If a Dry Soil High in Certain Types of ____

question 6

Multiple Choice

If a dry soil high in certain types of ____ is moistened,it is likely to swell up with enough force to crack pavements and building foundations.

• A)humus
• B)iron
• C)clay
• D)silt
• E)any of the above

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Definitions:

Competitive Exclusion

A principle stating that two species competing for the same limiting resources cannot coexist at constant population values.

Character Displacement

The phenomenon where differences among similar species whose distributions overlap geographically are accentuated in regions where the species co-occur, but are minimized or lost where the species' distributions do not overlap.

Primary Succession

An ecological succession that occurs on land that has not previously been inhabited by plants; no soil is present initially. See succession. Compare with secondary succession.

Zooplankton

The nonphotosynthetic organisms present in plankton (e.g., protozoa, tiny crustaceans) and the larval stages of many animals. See plankton. Compare with phytoplankton.