1. one of the most important environmental limiting factors for plants
PLANTS AND WATER
one of the most important environmental limiting factors for plants
© 2016 Paul Billiet ODWS

2. Hydrophytes Plants adapted to excessive amounts of water
Elodea canadensis
© 2016 Paul Billiet ODWS
© P Billiet

3. Mesophytes Plants adapted to moderate amounts of water
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Ranunculus ficaria
© 2016 Paul Billiet
ODWS

4. Xerophytes Plants adapted to low amounts of water Eryngium maritimum
Eryngium maritimum
© 2016 Paul Billiet ODWS

5. Halophytes Plants which can grow in salty environments.
Salicornia europaea
Plants which can grow in salty environments.
Water may be abundant but because of osmotic forces it may be unobtainable to the plant tissues without special adaptations
© 2016 Paul Billiet ODWS

6. Hydrophytes © 2016 Paul Billiet ODWS
© 2016 Paul Billiet ODWS

7. Hydrophytes © 2016 Paul Billiet ODWS
© 2016 Paul Billiet ODWS

8. Xerophytes Plants which live in arid environments
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Plants which live in arid environments
© 2016 Paul Billiet ODWS

9. Xerophytes Reduced leaf surface Rolled leaves © 2016 Paul Billiet ODWS
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Reduced leaf surface
Rolled leaves
© 2016 Paul Billiet ODWS

10. Xerophytes Water storing tissues © 2016 Paul Billiet ODWS © P Billiet

11. Xerophytes
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Ilex aquifolium
Waxy leaves

12. Xerophytes Reduced leaf surface Reduced number of stomata
The stomata are often sunken in pits to prevent water vapour from being blown away
Grasses may roll their leaves up to enclose their stomata in the same way
A thick waxy cuticle
Succulent tissue which can store large amounts of water
They may have an extensive rooting system
© 2016 Paul Billiet ODWS

13. Xerophytes
They may able to withstand an excessive desiccation of their tissues
A metabolism which permits them to open their stomata at night and combine CO2 with organic acids in the dark
Crassulation Acid Metabolism or CAM
C4 plants have evolved an enzyme which fixes CO2 with organic acids
This enzyme has a higher affinity for CO2 than Rubisco
These plants can photosynthesis with stomata that are not so wide open as the normal plants (C3 plants), reducing water loss
© 2016 Paul Billiet ODWS