Soil orders

Question 1

characteristics of Vertosols

Answer 1

High shrink swell clays
prone to cracking and waterlogging
typically high in natural fertility

Constraints: waterlogging, structural issues due to shrink swell
difficult to work when wet and are hard when dry

Question 2

Charcteristics of tenosols

Answer 2

sandy soils
formed from recently weathered materials
physically unstable
low in fertility
Major constraints:
low nutrient retention due to low CEC
erosion risk b/c structureless
poor water holding capacity

Question 3

Characteristics of Ferrosols

Answer 3

Deep, well structure soils with high Fe/Al oxide content
high fertility but high P fixing b/c of oxides
common in high rainfall areas
formed from deeply weathered balsalt/felsic parent material
Constraints:
high P fixing means P is unavailable to plants
typically strongly acidic, leading to Al toxicity and reduce availability of other nutrients such as Ca, Mg and Mo
high rainfall leading to leaching

Question 4

Characteristics of dermosols

Answer 4

moderately strongly structured with loamy topsoils
high organic matter
neutral/ slightly acidic
good fertility and drainage
found on volcanic landscapes and floodplains
Major constraints:
strongly acidic topsoil, leading to Al tox and P fixation
clay subsoils can impede water movement
erosion risk

Question 5

Characteristics of sodosols

Answer 5

Sodic B horizons, leading to dispersive forces and poor structure
poor infiltration and drainage
major constraints:
sodicity, leads to dispersion and poor structure
dispersion of fine particles leads to crusting and reduces water infiltration
high pH- micronutrient deficiency and reduced P availability
salinity- increases root stress

Question 6

Characteristics of calcarosols

Answer 6

high in carbonates
alkaline pH
sandy loams
low fertility and water holding capacity
subsoil sodicity common
major constraints:
alkalinity leads to micronutrient deficiency and P deficiency b/c CaPO4
low organic matter and fertility
erosion risk

Question 7

Characteristics of Organosols

Answer 7

High organic matter
highly acidic and poorly drained
Major Constraints:
waterlogging- lack of O2 and anaerobic conditions can lead to reduced forms of N which are toxic
acidity- due to waterlogging forming organic acids
low bulk density making soils unstable for machinery

Question 8

Characteristics of Podosols

Answer 8

strongly leached
acidic
Bleached B horizons
accumulation of Fe and Al organic complexes
Low fertility
major constraints:
Al toxicity and reduced availability of nutrients
strong leaching leading to nutrient deficiency
poor structures due to sandy textures also leading to poor water capacity
erosion risk b/c sandy