Vplivi gospodarjenja na funkcionalne lastnosti gozdne vegetacije in ekološke razmere v dinarskih jelovo–bukovih gozdovih : doktorska disertacija

Kermavnar, Janez (author), Kutnar, Lado (mentor), Eler, Klemen (comentor)

V raziskavi smo analizirali spremembe okoljskih razmer in odzive gozdne vegetacije na različno intenziteto poseka drevja v dinarskih jelovo-bukovih gozdovih Slovenije. Eksperimentalno zasnovana študija je obsegala tri raziskovalna območja (Trnovski gozd, Snežniško območje, Kočevski Rog), kjer je bila leta 2012 na krožni površini 0,4 ha izvedena različna intenziteta poseka: kontrola (strnjeni sestoji brez poseka), 50-odstotni posek lesne zaloge sestoja (presvetlitve) in 100-odstotni posek (sestojne vrzeli). Na vsakem območju smo izbrali devet kraških vrtač, vsaka intenziteta ukrepanja pa je bila izvedena na tretjini ploskev. Popise vegetacije na večjih ploskvah (400 m2) smo izvedli pred posekom (2012), dve leti po (2014) in šest let po (2018) poseku. Na manjših ploskvicah, ki so bile razporejene na različnih delih znotraj vrtač, smo izmerili temperaturo zraka, zračno vlago in talne parametre. Ugotovili smo, da je stopnja sprememb v ekoloških dejavnikih in sestavi vegetacije sorazmerna z intenziteto poseka. Na mikroklimatske razmere je značilno vplivala interakcija med intenziteto poseka in lokalnimi topografskimi dejavniki razgibanega kraškega površja. Zastopanost funkcionalnih znakov rastlin se je med strnjenimi sestoji in vrzelmi značilno razlikovala. Po poseku se je povečal delež enoletnic/dvoletnic, trav in šašev, visokih steblik, rastlinskih vrst z lažjimi semeni, z večjo sposobnostjo razširjanja ter z daljšim obdobjem cvetenja. Naseljevanje vrzeli in presvetlitev v začetni fazi sukcesije je potekalo predvsem preko R-strategov oz. na motnje prilagojenih pionirskih vrst. Hkrati ugotavljamo, da so tipične gozdne vrste po poseku v veliki meri uspele preživeti. Sobivanje tipičnih gozdnih vrst, pomladka drevesnih vrst in kolonizatorskih rastlin z različnimi funkcionalnimi lastnostmi se je odražalo v povečani vrstni/funkcionalni pestrosti rastlinskih združb, kar lahko prispeva k ugodnemu stanju ohranjenosti gozdnega habitatnega tipa (Natura 2000). V disertaciji smo obravnavali tudi vplive naravnih in antropogenih motenj na pritalno vegetacijo v različnih gozdnih ekosistemih po Sloveniji ter analizirali pomen abiotskih in biotskih mehanizmov združevanja vrst v rastlinske združbe.

• Language: Slovenian
• Keywords: gospodarjenje z gozdom, rastlinski funkcionalni znaki, pritalna gozdna vegetacija, mikroklima sestoja, Omphalodo-Fagetum s. lat.
• Work type: Doctoral dissertation
• Typology: 2.08 - Doctoral Dissertation
• Organization: BF - Biotechnical Faculty
• Year: 2021
• PID: 20.500.12556/RUL-124521
• COBISS.SI-ID: 50582531
• Publication date in RUL: 29.01.2021

Secondary language

• Language: English
• Title: Impacts of forest management on functional properties of vegetation and ecological conditions in the dinaric fir-beech forests : doctoral dissertation

Abstract

The study analysed changes in environmental conditions and the response of forest vegetation to different management intensities in Dinaric fir-beech forests in Slovenia. The experimental design consisted of three study sites (Trnovski gozd, Snežnik, Kočevski Rog) in which tree cutting of different intensities was performed in 2012 on a circular area of 0.4 ha: control (closed stands without cutting), 50% cutting of stand growing stock (thinned stands) and 100% cutting (canopy gaps). Nine karst sinkholes were selected at each site, and each cutting intensity was implemented in one third of the plots. Vegetation surveys on larger sampling plots were conducted before cutting (2012), two years (2014) and six years (2018) after cutting. On smaller sampling plots located in different within-sinkhole positions, we measured air temperature, relative humidity and soil parameters. We found that the degree of change in ecological factors and vegetation was proportional to the intensity of cutting. Microclimatic conditions were significantly influenced by the interaction between cutting intensity and local topography associated with rugged karst terrain. Composition of plant functional traits differed significantly between control stands and canopy gaps. The proportion of annuals/biennials, grasses and sedges, tall-statured herbaceous plants, species with lighter seeds, greater dispersal ability and longer flowering duration increased after cutting. Canopy gaps and thinned stands were mainly colonized by ruderal, disturbance-adapted pioneer species. We also observed that majority of typical forest plant species were able to survive after cutting. The coexistence of typical forest species, regeneration layer of tree species and new colonists with different functional properties was manifested in the increased species/functional diversity of plant communities, which may contribute to a favourable conservation status of the forest habitat type (Natura 2000). We additionally examined the effects of natural and anthropogenic disturbances on the understory vegetation in different forest ecosystems across Slovenia and thus also analysed the relative importance of abiotic and biotic mechanisms during the process of vegetation community assembly.

• Keywords: forest management, plant functional traits, understory vegetation, stand microclimate, Omphalodo-Fagetum s. lat.