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Abstract: V letu 2023 − eno leto po obsežnem požaru na Goriškem Krasu, ki je divjal julija leta 2022 − smo na izbranih gozdnih vzorčnih ploskvah popisali zeliščno, grmovno in drevesno vegetacijo in analizirali tla do globine 10 cm. Ploskve smo izbrali na lokacijah stalnih vzorčnih ploskev ZGS z različno stopnjo poškodovan osti zaradi požara. Na izbranih ploskvah smo skupno popisali 260 vrst praprotnic in semenk. V drevesni plasti smo popisali trinajst vrst (enajst domorodnih in dve tujerodni), v grmovni plasti trideset, v zeliščni pa 255. V drevesni plasti so bili najpogostejši mali jesen, črni gaber in črni bor, v grmovni mali jesen, navadni ruj in robide. V zeliščni plasti smo med drugimi popisali tudi devetnajst drevesnih vrst, ki so pomembna zasnova pri naravni obnovi požganega gozda na Krasu; najpogostejša sta bila črni gaber in rešeljika. Gradient poškodovanosti po požaru se jasno kaže v večini vegetacijskih in talnih spremenljivk. Statistično značilne razlike med skupinami ploskev z različno stopnjo poškodovanosti smo ugotovili za šest parametrov: pH-vrednosti in vsebnosti žvepla v organskem delu tal, zastiranje drevesne plasti, zastiranje mahov, število vrst v spodnji drevesni plasti, število vrst zeliščne plasti. Na ploskvah smo prepoznali devet (ter še tri vrste na požarišču zunaj ploskev) invazivnih ali potencialno invazivnih tujerodnih rastlinskih vrst; med drevesnimi sta bila najpogostejša robinija in visoki pajesen. Študija pomembno prispeva k razumevanju razvoja vegetacije, pomlajevanja ključnih drevesnih vrst in poškodb gozdnih tal v inicialni fazi po obsežnem požaru.
Keywords: gozdna vegetacija, poškodbe tal, gozdni požar, drevesne vrste, pestrost vrst, invazivne rastlinske vrste, Kras, Slovenija
Published in DiRROS: 21.05.2024; Views: 100; Downloads: 59
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Abstract: Forests are important ecosystems that face threats from climate change and global environmental shifts, with invasive alien plant species being a significant concern. Some of these invasive species have already become established, while others are in the process of naturalisation. Although forests are a relatively stable ecosystem, extreme weather events increase their vulnerability to change, and clearings left after natural disturbances are particularly susceptible to invasion by alien plant species (IAPS). We created risk maps of two species that have spread rapidly in the last decade: American pokeweed (Phytolacca americana) and the tree of heaven (Ailanthus altissima). We prepared a generalised linear model based on the occurrence data collected within the LIFE ARTEMIS project. Eleven environmental variables were used to determine habitat characteristics. We constructed two models for each species: one covering the entirety of Slovenia and the other specifically for the forested areas in Slovenia, with the latter incorporating forest-specific variables (such as forest sanitation felling and monocultures). We observed the presence of both species at lower altitudes and in close proximity to water sources. American pokeweed tends to occur nearer to railways, while the presence of the tree of heaven is associated with areas lacking carbonate parent material and influenced by land use patterns. In forested areas, the occurrence of American pokeweed is influenced by forest habitat characteristics, such as disturbances caused by extreme weather events or the prevalence of Norway spruce monocultures. In contrast, the occurrence of the tree of heaven is influenced by more general environmental variables, such as altitude and proximity to railways. Consequently, we have generated risk maps for the entirety of Slovenia and separately for forested areas, both of which indicate similar levels of risk, particularly for the tree of heaven. The risk map for American pokeweed highlights numerous vulnerable areas, especially forest edges, which are highly susceptible to invasion. Furthermore, there is a higher likelihood of this species occurring in areas that have undergone sanitation felling. This study suggests that the production of risk maps of IAPS could be improved by focussing on habitat types and taking into account habitat-specific variables. This approach could enhance the early detection and management of these invasive species.
Keywords: American pokeweed, tree of heaven, species distribution modelling, forests, forest disturbance, habitat suitability
Published in DiRROS: 26.03.2024; Views: 208; Downloads: 1687
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Keywords: vrednotenje, vplivi, državni prostorski načrt, vetrna elektrarna, gozdovi, gozdarstvo, Paški Kozjak
Published in DiRROS: 03.01.2024; Views: 290; Downloads: 0

Abstract: Introduction: Herbaceous plant species constitute an essential element of the flora of European beech (Fagus sylvatica) forests. There is increasing evidence that rapidly changing climate is likely to modify the spatial distribution of plant species. However, we lack understanding of the impact that climate change might have on beech forest herbs across the European continent. We investigated the possible effects of predicted increasing rates of global warming and altered precipitation regimes on 71 forest herbs closely associated with beech forests, but with varying biogeographic and climatic niche attributes. Methods: By using a total of 394,502 occurrence records and an ensemble of species distribution models (SDMs), we quantified the potential current distribution and future (2061-2080) range shifts in climatic suitability (expressed as occurrence probability, OP) according to two climate change scenarios (moderate SSP2-4.5 and severe SSP5-8.5). Results: Overall, precipitation of the warmest quarter and temperature seasonality were the most influential predictors in shaping current distribution patterns. For SSP5-8.5 scenario, all studied species experienced significant reductions (52.9% on average) in the total size of highly suitable areas (OP >0.75). However, the magnitude and directions of changes in the climatic suitability were highly species-specific; few species might even increase OP in the future, particularly in case of SSP2-4.5 scenario. The SDMs revealed the most substantial decline of climatic suitability at the trailing edges in southern Europe. We found that climatic suitability is predicted to show unidirectional northward shift and to move toward higher elevations. The gain/loss ratio was generally higher for narrow-ranged species compared to widespread taxa. Discussion: Our findings are contextualized with regards to potential confounding factors (dispersal limitation, microclimatic buffering) that may mitigate or accelerate climate change impacts. Given the low long-distance migration ability, many beech forest herbs are unlikely to track the velocity with which macroclimatic isotherms are moving toward higher latitudes, making this species group particularly vulnerable to climate change.
Keywords: species distribution modelling, global warming, range shift, climatic niche, biogeography, Europe
Published in DiRROS: 29.11.2023; Views: 328; Downloads: 164
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Keywords: vegetacija, tla, rastišče, ekologija gozda, delavnice, Javna gozdarska služba, Slovenija, fitocenologija, gozdne združbe, gozdni rastiščni tipi
Published in DiRROS: 17.08.2023; Views: 363; Downloads: 146
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