SCSC 301 LATEST EXAM 2026/2027 QUESTIONS AND
SOLUTIONS RATED A+
✔✔Aridic - ✔✔Dry for at least half of growing season. Moist for less than 90 consecutive
days
✔✔Xeric - ✔✔- Cool, wet winters and warm, dry summers
- DOES NOT MEAN NO RAIN, it means SEASONAL RAIN
✔✔example name:
Houston Black series: Fine, smectic, thermic udic Haplustert - ✔✔order- vertisol
suborder- ustert
great- haplustert
subgroup- Udic Haplustert
family- whole name
series- Houston Black
✔✔b - ✔✔Buried Soil horizon
✔✔f - ✔✔Frozen soil
✔✔ff - ✔✔Dry permafrost
✔✔g - ✔✔strong gleying (mottling)
✔✔jj - ✔✔Cryotubation (frost churning)
✔✔m - ✔✔Cementation or induration
✔✔n - ✔✔accumulation of sodium
✔✔x - ✔✔fragipan (high bulk density, brittle)
✔✔temperature regimes - ✔✔hyperthermic, thermic, mesic, frigid, cryic, gelic
✔✔this soil has been the least impacted by leaching (think arid) - ✔✔A-Bk-By-Bz-C
✔✔what is the primary epipedon for a spodisol - ✔✔ochric
✔✔what are the dominate endopedons for a spodisol - ✔✔Albic, Spodic
✔✔hydrologic cycle - ✔✔powered by the sun
✔✔water balance equation - ✔✔P = ET + SS + D
, ✔✔ET of water balance - ✔✔depends on vegetation, soil cover, temp, humidity
✔✔SS of water balance - ✔✔Depends on infiltration rate, soil moisture state,
topography, microrelief
✔✔Runoff - ✔✔affects ET
✔✔How to encourage infiltration - ✔✔cover crops, conservation tillage, strip cropping,
furrow dikes, contour rows, terraces, increase OM, subsurface drainage
✔✔PET - ✔✔amount of water vapor that would be lost from a densely vegetated soil if
soil water content were optimum
✔✔What does PET depend on - ✔✔Temp, Relative humidity, cloud cover, wind
✔✔Transpiration efficiency - ✔✔Dry matter yield / Unit water lost to T
✔✔ET efficiency - ✔✔dry matter yield per unit of water lost to evapotranspiration
✔✔Transpiration ratio - ✔✔Kg water transpired to produce 1 Kg of dry matter
✔✔Control ET - ✔✔manage crop, irrigation, limit plant nutrients, sow fewer seets, plant
shading, eliminate weeds, mulch
✔✔Leaching - ✔✔solubility, texture, frequency anf mount of percolate, pH, fertility status
✔✔consequences of excess runoff to water - ✔✔eutrophication
✔✔removing excess water surface can... - ✔✔handle large volumes, low installation
cost, more prone to erosion, high maintenance cost
✔✔removing excess water subsurface can... - ✔✔provide percolation, low maintenance
cost, high rainfall can lead to flooding/ leaching, high installation cost
✔✔Soil Air CO2 amounts - ✔✔Higher than atmosphere
✔✔Soil Air O2 amounts - ✔✔lower than atmosphere
✔✔what role does O2 play in soil - ✔✔provides to respiring organisms
✔✔macroporosity - ✔✔more macropores= more easily O2 can be replenished= more
O2 abailable
SOLUTIONS RATED A+
✔✔Aridic - ✔✔Dry for at least half of growing season. Moist for less than 90 consecutive
days
✔✔Xeric - ✔✔- Cool, wet winters and warm, dry summers
- DOES NOT MEAN NO RAIN, it means SEASONAL RAIN
✔✔example name:
Houston Black series: Fine, smectic, thermic udic Haplustert - ✔✔order- vertisol
suborder- ustert
great- haplustert
subgroup- Udic Haplustert
family- whole name
series- Houston Black
✔✔b - ✔✔Buried Soil horizon
✔✔f - ✔✔Frozen soil
✔✔ff - ✔✔Dry permafrost
✔✔g - ✔✔strong gleying (mottling)
✔✔jj - ✔✔Cryotubation (frost churning)
✔✔m - ✔✔Cementation or induration
✔✔n - ✔✔accumulation of sodium
✔✔x - ✔✔fragipan (high bulk density, brittle)
✔✔temperature regimes - ✔✔hyperthermic, thermic, mesic, frigid, cryic, gelic
✔✔this soil has been the least impacted by leaching (think arid) - ✔✔A-Bk-By-Bz-C
✔✔what is the primary epipedon for a spodisol - ✔✔ochric
✔✔what are the dominate endopedons for a spodisol - ✔✔Albic, Spodic
✔✔hydrologic cycle - ✔✔powered by the sun
✔✔water balance equation - ✔✔P = ET + SS + D
, ✔✔ET of water balance - ✔✔depends on vegetation, soil cover, temp, humidity
✔✔SS of water balance - ✔✔Depends on infiltration rate, soil moisture state,
topography, microrelief
✔✔Runoff - ✔✔affects ET
✔✔How to encourage infiltration - ✔✔cover crops, conservation tillage, strip cropping,
furrow dikes, contour rows, terraces, increase OM, subsurface drainage
✔✔PET - ✔✔amount of water vapor that would be lost from a densely vegetated soil if
soil water content were optimum
✔✔What does PET depend on - ✔✔Temp, Relative humidity, cloud cover, wind
✔✔Transpiration efficiency - ✔✔Dry matter yield / Unit water lost to T
✔✔ET efficiency - ✔✔dry matter yield per unit of water lost to evapotranspiration
✔✔Transpiration ratio - ✔✔Kg water transpired to produce 1 Kg of dry matter
✔✔Control ET - ✔✔manage crop, irrigation, limit plant nutrients, sow fewer seets, plant
shading, eliminate weeds, mulch
✔✔Leaching - ✔✔solubility, texture, frequency anf mount of percolate, pH, fertility status
✔✔consequences of excess runoff to water - ✔✔eutrophication
✔✔removing excess water surface can... - ✔✔handle large volumes, low installation
cost, more prone to erosion, high maintenance cost
✔✔removing excess water subsurface can... - ✔✔provide percolation, low maintenance
cost, high rainfall can lead to flooding/ leaching, high installation cost
✔✔Soil Air CO2 amounts - ✔✔Higher than atmosphere
✔✔Soil Air O2 amounts - ✔✔lower than atmosphere
✔✔what role does O2 play in soil - ✔✔provides to respiring organisms
✔✔macroporosity - ✔✔more macropores= more easily O2 can be replenished= more
O2 abailable
