soils exam 3 LO:26-35

what horizon is mollic

A

what horizon is umbic

A

what horizon is ochric

A

what horizon is melanic

A

what horizon is histic

O

another name for clay skins

argillans

what are the 5 subsurface horizons found in SC

albic

argillic

kandic

spodic

cambic

what does the subscript b mean

buried horizon

what does the subscript g mean

gleying

what does the subscript h mean

illuvial of organic matter

what does the subscript p mean

plowing/disturbance

what does the subscript r mean

soft bedrock

what does the subscript s mean

illuvial sesquioxides and O.M.

what does the subscript t mean

clay accumulation

what does the subscript w mean

development of color/stucture

what horizon is albic found in

E

what is the Value and color of an albic horizon

white

V: greater than/ equal to 5

C: greater than/ equal to 2

what horizon are albic horizon found over

Bh or Bt

what grain texture is albic

sandy

does albic have high or low CEC

low

is albic high or low in clay

low but fe and al oxides

what percent of increase of clay must there be to be considered argillic or kandic

20% (x1.2)

CEC for argillic

greater than/ equal to 16

CEC for kandic

less than 16

between argillic and kandic which has high clay activity

argillic 2:1, kandic only 1:1

between argillic and kandic which is illuviation necessary

kandic

between argillic and kandic which has clay skins

argillic

why does clay skins occur

clay particles are transported with percolating water and dry between peds leaving a coating of clay

what do clay skin look like

shiny glossy film

above a B horizon is an A and E horizon, which one should you look at to tell if the B horizon is a Bt

A

spodic color and value

less than 3

does spodic have high or low base saturation

low, acidic

what conditions does spodic form under

acidic and humid

what sesquioxides are in a spodic horizon

Al AND Fe

what common subscripts are seen with spodic horizons

h and s

name this subsurface horizon

spodic

what habitats does spodic horizons appear in

pine forrest, conifer forrest, acidic places

what subscrips are seen with cambic horizon

w and g

what subsurface is known as “young soils“

cambic

Bw

weak structure

minimal clay accumulation

weak color altercation

Bg

GLEYING

reduced Fe and Mn fron saturation

C: ≤2

V: ≥4

where are Bg horizons found

floodplains

what PM is found with Bg and Bw horizons

alluvium

what epipedon is paired with Bw and Bg subsurface horizons

ochric

what horizons are cambic subsurface horizons found in

B and some C

summarize albic horizon

elluvial, low reactivity, V ≥5, C ≤2

summarize argillic horizon: Bt

illuvial accumulation of clay

CEC ≥ 16

clay skins

summarize kandic: Bt

illuvial accumulation of clay

CEC <16

summarize spodic horizon (Bs)

illuvial accumulation of OM

Al sesquioxides

V < 3

C < 3

summarize spodic horizon (Bw)

illuvial accumulation of OM

Al and Fe sesquioxides

V and C: <3

summarize cambic Bw

minimal change from PM

minimal clay accumulation

summerize cambic (Bg)

saturated

gley matrix

V ≥ 4

C ≤ 2

taxonomy hierarchy from most broad to lease

order

suborder

great group

sub group

family

series

what is the sub-group name in this example

Lynchburg soil series:

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

what is the family name in this example

Lynchburg soil series:

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

what is the great-group name in this example

Lynchburg soil series:

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

what is the sub-order name in this example

Lynchburg soil series:

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

what is the order name in this example

Lynchburg soil series:

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

Fine-loamy, silaceous, semiactive, thermic Aeric Paleaquult

what are the 5 moisture regimes from wet to dry

1. aquic

2. udic

3. ustic

4. aridic

5. xeric

aquic freatures

saturated soils

reduced Fe

gleying

poor aeration

what fraction does udic make up of all soils

1/3

how often is udic soil dry

less than 90 days out of the year

ustic features

PAW during growing seasons

periods of drought

how often is aridic soil wet

less than 90 days out of the year

ardic features

wet less than half the growing season

droughts

what kind of climates is Xeric found in

cool, moist winters

and warm, dry summers

xeric features

long periods of droughts

what are the 5 temp regimes from coldest to hottest

1. cryic

2. frigid

3. mesic

4. thermic

5. hyperthermic

how far down is temperature regimes measured

50 cm

how are temperature regimes calculated

mean annual soil temp

what temp is cryic soil

less then 8 degrees C

what temp is frigid soil

less then 8 degrees C

but warmer in summer

what temp is mesic soil

8-15 degrees C

what is the most common temp regimes in the US

mesic

what temp is thermic soils

15-22 degrees C

what temp regimes are most common in S. America

thermic

what temp is hyperthermic soil

above 22 degrees C

where is hyperthermic soil found globally and in the US

around the equator and only in flordia

label the numbers

1. order

2. sub-order

3. great-group

4. sub-group

5. family

6. series is given

what are the 7 soil orders of SC

entisols

inceptisols

histosols

mollisols

alfisols

ultisols

spodosols

what are the remaining 5 soil orders not in SC

gelisols

andisols

vertisols

oxisols

aridsols

key factors of entisols

young soils

little to no weathering

PM: sand

most common soil order globally

found around coast

ochric epipedon

key factors of gelisols

permafrost

very cold regions

key factors of andisols

mild weathering on volcanic ejecta

key factors of vertisols

high activity of clays during dry seasons: swelling clays

high base saturation

key factors of aridisols

desert shrubs

found in dry grasslands

key factors of oxisols

most weathered soil

found in wet tropical forest

low activity clays

Fe and Al oxides

what percent of SC soils are entisols

8%

what is the least weathered soil order in SC

entisols

where are entisols found

dunes and steep mountains

what epipedon is seen with entisols

ochric

what diagnostic subsurface horizons are seen with entisols

none

parent material seen with entisols

sand: residuum

what percent of inceptisols make up SC soils

10%

whats the most common soil order in SC

ultisols

what horizons are seen in inceptisols

A, beginning of B’s and C

what epipedon is seen with inceptisols

ochric, some umbic and some mollic

what diagnositic subsurface horizon is seen with inceptisols

Bw and Bg: cambic

PM seen with inceptisols

alluvium

degree of weathering in inceptisols

very saturated but still young and not very weathered