Midterm 2

Question 1

True or false: Fungi are much MORE sensitive to strong acid conditions than bacteria or actinomycetes.

Answer 1

false

Question 2

Which of the following human actions results in a long-term increase in soil pH?

Answer 2

irrigation with high sodium salt-containing waters

Question 3

Which statement about plants using C4 pathways is FALSE?

Answer 3

their stomata are closed during the day and open during the night.

Question 4

True or false: a tree that lives for more than one year is known as an “evergreen” tree.

Answer 4

false

Question 5

What kind of trees of the temperate climate zone dominate in montane (high elevation) regions and
on nutrient-poor sandy soils?
[Hint: These trees also dominate the temperate rainforest of the U.S. Pacific Northwest.]

Answer 5

evergreen needle-leaf

Question 6

Plants adapted to low-nutrient environments are characterized by

Answer 6

increased leaf longevity

Question 7

Graphs showing number of seeds per stem vs mean weight and Body mass vs litter size
These data support the trade-off that

Answer 7

size of offspring is correlated with number of offspring

Question 8

The nomenclature of Soil Taxonomy is characterized by all but which?

Answer 8

the names give a clear indication of the modes of genesis of the soil

Question 9

The demographic age pyramid of a rapidly growing population is

Answer 9

wide at the base, narrow at the top

Question 10

A population that is increasing in size has an intrinsic rate of population growth (r) that is

Answer 10

> 0

Question 11

True or false: You would expect the cation exchange capacity of Alfisols to be greater than that of Ultisols if the soil textures are about the same.

Answer 11

True

Question 12

As population size (N) increases, the per capita

Answer 12

the birth rate decreases and the death rate increases

Question 13

In which soil order would you find a soil with a master horizon sequence O-A-C?

Question 14

True or false: a soil with an ochric epipedon could generally be expected to be more strongly weathered than one with an umbric epipedon.

Answer 14

false

Question 15

In populations of animals that defend an area for their own exclusive use or in plants that compete intensively for belowground resources such as water or nutrients, the spatial distribution of individuals is usually

Answer 15

uniform

Question 16

Which of the following is a density dependent factor that may limit the growth of a population?

Answer 16

shelter availability

Question 17

Which photosynthetic pathway is shown?
Mesophyll and bundle sheath cell.
Organic acid -> CO2 -> Calvin cycle

Answer 17

C4

Question 18

Plants can rapidly reduce water loss by

Answer 18

closing their stomata

Question 19

Investigating the soils of northern Canada one summer, you dig a soil pit easily through fairly uniform peat material until, at 75 cm deep, your shovel hits a layer that is frozen solid. Into which type of soil are you most likely digging?

Answer 19

Histel

Question 20

True or false: intraspecific competition affects the populations of two or more species adversely and is a cornerstone of evolutionary ecology. Ecologists distinguish exploitation and interference.

Answer 20

false

Question 21

Match the soil pH to its properties
pH 7-8.5
pH 5-7
pH <3.5

Question 22

The dark reactions of photosynthesis use ___ and produce ____

Answer 22

NADPH
sugars CHECK THIS ONE IDK

Question 23

the soil is covered by a hard, white crust, and plant growth is suppressed

Answer 23

salinity; salty water has evaporated from the surface, and the soil water has a high sodium content and electrical conductivity

Question 24

the soil has a pH >8.5, low electrical conductivity (<4 dS/m), and there are signs of erosion (subsidence, gullies)

Answer 24

sodicity; the cation exchange capacity of the soil is dominated by exchangeable sodium

Question 25

Explain why the availability of the plant macronutrient phosphorus is low in both acidic (<pH 5.5) and alkaline (>7) soils, and commonly limits the productivity of terrestrial ecosystems. [Assume that phosphorus is present in the parent material.]

Answer 25

Phosphorus is not available at low and high pH because at low pH it is combined with Al and in high pH it is with calcium. It doesn’t like to be in solution, it likes to be in a solid form so the plants can’t use it.

Question 26

State factor that best explains distribution of histosols,vertisols, and andisols

Question 27

State factor that best explains distribution of gelisols, oxisols

Answer 27

climate

Question 28

State factor that best explains distribution of entisols and ultisols

Answer 28

time

Question 29

Plants adapted to growing in the shady understory of a forest tend to have a _____ light compensation point than plants that make up the upper (sunnier) canopy of the forest.

Answer 29

lower

Question 30

Soils with organic materials extending down to an impermeable layer

Answer 30

Histols

Question 31

Soils with permafrost within 100 cm

Answer 31

Gelisols

Question 32

Soils with 30% or more clay to 50 cm and shrinking/swelling properties

Answer 32

Vertisols

Question 33

Soils formed on volcanic ash rich in amorphic/short-range-order minerals such as allophane and ferrihydrite

Answer 33

Andisols

Question 34

Oxygen is produced from [molecule] during the light reactions of photosynthesis.

Answer 34

water

Question 35

forest die-back due to acid rain

Question 36

death of aquatic communities due to the drainage of extremely acid waters (acid mine drainage)