NRES 201 Exam 2 Quizzes

the hydrometer method determines —

a. texture

soils of this textural class have a high water holding capacity but are poorly drained

c. clay loam

As a soil property, — density is much more variable than — density

a. bulk, particle

bulk density is the lowest for this order

c. histosols

owing to a more limited presence of porous aggregates, bulk density if the highest for this textural class

a. sandy loam

The B horizon is typically — than the A horizon in — density

c. higher, bulk

soil compaction increases — but not — density

a. bulk, particle

a higher — density, — porosity

d. bulk, decreases

aeration and drainage are often more limited for the subsoil than the surface soil due to lower — porosity and higher — porosity.

a. macro, micro

By depleting soil organic matter, tillage has the long term effect of — aggregate stability

b. decreasing

by enhancing infiltration, soil organic matter — erosion

b. decreases

during residue decomposition, bacteria and fungi convert — to —

a. Organic C, CO2

decomposition is more rapid for residues with a — C/N ratio

b. low

rising levels of atmospheric CO2 are due in part to depletion of soil organic matter

a. true

capillary rise is the highest for this textural class

c. clay loam

soil water potential — as the soil dries

b. decreases

soil water content is highest at —

a. field capacity

tensiometers measure soil water —

b. potential

saturated flow is most rapid for this textural class

a. sandy loam

soil drainage occurs by — flow

a. saturated

Most of the Earth’s water is found in the —

c. hydrosphere

clear-cutting a forested watershed will increase the discharge of water due to reduction in

b. evapotranspiration

a greater proportion of precipitation will be lost by transpiration

a. deciduous forest

the rationale for keeping land fallow is to control water loss by —

c. transpiration

Most of the agricultural land under irrigation is located in the — USA

b. Western

This type of irrigation educes the amount of water applied

c. drip

Subsurface tile drainage lowers the water table by removing — water from the soil profile

a. gravitational

soil aeration mainly occurs by —

b. diffusion

Redox potential — when a soil is waterlogged

b. decreases

Due to higher temperatures, microbial production of — poses a greater limitation for soil aeration in the summer compared to early spring

b. CO2