TAMU SCSC 301 Final
After9a9growing9season9of9heavy9tillage9traffic9across9a9soil,9a9soil9property9that9is9least9a
ffected9is:9-9ans-=Particle9density
From9a9biological9point9of9view,9the9most9important9role9of9structural9development9in9clay
ey9textured9soils9is9to9provide9an9increase9in:9-9ans-=macro9porosity
The9purity9of9light9reflected9by9a9soil9is9called:9-9ans-=chroma
A9word9used9to9describe9the9consistence9of9a9soil9is:9-9ans-=plastic
A9soil9horizon9in9which9the9supply9of9gases9is9adequate9for9optimum9biological9activity9is9
said9to:9-9ans-=be9well9aerated
In9a9soil,9having9a9color9of910YR94/1,9the9value9is:9-9ans-=4
10Y9-9hue
19-9chroma
At9a9given9pressure9gradient,9diffusion9is9a9function9of:9-9ans-=total9air9porosity
A9principal9role9of9oxygen9is9soils9is:9-9ans-=oxidation9of9iron
Considering9a9soil9as9a9medium9for9plant9growth9in9terms9of9aeration,9water9supply,9and9t
emperature,9the9most9desirable9structural9type9is:9-9ans-=granular
Under9normal9aerated9conditions,9soil9air9compared9to9the9atmospheric9air9almost9alway
s9contains9the9same9percentage9of:9-9ans-=N2
The9soil9components9-9solids,9solution,9air9-
9arranged9in9order9of9decreasing9heat9capacity9(highest9capacity9first)9are:9-9ans-
=solution,9solids,9air
In9a9clay9loam9soil9horizon9having9a9strongly9developed9fine,9granular9structure,9the9soil9
aeration9is9likely9to9be:9-9ans-=good
Daily9fluctuations9in9temperature9at915cm9below9the9soil9surface,9when9compared9to9dail
y9fluctuations9at92cm9below9the9soil9surface:9-9ans-=occur9later9in9the9day
The9subsoil9is9cooler9than9either9the9surface9soil9or9parent9material:9-9ans-
=in9early9spring
, Water9in9the9soil9is:9-9ans-=a9good9heat9sink
The9rate9of9soil9warming9in9the9spring9at9a9given9location9is9primarily9a9function9of9soil:9-
9ans-=moisture
Water9which9drains9downward9in9a9soil9consists9of9water9which9moves9in9response9to9diff
erences9in:9-9ans-=matric9and9gravitational9potentials
Available9water9in9soils9is9water9held9between9the9wilting9coefficient9and:9-9ans-
=field9capacity
In9a9soil9layer9containing9large9holes9or9channels9open9at9the9surface,9water9enters9the9la
rge9holes:9-9ans-=by9gravity9flow9only
Water9enters9a9very9clayey9subsoil9from9a9sandy9surface9soil:9-9ans-
=as9soon9as9the9wetting9front9reaches9it
A9common9primary9silicate9mineral9which9weathers9to9form9secondary9silicate9minerals9i
n9soils9is:9-9ans-=horneblend
A9typical9moist9surface9soil9contains9approximately919to95%9by9volume9of9____________
.9-9ans-=organic9matter
One9of9the9more9soluble9and9therefore,9easily9weathered9minerals9in9acid9soils9is:9-9ans-
=calcite
A9primary9iron9mineral9that9is9resistant9to9weathering9is:9-9ans-=hematite
Primary9silicate9mineral9resistant9to9weathering9and9dominates9sand/
silt9of9most9soils9is:9-9ans-=quartz
The9properties9of9soil9are9due9to9the9combined9effects9of9__________________,9as9mod
ified9by9relief,9acting9on9parent9material9over9time.9-9ans-=climate9and9biota
A9property9used9in9distinguishing9among9minerals9in9hand9specimen9is:9-9ans-=color
The9two9dimensional9depiction9of9soil9in9a9soil9pit9is9commonly9referred9to9as9a9soil:9-
9ans-=profile
Soils9which9support9aerobic9growth9must9contain:9-9ans-=gaseous9oxygen
A9passive9soil9forming9factor9is:9-9ans-=parent9material9
(and9time)
After9a9growing9season9of9heavy9tillage9traffic9across9a9soil,9a9soil9property9that9is9least9a
ffected9is:9-9ans-=Particle9density
From9a9biological9point9of9view,9the9most9important9role9of9structural9development9in9clay
ey9textured9soils9is9to9provide9an9increase9in:9-9ans-=macro9porosity
The9purity9of9light9reflected9by9a9soil9is9called:9-9ans-=chroma
A9word9used9to9describe9the9consistence9of9a9soil9is:9-9ans-=plastic
A9soil9horizon9in9which9the9supply9of9gases9is9adequate9for9optimum9biological9activity9is9
said9to:9-9ans-=be9well9aerated
In9a9soil,9having9a9color9of910YR94/1,9the9value9is:9-9ans-=4
10Y9-9hue
19-9chroma
At9a9given9pressure9gradient,9diffusion9is9a9function9of:9-9ans-=total9air9porosity
A9principal9role9of9oxygen9is9soils9is:9-9ans-=oxidation9of9iron
Considering9a9soil9as9a9medium9for9plant9growth9in9terms9of9aeration,9water9supply,9and9t
emperature,9the9most9desirable9structural9type9is:9-9ans-=granular
Under9normal9aerated9conditions,9soil9air9compared9to9the9atmospheric9air9almost9alway
s9contains9the9same9percentage9of:9-9ans-=N2
The9soil9components9-9solids,9solution,9air9-
9arranged9in9order9of9decreasing9heat9capacity9(highest9capacity9first)9are:9-9ans-
=solution,9solids,9air
In9a9clay9loam9soil9horizon9having9a9strongly9developed9fine,9granular9structure,9the9soil9
aeration9is9likely9to9be:9-9ans-=good
Daily9fluctuations9in9temperature9at915cm9below9the9soil9surface,9when9compared9to9dail
y9fluctuations9at92cm9below9the9soil9surface:9-9ans-=occur9later9in9the9day
The9subsoil9is9cooler9than9either9the9surface9soil9or9parent9material:9-9ans-
=in9early9spring
, Water9in9the9soil9is:9-9ans-=a9good9heat9sink
The9rate9of9soil9warming9in9the9spring9at9a9given9location9is9primarily9a9function9of9soil:9-
9ans-=moisture
Water9which9drains9downward9in9a9soil9consists9of9water9which9moves9in9response9to9diff
erences9in:9-9ans-=matric9and9gravitational9potentials
Available9water9in9soils9is9water9held9between9the9wilting9coefficient9and:9-9ans-
=field9capacity
In9a9soil9layer9containing9large9holes9or9channels9open9at9the9surface,9water9enters9the9la
rge9holes:9-9ans-=by9gravity9flow9only
Water9enters9a9very9clayey9subsoil9from9a9sandy9surface9soil:9-9ans-
=as9soon9as9the9wetting9front9reaches9it
A9common9primary9silicate9mineral9which9weathers9to9form9secondary9silicate9minerals9i
n9soils9is:9-9ans-=horneblend
A9typical9moist9surface9soil9contains9approximately919to95%9by9volume9of9____________
.9-9ans-=organic9matter
One9of9the9more9soluble9and9therefore,9easily9weathered9minerals9in9acid9soils9is:9-9ans-
=calcite
A9primary9iron9mineral9that9is9resistant9to9weathering9is:9-9ans-=hematite
Primary9silicate9mineral9resistant9to9weathering9and9dominates9sand/
silt9of9most9soils9is:9-9ans-=quartz
The9properties9of9soil9are9due9to9the9combined9effects9of9__________________,9as9mod
ified9by9relief,9acting9on9parent9material9over9time.9-9ans-=climate9and9biota
A9property9used9in9distinguishing9among9minerals9in9hand9specimen9is:9-9ans-=color
The9two9dimensional9depiction9of9soil9in9a9soil9pit9is9commonly9referred9to9as9a9soil:9-
9ans-=profile
Soils9which9support9aerobic9growth9must9contain:9-9ans-=gaseous9oxygen
A9passive9soil9forming9factor9is:9-9ans-=parent9material9
(and9time)
