Optical properties of Salvinia auriculata leaves

Namen diplomskega dela je raziskati optične lastnosti listov plavčka (Salvinia auriculata) in ugotoviti, kateri parametri in v kakšni meri vplivajo na odbojnost in prepustnost lista za posamezne dele elektromagnetnega spektra. Proučevali smo anatomske in biokemijske lastnosti listov ter izmerili njihovo presevnost in odbojnost. Odbojnost in presevnost listov smo izmerili v območju med 280 nm in 887 nm valovne dolžine. Izračunali smo specifično listno površino in vsebnost vode. Z mikroskopom smo analizirali zgradbo lista v prečnem prerezu in izmerili razdalje med trihomi, debelino lista in posameznimi tkivi (zgornja in spodnja povrhnjica, aerenhim). V listih smo določili tudi vsebnost antocianov, klorofilov, karotenoidov in UV-absorbirajočih snovi. Rezultati meritev odbojnosti in presevnosti so pokazali najnižjo odbojnost in presevnost v UV-območju (280–400 nm) in najvišjo v območju NIR (700–887 nm). V raziskavi smo ugotovili, da na optične lastnosti vplivajo tako anatomski kot biokemijski dejavniki, ki so z odbojnimi in presevnimi spektri povezane pozitivno, nekatere pa tudi negativno. Rezultati so pokazali, da na odbojnost vplivajo le anatomske lastnosti, kot so debelina povrhnjice, debelina aerenhima in razdalja med trihomi. Na presevnost pa vplivajo anatomske in tudi biokemijske lastnosti.The purpose of the thesis was to examine optical properties of Salvinia auriculata leaves. Our goal was to find out if any of measured parameters have influence on leaf reflectance and transmittance. We studied anatomical and biochemical properties of leaves and measured transmittance and reflectance. Leaf reflectance and transmittance were measured in the range between 280 nm and 887 nm. Specific leaf area and density were determined. We analysed leaf structure with microscope and we measured the distance between trichomes and leaf tickness (upper and lower epidermis, aerenchyma). Leaf contents of anthocyanin, chlorophyll, carotenoid and UV-absorbing substances were also measured. The results of optical properties showed that chosen plant samples have very low transmittance and reflectance in the UV area (280-40 nm), while the highest transmittance and reflectance was in NIR area (700-887 nm). In this study, we found that optical properties affect both anatomical and biochemical factors, which were positively or negatively related with leaf reflectance and transmittance. The results showed that the reflectance was affected only by anatomical features such as the thickness of the epidermis, the thickness of the aerenchyma and the distance between trichomes. The transmittance wasaffected by anatomical and biochemical properties