Wind as an Ecological Factor lecture for Biology, Botany, Zoology, and Chemistry Students by Salman Saeed lecturer Botany University College of Management and Sciences Khanewal, Pakistan. About Author: Salman Saeed Qualification: M.SC (Botany), M. Phil (Biotechnology) from BZU Multan. M. Ed & B. Ed from GCU Faisalabad, Pakistan.

1. Botany department
UNIVERSITY college of management & Sciences, Khanewal,
PAKSITAN

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Salman Saeed Lecturer (Botany)

3. The wind
Factor
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Salman Saeed Lecturer (Botany)

4. WIND
 Air in motion is called wind.
 It is important factor on flat plains , along sea
coasts, at high altitude in mountains.
 It affects plants directly by increasing transpiration, by
delivering heat to relatively cool leaves, by causing
various kinds of mechanical damage, and by
scattering pollens and disprsal of seeds and fruits.
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Salman Saeed Lecturer (Botany)

5. EFFECTS OF WIND ON
PLANTS
 Carbon dioxide replenishment:
 Wind removes bound layer of still air that covers the
surface of shoot preventing the diffusion of O2 from
stomata and carbon dioxide towards stomata.
1. Cooling:
 The bounded layer accumulates heat by
conduction over epidermis .wind thins this layer,
cause cooling of leaves.
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Salman Saeed Lecturer (Botany)

6. CONT.
2. Desiccation:
 Air in motion causes evaporation rapidly thus
increasing rate of transpiration. This results in
desiccation because of removal of water from the
tissues killing the leaves and twigs.
3. Dwarfing:
 Turgidity helps the maturing cells of plant to normal
sizes. The plant develop under influence of drying
winds never attain turgidity. As result all organs are
dwarfed.
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Salman Saeed Lecturer (Botany)

7. CONT.
4. Deformation:
 When developing shoots are subjected to strong
wind pressure from a constant direction , the form
and the position of shoot may become permanently
altered. This is called deformation. Trees with
inclined trunks are observed on ridges.
5. Lodging:
 It is a form of injury caused by violent wind in which
crop plants flattened against the ground.
 But if stem is not mature ,plant become partially
erect once.
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Salman Saeed Lecturer (Botany)

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Salman Saeed Lecturer (Botany)

9. 6. Breakage:
 Wind promote breakage in plants.
 Trees with soft and brittle wood are more
susceptible to breakage. High wind uproot the
trees.
 Single or group of trees which are uprooted in a
forest are termed as wind falls or wind throws.
CONT.
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Salman Saeed Lecturer (Botany)

10. 7. Abrasion:
 Wind carrying particles of ice or soil is very
potent abrasive force. Bark and buds may be
eroded away .Crops grown on sandy soil are
often damaged in this way.
8. Wind pollination (Anemophily):
 In cool and cold climates the vast majority of
trees , shrubs and herbs are wind pollinated.
CONT.
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Salman Saeed Lecturer (Botany)

11. 9. wind dispersal (Anemochory):
 Wind is efficient dispersal agent and most
jterrestrial plant depend on it to scatter their
disseminules ( seeds and fruits). The fruits and
seeds have developed certain adaptations for
wind dispersal such as smaller size and reduced
weight , production of wings and hairs so that they
carry by wind easily.
CONT.
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Salman Saeed Lecturer (Botany)

12.  Seeds and fruits of certain plants have developed
specialized ‘mechanism such as tumbling, catapult
mechanism etc’ are dispersed by wind.
CONT.
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Salman Saeed Lecturer (Botany)

13. ANEMOMETER
 Wind is measured by anemometer.
 Robinson anemometer.
 It consist of three or four arms –arms fixed to
vertical shaft operates gears motivating a dial.
 Average velocities can be taken .
 This provide a much more useful index of velocities.
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Salman Saeed Lecturer (Botany)

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Salman Saeed Lecturer (Botany)

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Salman Saeed Lecturer (Botany)
Salmanbotanist@gmail.com