Soils Exam 1

Question 1

Pedon

Answer 1

A 1X1X1.5 M DEEP UNIT OF SOILIS REFFERED AS A PEDON.

Question 2

Regolith

Answer 2

Volume of soil between surface and bedrock

Question 3

Soil functions

Answer 3

• Supports plant life in our biosphere
• Harbors thousands of types of saprophytes (organisms that eat or decompose dead organisms)
• Serves as foundations for homes, industries and highways
• Absorbs harmful contaminants from surface h20
• Filters pathogens/parasites from waste water

Question 4

Four ways soils support plant life

Answer 4

• Anchor plant roots
• Supply water for plan roots
• Supply air for plant roots
• Furnish roots for plant growth
• Release water with low levels of nutrients

Question 5

Types of rocks

Answer 5

• Igneous Rocks
• metamorphic rocks
• Sedimentary rocks

Question 6

Rocks

Answer 6

Collection of minerals

Question 7

Hydrologic Cycle

Answer 7

Breaks rocks to form soils

Question 8

Rock + Rain=

Answer 8

The current landscape+soil

Question 9

Five hills lope position

Answer 9

Summit
Shoulder
Back slope
Foot slope
Toe slope

Question 10

Soil forming processes

Answer 10

• Losses(erosion)
• Additions(deposition)
• Translocation
• Transformation

Question 11

Soil forming factors

Answer 11

• Parent material
• Topography
• Climate
• Time
• Organisms

Question 12

Different types of parent materials

Answer 12

• Alluvium-water-river-flood plains
• Colluvium-gravity-foot slope
• Lacustrine-water-lakes-dried up lake beds
• Aeolian-wind-wind blown deposits
• Marine-ocean-exposed ocean deposits
• Glacial till-retreating glaciers-broad glacial plains
• Glacial outwash-melt water from glaciers-areas with in glacial areas

Question 13

Soil Horizons

Answer 13

• surface
• topsoil
• subsoil
• substratum
• bed rock

Question 14

Texture

Answer 14

Soils containing large
amounts of sand exhibit
little plasticity and cannot
retain large amounts of
water or nutrients. They
have large voids
(macropores) that readily
transport water and air.

Question 15

Mineral fraction of soils

Answer 15

Sand Silt Clay
Diameter of particles
0.05-2 mm 0.002-0.05 mm <0.002 mm

Question 16

Soil Color

Answer 16

 Useful tool for providing
information about other
soil properties
 Organic matter content
 Soil minerals
 Seasonal high water tables

Question 17

Structure

Answer 17

The arrangement of
primary soil particles into
compound particles or
aggregates.
 The type and grade of
structure plays an
important role in the
movement of water within
soils.

Question 18

Minerals particles having an average diameter>2mmare termed gravel..

Answer 18

and are not used to calculate soil texture

Question 19

NOT TRUE ABOUT TEXTURAL CLASSES

Answer 19

They are closely related to its color
There are 11
They are related to structure

Question 20

Dull-gray coloration of an iron-rich mineral soil profile, particularly with increasing depth, indicates

Answer 20

saturation or seasonal water table

Question 21

The hue of a soil is considered non-existent, and denoted as N, when the:

Answer 21

Chroma is 0

Question 22

Soil color can be highly indicative of:

Answer 22

• OM content, parent material, and/or degree of seasonal saturation (drainage)
  B) Sand content, parent material, and/or calcium content
  C) Soil fertility (namely base saturation)
  D) OM content and nematode infestation
  E) Horizon depth and load-bearing capacity
  F) Sand content and shrink-swell characteristics

Question 23

Redox depletions, localized pockets of soil where anaerobic conditions persist, take on a ‘gley’ color in which chroma is low (less than or equal to 2) and value is typically:

Answer 23

greater than or equal to 4

Question 24

Which type of soil structure is common in soil horizons dominated by shrinking-swelling clays?

Answer 24

Wedge

Question 25

Which soil structure most impedes movement of water through the soil?

Answer 25

Massive | Platy

Question 26

In the majority of upland soil profiles, this component of soil color increases with depth:

Answer 26

Value

Question 27

The hue of a soil is considered non-existent, and denoted as N, when the:

Answer 27

Chroma is 0

Question 28

Which type of soil structure is common in soil horizons dominated by shrinking-swelling clays?

Answer 28

Wedge

Question 29

Soils residing in the 'sand' textural class are often specified in construction of important, highly-trafficked turfgrass systems to enhance long-term:

Answer 29

``` - Infiltration and permeability B) Cation exchange capacity (CEC) C) Erodibility D) Available water holding content E) Shrinking and swelling characteristics ```

Question 30

Of the following soil properties, which is least-related to soil texture?

Answer 30

``` -Soil color B) Permeability C) Soil textural class D) Available water holding content E) Erodibility F) Infiltration G) Shrink-swell characteristic H) Porosity ```

Question 31

If you excavated a perfect 3x3x3-cm cube of dry soil and determined it's mass to be 40 grams, the bulk density of that soil is:

Answer 31

1.48 g/cm3

Question 32

Imagine you have a pure quartz sand. Furthermore the sand is exactly 50% pore space by volume. Knowing the particle density of quartz to be 2.65 g/cm3, what's the bulk density of this pure quartz sand?

Answer 32

1.325 g/cm3

Question 33

You find a steel ring having a 4 cm inner diameter, a height of 1.5 cm, and a mass of 7 grams. Nice find! Imagine you took that ring to the field, packed it with soil, dried it in an oven, and let it cool. Later, you determine the oven-dry soil and ring (together) weigh 30.6 grams. What is the bulk density of the soil you collected?

Answer 33

1.4 g/cm3

Question 34

A dry soil clod weighs 48 g. When you then tie a string around it, dip it in hot wax, and determine the volume of water it displaces, you realize this dry, water-tight, SOIL CLOD has a volume of 27.5 cm3! Using 2.65 g/cm3 for particle density, what do you estimate the porosity within the soil clod to be?

Answer 34

less than 35%

Question 35

You find a steel ring having a 8 cm inner diameter, a height of 1.5 cm, and a mass of 32 grams. You feel lucky and want to do the right thing, so you take it to a field, pack it with soil, dry it in an oven, and let it cool. Later, you determine the oven-dry soil and ring (together) weigh 148.9 grams. Using a particle density of 2.65 g/cm3, what do you estimate the porosity of the soil you collected to be?

Answer 35

41.5 %

Question 36

simplistic

Answer 36

a surface blend of ssc and or organic matter material in witch plans grow

Question 37

Weathering: Physical Breakdown

Answer 37

expansion/contraction | abrasion

Question 38

Weathering: Chemical Alteration

Answer 38

decomposition of minerals | hydrolysis

Question 39

Primary minerals

Answer 39

created with magma deep with in the earth

Question 40

Secondary minerals

Answer 40

formed at earth surface from chemical(weathering) of primarily minerals