I was studying the influence of anatomy and biochemical properties of leaves on their optical properties in the Salix rosmarinifolia species. I found out that increased reflectance is apparent on the abaxial (lower) epidermis, which is caused by different leaf structure and pigment content. Concerning the leaf anatomy, I found out that palisade mesophyll share is larger than that of spongy mesophyll. However, spongy mesophyll enables better light reflection and is thus more important as far as light passing through leaves is concerned. Due to the spongy mesophyll's proximity to the abaxial epidermis as compared to the palisade mesophyll, abaxial epidermis reflects more light. It was indicated that trichome density also influences optical properties. Due to considerable trichome density, light reflection is reduced on the abaxial epidermis. However, trichomes' role is not only light reflection, as they are also of key importance for warmth preservation (NIR – infrared radiation). I did not include stomata in my research, since measurement deviations were too high.
As a key photosynthesis pigment, chlorophyll a is considered to be the most important of all chlorophyll structures, whereas other pigment roles (chlorophlyll b, carotenoids, anthocyanins and UV-absorbing substances) are primarily in protecting leaf tissue from environmental risks.
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