clays

59
Q

Horizons in podzolic soils

A

Ae: a lot fo elivation and washing out of materials (pale colour)

Darker colour: a lot of OM eluviated into this horizon from the trop

Reddish colour: eluvation of iron and Al oxides that accumulate and create the colour

Bfh: mineral horizon, very enriched in humus, OM material
- Bf is a lyer with strong acc. of iron and Al oxides

60
Q

Vertisolic soils

A

Very high clay content (>60%)

Little dev. of horizons (large amounts of smectice)

Shrinking and welling upon drying and wetting
- diagnostic feature are cracks

Occuring primarily in cool subarid grasslands throughout the Prairie ecozone
0 0.3% of surface area in Canada

Parent materials were deposited in lakes that existed during the retreat of the last (Wisconsian) glaciers between approx. 17000 to 9000 years ago

Has Ah horizon with OM
Bv: v stands for vertic (means that it is very high in clay and quite fertile)

61
Q

Gleysolic soils

A

Influence by the presence of water
- When O is preset, Fe is oxidized and has reddish colour
- Water saturation leads to depletion of O -> iron is reduced into Fe2 and takes on a blue-grey hue

High water table and develop in the vicinity to rivers and lakes
- water table can rise up and create situations where there are anoxic pockets

Diagnostic Bg (g for gley) horizon develops

Medium to high fertility
- depends on the soil in the vicinity to the body of water

62
Q

How do gleysoils influence N and P pathways?

A

P is often found to rion oxides. When iron is reduced, P becomes mobilized and can be transported away from the soil into the body of water

Nitrates in anoix conditions become reduced and lost into the atmosphere

Therefore, gleysols can reduce the input of nitrates in freshwater bodies but can promote P in waterways

63
Q

Organic soils

A

Prominently found in Hudson bay lowlands
- 9% of Canada

Composed largely of OM including peat, bog, and muck soils

Commonly saturated with water for prolonged periods

Low to medium fertility depending on drainage and nutrient availability

Associated with landscape positions where water accumulates and saturates the soil
- ex. acc. of water in topographic low points

Cooler climates slow decomp. of OM therefore OM can accumulate more

Develop because input of OM is higher than output through decomp.

64
Q

How is peat soil formed?

A

waterlogged, anaerobic, cold conditions leading to slow rates of OM decomp.

65
Q

Why are peatlands important in terms of carbon?

A

Important since huge carbon sinks

However, because they are good for vegetable production, they are drained.
- OM begins to decompose (since exposed to O)

66
Q

Cryosolic soils

A

Usually found north of the treeline
- 28% of Canada
- North

Ah horizon is lacking or very thin (a lot of enrichment of humus)

Cryturbation is common –> ground circles, polygons, stripes
- Diagnsitc feature: strange features forming. Organic horizons translocated in deeper layers since melting and freezing of ice moves soil layers around and disturbs layers

Mean annual temp <0 (cold conditions, often develop in permafrost landscapes)

Fertility ratings are not applicable because they are dominated by ice or permafrost

Cryosols may be found in association with other soil orders (eg. organic soils of gleysoils)

Weak chem. dev.

LFH and Ah horizons are underlined by thick ice layer

These soils are strongly disturbed by climate change when ice melts

67
Q

Chernozemic soils

A

4% of Canada
- Prairie

Black earth

Well to imperfectly drained soils

OM accumulation
- thick surface layer

Majority of carbon input occurs below ground through the dev. of extensive root networks of grasses

High fertility mostly because they have relatively high pH??? (rich in base cations,P, and large amount of SOM)
- very limited leaching of bases
- neutral pH???

Dissolved salts from topsoil often precipitate in the upper C horizon (Cca)

15-30% of the original soil carbon was lost after converstion of the nature Prairie to agriculture

68
Q

Solonetzic soils

A

Found in the Prairies where it is dry (high evaporation leads to acc. of salts)
- 1 % of Canada

Associated with salinity and alkalinity

Very hard B horizon when dry and sticky mass with low permeability when moist

Variable fertility

Distribution of salts throughout soil profile
- usually not useful for crop prod. because pH is high due to acc. of salt minerals
- Salinization promoted by irrigation with groundwater (groundwater is rich in irons since in contact with parent material).
- The combination of groundwater irrigation and high evaporation leads to acc. of salts in the soils

Salinization when dissolved salts migrate to surface in areas with high evapotranspiration

69
Q

What is soil erosion?

A

Naturally occuring process that affects all landforms

Refers to the wearing away of the topsoil by physical forces of water and wind or through forces associated with human activities (tillage, cattle grazing, tree harvest)

Topsoil which is high in OM, fertility, and soil life is detached, moved, and deposited elsewhere

Reduces the productivity of corlands and natural ecosystems and contributes to the pollution of adjacent watercourses, wetlands and lakes

70
Q

What is soil creep?

A

Slow downslope movement of soil particles in response to disturbances
- Movement of topsoil and subsoil

Slow process

Expansion/contraction with wetting/drying

71
Q

What are landslides and earthflows?

A

Rapid mass movements when soil strength is exceeded by gravity, usually heavy rainfall

All of a sudden, a large mass of soil moves

Often in the tropics due to heavy rainfall

72
Q

What is fluvial erosion?

A

Erosion by running water
- Caused by overland flow of water that moves on top of the soil (does not relate to subsoil)

By far the most important form of erosion

73
Q

What is aeolian erosion?

A

Wind removel of surface layer

Requires the absence of protective vegetation cover, dry soils and strong winds

Occurs usually in dry soils

74
Q

What are the 3 processes of fluvial erosion of soil?

A

Raindrop impact and splash

Creation of overland flow

Deposition

75
Q

Explain the draindrop impact and splash

A

Raindrop hits bare soil unprotected from vegetation

Impact and subsequent splash leads to the destruction of the soil aggregates and topsoil structure (detachment)

Soil aggregate is destroyed and smaller particles can be moved away by flowing water (transport)

Particles can be deposited elswhere (deposition)

76
Q

What are the 3 types of overland flow erosion?

A

Sheet erosion:
- A whole area is eroded simultaneously
- Can be observed in the environment
- Caused biggest damage to agricultural systems (since it multiplies over the years and affects large area)
- Can lead to burial and suffocation of crops

Rill erosion
- Certain locations (rills) experience more erosion
- Creation of channel -> surrounding water will flow and accelerate erosion
- Areas around are spared from erosion

Gully erosion
- Creates deep channels called gullies
- From strong precipitation
- Excessive rill erosions

77
Q

What is Horton overland flow (HOF)?

A

the tendency of water to flow horizontally across land surfaces when rainfall has exceeded infiltration

78
Q

What are the two factors that overland flow is affected by?

A

Vegetation cover (prevents splash impact)
Soil infiltration (determined by soil structure –> presence of SOM)

79
Q

Compare the interception, overland flow, and infiltration in a vegetated forest, a forest without litter or humus, and unimproved pasture

A

Oak hickory: same interception, low overland flow, high infiltration rate

Forest w/out litter/humus: same interception, higher overland flow, lower infiltration

pasture: no interception, high overland flow, lowest infiltration

80
Q

How is soil erosion measured?

A

Collect soil downslope in troughs: measures weight of particles deposited in it

Measure loss of soil against stable surface (tree root)

Radionucleotides: using radionuclotides from old nuclear explosion to estimate soil erosion

81
Q

What are some problems with measuring soil erosion rates?

A

Large temporal and spatial variability

Labour-intensive and expansive

Difficult to scale-up from small plots to drainage basins and landscapes

Of little predictive value (only gives measurement from one pt in time)

82
Q

What is the Universal Soil Loss Equation?

A

A = R x K x LS x C x P

where,
A=erosion rate (tons ha^-1yr^-1)
R=rainfall erosivity
K=soil erodibility
LS=combination of length and slope of field
C=crop type
P=conservation measures applied

83
Q

What are the two factors of rainfall erosivity (R)?

A

Rainfall intensity: affects creation of overland flow by exceeding soil infiltration rate

Rainfall energy: ability to splash soil particles downslope and destroy soil aggregates
- gravitation energy: height from which the raindrop is coming from and size of the raindrop

84
Q

Explain the distribution of rainfall erosivity in the world

A

Lowest in desert and arid regions

Highest in humid regions and North East since has more rainfall intensity occuring (exceeding infiltration)

Monsoon in Asia also causes high rainfall erosivity

85
Q

What is soil erodibility (K)?

A

Potential of soil to become eroded
Depends on soil textures since it determines the water infiltration rate

Combination of:
- Soil infiltration rate
- Ease of detachment of soil particles
- Ease of transport of soil particles

86
Q

What is the order of soil infiltration rate of sand loam and clay?

A

sand>loam>clay

87
Q

What is the order of ease of detachment of soil particles of sand silt and clay?

A

silt>clay>sand

Silt is detached the easiest due to bonding strength

Clay size fraction is dominated by clay minerals which have highly charged surfaces that bind to SOM that form aggregation which prevents the small particles from detaching

Sand particles are big and not as easily transported away

88
Q

What is the order of ease of transport of soil particles of sand silt, gravel and clay?

A

clay>silt>sand>gravel

89
Q

What soil texture has the highest soil erodibility values (K)?

A

Silt loam

90
Q

What are the factors that affect the slope-length factor (LS)?

A

Longer slopes mean greater cumulative overland flow from upslope, leading to faster movement and greater capacity to erode and carry soil

Steeper slopes mean faster overland flow and greater capacity to erode and carry soil
- the steeper the slope, the higher the LS factor

91
Q

What is the soil erosion equation used for?

A

Predict erosion raets for individual fields

Devise conservation measures to ensure that erosion rates are less than that regarded as intolerable

A, R, and K defined, farmer can change slope angle, field lengt , crop type or conservation practice

92
Q

What does a crop (C) value and conservation (P) value of 1.0 represent?

A

Bare soil, no conservation

93
Q

What are the envr effects of accelerated rates of soil erosion on site?

A

Reduced water availability
- increases surface runoff (reduces water for plant growth)
- removes finer particles (clay, OM) leaving sand and gravel particles which have lower available water capacity

Reduced soil fertility
- leads to loss of fertilizers, especially N and P, by overland flow
- removes smallest particles (clay, OM) which have highest available nutrient content and CEC

Reduces rooting depth for plants (shallower soils)

Gully creation
- loses agri. land
- increases accessibility costs of farming

Greater energy costs
- for ploughing and tillage
- for seeding and fertilizer needs

94
Q

How does soil erosion promote a positive feedback loop?

A

Exposure of lower soil horizons by erosion –> decreased infiltration rates –> increasing overland flow –> less vegetation –> more surface layer removal –> more erosion –> exposure of lower soil horizons –>

95
Q

What are the envr effects of accelerated rates of soil erosion off site?

A

Sedimentation of eroded soil in river channels, dams, reservoirs

Leads to eutrophication of water bodies (rivers, lakes)
- N and P transported and adsorbed to eroded soils
- pesticides transfer from land surface to aquative system through erosion

Deteriotation of water quality and higher water treatment costs

Increased frequency of flooding
- greater surface runoff and channel volume may be reduced by deposited soil
- larger amount of HOF –> accumulates downstream in smaller channels –> increases frequency of flooding

96
Q

What is a conservation method developed for agriculture in loess plateau regions?

A

Terraces because they limit soil erosion, retain water during dry season

97
Q

What are some strategies to reduce fluvial erosion rates in agricultural systems?

A

Change crop type or planting/harvesting schedules (C)

Protect soil surface and increase infiltration rate
- add OM (K)
- change tillage practices (no till or less intense ploughing) (K)

Change length and angle of field by creating terraces or ploughing parallel to slope (LS)

Reduce grazing densities to allow grass cover: 25% grass cover is critical in reducing erosion rates (C)

98
Q

How is contour ploughing beneficial?

A

Crops parralel to slope will slow down water movement downhill

Plant and remove crops layers at different times decreases erosion rates

99
Q

What can wind erosion be caused by?

A

Creeping of larger particles

saltation of medium sized particles (airborne for short amount of time)

suspension of smaller particles of clay and silt size fraction

100
Q

What are ways in which wind erosion can be controlled?

A

Maintain soil moisture

Cover soil

Reduce tillage and timing of tillage

Create barriers

101
Q

What are shelterbelts?

A

Rows of trees planted in between agricultural crops to break up wind and prevent wind erosion

They are barriers that can prevent soil erosion from wind

102
Q

How does erosion impact food security?

A

Soil erosion cuases SOM to deplete (lowers fertility of crops)

There is a decline in agricultural production which leads to food insecurity

Food insecurity leads to more intensive agricultural practices which leads to more erosion

GEOG 305 Final (3 decks)

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