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Iskalni niz: "vrsta gradiva" (1) AND "polno besedilo" AND "organizacija" (Gozdarski inštitut Slovenije) .

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1.
Climatic regulation of leaf and cambial phenology in Quercus pubescens : their interlinkage and impact on xylem and phloem conduits
Jožica Gričar, Jernej Jevšenak, Polona Hafner, Peter Prislan, Mitja Ferlan, Martina Lavrič, Dominik Vodnik, Klemen Eler, 2022

Povzetek: Increased frequency and severity of stressful events affects the growth patterns and functioning of trees which adjust their phenology to given conditions. Here, we analysed environmental effects (temperature, precipitation, VPD and SWC) on the timing of leaf phenology, seasonal stem radial growth patterns, and xylem and phloem anatomy of Quercus pubescens in the sub-Mediterranean in the period 2014%2019, when various adverse weather events occurred, i.e. spring drought in 2015, summer fire in 2016 and summer drought in 2017. Results showed that the timings of leaf and cambium phenology do not occur simultaneously in Q. pubescens, reflecting different environmental and internal constraints. Although year-to-year variability in the timings of leaf and cambial phenology exists, their chronological sequence is fairly fixed. Different effects of weather conditions on different stages of leaf development in spring were observed. Common climatic drivers (i.e., negative effect of hot and dry summers and a positive effect of increasing moisture availability in winter and summer) were found to affect the widths of xylem and phloem increments with more pronounced effect on late formed parts. A legacy effect of the timing of leaf and cambial phenology of the previous growing season on the timing of phenology of the following spring was confirmed. Rarely available phloem data permitted a comprehensive insight into the interlinkage of the timing of cambium and leaf phenology and adjustment strategies of vascular tissues in Mediterranean pubescent oak to various environmental constraints, including frequent extreme events (drought, fire). Our results suggest that predicted changes in autumn/winter and spring climatic conditions for this area could affect the timings of leaf and stem cambial phenology of Q. pubescens in the coming years, which would affect stem xylem and phloem structure and hydraulic properties, and ultimately its performance.
Ključne besede: pubescent oak, leaf development, radial growth, initial earlywood vessel, sieve tube, anatomy, cambial cell production, extreme weather events
DiRROS - Objavljeno: 06.09.2021; Ogledov: 48; Prenosov: 8
.pdf Celotno besedilo (7,00 MB)

2.
Empirical approach for modelling tree phenology in mixed forests using remote sensing
Koffi Dodji Noumonvi, Gal Oblišar, Ana Žust, Urša Vilhar, 2021

Povzetek: : Phenological events are good indicators of the effects of climate change, since phenological phases are sensitive to changes in environmental conditions. Although several national phenological networks monitor the phenology of different plant species, direct observations can only be conducted on individual trees, which cannot be easily extended over large and continuous areas. Remote sensing has often been applied to model phenology for large areas, focusing mostly on pure forests in which it is relatively easier to match vegetation indices with ground observations. In mixed forests, phenology modelling from remote sensing is often limited to land surface phenology, which consists of an overall phenology of all tree species present in a pixel. The potential of remote sensing for modelling the phenology of individual tree species in mixed forests remains underexplored. In this study, we applied the seasonal midpoint (SM) method with MODIS GPP to model the start of season (SOS) and the end of season (EOS) of six different tree species in Slovenian mixed forests. First, substitute locations were identified for each combination of observation station and plant species based on similar environmental conditions (aspect, slope, and altitude) and tree species of interest, and used to retrieve the remote sensing information used in the SM method after fitting the best of a Gaussian and two double logistic functions to each year of GPP time series. Then, the best thresholds were identified for SOS and EOS, and the results were validated using cross-validation. The results show clearly that the usual threshold of 0.5 is not best in most cases, especially for estimating the EOS. Despite the difficulty in modelling the phenology of different tree species in a mixed forest using remote sensing, it was possible to estimate SOS and EOS with moderate errors as low as <8 days (Fagus sylvatica and Tilia sp.) and <10 days (Fagus sylvatica and Populus tremula), respectively.
Ključne besede: phenology modelling, start of season, end of season, remote sensing, MODIS GPP, vegetation indices, threshold methods
DiRROS - Objavljeno: 23.08.2021; Ogledov: 66; Prenosov: 40
.pdf Celotno besedilo (2,63 MB)

3.
Aktiviranje gospodarjenja v zasebnih gozdovih s poslovnim sodelovanjem med zasebnimi lastniki gozdov in ponudniki gozdarskih storitev: študij primera revir Vodice
Nina Iveta, Špela Pezdevšek Malovrh, 2021

Povzetek: V prispevku smo preverjali možnost aktiviranja gospodarjenja v zasebnih gozdovih s pomočjo poslovnega povezovanja znotraj poslovnih modelov 'zakup gozda' in 'upravljanje gozda' med zasebnimi lastniki gozdov in ponudniki gozdarskih storitev. S pomočjo anketiranja zasebnih lastnikov gozda (n = 205) in ponudnikov gozdarskih storitev (n = 14) smo ugotovili, da je pripra%vljenost za poslovno sodelovanje v obeh predlaganih poslovnih modelih večja pri ponudnikih gozdarskih storitev, kot pa je pri zasebnih lastnikih gozdov. Nadalje smo ugotovili, da je poslovno sodelovanje znotraj predlaganih poslovnih modelov uresni%čljivo, saj je stopnja sodelovanja zasebnih lastnikov gozdov s ponudniki gozdarskih storitev v 10-letnem obdobju zadovoljiva, hkrati pa so se predlagani pogoji, ki urejajo poslovno razmerje in temeljne obveznosti pogodbenih strank, izkazali za primerne za oba poslovna partnerja. Za začetek vzpostavitve poslovnega sodelovanja je treba najprej poskrbeti za promocijo poslovnega povezovanja in sodelovanja na lokalnem nivoju ter vzpostaviti poslovne odnose med potencialnimi partnerji.
Ključne besede: zasebni gozdovi, gospodarjenje, poslovno sodelovanje zasebnih lastnikov gozdov, ponudniki gozdarskih storitev, poslovni modeli, zakup gozda, upravljanje gozda, zasebni lastniki gozdov
DiRROS - Objavljeno: 17.08.2021; Ogledov: 146; Prenosov: 80
.pdf Celotno besedilo (821,00 KB)

4.
Značilnosti opravljanja sečnje in spravila v zasebnih gozdovih v Sloveniji
Matevž Triplat, Nike Krajnc, Darja Stare, Špela Ščap, 2021

Povzetek: V raziskavi, opravljeni leta 2019, je bilo zajetih 544 naključno izbranih gospodinjstev, ki imajo v lasti gozd. Več kot polovica anketi%ranih ima v lasti gozdno posest, veliko od 1 do 4,99 ha. Za 62 % anketiranih je glavni namen gospodarjenja z gozdom uporaba lesa za lastne potrebe. V obdobju 2015%2019 je sečnjo in spravilo opravljalo 71 % anketiranih, ki so v tem času skupaj posekali nekaj manj kot 50.000 m3 lesa (24 m3 /ha ali 141 m3 na gospodinjstvo). Intenziteta sečnje je bila najvišja pri zasebnih lastnikih z malimi gozdnimi posestmi (do 0,99 ha), in sicer v povprečju 41,4 m3 /ha. Analiza je pokazala, da obstajajo statistično značilne razlike med velikostjo gozdne posesti in intenziteto sečnje. V anketi je bilo ugotovljeno, da so za 41 % sečnje in spravila poskrbeli poklicni izvajalci del. Z raziskavo smo potrdili značilen vpliv velikosti zasebne gozdne posesti na način izvedbe sečnje in spravila. Rezultati so pokazali, da je največji delež zasebnih lastnikov, ki vsa dela opravijo s pomočjo najetih izvajalcev, v velikostnem razredu gozdne posesti od 5 do 9,99 ha. Z raziskavo nismo potrdili statistično značilnih razlik v intenziteti sečnje med spoloma zasebnih lastnikov gozdov
Ključne besede: zasebni lastniki, anketa, intenziteta sečnje, struktura lastnikov, gozdna posest, sečnja, spravilo, zasebni gozdovi
DiRROS - Objavljeno: 17.08.2021; Ogledov: 131; Prenosov: 69
.pdf Celotno besedilo (953,03 KB)

5.
The influence of land use on the spatial distribution and intensity of heat islands in Slovenia
Anica Simčič, Petra Pečan, Mojca Nastran, Milan Kobal, 2021

Povzetek: Heat islands (HI) are a common anthropogenic phenomenon and are defined as artificial surfaces (urban areas) that have a higher average temperature than their surroundings (rural areas). The aim of this work was to determine the influence of land use on the spatial distribution and intensity (HIi ) of HI in Slovenia. The MODIS Land Surface Temperature (LST) and Corine Land Cover (CLC) databases were used to perform the analysis. Within the identified HI, two HI levels were determined based on temperature difference. The results revealed a statistically significant negative correlation between HIi and both forest co%ver and forest fragmentation (forest edge density and ratio of mean forest patch size to HI size). Artificial surface was positively correlated with HIi . The results contribute to the understanding of the spatial distribution of HI and HIi and provide informati%on for spatial planning and policy-making to reduce the negative impact of HI.
Ključne besede: heat island, forest cover, artificial surface, forest fragmentation
DiRROS - Objavljeno: 17.08.2021; Ogledov: 251; Prenosov: 100
.pdf Celotno besedilo (1011,73 KB)

6.
Modeliranje višinske in debelinske rasti dominantnih dreves ter ocenjevanje indeksov produkcijske sposobnosti gozdnih rastišč
Andrej Bončina, Vasilije Trifković, Živa Bončina, 2021

Povzetek: Modeli višinskega in debelinskega priraščanja dreves so pomembni za upravljanje gozdov, saj so podlaga za določanje režima redčenj, ciljnih premerov drevesnih vrst in optimalnega razmerja razvojnih faz ter ocenjevanje produkcijske sposobnosti goz%dnih rastišč. S podatki s stalnih vzorčnih ploskev smo za dva gozdna tipa (gradnovo bukovje na izpranih tleh in predalpsko jelovo bukovje) modelirali višinsko rast dominantnih bukev in smrek glede na njihov premer. Za obe vrsti smo ocenili rastiščni produkcijski indeks (SPI), ki je dominanta višina drevja pri prsnem premeru 45 cm. Na podlagi debelinskega priraščanja do%minantnih dreves smo ocenili prehodne dobe in povprečno starost dreves glede na njihovo debelino. To so bili vhodni podatki za določitev regresijskega modela višine dominantnih dreves glede na njihovo starost. SPI je za smreko v primerjavi z bukvijo pričakovano višji, pri bukvi je vrednost SPI višja na rastišču gradnovega bukovja na izpranih tleh (28,7 m proti 27,9 m), pri smreki pa na rastišču predalpskega jelovega bukovja (31,3 m proti 29,7 m). Vrednosti rastiščnih indeksov (SI; dominantna višina drevja pri starosti 100 let) smreke na rastiščih gradnovega bukovja in predalpskega jelovega bukovja so 33,4 in 32,0, bukve pa 29,0 in 27,0. Z opisanim postopkom smo za izbrana gozdna rastiščna tipa določili indekse produkcijske sposobnosti gozdnih smreke in bukve (SI in SPI); uporabnost postopka je treba preveriti še za druge drevesne vrste in gozdne rastiščne tipe.
Ključne besede: dominantna drevesa, višinska rast, debelinska rast, rastiščni indeks, rastiščni produkcijski indeks, Fagus sylvatica, Picea abies
DiRROS - Objavljeno: 17.08.2021; Ogledov: 201; Prenosov: 95
.pdf Celotno besedilo (840,99 KB)

7.
Vpliv podnebnih sprememb na dinamiko glivnega razkroja lesa v Sloveniji
Miha Humar, Boštjan Lesar, Davor Kržišnik, 2021

Povzetek: Intenziteta glivnega razkroja je v največji meri odvisna od vrste lesa, temperature in padavinskih dogodkov. Če želimo oceniti življenjsko dobo in intervale vzdrževanja lesenih objektov, moramo oceniti, kako se bo v določenem okolju les obnašal. V ta namen so nam na voljo raznoliki modeli. V praksi se največ uporablja pristop, ki ga je razvil Theodore Scheffer. Scheffer je predlagal klimatski indeks (Schefferjev klimatski indeks - SCI), ki temelji na številu padavinskih dni in povprečni mesečni temperaturi. Na podlagi teh klimatskih podatkov smo izračunali Schefferjev klimatski indeks za izbrane lokacije v Sloveniji. Rezultati analize klimatskih razmer kažejo, da je Schefferjev klimatski indeks v večini analiziranih krajev v Sloveniji višji, kot je bil pred desetletji. Intenziteta razkroja se je povečala v vseh analiziranih krajih z izjemo Portoroža. Največje zvišanje Schefferjevega klimatskega indeksa smo zaznali v Ratečah.
Ključne besede: les, Schefferjev klimatski indeks, razkroj, podnebne spremembe, temperatura, padavinski dogodki
DiRROS - Objavljeno: 17.08.2021; Ogledov: 118; Prenosov: 65
.pdf Celotno besedilo (1004,81 KB)

8.
9.
Global homogenization of the structure and function in the soil microbiome of urban greenspaces
Manuel Delgado-Baquerizo, David J. Eldridge, Yu-Rong Liu, Blessing Sokoya, Jun-Tao Wang, Hang-Wei Hu, Ji-Zheng He, Felipe Bastida, José L. Moreno, Adebola R. Bamigboye, Tine Grebenc, Tina Unuk, 2021

Povzetek: The structure and function of the soil microbiome of urban greenspaces remain largely undetermined. We conducted a global field survey in urban greenspaces and neighboring natural ecosystems across 56 cities from six continents, and found that urban soils are important hotspots for soil bacterial, protist and functional gene diversity, but support highly homogenized microbial communities worldwide. Urban greenspaces had a greater proportion of fast-growing bacteria, algae, amoebae, and fungal pathogens, but a lower proportion of ectomycorrhizal fungi than natural ecosystems. These urban ecosystems also showed higher proportions of genes associated with human pathogens, greenhouse gas emissions, faster nutrient cycling, and more intense abiotic stress than natural environments. City affluence, management practices, and climate were fundamental drivers of urban soil communities. Our work paves the way toward a more comprehensive global-scale perspective on urban greenspaces, which is integral to managing the health of these ecosystems and the well-being of human populations.
Ključne besede: soil biodiversity, structural diversity, functional diversity, urban soils
DiRROS - Objavljeno: 15.07.2021; Ogledov: 122; Prenosov: 85
.pdf Celotno besedilo (4,34 MB)

10.
Contrasting resource dynamics in mast years for European Beech and Oak - a continental scale analysis
Anita Nussbaumer, Arthur Gessler, Sue Benham, B. De Cinti, Sophia Etzold, Morten Ingerslev, Frank Jacob, François Lebourgeois, Tom Levanič, Hrvoje Marjanović, 2021

Povzetek: Resource allocation to different plant tissues is likely to be affected by high investment into fruit production during mast years. However, there is a large knowledge gap concerning species-specific differences in resource dynamics. We investigated the influence of mast years on stem growth, leaf production, and leaf carbon (C), nitrogen (N), and phosphorus (P) concentrations and contents in Fagus sylvatica, Quercus petraea, and Q. robur at continental and climate region scales using long-term data from the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) and similar datasets. We discussed the results in the light of opposing resource dynamics hypotheses: (i) resource accumulation before mast years and exhaustion after mast years (resource storage hypothesis), (ii) shifting resources from vegetative to generative compartments (resource switching hypothesis), and (iii) investing resources concurrently in both vegetative and generative compartments (resource matching hypothesis). Linear mixed-effects modelling (LMM) showed that both stem growth and leaf production were negatively influenced by weather conditions which simultaneously lead to high fruit production. Thus, the impact of generative on vegetative growth is intermixed with effects of environmental factors. Superposed epoch analyses and LMM showed that for mast behaviour in F. sylvatica, there are indicators supporting the resource storage and the resource switching hypotheses. Before mast years, resources were accumulated, while during mast years resources switched from vegetative to generative tissues with reduced stem and leaf growth. For the Quercus species, stem growth was reduced after mast years, which supports the resource storage hypothesis. LMM showed that leaf C concentrations did not change with increasing fruit production in neither species. Leaf N and P concentrations increased in F. sylvatica, but not in Quercus species. Leaf N and P contents decreased with increasing fruit production in all species, as did leaf C content in F. sylvatica. Overall, our findings suggest different resource dynamics strategies in F. sylvatica and Quercus species, which might lead to differences in their adaptive capacity to a changing climate.
Ključne besede: climate change, Fagus sylvatica, long-term monitoring, mast fruiting, Quercus petraea, Quercus robur, resource dynamics
DiRROS - Objavljeno: 15.07.2021; Ogledov: 96; Prenosov: 55
.pdf Celotno besedilo (7,63 MB)

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