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91.
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: 621; Prenosov: 311
.pdf Celotno besedilo (1011,73 KB)

92.
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: 605; Prenosov: 282
.pdf Celotno besedilo (840,99 KB)

93.
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: 475; Prenosov: 249
.pdf Celotno besedilo (1004,81 KB)

94.
95.
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: 307; Prenosov: 209
.pdf Celotno besedilo (4,34 MB)

96.
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: 255; Prenosov: 164
.pdf Celotno besedilo (7,63 MB)

97.
Surprising drought tolerance of Fir (Abies) species between past climatic adaptation and future projections reveals new chances for adaptive forest management
Csaba Mátyás, František Beran, Jaroslav Dostál, Jiří Čáp, Martin Fulín, Monika Vejpustková, Gregor Božič, Pál Balázs, Josef Frýdl, 2021

Povzetek: esearch Highlights: Data of advanced-age provenance tests were reanalyzed applying a new approach, to directly estimate the growth of populations at their original sites under individually generated future climates. The results revealed the high resilience potential of fir species. Background and Objectives: The growth and survival of silver fir under future climatic scenarios are insufficiently investigated at the xeric limits. The selective signature of past climate determining the current and projected growth was investigated to analyze the prospects of adaptive silviculture and assisted transfer of silver fir populations, and the introduction of non-autochthonous species. Materials and Methods: Hargreaves% climatic moisture deficit was selected to model height responses of adult populations. Climatic transfer distance was used to assess the relative drought stress of populations at the test site, relating these to the past conditions to which the populations had adapted. ClimateEU and ClimateWNA pathway RCP8.5 data served to determine individually past, current, and future moisture deficit conditions. Besides silver fir, other fir species from South Europe and the American Northwest were also tested. Results: Drought tolerance profiles explained the responses of transferred provenances and predicted their future performance and survival. Silver fir displayed significant within-species differentiation regarding drought stress response. Applying the assumed drought tolerance limit of 100 mm relative moisture deficit, most of the tested silver fir populations seem to survive their projected climate at their origin until the end of the century. Survival is likely also for transferred Balkan fir species and for grand fir populations, but not for the Mediterranean species. Conclusions: The projections are less dramatic than provided by usual inventory assessments, considering also the resilience of populations. The method fills the existing gap between experimentally determined adaptive response and the predictions needed for management decisions. It also underscores the unique potential of provenance tests.
Ključne besede: climate change, common garden, provenance test, silver fir, grand fir, Balkan firs, drought stress, resilience, climate transfer distance, adaptation
DiRROS - Objavljeno: 05.07.2021; Ogledov: 274; Prenosov: 85
.pdf Celotno besedilo (1,46 MB)

98.
Green space area and type affect bird communities in a South-eastern European city
Maarten De Groot, Katarina Flajšman, Tomaž Mihelič, Urša Vilhar, Primož Simončič, Andrej Verlič, 2021

Povzetek: Urbanization decreases the species richness and results in the homogenization of bird communities. Bird species are important indicator species for biodiversity and reflect the habitat quality of urban forests and other green spaces. In this study we investigated the key drivers that influence bird communities in urban forests and green spaces in the Southeastern European city of Ljubljana, Slovenia. We were interested in how the number of species, species dissimilarity and indicator species are affected by the type of green space (urban forest vs park), area of green space and type of urbanization (urban vs peri-urban areas). We sampled birds twice in 2012 in 39 standardized point counts across Ljubljana. We found that the abundance was influenced by the area of the green space. Species dissimilarity and species turnover are affected by the area and type of green space. Interestingly, the analysis showed that the species composition of peri-urban areas was similar to that of urban areas. Indicator species were found for all environmental variables. On the basis of the results, we suggest the strategy that would increase the diversity of birds and increase the stability of their populations in urban areas. Urban planners should encourage 1) both forests and parks since they harbour different species of birds, 2) larger green spaces since larger areas have species that are more typical of larger areas and 3) a mosaic of a larger number of smaller forest remnants combined with larger forest complex serving as source areas.
Ključne besede: urban forest, bird species composition, forest remnant, urbanization, peri-urban forest, bird monitoring, species richness
DiRROS - Objavljeno: 14.06.2021; Ogledov: 305; Prenosov: 187
URL Celotno besedilo (0,00 KB)
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99.
Microsites influence the light response of young douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)
Matjaž Čater, 2021

Povzetek: Two comparable sites with uneven-aged mixed forest stands with more than 20% Douglas-fir in the growing stock at an altitude of 650 m a.s.l. were selected. The physiological response of young trees to different light intensities was measured during the main growing season in three consecutive years, and four different light categories, which were determined from hemispherical photographs. The four light intensity categories were defined according to Indirect Site Factor (ISF%): in the open (A-ISF > 35%), at the outer forest edge (B-25% < ISF < 35%), at the inner forest edge (C-15% < ISF < 25%), and under complete canopy under mature forest stand (D-ISF < 15%). Climate data were obtained from the Royal Netherlands Meteorological Institute %Climate Explorer% website. For the intensive micrometeorological observations, four monitoring sites were established along the elevation gradient at each site during summer and late fall to record relative humidity (RH%) and temperature (°C) with a 30 min recording interval sequence. Measured assimilation responses (A) and light use efficiency (%) at one site followed the expected pattern, while humidity combined with microsite conditions proved significant in explaining the specific response of young Douglas-fir to the different light intensity at the other site. For higher survival and optimal future development of Douglas-fir in the changing environment, microsites with higher capacity for storage moisture and favorable microclimate should generally be preferred to exposed and dry sites.
Ključne besede: Douglas-fir, light response, photosynthesis, light use efficiency, silviculture
DiRROS - Objavljeno: 28.05.2021; Ogledov: 340; Prenosov: 219
.pdf Celotno besedilo (1023,09 KB)

100.
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