dirt asf

Hans Jenny

first person with a formula to describe soil

Guy Smith

produced the 1st of 7 iterations of soil taxonomy

Karl Terzaghi

father of soil mechanics

Peter Birkeland

connected soil and geomorphology

Robert Ruhe

using soils to understand glacial episodes

Cullen Sherwood

helped form the JMU geology department

_____ ______ a two-dimensional body, commonly studied in artificial cuts

Soil profile

____ ____: a three-dimensional body, with the same thickness as a profile but w a surfacr area that ranges between 1 and 100 square meters

soil pedon

soil dimension layers

OAEBCR

Major components of soil: _____ _____ (5%), ______ (45%), _____ (25%), and ____ (25%)

organic materials, minerals, water, air

____: consists of the surface and subsoil layers that have same soil forming conditions (_____ layers)

solum, oaeb

___ horizon: zone of leaching/removal

OAE

____ horizon: zone of accumulation

B

____ horizon: weathered parent material

C

___ horizon: super leeched, mostly quartz and sand grains, from developed soil

E

___ horizon: residuum (parent material)

R

____ horizon: plowed soil

Ap

____ horizon: translocation of clay (mature soil)

Bt

____ horizon: weak/juvenile horizon

Bw

_____ horizon: calcite rich (or carbonates)

Bk

____ horizon: fragipan soil, poor drainage, soils have X pattern

Bx

clay is common in __ horizons

B

silty loam is common in ___ horizons

A

Loam is common in ___ horizons over granites

A

texture is important in soils work as it reflect character of ____ ____, and affects ____ within the soil ( like drainage, horizon development, etc.)

parent material, processes

soil processes examples

degree of horizon development, drainage properties, engineering properties, degree of chemical reactivity, water retention, erosivity, and tilth

_____: actual color of the soil relative to the primary colors (first part of munsell color chart)

hue

_____: lightness or darkness of color (8 will very light, 2 is dark) (____/chroma for munsell color chart)

value

_____ or ____ features: show presence of long standing water

mottles, redox

_____: aggregation of soil particles

peds

A horizon structure types: _____ and ____

loose/granular, crumb

Bt horizon types: _____ _____and _____ _____, or _____ (salty soils)

angular blocky, subangular blocky, prismatic

____ ____ in soil increase water holding capacity and tilth, increases cation exchange capacity

organic matter

Vasily V Dokuchaev

father of modern soil science

How soils form

parent material (R) layer, surface organic increase (A,C), clay increase in B horizon (ABC)

______ ____: some layers are more resistant to weathering and some aren't (chunks of bedrock, soil not even depth)

pinnacle weathering

soils over igneous rocks (granite edition- on piedmont & blue ridge)

sandy A horizon, strong B horizon, saprolite base layer

______: residuum that has the appearance of rock but some properties of soil

saprolite

___: granites that weather to saprolite

grus

gabbro soil characteristics (piedmont)

heavy clay soils, shallow profiles, SOUPY!!

limestone and dolomite soils characteristics (valley and ridge) (this is harrisonburg!)

deep, well drained, clay-rich, productive

shale (sedimentary) rock soil characteristics

shallow, immature, low nutrients

sandstone (sedimentary) rock soil characteristics

shallow profile, excessively drained, sandy textures

floodplain soil characteristics (alluvium transported soil)

young sandy soil, moist, productive, poor horizon development

terrace soil characteristics (alluvium transported soil)

varying ages/development, friable, productive

base of steep slope soil characteristics (colluvium soil)

thick, moist, weak profile development

debris/alluvial fan soil characteristics (colluvium soil)

thick moist, weak profile development, productive

loess soil characteristics (from aeolian (wind) processes)

high silt, weak to moderate profile development, productive but highly errosive

glacial till soil characteristics (glacial processes)

highly dependent on mode of deposition, weak profile development, often rocky thin profiles

_____ is the most important factor in soil development on a global scale

climate

microclimate soil processes include: _____, _______, _____; these can control local moisture and temperature conditions

exposure, boulder, hillside

______ ____: affects soil formation by type of material (most rocks have low conductivity), moisture, albedo (light reflection), depth of frost

heat conductivity

______: affects soil formation as it can provide coolness and moisture

vegetation

_______: (moisture regime) soils of temperate areas that experience moist winters and dry summers, mediterranean climates

xeric

________/______: (moisture regime) soils are dry more than half the time

aridic, torric

______: (moisture regime) in most years soils are dry for 90+ days and moist in some part for half the days the temp is above 5C

ustic

_____: (moisture regime) in most yeawrs soils are not dry more than 90 consecutive days

udic

______: (moisture regime) in most years precipitation exceeds evapotranspiration every month of the year

perudic

_____: soils are sufficiently saturated, usually reduced and mottles or gleyed

aquic

soil temperature regime range (from really hot to really cold)

hyperthermic, thermic, mesic, frigid, cryic, pergelic

(old zonal system) _____ soil west of missippi and ______ east of missippi

pedocals, pedalfers

________: (recent) soil on flooplains, little to no horizon development, usually no B horizon, pretty infertile, YOUNGEST SOIL

entisol

_______: (beginning) upland soil, weak horizon development, thin B horizon, common on steep slopes esp. shales

inceptisol

______: (last) acidic leached soils of warm humid climtes, B horizon w claysssss, sometimes has E horizon, frederick soil series, pretty (lowkey the most developed) ngl

ultisols

____: (Al and Fe concentrations) strong Bt horizon, full of Al and Fe, high base saturation, heart of corn belt and pretty fertile, less oxidation

alfisols

____: (oxide) oxidized tropical soils, highly weathered and pretty infertile

oxisols

______: (soft) base-rich soils that have thick dark A horizons, usually in savannas/steppes, black fertile and high in organics, high in silt, feeds 75% of the world

mollisol

_____: (dry) soils of dry climates w some B horizon, low organics but high fertility, found in cold and hot deserts, similar to ultisols but lacks moisture

aridisols

______: absorbs water with lots of salts but water evaporates and leave layers of minerals behind, common with aridisols

caliche

______: (to turn/mix) dark soils of semi-arid grasslands and savannas, high in clay, dark because lack of oxidation

vertisol

______: (wood ash) soils common in new england, has a layer of sandy ash on top

spodosol

______: (tissue) organic soils without shallow permafrost, sooooooo much decomposing organic matter, just gobs of plants

histosol

____: (to freeze) soil with permafrost below A horizon, leached low nutrients

gelisols

_____: soils that have often formed in parent material with a large component of volcanic ash, most common in PNW

andisols

_______ _____: slope factor dictates what soil will be present in a landscape

soil catena

_______ are similar to inceptisols but has a weaker horizon

andisols

_______ are close to ultisols but lack moisture

aridisols

_____ are close to ultisols but are as developed as ultisols (ultisols more leached and acidic)

alfisols

alfisol, andisol, ardisol, entisol, gelisol, histosol, inceptisol, mollisol, oxisol, spodosol, ultisol, vertisol

entisol

inceptisol

ultisol

alfisol

mollisol

aridisol

vertisol

spodosol

histosol

andisol

gelisol

oxisol