B.F. Bachelor of Forestry Forest Soils 2

Question 1

Which macronutrient is most commonly limiting to tree growth in boreal and many temperate forest soils?

Accepted Answer

Nitrogen

Answer

Phosphorus

Answer

Potassium

Answer

Calcium

Question 2

What type of symbiotic association do most conifers and many hardwoods form with soil fungi to enhance nutrient uptake?

Accepted Answer

Mycorrhizae

Answer

Rhizobium nodules

Answer

Actinomycete associations

Answer

Lichen partnerships

Question 3

What is humus?

Accepted Answer

Stable, well-decomposed organic matter that improves soil structure and fertility

Answer

The partially decomposed layer of fresh leaf litter at the soil surface

Answer

The living microbial biomass within the soil matrix

Answer

A type of clay mineral common in temperate forest soils

Question 4

Which biological process converts atmospheric nitrogen (N₂) into plant-available ammonium in forest soils?

Accepted Answer

Nitrogen fixation

Answer

Denitrification

Answer

Nitrification

Answer

Ammonification

Question 5

How does soil compaction from heavy logging equipment primarily affect forest regeneration?

Accepted Answer

It reduces soil porosity, limiting root penetration and water infiltration

Answer

It increases soil temperature and promotes seed germination

Answer

It increases nutrient availability by breaking up organic matter

Answer

It improves drainage and reduces waterlogging risk

Question 6

What is the primary role of the soil food web in nutrient cycling within forest ecosystems?

Accepted Answer

It decomposes organic matter and releases nutrients into plant-available forms

Answer

It mineralizes nutrients from inorganic compounds through chemical weathering

Answer

It fixes atmospheric gases and incorporates them into the soil

Answer

It transports nutrients from deep soil layers upward to the surface

Question 7

What is the process called by which organic nitrogen is converted to ammonium (NH₄⁺) in forest soils?

Accepted Answer

Ammonification

Answer

Nitrification

Answer

Denitrification

Answer

Volatilization