Optical properties of bark in selected shrub species

V magistrski nalogi smo preučevali fiziološke, morfološke in biokemijske lastnosti skorje pri štirih grmovnih vrstah: navadni leski (Corylus avellana), črnem bezegu (Sambucus nigra), navadni kalini (Ligustrum vulgare) in navadnem šipku (Rosa canina). V območju valovnih dolžin med 280 nm in 885 nm smo merili odbojnost in presevnost skorje. Preučevali smo fotokemično učinkovitost FS II, določili vrednost klorofila a in b, karotenoidov, antocianov ter UV-B in UV-A absorbirajočih snovi v skorji. Analizirali smo anatomske in morfološke lastnosti skorje, tako da smo opravili prečne prereze stebla pri vseh grmovnih vrstah. Debelina periderma naj bi vplivala na optične lastnosti skorje, vendar sta presevnost in odbojnost odvisni od števila živih oziroma mrtvih celic v felemu (pluti). Vsebnost posameznih pigmentov je odvisna od svetlobnih razmer in značilnosti vrste. Vrste v odbojnosti dosežejo vrh v zelenem delu spektra, presevnost pa v rumenem delu spektra. Analiza povezanosti optičnih lastnosti z morfološkimi ter biokemijskimi lastnostmi je pokazala večji pomen morfologije zunanje plasti stebla v primerjavi z biokemijskimi lastnostmi.In the master’s thesis, we have studied optical properties and physiological, morphological and biochemical characteristics of the bark in four shrub species: common hazel (Corylus avellana), black elder (Sambucus nigra), common privet (Ligustrum vulgare) and dog rose (Rosa canina). In the wavelength range between 280 nm and 885 nm, we measured the reflectivity and transmittance of the crust. We studied the photochemical effectiveness of FS II and determined the amounts of the chlorophylls a and b, carotenoids, anthocyanins and UV-B and UV-A absorbing substances in the bark. We analysed anatomic and morphological characteristics of the bark using a cross-sections of the stem. The thickness of the periderm should exert an impact on optical characteristics of the bark, but light transmittance and reflectance depend on the number of living or dead cells in the phellem (cork). The content of individual pigments depends on light conditions, which differed among species. The light transmittance reach their maximum in the green range (579 nm) and reflectance reach their maximum in the yellow range (600 nm). The analysis of the correlation of optical properties with morphological and biochemical properties has shown more importance in the morphology of the outer layers of the stem compared to biochemical properties