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42.
Continent-wide tree species distribution models may mislead regional management decisions : a case study in the transboundary biosphere reserve Mura-Drava-Danube
Marcus Sallmannshofer, Debojyoti Chakraborty, Harald Vacik, Gábor Illés, Markus Löw, Andreas Rechenmacher, Katharina Lapin, Sophie Ette, Dejan Stojanović, Andrej Kobler, Silvio Schueler, 2021, izvirni znanstveni članek

Povzetek: The understanding of spatial distribution patterns of native riparian tree species in Europe lacks accurate species distribution models (SDMs), since riparian forest habitats have a limited spatial extent and are strongly related to the associated watercourses, which needs to be represented in the environmental predictors. However, SDMs are urgently needed for adapting forest management to climate change, as well as for conservation and restoration of riparian forest ecosystems. For such an operative use, standard large-scale bioclimatic models alone are too coarse and frequently exclude relevant predictors. In this study, we compare a bioclimatic continent-wide model and a regional model based on climate, soil, and river data for central to south-eastern Europe, targeting seven riparian foundation species%Alnus glutinosa, Fraxinus angustifolia, F. excelsior, Populus nigra, Quercus robur, Ulmus laevis, and U. minor. The results emphasize the high importance of precise occurrence data and environmental predictors. Soil predictors were more important than bioclimatic variables, and river variables were partly of the same importance. In both models, five of the seven species were found to decrease in terms of future occurrence probability within the study area, whereas the results for two species were ambiguous. Nevertheless, both models predicted a dangerous loss of occurrence probability for economically and ecologically important tree species, likely leading to significant effects on forest composition and structure, as well as on provided ecosystem services.
Ključne besede: bioclimatic model, ecological niche model, forest management, tree species selection, riparian forest habitat, climate change adaptation
Objavljeno v DiRROS: 22.03.2021; Ogledov: 1227; Prenosov: 831
.pdf Celotno besedilo (2,47 MB)
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43.
Preverjanje uporabnosti modela SiWaWa za simuliranje razvoja čistih bukovih in smrekovih enomernih sestojev v Sloveniji
Matija Klopčič, 2021, izvirni znanstveni članek

Povzetek: Modeli razvoja gozdov napovedujejo razvoj dreves in gozdnih sestojev glede na drevesne, sestojne, rastiščne in gozdnogospodarske dejavnike. Zaradi kompleksne narave gozdnih ekosistemov in dolgih proizvodnih ciklov je modeliranje razvoja gozdov pomemben sestavni del upravljanja gozdov. Sestojni modeli so bili prepoznani kot primerni za podporo odločanju pri upravljanju z gozdovi. Primer takega modela je švicarski model SiWaWa, ki smo ga preizkusili v pričujoči raziskavi. Na štirih vzorcih po 50 stalnih vzorčnih ploskev v negospodarjenih in gospodarjenih čistih bukovih in čistih smrekovih enomernih sestojih smo izvedli simulacije razvoja gozdov za obdobje 10 let, nato pa smo primerjali dejanske vrednosti in modelske napovedi za sestojno temeljnico G, število dreves N in srednje temeljnični premer Dg. Napovedovanje razvoja čistih bukovih gozdov je bilo zadovoljivo točno; v negospodarjenih sestojih je celotna napaka RMSE za sestojno temeljnico znašala 2,35 m2 /ha, v gospodarjenih sestojih pa 3,42 m2/ha ob upoštevanju le posekanih dreves in 4,35 m2/ha ob upoštevanju celotne mortalitete. Enako ne moremo trditi za napovedovanje razvoja čistih smrekovih sestojev. Pri slednjih so bile mere točnosti znatno slabše, saj so RMSE za napovedano sestojno temeljnico znašali 8,94 m2/ha za negospodarjene in 6,13 m2/ha ter 6,11 m2/ha za gospodarjene sestoje ob upoštevanju poseka oziroma celotne mortalitete. Model SiWaWa, ki je parametriziran za švicarske gozdove, se zdi uporaben za simuliranje razvoja čistih bukovih gozdov brez simuliranega ukrepanja (poseka) ali z njim. Zanesljive simulacije razvoja čistih smrekovih sestojev pa model zaenkrat še ne omogoča.
Ključne besede: model razvoja gozdov, gozdni sestoj, gozdna inventura, simulacije razvoja gozdov, sestojna temeljnica, število dreves, srednje temeljnični premer
Objavljeno v DiRROS: 08.03.2021; Ogledov: 1537; Prenosov: 477
.pdf Celotno besedilo (426,06 KB)

44.
Water regulation ecosystem services following gap formation in Fir-beech forests in the Dinaric Karst
Urša Vilhar, 2021, izvirni znanstveni članek

Povzetek: This paper investigates how variation in forest structural characteristics affects the water retention capacity of gaps and forests in fir-beech forests in the Dinaric Karst. Forests are identified as a key element of the landscape for provision of pristine water resources, particularly in highly vulnerable karst aquifers characterized by rapid infiltration of recharge water, high subsurface permeability, and heterogeneous underground flow. Indicators of hydrologic fluxes (drainage flux, canopy interception, transpiration, and soil evaporation) in a large experimental gap (approximately 0.2 ha in size) and those in a nearby old-growth gap were compared over a 13-year period using the Brook90 hydrological model and their structural characteristics were analyzed. In addition, the hydrologic fluxes were also simulated for a managed forest and an old-growth forest for reference. Water regulation capacity was lowest in the experimental gap, where drainage flux accounted for 81% of precipitation and the sum of canopy interception, transpiration, and soil evaporation (evapotranspiration) accounted for 18%. This was followed by the old-growth gap, where drainage flux accounted for 78% of precipitation and evapotranspiration for 23%. Water retention capacity was highest and generally similar for both forests, where 71%72% of annual precipitation drained to the subsurface. The results of this study suggest that the creation of large canopy gaps in fir-beech forests in the Dinaric Karst results in significant and long-lasting reduction in soil and vegetation water retention capacity due to unfavorable conditions for successful natural tree regeneration. For optimal provision of water regulation ecosystem services of forests in the Dinaric Karst, small, irregularly shaped canopy gaps no larger than tree height should be created, mimicking the structural characteristics of naturally occurring gaps in old-growth forests.
Ključne besede: water retention capacity, drainage flux, evapotranspiration, Brook90 hydrological model, experimental canopy gap, old-growth forest
Objavljeno v DiRROS: 05.03.2021; Ogledov: 960; Prenosov: 806
.pdf Celotno besedilo (1,38 MB)
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45.
Spletna orodja za upravljanje s smrekovimi podlubniki : Web tools for management of Spruce Bark Beetles
Nikica Ogris, 2020, strokovni članek

Povzetek: V prispevku predstavljamo spletna orodja, s katerimi si lahko pomagamo pri upravljanju s smrekovimi podlubniki. Na voljo je več spletnih orodij, ki pomagajo pri načrtovanju spremljanja kontrolnih pasti in kontrolnih nastav, ki jih uporabljamo za ugotavljanje gostote populacij smrekovih podlubnikov. Na podlagi teh podatkov vsako leto ugotavljamo lokacije pasti, kjer so se podlubniki prenamnožili. Posledično moramo na takšnih lokacijah povečati obseg ukrepov in pospešiti izvajanje varstva gozdov pred podlubniki zaradi preprečevanja škode v gozdovih. Rezultate teh analiz objavljamo v spletni reviji Napovedi o zdravju gozdov. V okviru Javne gozdarske službe na Gozdarskem inštitutu Slovenije, tj. Poročevalsko prognostično-diagnostične službe za gozdove, vsako leto izdelamo kratkoročno napoved sanitarnega poseka smreke. Napoved je verjetnostna in pomaga pri bolj osredotočenem iskanju žarišč smrekovih lubadark; najprej iščemo žarišča na lokacijah, kjer je največja verjetnost pojava žarišč. Tako se poveča verjetnost, da žarišča najdemo še v zgodnji fazi napada, kar omogoči več časa za ukrepanje. Ko enkrat najdemo žarišče, nas zanima, koliko časa imamo za sanacijo. Za ta namen smo razvili spletno orodje, ki izračuna priporočeni rok za izvedbo ukrepov za zatiranje smrekovih podlubnikov. S tem orodjem si lahko postavimo prioritete za sanacijo žarišč lubadark, tj. najprej saniramo žarišča, katerim bo rok za izvedbo ukrepov potekel najprej. Izdelali smo tudi dolgoročno napoved sanitarne sečnje zaradi žuželk, ki je lahko v pomoč pri določitvi smernic za dolgoročno gospodarjenje s smreko in pri usmerjanju ciljne drevesne sestave v gozdnogospodarskih načrtih. Vsa navedena spletna orodja je razvil Gozdarski inštitut Slovenije in so javno dostopna na spletnem portalu Varstvo gozdov (www.zdravgozd.si).
Ključne besede: rok sanitarne sečnje, fenološki model, RITY, CHAPY, osmerozobi smrekov lubadar, Ips typographus, šesterozobi smrekov lubadar, Pityogenes chalcographus, pripomoček, spremljanje, monitoring, namnožitev, napoved, prognoza, gostota populacije
Objavljeno v DiRROS: 14.11.2020; Ogledov: 1586; Prenosov: 469
.pdf Celotno besedilo (2,19 MB)

46.
Growth-limiting factors and climate response variability in Norway spruce (Picea abies L.) along an elevation and precipitation gradients in Slovenia
Jernej Jevšenak, Ivan Tychkov, Jožica Gričar, Tom Levanič, Jan Tumajer, Peter Prislan, Domen Arnič, Margarita Popkova, Vladimir V. Shishov, 2020, izvirni znanstveni članek

Povzetek: Norway spruce (Picea abies L.) is among the most sensitive coniferous species to ongoing climate change. However, previous studies on its growth response to increasing temperatures have yielded contrasting results (from stimulation to suppression), suggesting highly site-specific responses. Here, we present the first study that applies two independent approaches, i.e. the nonlinear, process-based Vaganov-Shashkin (VS) model and linear daily response functions. Data were collected at twelve sites in Slovenia differing in climate regimes and ranging elevation between 170 and 1300 m a.s.l. VS model results revealed that drier Norway spruce sites at lower elevations are mostly moisture limited, while moist high-elevation sites are generally more temperature limited. Daily response functions match well the pattern of growth-limiting factors from the VS model and further explain the effect of climate on radial growth: prevailing growth-limiting factors correspond to the climate variable with higher correlations. Radial growth correlates negatively with rising summer temperature and positively with higher spring precipitation. The opposite response was observed for the wettest site at the highest elevation, which positively reacts to increased summer temperature and will most likely benefit from a warming climate. For all other sites, the future radial growth of Norway spruce largely depends on the balance between spring precipitation and summer temperature.
Ključne besede: Vaganov-Shashkin model, climate-growth correlations, tree rings, process-based modelling, dendroTools, dendroclimatology
Objavljeno v DiRROS: 21.10.2020; Ogledov: 1210; Prenosov: 950
.pdf Celotno besedilo (1,94 MB)
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47.
Meteorološki kazalnik požarne ogroženosti gozdov v Sloveniji
Tomaž Šturm, Nikica Ogris, 2020, samostojni znanstveni sestavek ali poglavje v monografski publikaciji

Ključne besede: požarna ogroženost gozdov, požarna nevarnost, vreme, model, CFFWIS, FWI, ALADIN, INCA, Slovenija
Objavljeno v DiRROS: 24.09.2020; Ogledov: 1232; Prenosov: 816
.pdf Celotno besedilo (7,70 MB)
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48.
KEYLINK : towards a more integrative soil representation for inclusion in ecosystem scale models : I. : review and model concept
Gabrielle I. Deckmyn, Omar Flores, Mathias Mayer, Xavier Domene, Andrea Schnepf, Katrin Kuka, Kris van Looy, Daniel P. Rasse, Maria J.I. Briones, Sébastien Barot, Matty Berg, E. I. Vanguelova, Ivika Ostonen, Harry Vereecken, Laura Martinez Suz, Beat Frey, Aline Frossard, Alexei Tiunov, Jan Frouz, Tine Grebenc, Maarja Öpik, Mathieu Javaux, Alexei Uvarov, Olga Vindušková, Paul Henning Krogh, Oskar Franklin, Juan Jiménez, Jorge Curiel Yuste, 2020, izvirni znanstveni članek

Povzetek: The relatively poor simulation of the below-ground processes is a severe drawback for many ecosystem models, especially when predicting responses to climate change and management. For a meaningful estimation of ecosystem production and the cycling of water, energy, nutrients and carbon, the integration of soil processes and the exchanges at the surface is crucial. It is increasingly recognized that soil biota play an important role in soil organic carbon and nutrient cycling, shaping soil structure and hydrological properties through their activity, and in water and nutrient uptake by plants through mycorrhizal processes. In this article, we review the main soil biological actors (microbiota, fauna and roots) and their effects on soil functioning. We review to what extent they have been included in soil models and propose which of them could be included in ecosystem models. We show that the model representation of the soil food web, the impact of soil ecosystem engineers on soil structure and the related effects on hydrology and soil organic matter (SOM) stabilization are key issues in improving ecosystem-scale soil representation in models. Finally, we describe a new core model concept (KEYLINK) that integrates insights from SOM models, structural models and food web models to simulate the living soil at an ecosystem scale.
Ključne besede: soil fauna, model, Soil Organic Matter, SOM, hydrology, pore size distribution, PSD, soil biota, ecosystem
Objavljeno v DiRROS: 23.09.2020; Ogledov: 1417; Prenosov: 1189
.pdf Celotno besedilo (5,28 MB)
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