Plants in Dry Environments
In dry environments, plants keep their stomata closed to limit
water loss
yet they must open their stomata to exchange gases with the
environment.
In dry environments, there is a also a physical increase in
evaporation.
Plants heat up faster and need to open their stomata to cool off.
Plants deal with a dry environment in the following ways:
·Time their growth season to match the rainy season.
·Accumulate solutes in the cell (by changing their osmotic potential).
This way a
plant improves its ability to pull water from the ground/soil.
·Develop a waxy cuticle
·Regulate stomata openings so that they open at night
(These plants are called CAM
plants).
·Temporarily reduce the surface area of their leaves
Corn plants do this. This
reduces the rate of evaporation.
·Only produce leaves during periods of heavy rain.
·Change leaf orientation to reduce evaporation.
·Store water succulents.
*Also, different root systems enable a plant to adapt to dry environments.
Deep tap
roots are useful for collecting lots of water deep in the earth.
A dense, shallow
root system is useful when there is heavy competition among plants.