Which group of soil organisms includes the largest number of autotrophic species?
A) fungi
B) actinomycetes
C) protozoa
D) bacteria
E) detritivores
Question 2Compared to the bulk soil in which the earthworms live, earthworm casts contain ________.
A) less organic matter
B) more of most plant-available nutrients
C) less of most plant-available nutrients
D) more sand and silt
E) more nitrogen but less of other plant-available nutrients
Question 3If you want to grow azaleas in a soil that initially has a pH of 6.5 and have been told that you should apply sulfur to reduce the soil pH, you would likely need more sulfur if the soil is a clay Vertisol than if it is an clay Ultisol.
Indicate whether the statement is true or false
Question 4Which of the following groups of organisms are responsible for greatest amount of organic matter decomposition in soils?
A) macrofauna B) microflora C) mesofauna D) microfauna E) autotrophs
Question 5An organism that subsists by eating predators would function as a(n) ________ in the soil ecosystem
A) decomposer
B) primary consumer
C) tertiary consumer
D) detritivore
E) all of the above
Question 6Soil detritivores feed principally on ________.
A) larger, but defenseless animals
B) dead tissues
C) microorganisms
D) smaller organisms
E) plant roots