Ecology Lecture Notes

Xerophytes: Ecological Adaptations with PPT


ecological adaptations of xerophytes ppt

Xerophytic Adaptations of Plants
(Ecological Adaptations of Desert Plants)

What are xerophytes?

Ø  Xerophytes (xerophytic plants) are plants growing in dry habitats (xeric conditions) where the availability of water is very less.

Ø  Xeric habitat: places where water is NOT present in adequate quantity.

Ø  Xerophytes are the characteristic plants of deserts or semi-deserts areas.

Ø  Xerophytes can also grow in mesophytic conditions.

Ø  Xerophytes can tolerate:

$.  Extreme dry condition

$.  Low humidity

$.  High temperature

$.  High wind-flow

Ø  Three types of xeric habitats occurs on the earth:

(1). Physically dry habitat: the water retaining capacity of the soil very low and climate is dry (Example: a desert).

(2). Physiologically dry: water is present in excess, but not in the absorbable conditions or the plants cannot absorb it (Example: high salt water, high acidic water and high cold water, water as snow).

(3). Physically and physiologically dry: water present as mist, plants cannot absorb water from the atmosphere directly. (Example: mountain slopes)

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Ecology Lecture Notes

Characteristics of Hydrophytes with PPT (Classification and Adaptations)


Water plants adaptations PPT

Hydrophytes: Classification and Adaptations
(Morphological, Anatomical and Physiological Adaptations of Aquatic Plants)

What is an adaptation?

Ø  “Any feature of an organism which enables it to exist under conditions of its habitat is called adaptation”.

Ø  Adaptations are for withstanding adverse conditions of environment and to utilize the maximum benefit of the environment (nutrition or conditions).

Ø  Adaptations in plants may be in:

1.   Morphological features

2.   Anatomical features

3.   Physiological characters

4.   Reproductive characters

Classification of plants based on water relation (Warming, 1990)

(1). Hydrophytes: plants growing in or near water.

(2). Xerophytes: plants adapted to survive under very poor availability of water.

(3). Mesophytes: plants growing in an environment which is neither very dry nor very wet.

What are hydrophytes?

Ø  Hydrophytes (aquatic plants, water plants) are plants growing in or near water.

Ø  These plants are adapted to survive in excess of water in their surroundings.

Ø  Greek: Hudor = water; Phyton = plant: water plant

Ø  Examples: Utricularia, Vallisneria, Hydrilla, Chara, Ceratophyllum, Trapa

Ø  Aquatic plants are the producers of the aquatic ecosystem.

Ø  They fix sunlight and ensures the survival of an aquatic ecosystem.

Ø  Even though plants originated in water, except algae, most of the aquatic plants are evolved from their mesophytic relatives.

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