Xerophytes are plants which are adapted to dry/desert areas. To survive these harsh conditions they have special features. For example, a cactus has white hairs which help to prevent water loss. Another example is manzanita plants, which have a thick waxy coating and keep their leaves vertical to the sun.
Adaptions[change | change source]
Some Xerophytic plants sit out a drought. They can still extract water from soil. They may have very salty cell sap and therefore a very low water potential in the roots; they may have very extensive or deep roots or may pick up the slightest dew and survive on that).
Others have special features about their shape or structure (xeromorphs). Thick waxy cuticle (Aloe); hairy surfaces (Edelweiss); dense packing of leaves, reduced leaf size (species of cypress); reduced density of stomata (many cacti); pitted and grooved position of stomata (Ammophila) Water storage in stem and tubers, etc. (baobab). They may also protect this water store from animals by spines and chemicals.
Mechanism table[change | change source]
|Limit water loss||waxy stomata||prickly pear|
|stomata open at night||tea plant|
|CAM photosynthesis provides CO2 during day when stomata are closed||cactus|
|large hairs on surface||bromeliads|
|curled leaves||esparto grass|
|Storage of water||succulent leaves||Kalanchoe|
|succulent Plant stem||Euphorbia|
|Water uptake||deep root system||Acacia, Prosopis|
|below water table||Nerium oleander|
|absorbing surface moisture from leaf hairs or trichomes||Tillandsia|
References[change | change source]
- Taylor D.J; N.P.O. Green & G.W. Stout 2001. Biological Science 1 & 2, 3rd edition. Cambridge University Press. ISBN 0-521-56178-7.