Plant functional ecology: testing selected concepts using plant species of forest site types in Slovenia

Na primeru flore slovenskih gozdov smo obravnavali štiri funkcionalne znake rastlin: specifična listna površina (SLP), vsebnost suhe snovi v listih (VSS), višina rastlin (VIŠ) in masa semen oz. spor (MAS). Prva dva znaka nakazujeta ekonomiko lista (način in učinkovitost izrabe virov), druga dva pa velikost rastlinskih organov. Preučili smo povezave med znaki rastlin in njihovimi fitoindikacijskimi vrednostmi za ekološke dejavnike svetloba (L), temperatura (T), kontinentalnost (K), vlažnost tal (F), reakcija tal (R) in hranila (N). Ugotovili smo statistično značilne korelacije: med SLP in R, N, L, F ter K med VSS in R ter N med VIŠ in N, T, R ter F med MAS in K, R, N ter T. Vzdolž prve osi ordinacijskega prostora smo prepoznali spekter listne ekonomike, ki poteka od vrst z večjimi vrednostmi SLP na produktivnejših, a hkrati senčnih rastiščih, do rastlin z večjimi vrednostmi VSS, prilagojenih na stresne ekološke razmere (npr. nizka reakcija tal ali pomanjkanje hranil oz. vode). Največji prispevek k pojasnjevanju variabilnosti v funkcionalnih lastnostih gozdnih rastlin je imel znak VIŠ, najmanjšega pa znak MAS. Ugotovitve so primerljive z dosedanjimi raziskavami, saj oba izbrana koncepta omogočata prepoznavanje pestrosti oblik in funkcij rastlin na globalni ravni. Using Slovenian forest flora as an example, we investigated four plant functional traits: specific leaf area (SLP), leaf dry matter content (VSS), plant height (VIŠ) and seed/spore mass (MAS). The first two traits define the leaf economics spectrum (way and efficiency of resource utilization), whereas the other two are linked to the size of plant organs. This study tested the correlations between plant traits and their phytoindication values for the ecological factors of light (L), temperature (T), continentality (K), soil moisture (F), soil reaction (R) and nutrients (N). We found statistically significant correlations between SLP and R, N, L, F and K between VSS and R and N between VIŠ and N, T, R and F and between MAS and K, R, N and T. Along the first axis of the ordination space, we identified a leaf economics spectrum ranging from species with higher SLP values growing on more productive but also more shaded sites to plants with higher VSS values adapted to more stressful conditions (e.g. low soil reaction or low availability of nutrients and water, respectively). The VSS trait contributed the most to explaining the variability in the functional profile of forest plants, while the MAS trait contributed the least. These findings are comparable with previous studies, as the selected concepts allow for the identification of diversity of plant form and function on a global scale.