Xerophyte

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A xerophyte species Euphorbia virosa

Xerophytes are plants which are adapted to dry/desert areas. To survive these harsh conditions they have special features.[1] For example, a cactus has white hairs which help to prevent water loss. Another example are Manzanita plants, which have a thick waxy coating and keep their leaves vertical to the sun.

Adaptions[change | edit 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 (Cupressus); reduced density of stomata (Cactus); 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 | edit source]

Mechanism Adaptation Example
Limit water loss waxy stomata prickly pear
few stomata
sunken stomata pine
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
fleshy tuber Raphionacme
Water uptake deep root system Acacia, Prosopis
below water table Nerium oleander
absorbing surface moisture from leaf hairs or trichomes Tillandsia


References[change | edit source]

  1. 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.