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ECOL111 EXAM Questions with Answers (100% Correct
Answers)
Evapotranspiration Answer: The process by which water moves from
the earth to the atmosphere by evaporation and transpiration from
plants.
Aridity Index (AI) Answer: The ratio of precipitation and potential
evapotranspiration (AI = precipitation/potential evapotranspiration).
The smaller the number, the greater the aridity.
Why are drylands important for carbon storage? Answer: They are
extensive, stable, and able to sequester large amounts of carbon for a
long time.
What are the four major constituents of water potential? Answer:
Osmotic potential, turgor potential, gravitational potential, metric
potential.
Osmotic Potential Answer: Energy associated with dissolved solutes -
salt water has a lower potential than fresh water.
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Turgor Potential Answer: Energy associated with the exertion of
pressure - water moves from high pressure to low pressure.
Gravitational Potential Answer: Energy associated with gravity - water
flows downslope.
Matric Potential Answer: Energy associated with attractive forces
between molecules - e.g surface tension, capillary action, soil-bound
water.
Niche differentiation Answer: Differentiation in multiple niche
dimensions is what allows species to coexist given competitive
exclusion.
Competitive exclusion Answer: If two species occupy the same niche,
one will be better at exploiting the most limiting resource and
eventually exclude the other.
Water potential Answer: the potential energy of water per unit volume
relative to pure water.
Hydrological niche example Answer: Cape Flora, SA. Water
availability for plants is linked to soil drainage as well as bioclimatic
factors.
© 2025 All rights reserved
ECOL111 EXAM Questions with Answers (100% Correct
Answers)
Evapotranspiration Answer: The process by which water moves from
the earth to the atmosphere by evaporation and transpiration from
plants.
Aridity Index (AI) Answer: The ratio of precipitation and potential
evapotranspiration (AI = precipitation/potential evapotranspiration).
The smaller the number, the greater the aridity.
Why are drylands important for carbon storage? Answer: They are
extensive, stable, and able to sequester large amounts of carbon for a
long time.
What are the four major constituents of water potential? Answer:
Osmotic potential, turgor potential, gravitational potential, metric
potential.
Osmotic Potential Answer: Energy associated with dissolved solutes -
salt water has a lower potential than fresh water.
© 2025 All rights reserved
, 2
Turgor Potential Answer: Energy associated with the exertion of
pressure - water moves from high pressure to low pressure.
Gravitational Potential Answer: Energy associated with gravity - water
flows downslope.
Matric Potential Answer: Energy associated with attractive forces
between molecules - e.g surface tension, capillary action, soil-bound
water.
Niche differentiation Answer: Differentiation in multiple niche
dimensions is what allows species to coexist given competitive
exclusion.
Competitive exclusion Answer: If two species occupy the same niche,
one will be better at exploiting the most limiting resource and
eventually exclude the other.
Water potential Answer: the potential energy of water per unit volume
relative to pure water.
Hydrological niche example Answer: Cape Flora, SA. Water
availability for plants is linked to soil drainage as well as bioclimatic
factors.
© 2025 All rights reserved
