i) Temperature- changes in temperature affect the rate of biochemical reactions (enzymatic or metabolic) for example
photosynthesis
ii) Light (intensity, duration and wavelength)
-Plants (green) need light energy for photosynthesis
-plants need light for flowering
-some seeds like lettuce need light for germination
iii) Wind
-influences the rate of transpiration
-disperses fruits, seeds and spores for reproduction
-is an agent of pollination
iv) Humidity
-influences the rate of transpiration in plants
v) pH
-plants require specific pH to grow well (ie acidic, alkaline or neutral)
vi) Salinity
-influences the distribution of some plant species in the ecosystem eg Only those with salt tolerant tissues grow in saline areas eg Mangroves
vii) Topography
-influences the growth of plants ie plants in the leeward side have stunted growth while plants on the windward side have normal growth.
viii) Rainfall (water)
-affects the distribution of plant species in different areas.
-water is needed for seed germination; absorption of minerals;] as a raw material for photosynthesis; and as a solvent for mineral salts
-influences turgidity to bring about support in plants
-water is needed for dispersal of some seeds and fruits.
ix) Pressure (Atmospheric pressure
- influences carbon IV oxide availability which affects photosynthesis.
- affects the rate of transpiration
- influences the amount of O2/O2 concentration hence affecting respiration.
x) Mineral slats
- plants thrive best where there are enough mineral salts and in their correct proportions.
- affect the distribution of other plant species ie insectivorous plants grow in soils deficient in nitrates hence device other methods of acquiring the nutrient.
sharon kalunda answered the question on May 27, 2019 at 10:06
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