Exam 3 SCSC

Aquic

saturated with water, poor aeration

Udic

high moisture year round

Ustic

adequate moisture, some periods of drought

Aridic

dry for at least half the growing season

Xeric

wet winters, dry summers, seasonal moisture

superclass problem w

wet

superclass problem e

erosion

superclass problem s

shallow

superclass problem c

climate

landuse capability class

ranked from I to VIII

V, VI, VII, VIII

not suitable for cultivation

Oi

fibric, slightly decomposed

Oe

hemic, moderately decomposed

Oa

sapric, highly decomposed

Ap

plowing

Bw

no accumulation, weakly weathered

Bt

accumulation of clay

Bo

accumulation of Fe and Al oxides

Bhs

accumulation of humus, Fe and Al oxides

Btn

accumulation of clay and sodium

Bk

accumulation of carbonates

By

accumulation of gypsum

Bss

presence of slickensides

Cr

soft bedrock

qualities inherited from parent material

mineralogy, texture, pH, stratification

qualities acquired by soil formation processes

structure, organic matter, horizonation

Albic

E

Cambic

Bw

Argillic

Bt

Kandic

Bt, Bts

Oxic

Bo

Spodic

Bhs

Calcic

Bk

Gypsic

By

erosion

transformation of soil into sediment

on-site damage

loss of soil, remaining soil is lower quality

off-site damage

water quality impairment, increased road and drain maintenance, health hazards from breathing small particles

sheet erosion

thin layer of surface removed

rill erosion

small channels on the side of a slope

gully erosion

deep and wide channel

soil creep

the extremely slow downhill slide of soil (5-25%)

soil saltation

soil particals hopping (50-90%!!)

soil suspension

soil particles in the air

mass flow

movement due to different total pressure

diffusion

movement due to difference in partial pressure

soil aeration

the movement of air into the soil

soil is

anaerobic (operates without oxygen)

improve aeration

improve aggregation, improve drainage, reduce compaction, tillage

wet soils require

more energy to heat than dry soils

specific heat

amount of energy it takes to raise T by 1 degree C/g

thermal conductivity

rate of heat transfer through soil

wet, compacted soil is the best

conductor

dry soils are

good insulators

larger depth soil

takes longer to heat up

oxygen availability is regulated by

macroporosity, water content, respiration rate

redox

transfer of electrons

redox potential

the tendency of electrons to be transferred

oxidizing agent, oxygen

electron acceptor

reducing agent

electron donor