Search

Evidence of climate change and global warming is becoming more visible; it is an ongoing process that is likely to become increasingly influential in the near future, not only at the global level but also at the local and regional levels. The fact that climate change affects the development of all forest communities and forest tree species, accordingly, has resulted in the increasing awareness in society towards this phenomenon. Having this in mind, the main aim of this paper is to evaluate the relationship between climate change and coniferous forests in the Balkan Peninsula, as well as to review the management strategies that may contribute to forest adaptation to climate change, with a special emphasis on the conservation of forest genetic resources. Hence, we have analyzed 202 papers regarding climate change and its effects on coniferous forests in the Balkan region, as well as papers dealing with adaptive forest management and forest genetic resources conservation. We concluded that climate change will likely represent one of the major challenges for coniferous forests on the Balkan peninsula in the future, imposing a need for the application of different management strategies to address these challenges and to facilitate adaptation of forests to the altered environmental conditions.

In the paper, the structural, production and development characteristics of a potentially overripe and devitalized sessile oak stand on Fruška Gora were investigated. Structural and production characteristics were investigated on the ICP Forests plot Level 2, where data from two surveys in 2015 and 2020 were used. Developmental characteristics were investigated using center cores of 22 dominant sessile oak trees sampled in 2014 and using electronic and manual dendrometers on six trees from 2015 Topola/Poplar 2022, 210, 29-40 www.ilfe.org 30 to 2022. The diameter distribution shows that the researched stand is two-storeyed and mixed, and based on the diameter distribution of the first floor, it was a pure even-aged stand of sessile oak in the past. Productivity in the period from 2015 to 2020 shows stagnation, but with a clear decrease in the share of sessile oak, especially in the total basal area and volume. By analyzing the age and development characteristics, individual trees show clear signs of devitalization during most of their life, and for the whole stand we can conclude that it is significantly too old and in clear devitalization, especially after 2019. The diameter growth in the growing season is characterized by small values and predominantly occurs in May and June. The general conclusion is that the researched stand is overaged, devitalized (the main species of the stand is the sessile oak), with the regression of the sessile oak in relation to other competing species and very slow growth dynamics even on an annual basis, which from the perspective of future management puts the forestry profession in a very unenviable role and requires an adaptive approach to managing such stands.

We analyzed macro-(Ca, Mg, and K) and microelements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in soil from three depths that correspond to different soil horizons (0-60, 61-75, and 76-160 cm) from three sites in Futoški park (Novi Sad, Serbia), which was measured by using the atomic absorption spectrophotometry (AAS). In this study, we tested the influence of spatial arrangement and soil depth on the variation of micro-and macro-element contents using (i) two-way ANOVA with the site, soil depth, and their interactions as dependent variables, (ii) Tukey post-hoc test (for p

In this paper, the occurrence, frequency, and character of stormy winds in clonal poplar plantations in Vojvodina Province were studied in the period from 2016-2021 years. 10 large gusts of stormy winds were recorded, which caused enormous damage to poplar plantations. Depending on the strength of the wind, the age of the plants, and the state of soil moisture, the damage was reflected in windbreaks, windbreaks, and wind bending of trees.

Primary forests, defined here as forests where the signs of human impacts, if any, are strongly blurred due to decades without forest management, are scarce in Europe and continue to disappear. Despite these losses, we know little about where these forests occur. Here, we present a comprehensive geodatabase and map of Europe’s known primary forests. Our geodatabase harmonizes 48 different, mostly field-based datasets of primary forests, and contains 18,411 individual patches (41.1 Mha) spread across 33 countries. When available, we provide information on each patch (name, location, naturalness, extent and dominant tree species) and the surrounding landscape (biogeographical regions, protection status, potential natural vegetation, current forest extent). Using Landsat satellite-image time series (1985–2018) we checked each patch for possible disturbance events since primary forests were identified, resulting in 94% of patches free of significant disturbances in the last 30 years. Although knowledge gaps remain, ours is the most comprehensive dataset on primary forests in Europe, and will be useful for ecological studies, and conservation planning to safeguard these unique forests., Measurement(s)Geographic DistributionTechnology Type(s)digital curationFactor Type(s)countrySample Characteristic - Environmentprimary forestSample Characteristic - LocationEurope Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.14540625

Russian made FPM-GMO-1.6 flotation machines were previously installed for primary stage flotation concentration of lead and zinc minerals in Lece flotation plant. For cleaning stage FMR-10 flotation machines were in use. Beside low technological characteristic, hard maintenance and worn out are characteristic of this machines. In order to modernize the production and eliminate the above shortcomings primarily in the process of lead minerals flotation, in 2020, the old flotation cells were replaced with new ones. Currently, 8 new RCS-5 cells for coarse and scavengel flotation of lead minerals and 4 RCS-3 cells for cleaning of coarse lead mineral concentrate are working on the lead flotation line in Lece flotation. These cells were produced by Metso Minerals from Finland. Flotation cells, which are installed, have modern technical - technological characteristics, with all the accompanying equipment for automatic control of pulp levels and air consumption. This paper presents comparative characteristics of old and new flotation cells, their appearance and characteristics and technological results achieved in flotation with old and new cells.

In this paper we compared the accuracy of different samples (minus the sample with the NN1 edge correction and buffer zone, plus sample and modified cluster sample) to determine indices of spatial structure in beech forests in Serbia, which can be used in regular forest inventory. The research was conducted in 11 forest stands of different structure at the territory of Central Serbia. Field data used for the assessment of spatial structure indices were collected across the examined stands on the sample plots of different sizes, using systematic grid, with the square layout of sample plots (100x100 meters). The study was conducted on 242 sample plots. For accuracy comparison of different sample types, five indices were used: Uniform angle index, Mean directional index, Species mingling index, DBH differentiation and DBH dominance indices. One-way ANOVA showed that at the stand level there were no statistically significant differences between mean values of indices obtained by different sample types. However, Simple linear correlations confirmed for most indices that if the spatial structure is to be determined with accuracy at the level of sample plots (in this case, a circular fixed radius plot of 5 acres) it is necessary to use a plus sample during data collection. For species mingling and DBH differentiation indices, Simple linear correlations show that both minus sampling with edge correction buffer zone and modified cluster sampling with somewhat less accuracy can be used to a certain extent. Minus sampling with NN1 edge correction is not practical for use on sample plots of this size in beech forests in Serbia.

Climate anomalies significantly shape forests around the World. Intensive climate changes (global warming and drought) that have occurred since 20th century have caused more extreme climate events and boosted forest mortality. Different drought resistance in the Quercus sp. was observed among species and tree populations up to the genotype level. Species-specific responses to drought further complicate the understanding of the drought-induced changes in forests. We selected 20 radial growth and six stable carbon isotope ratio (δ13C) chronologies of Quercus cerris and Q. robur from Serbia. Since both δ13C and radial growth chronologies are influenced by surrounding stressors, including nonlinear climate trends, a more flexible approach to their modeling was required, and we, therefore, chose a generalized additive mixed model (GAMM) for data processing. A total of 20 climate and environmental variables were included in models to better understand their relationship and climate predictions/reconstruction.In the GAMM, a better fit was obtained for δ13C and more xeric Q. cerris (adj. R2 0.646) than for radial growth and Q. robur GAMMs performances. The potential for predicting radial growth and δ13C based on 20 different climate and environmental variables was tested with GAMM. Chronologies were split into two subsets for GAMM calibration and validation. GAMM predictions were calibrated using the first 25 years (1961-1985), while the second subset (1986-2010) was used for model validation. Both oak species showed higher similarity between measured and predicted δ13C, opposite of radial growth. A xeric oak species (Q. cerris) showed higher sensitivity to climatic and environmental factors, reflected in better GAMM prediction potential.Species-specific differences in radial growth and δ13C were observed. The results presented in this study suggest that xeric oak species such as Q. cerris are more sensitive to environmental factors in both δ13C and radial growth. According to the GAMM results, the more climate-sensitive Q. cerris showed better relationships with the analyzed factors than Q. robur. It was concluded that δ13C responds more strongly and quickly to climatic anomalies than TRW and that the analyzed climatic and environmental factors can be a reliable indicator of cambial productivity and stress periods of both oak species. Keywords: Dendrochronology, Dendrochemistry, Stable carbon isotope, Tree ring, Quercus, Drought, GAMM. Acknowledgments: This research was supported by the Science Fund of the Republic of Serbia, PROMIS, #6066697, TreeVita. TL acknowledge the financial support from the Slovenian Research Agency - research core funding No. P4-0107 Program research group “Forest Biology, Ecology and Technology” and research grant J4-8216 “Mortality of lowland oak forests - consequence of lowering underground water or climate change?”Note: This contribution is a summary of a study by Kostić S, Levanič T, Orlović S, Matović B, Stojanović DB. Xeric Turkey oak (Quercus cerris L.) is a more reliable climate indicator than hydric pedunculate oak (Q. robur L.) in the same stand conditions: Stable carbon isotope ratio (δ13C) and radial growth approaches (In press)

Acontia melanura (Tauscher, 1809) is an Eurasian noctuids species. It is present in Eastern Romania (Bleak Sea coastal area) and Bulgaria, as well as in southeastern European part of Russia, including the southern Urals. In 2019 and 2020, A. melanura was found in northeastern Serbia at the locality Korn in the Special Nature Reserve "Deliblatska peščara", and this was the westernmost finding of this species in Europe. A. melanura is considered as a vulnerable species in the Red List of Noctuidae of Serbia. However, it is mistakenly confused (due to disputed taxonomic affiliation) with Acontia urania (Frivaldsky, 1835), which was declared as the one of two extinct species in this list. This research proves the existence of A. melanura in Banat, with presented overview of the localities and dates of findings of the species. Also, the similarity of the spread of A. melanura and related species Ponemetia candefacta (Hübner, [1831]) in the Republic of Serbia in the light of climate change was pointed out.

41 50 43 2022 M50 М51 Рудник Леце је карактеристичан по томе што у флотацијским концентратима олова и цинка као корисну примену има злато и сребро. Практично од отварања рудника и флотације трају истраживања и борба за што боље технолошке показатеље на сва четири платива метала (олово, цинк, злато и сребро) посебно на злату. Овај рад представља допринос тој борби у циљу повећања искоришћења злата. Како је начин појављивања злата веома различит (самородно, са оловом и цинком, са пиритом и кварцом) то је и технолошка шема валоризације злата мора бити сложена. Највећи део злата је везан за галенит и валоризује се кроз концентрат олова. Мањи део злата је везан за цинк и валоризује се кроз концентрат цинка. Међутим, око 25% злата остаје у јаловини и то је био мотив истраживачима тј. ауторима овог рада да део злата који се губи у јаловини покушају да валоризују кроз трећи концентрат пирита са повећаним садржајем злата. У раду су приказани резултати лабораторијских испитивања могућности добијања концентрата пирита из јаловине Леце и предлог технолошке шеме процеса The Lece mine is characterized by the fact that it has gold and silver besides the main valuable components in the flotation concentrates of lead and zinc. Practically since the opening of the mine and flotation, research has been carried out with the aim of obtaining better technological indicators on all four valuable metals (lead, zinc, gold and silver), especially on gold. This paper represents a contribution to that research in order to increase the recovery of gold in flotation concentrates. Gold occurs in ore in several ways (native, with lead and zinc, with pyrite and quartz), which requires a complex technological scheme of gold valorization. Most of the gold is bound to galena and is valorized through lead concentrate. A smaller part of the gold is bound to zinc and is valorized through zinc concentrate. However, about 25% of the gold remains in tailings. Researchers ie. the authors of this paper tried to valorize part of the gold that is lost in the tailings by introducing a third pyrite concentrate with an increased gold content.The paper presents the results of laboratory experiments on the possibility of obtaining pyrite concentrate from the Lece tailings and a proposal for a technological scheme of the process.

We analysed sapwood characteristics in 344 pedunculate oak (Quercus robur L.) samples from the south-western part of the Pannonian Basin. The samples came from 13 sites, located in Slovenia, Croatia and Serbia. The trees had an average of 13.3 sapwood rings, with a minimum of 5 and maximum of 32. Fifteen log-log linear regression models were employed to assess the statistical relationship between sapwood and heartwood variables. The number of sapwood rings (NSW), which is usually needed in dendroarchaeological dating, is significantly related to the number of heartwood rings (NHW), heartwood width (WHW) and heartwood growth rate (GHW). Older and more slowly growing trees had a higher average number of sapwood rings. Using NHW and WHW, we employed an additional multiple regression model and calculated coefficients for NSW predictions for real-world dendroarchaeological dating from the south-western part of the Pannonian Basin.

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.

New technologies, such as satellites and sensors, provide a wealth of new information about all ecosystems. In dendrochronological studies, all drought-related factors are of great importance for a more comprehensive understanding of associations between radial growth and water loss. Soil moisture directly reflects the wetness of immediate root surroundings, which is vital to the water uptake by trees. Owing to the advances in satellite observation systems and sensors, soil moisture (SM) can be remotely measured, opening new window in dendrochronological research.Using the pedunculate oak (Quercus robur L.) lowland SE Europe forests dataset, which count 23 stands and more than 300 tree ring width (TRW) series, we observed reliable associations between satellite-based SM and TRW. Specifically, we observed different TRW−SM patterns based on the precipitation regime. SM in the hottest months (July and August) boosted radial growth, whereas opposite results were noted in the wettest spring months oaks that growing in wetter stands. Unlike oaks from drier and wetter stands that exhibited strong response to SM, those growing on moderately wet (optimal) stands are less sensitive to SM, making these stands optimal oak surroundings.On the other hand, by applying a Generalized Additive Mixed Model (GAMM), we noted moderate−weak interactions between TRW series and smoothed SM timescales, with stronger deviations in extreme dry/wet years. Based on the TRW sensitivity to SM findings, which were interpreted via Pearson’s correlation technique and GAMM modeling, strong relations can be inferred, and SM can be labelled as reliable pedunculate oak driver.Keywords: Forestry, Remote sensing, Dendrochronology, Soil moisture, Pedunculate oak, GAMMAcknowledgments: This research was supported by the Science Fund of the Republic of Serbia, PROMIS, #6066697, TreeVita.Note: This contribution is a summary of a study by Kostić S, Wagner W, Orlović S, Levanič T, Zlatanov T, Goršić E, Kesić L, Matović B, Tsvetanov N, Stojanović DB. Different tree-ring width sensitivities to satellite-based soil moisture from drier, moderate and wetter pedunculate oak (Quercus robur L.) stands across a southeastern distribution margin (In press)

Associations of pedunculate oak (Quercus robur L.) radial growth with satellite-based soil moisture (SM) during the intensive tree growth period over a 30-year time span (1980-2010) were analyzed. This study included tree-ring width (TRW) chronologies from 22 stands located in four southeastern (SE) European countries (Slovenia, Croatia, Serbia and Bulgaria), which were grouped into three wetness groups (WGs): dry (750 mm), following the annual sum of precipitation. High correlation strengths during the intensive growth period-late spring and early summer months (April to June) was noted, which was opposite to the trend in late summer months. Variations in detrended TRW (TRWi) sensitivity to SM were also observed among the WGs. Specifically, the TRWi chronologies from the dry and wet WGs provided a greater number of significant correlations (p < 0.01) than trees from the moderate WG did. In wetter stands, TRWi correlated more negatively in the wettest (spring) months, while the correlation was weaker in summer months; these trends were opposite to those of trees growing in drier conditions that had the strongest responses to SM. A generalized additive mixed model (GAMM) based on 38 variables indicated that the fit for SM and radial growth was as strong as the fits for other traditionally measured parameters (temperature, precipitation, and river water level) and calculated drought indices (standardized precipitation index and the Ellenberg index) and TRW. Additionally, radial growth chronologies from drier sites had stronger fits with surrounding environmental factors. In conclusion, our findings suggest that SM can potentially be used as a reliable remote sensing indicator of the soil wetness in oak forests, which affects tree productivity and radial growth patterns and provides a new opportunity in dendrochronology research on larger scales.

Erebia aethiops (Esper, 1777) is an Eurasian butterfly species. Results of the previous studies revealed the presence of only four species belonging to the genus Erebia (Dalman, 1816) on Kopaonik mountain (Mt. Kopaonik), including Erebia ligea (Linnaeus, 1758), Erebia euryale (Esper, 1805), Erebia medusa (Denis & Schiffermüller, 1775) and Erebia ottomana (Herrich-Schäffer, 1847). A recent finding of the species Erebia oeme (Hübner, 1804) pointed to insufficient research of this group of mountain butterflies on Mt. Kopaonik. This is confirmed by the last finding of Erebia aethiops (Esper, 1777) on two locations at high elevations of Mt. Kopaonik.

Extreme weather conditions, namely droughts, heat waves, heavy rains, floods, and landslides are becoming more frequent globally and in Serbia as a result of climate change. Generally, various parts of human society are affected by changing climate conditions. Forest ecosystems are one of the most sensitive systems to weather and climate. In that sense, small changes may lead to large disturbances including forest decline, outbreaks of insect pests and diseases and eventually mortality. In Serbia, the average temperature in forest ecosystems of the most important and abundant forest tree species has risen for more than 1°C in the last thirty years (1990-2019) in comparison to the previous period (1961-1990). During the last thirty years, the northern and western parts of Serbia experienced an increase in precipitation as opposed to the southern and eastern parts of the country. If one takes a closer look at the climate within a particular forest stands, it would seem that the effect of precipitation decrease is stronger in less humid parts of a tree species range. In this paper, we discuss various aspects of climate change impacts on forests and forestry, including forest ecology, genetics, physiology, pests and diseases, ground vegetation, monitoring, reporting and verification system, climate change litigation and perspectives of forests in the 21st century in Serbia.

Centro de Investigación Forestal (CIFOR), Spruce-fir-beech mixed forests cover a large area in European mountain regions, with high ecological and socio-economic importance. As elevation-zone systems they are highly affected by climate change, which is modifying species growth patterns and productivity shifts among species. The extent to which associated tree species can access resources and grow asynchronously may affect their resistance and persistence under climate change. Intra-specific synchrony in annual tree growth is a good indicator of species specific dependence on environmental conditions variability. However, little attention has been paid to explore the role of the inter-specific growth asynchrony in the adaptation of mixed forests to climate change. Here we used a database of 1790 tree-ring series collected from 28 experimental plots in spruce-fir-beech mixed forests across Europe to explore how spatio-temporal patterns of the intra- and inter-specific growth synchrony relate to climate variation during the past century. We further examined whether synchrony in growth response to inter-annual environmental fluctuations depended on site conditions. We found that the inter-specific growth synchrony was always lower than the intra-specific synchrony, for both high (inter-annual fluctuations) and low frequency (mid- to long-term) growth variation, suggesting between species niche complementarity at both temporal levels. Intra- and inter-specific synchronies in inter-annual growth fluctuations significantly changed along elevation, being greater at higher elevations. Moreover, the climate warming likely induced temporal changes in synchrony, but the effect varied along the elevation gradient. The synchrony strongly intensified at lower elevations likely due to climate warming and drying conditions. Our results suggest that intra- and inter-specific growth synchrony can be used as an indicator of temporal niche complementarity among species. We conclude that spruce-fir-beech mixtures should be preferred against mono-specific forests to buffer climate change impacts in mountain regions., This study was supported by the COST Action CLIMO (Climate-Smart Forestry in Mountain Regions – CA15226) financially supported by the EU Framework Programme for Research and Innovation HORIZON 2020. This publication is also part of a project that has received funding from the European Union’s HORIZON 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 778322 (CARE4C)., 10 Pág.

Severe droughts have the potential to reduce forest productivity and trigger tree mortality. Most trees face several drought events during their life and therefore resilience to dry conditions may be crucial to long-term survival. We assessed how growth resilience to severe droughts, including its components resistance and recovery, is related to the ability to survive future droughts by using a tree-ring database of surviving and now-dead trees from 118 sites (22 species, >3,500 trees). We found that, across the variety of regions and species sampled, trees that died during water shortages were less resilient to previous non-lethal droughts, relative to coexisting surviving trees of the same species. In angiosperms, drought-related mortality risk is associated with lower resistance (low capacity to reduce impact of the initial drought), while it is related to reduced recovery (low capacity to attain pre-drought growth rates) in gymnosperms. The different resilience strategies in these two taxonomic groups open new avenues to improve our understanding and prediction of drought-induced mortality., Resilience to drought is crucial for tree survival under climate change. Here, DeSoto et al. show that trees that died during drought were less resilient to previous dry events compared to surviving conspecifics, but the resilience strategies differ between angiosperms and gymnosperms.

In Europe, mixed mountain forests, primarily comprised of Norway spruce (Picea abies (L.) Karst.), silver fir (Abies alba Mill.), and European beech (Fagus sylvatica L.), cover about 10 × 106 ha at elevations between ∼600 and 1600 m a.s.l. These forests provide invaluable ecosystem services. However, the growth of these forests and the competition among their main species are expected to be strongly affected by climate warming. In this study, we analyzed the growth development of spruce, fir, and beech in moist mixed mountain forests in Europe over the last 300 years. Based on tree-ring analyses on long-term observational plots, we found for all three species (i) a nondecelerating, linear diameter growth trend spanning more than 300 years; (ii) increased growth levels and trends, the latter being particularly pronounced for fir and beech; and (iii) an elevation-dependent change of fir and beech growth. Whereas in the past, the growth was highest at lower elevations, today’s growth is superior at higher elevations. This spatiotemporal pattern indicates significant changes in the growth and interspecific competition at the expense of spruce in mixed mountain forests. We discuss possible causes, consequences, and silvicultural implications of these distinct growth changes in mixed mountain forests.

Revisión e identificación de oportunidades de investigación en modelización de la dinámica de masas mixtas, Aim of study: Modelling of forest growth and dynamics has focused mainly on pure stands. Mixed-forest management lacks systematic procedures to forecast the impact of silvicultural actions. The main objective of the present work is to review current knowledge and forest model developments that can be applied to mixed forests. Material and methods: Primary research literature was reviewed to determine the state of the art for modelling tree species mixtures, focusing mainly on temperate forests. Main results: The essential principles for predicting stand growth in mixed forests were identified. Forest model applicability in mixtures was analysed. Input data, main model components, output and viewers were presented. Finally, model evaluation procedures and some of the main model platforms were described. Research highlights: Responses to environmental changes and management activities in mixed forests can differ from pure stands. For greater insight into mixed-forest dynamics and ecology, forest scientists and practitioners need new theoretical frameworks, different approaches and innovative solutions for sustainable forest management in the context of environmental and social changes., COST Action FP1206 EuMIXFOR (COST Association, European Comission), APVV-0480-12 and APVV-15-0265 (Slovak Research and Development Agency) and AGL-2014-51964-C2-1-R (Spanish Ministry of Economy and Competitiveness).

Understanding intraspecific genetic variation is one of the principal requirements for the evaluation of tree species capacity to cope with intensive climatic changes, as well as designing long-term conservation programs. Herein, we evaluated the genetic diversity and genetic structure of seven pedunculate oak (Quercus robur L.) populations, located at the southern margin of its distribution range on the Balkan Peninsula (Serbia). The objective of the study was to propose future in situ conservation measures aimed at protection of pedunculate oak adaptive and neutral genetic diversity at the species rear-edge. Genetic diversity and structure were estimated using twelve highly polymorphic simple sequence repeat (SSR) markers. The mean expected heterozygosity (He) was 0.769, allelic richness (AR) 9.63, and private allelic richness (pAR) 0.79, indicating high genetic diversity in the studied populations. Genetic differentiation among the populations was low (Fst = 0.032). Structure analysis, the unweighted pair group method with arithmetic mean (UPGMA) showed the existence of two gene pools unrelated to the populations’ area of occurrence. Taking into consideration the results of the current study and previous conservation activities on the pedunculate oak in Serbia, as well as the importance of rear-edge populations in the long-term conservation of the species genetic diversity, we suggested establishing three additional gene conservation units for securing long-term sustainability of the species.

This paper presents an analysis of the radial growth, tree dimensions, and allometry of three phenological pedunculate oak (Quercus robur L., QURO) varieties (early (E-QURO), typical (T-QURO), and late (L-QURO)), from a common garden experiment. We focused on the resistance and resilience of each variety to drought events, which occurred in 2012 and 2017, as well as their recovery potential during juvenile and mature growth phases, with the goal of clarifying how QURO drought sensitivity is influenced by tree phenology and growth stage. Our results indicate that E-QURO is more drought resistant, while T-QURO and L-QURO exhibit greater recovery potential after a drought event. Hence, typical and late QURO varieties are better prepared to withstand climate change. We also noted differences in the physical dimensions and the allometry of the studied QURO varieties. On average, 21-year-old QURO specimens from the analyzed stand are 9.35 m tall, have a crown width (CW) of 8.05 m, and a diameter at breast height (DBH) of 23.71 cm. Although T-QURO varieties had the greatest DBH and CW, they were shorter than E- and L-QURO, which are similar in height. T-QURO is also shorter relative to DBH, while L-QURO has a wider crown relative to tree height (TH). Intra-variety variations are higher than variations among half-sib (open-pollinated) families of each variety. Moreover, the adopted regression model provided a better fit to the CW/DBH ratio than to TH/DBH and CW/TH.

Soil properties, drought, and the interaction between the two are significant, if unclear, driver of radial growth variations. We observed that, soil properties exert a stronger effect on pedunculate oak (Quercus robur L.; QURO) radial growth sensitivity to drought (interpreted via Standardized Precipitation Evapotranspiration Index; SPEI), than on radial increment and its variations. Soils that are strongly affected by soil water (typical and haplic gleysol) provide the most suitable substrates for QURO radial growth during drought events because they provide more continuous water sources. In contrast, QURO growing on chernozem (with sand) and solonetz (highly saline soils) are more drought-sensitive and have smaller radial increments. The influence of soil type is clearly evident in the pattern of QURO decline that has occurred across Europe (2014) and Serbia (2011–2012): QURO growing on gelysols (characterized by high soil water content) were not strongly affected, whereas marked mortality occurred in QURO forests growing on chernozem and solonetz. Based on the findings yielded by the Generalized Additive Mixed Model (GAMM) and the Linear Mixed Effects Model (LMM), the above-ground (precipitation and temperature) and below-ground (river water level and soil moisture) drought sources affect radial growth equally and its sensitivity to drought. Overall, GAMM better fitted with analyzed radial growth properties, than LMM. Likewise, based on the GAMM and LMM outputs, stronger associations between QURO radial growth sensitivity to drought and nine climate parameters were obtained compared with raw as well as detrended radial growth series.

Background and Purpose: Water stress is one of the major problems for urban trees. It affects a wide range of plant responses, from changes at the cellular level to the reduction in growth rates. Irrigation of trees in urban areas may provide numerous benefits important for increasing tree vitality to withstand other stresses that might occur. The aim of this study was to compare drought effects on some physiological and biochemical performances of Pedunculate oak (Quercus robur L.) and Hornbeam (Carpinus betulus L.) saplings grown in the urban area. Materials and Methods: The study was conducted during August 2012 at the Boulevard of Europe (Novi Sad, Republic of Serbia). Measurements were carried out on saplings grown in the part of the boulevard with drip irrigation system installed (Site 1) and on the saplings cultivated in the part without any irrigation system (Site 2). Results: Soil moisture content was significantly higher at Site 1 with approximately 57.2%, compared to 18.7% at Site 2. The results showed that irrigated saplings were characterized by significantly higher stomatal conductance in Q. robur and C. betulus. Similarly, the content of free proline, FRAP units and the amount of malonyldialdehyde showed increased values in trees subjected to soil water deficit. In contrast, net photosynthesis, chlorophyll and carotenoid contents did not differ notably in irrigated and non-irrigated Q. robur and C. betulus trees. Conclusions: Water stress significantly affected stomatal conductance and some biochemical properties of Q. robur and C. betulus saplings cultivated at the non-irrigated site. The results showed that the implementation of drip irrigation system in urban landscape is an important tool in the prevention of drought stress effects on the physiological processes of plants.

An adequate approach to diagnosis and treatment of the dominant thyroid nodule is a matter of debate. The aim of the study is to determinate the most significant ultrasaund and scintigraphic parametars of malignancy in dominant thyroid nodules. The study involved 95 patients treated surgically for polynodous goiter with a dominant nodule for whom ultrasonographic and scintigraphic diagnosis was made prior to surgery. Echosonographic and scintigraphic findings were compared and analyzed against the operative and histopathologic findings of the dominant nodule. Our male examinees were 59.4 ± 11.66 years, and female examinees 53.02 ± 12.78 old on the average. Of the total number of examinees, there were 74 with benign and 21 with malignant changes. Considering the ultrasound and scintigraphy parameters of malignancies, the following could be singled out as statistically significant: non-sharply delineated nodule change (OR = 0.765; 95% CI = 0.555-0.985); hypoechogenicity (OR = 2.152; 95% CI = 1.111-2.456); avascular nodule (OR = 2.156; 95% CI = 1.111-4.589); and hypofunctional nodule (OR = 2.154; 95% CI = 1.111-3.589). The sensitivity and specificity of ultrasound in dominant nodule detection were 80% and 90%, respectively, while for scintigraphy the percentages were 55% and 60%. The most important diagnostic parameters of a malignancy of the dominant thyroid nodule are non-sharp delineation of the change, hypoechogenicity and nodule avascularization. Ultrasound has higher sensitivity and specificity than scintigraphy in the diagnosis of malignant dominant thyroid nodules.

Changing climatic conditions can have various consequences for forest ecosystems, from increasing frequencies of forest fires, ice and windstorm events to pathogen outbreaks and mass mortalities. The Standardized Precipitation Index (SPI) was chosen for the evaluation of drought impact on the radial growth of trees after extensive preliminary testing of various calculated monthly climate parameters from the CARPATCLIM database. SPI was calculated for periods between 3 and 36 months for different sites (lowland and mountainous parts of Serbia, Southeast Europe), from which Quercus robur, Q. cerris, Fagus sylvatica and Pinus sylvestris samples were acquired. Bootstrapped Pearson%s correlations between SPI monthly indices and radial growth of tree species were calculated. We found that 12-month SPI for summer months may be a good predictor of positive and negative growth of different species at different sites. The strongest positive correlations for five of six tree-ring width chronologies were between 12-month June and 14-month September SPI, which implies that high growth rates can be expected when the autumn of the previous year, and winter, spring and summer of the current year, are well supplied with precipitation, and vice versa (low precipitation in given period/low growth rates). Nasl. z nasl. zaslona. Opis vira z dne 21. 2. 2018. Soavtorji: Tom Levanič, Bratislav Matović, Stefan Stjepanović, Saša Orlović. Bibliografija: str. 107-110. Abstract.

Research into mixed-forests has increased substantially in the last decades but the extent to which the new knowledge generated meets practitioners' concerns and is adequately transmitted to them is unknown. Here we provide the current state of knowledge and future research directions with regards to 10 questions about mixed-forest functioning and management identified and selected by a range of European forest managers during an extensive participatory process. The set of 10 questions were the highest ranked questions from an online prioritization exercise involving 168 managers from 22 different European countries. In general, the topics of major concern for forest managers coincided with the ones that are at the heart of most research projects. They covered important issues related to the management of mixed forests and the role of mixtures for the stability of forests faced with environmental changes and the provision of ecosystem services to society. Our analysis showed that the current scientific knowledge about these questions was rather variable and particularly low for those related to the management of mixed forests over time and the associated costs. We also found that whereas most research projects have sought to evaluate whether mixed forests are more stable or provide more goods and services than monocultures, there is still little information on the underlying mechanisms and trade-offs behind these effects. Similarly, we identified a lack of knowledge on the spatio-temporal scales at which the effects of mixtures on the resistance and adaptability to environmental changes are operating. Our analysis may help researchers to identify what knowledge needs to be better transferred and to better design future research initiatives meeting practitioner's concerns. This article is based upon work from COST Action FP1206, EuMIXFOR, supported by COST (European Cooperation in Science and Technology). The authors want to specially thank the large number of forest managers that were involved in the participatory process and kindly responded to the surveys. The first author also thanks the Spanish Ministry of Economy and Competitiveness for funding the project AGL2015-70425-R which partly supported his contribution to this study. MM acknowledges support by grant IUT21-4 of the Estonian Ministry of Education and Research and DS support by project III 43007 (2011–2017) from Ministry of Education, Science and Technological Development of Republic of Serbia.

Currently, about 70% of the forest land in Europe is covered by stands composed of two or more tree species. The similar situation can be found outside Europe too. While forest management of monocultures is well described, multispecies forests still need a better understanding to develop appropriate forest practice. Managing mixed forests can be more complex than managing monocultures because of the need to optimize the provision of multiple benefits according to the societal demands including sustaining biodiversity and ecosystem functioning. In this chapter we are going to present (1) the most important and well-described tree species combinations found in each participating countries taking biogeographical region in Europe into account, (2) the main management objectives of those mixtures, (3) the silvicultural approaches that are available for the particular mixed-species forests and (4) the main challenges experienced in mixed-species forest management. We synthesized information about management of mixed-species forests based on questionnaires received from both European countries and few countries from outside Europe participating in COST Action ‘EuMIXFOR’. The survey revealed that (i) the main management objective in the analysed mixtures is valuable timber production followed by protection of soil and water and protection of forests against disturbances, (ii) the uniform shelterwood is the most widespread regeneration method followed by the clear-cutting and the irregular shelterwood system, (iii) the crown thinning followed by low thinning is the most frequent thinning method, and (iv) the main challenge of management is high game pressure and the lack of management rules covering mixture growth and taking into account both species functional traits and site conditions.

This study presents results of the comparison of structural and production characteristics of managed and virgin European beech forests in Serbia. Five managed and three virgin European beech stands were studied. The aim of this research was to determine the impact of the previous forest management on the structural diversity and production characteristics of managed European beech high forests in Serbia. The observed stands are located in the mountainous range of 400 to 1200 meters above sea level in the areas with the most productive beech forests in Serbia. Structural characteristics were compared using the following parameters: Height curves, Diameter distribution, Gini index, Coefficient of variation, Slenderness coefficient and maximum dimensions of standing living and dead trees. Stand density and productive characteristics were studied using the following forest estimation elements: number of trees, basal area, volume, biomass, carbon stock, stand quadratic mean diameter, Lorey’s mean height and volume of dead wood. The greatest differences were found in the dimensions of the largest trees in managed and virgin beech forests (diameters at breast height and heights). Certain differences were found in the shape of Height curves and Diameter distribution and in the values of Slenderness coefficient. However, the Gini index and the Coefficient of variation show that these managed beech forests in Serbia substantially preserve the primeval structural diversity. The differences in the average value of most forest estimation elements of managed beech high forests in Serbia compared to virgin beech forests are statistically significant, which tells us that the previous management had a significant impact on the changes in the production characteristics of these forests in Serbia., U radu se prikazuju rezultati usporedbe strukturnih i proizvodnih karakteristika bukovih sastojina gospodarskog i prašumskog tipa u Srbiji. Istraživano je pet sastojina gospodarskog i tri sastojine prašumskog tipa. Cilj ovog istraži­va­nja bio je utvrditi utjecaj prethodnog gospodarenja šumama na strukturnu raznolikost i proizvodne osobine visokih bukovih šuma u Srbiji. Istraživane sastojine nalaze se u planinskom rasponu od 400 do 1200 metara nadmorske visine u područjima gdje se nalaze najproduktivnije bukove šume u Srbiji (slika 1 i tablica 1). Strukturne karakteristike uspore­đe­ne su pomoću sljedećih parametara: visinske krivulje, debljinska struktura, Gini indeks, koeficijent varijacije, koeficijent vitkosti i maksimalne dimenzije dubećih živih i mrtvih stabla. Sastojinsku gustoću i produktivne osobine proučavane su pomoću sljedećih procijenenih taksacijskih elemenata: broj stabala, temeljnica, volumen, biomasa, zaliha ugljika, srednji promjer po temeljnici, Lorajeva srednja visina i volumen mrtvog drveta. Najveće razlike pronađene su u dimenzijama najvećih stabala u bukovim sasatojinama gospodarskog i prašumskog tipa (tablica 4). Određene razlike pro­na­đene su u obliku visinskih krivulja i debljinskoj strukturi, i vrijednostima koeficijenta vitkosti (slike 2, 3, 4 i 5, i tablica 3). Međutim, Ginijev indeks i koeficijent varijacije pokazuju da su bukove sastojine gospodarskog tipa u Srbiji u velikoj mjeri sačuvale iskonsku strukturnu raznolikost (tablica 2 i slika 6). Razlike u prosječnim vrijednostima taksacijskih elemenata sastojina gospodarskog tipa visokih bukovih šumama u Srbiji u odnosu na sastojine prašumskog tipa su statistički značajne, što nam govori da je prethodno gospodarenje imalo značajan utjecaj na promjene u proizvodnim karakteristikama ovih šuma u Srbiji (tablica 5).

Introduction. Chronic subdural hematoma (CSDH) has a variety of clinical presentations, with numerous neurological symptoms and signs. Hemiparesis is one of the leading signs that potentially indicates CSDH. Objective. Purpose of this study was to determine the threshold (cut-off) value of midsagittal line (MSL) shift after which hemiparesis is likely to appear. Methods. The study evaluated 83 patients with 53 unilateral and 30 bilateral CSDHs in period of three years. Evaluated computed tomography (CT) findings in patients with CSDH were diameter of the hematoma and midsagittal line shift, measured on non-contrast CT scan in relation with occurrence of hemiparesis. Threshold values of MSL shift for both types of CSDHs were obtained as maximal (equal) sensitivity and specificity (intersection of the curves). Results. MSL is a good predictor for hemiparesis occurrence (total sample, AUROC 0.75, p=0.0001). Unilateral and bilateral CSDHs had different threshold values of the MSL for hemiparesis development. Results suggested that in unilateral CSDH the threshold values of MSL could be at 10 mm (AUROC=0.65; p=0.07). For bilateral CSDH the threshold level of MSL shift was 4.5 mm (AUROC=0.77; p=0.01). Conclusion. Our study pointed on the phenomenon that midsagittal line shift can predict hemiparesis occurrence. Hemiparesis in patients with bilateral CSDH was more related to midsagittal line shift compared with unilateral CSDH. When value of midsagittal line shift exceed the threshold level, hemiparesis occurs with certain probability.

A new type of layered photonic structure, whose alternating layers are filled with randomly dispersed nano-spheres, is fabricated and its optical properties are experimentally and theoretically analysed. Structures are made on a pullulan doped with chromium ions (dichromated pullulan - DCP) using holography. We found that experimental structures are similar to those observed on wings of the Diachrysia chrysitis moth, having layers of overlapping scales. DCP photonic structure has alternating air-pullulan layers, held in place by sparsely separated nano-pillars, and air voids filled with 30 – 60 nm diameter nanospheres which act as scatterers. Theoretical analysis of such structures shows that the scattering and interference interact to enhance the local field within the layers and increase the residual absorption of the material. We compare optical properties of moth scales with properties of structures fabricated in DCP, and calculated from the functional model.

This paper is a review presenting research results on the forest ecosystems of Serbia that are carried out at the Institute of Lowland Forestry and Environment (University of Novi Sad, Serbia) in the context of climate change and globalisation. The review displays results of the long-term monitoring of the forest ecosystems, where the data were obtained at the permanent experimental trials of IPC-Forests (level 2) and the iLTER's network. All findings are systematically divided according to the research disciplines and the most important tree species (poplar, willow, oak, wild cherry and European beech). Also the aspects of social sciences are included (meaning evaluating forest institutions in the first place). This review is meant to contribute inputs to the ongoing discussion about the achievement of the Millenium Goals of Sustainable Development in the context of Serbian forestry. [Projekat Ministarstva nauke Republike Srbije, br. III 43002: Biosenzing tehnologije i globalni system za kontinuirano istraživanje i integrisano upravljanje ekosistemimai br. III 43007: Istraživanje klimatskih promena i njihovog uticaja na životnu sredinu - pracenje uticaja, adaptacija i ublažavanje -Unapređenje gajenja nizijskih suma i FP7 - STREPOW; FP7 - RoK-FoR; FP7 - EXPEER i IPA - OXIT]

Ellenberg's climate quotient (EQ), which is a simple biometeorological index, was used to predict the xeric limit of the European beech distribution and potential future changes in Serbia (southeast Europe). The general aim of this study was to evaluate EQ as a predictive tool of the xeric limit of the beech at the southern edge of its distribution and to predict future changes in the xeric limit. The novelty of this study is its assessment of EQ accuracy for Serbia, the beech populations of which were separated from Central European refugia during the last glacial period. Climate projections from the coupled regional climate model EBU-POM were used to predict the changes in the xeric limit in the 21st century. The computation of the area under the receiver operating characteristic curves showed that EQ had “good” and “fair” predictive ability for two samples. Using three threshold criteria and different samples, the beech xeric limit in Serbia for the reference period of 1961–1990 varied between EQ values of 20.1 and 29.5. Significant changes in the beech xeric limits were predicted for the 21st century. The EQ calculations for 2001–2030 (A1B scenario) predicted that more than 20% of the present-day beech forests will be located outside of the ideal bioclimatic niche characterised by EQ ≤ 30 that was proposed by Ellenberg. For 2071–2100 (A1B and A2 scenarios), up to 90% of the current beech forests are expected to be located outside of that niche, and approximately 50% will be located beyond the limit EQ = 40 for which beech mass mortalities have been observed. The results suggest an urgent need for the development of adaptive forest management strategies for beech in this region.

There is increasing evidence that species diversity enhances the temporal stability (TS) of community productivity in different ecosystems, although its effect at the population and tree levels seems to be negative or neutral. Asynchrony in species responses to environmental conditions was found to be one of the main drivers of this stabilizing process. However, the effect of species mixing on the stability of productivity, and the relative importance of the associated mechanisms, remain poorly understood in forest communities. We investigated the way mixing species influenced the TS of productivity in Pinus sylvestris L.;Fagus sylvatica L. forests, and attempted to determine the main drivers among overyielding, asynchrony between species annual growth responses to environmental conditions, and temporal shifts in species interactions. We used a network of 93 experimental plots distributed across Europe to compare the TS of basal area growth over a 15-year period (1999–2013) in mixed and monospecific forest stands at different organizational levels, namely the community, population and individual tree levels. Mixed stands showed a higher TS of basal area growth than monospecific stands at the community level, but not at the population or individual tree levels. The TS at the community level was related to asynchrony between species growth in mixtures, but not to overyielding nor to asynchrony between species growth in monospecific stands. Temporal shifts in species interactions were also related to asynchrony and to the mixing effect on the TS. Synthesis. Our findings confirm that species mixing can stabilize productivity at the community level, whereas there is a neutral or negative effect on stability at the population and individual tree levels. The contrasting findings regarding the relationships between the temporal stability and asynchrony in species growth in mixed and monospecific stands suggest that the main driver in the stabilizing process may be the temporal niche complementarity between species rather than differences in species’ intrinsic responses to environmental conditions. © 2016 The Authors. Journal of Ecology © 2016 British Ecological Society

Key message This data set provides unique empirical data from triplets of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples. These data contribute to our understanding of mixed stand dynamics. Dataset access at http://dx.doi.org/10.5061/dryad.8v04m. Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/? uuid=b3e098ca-e681-4910-90990e25d3b4cd52&hl=eng.; Key message :This data set provides unique empirical data from triplets of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples.These data contribute to our understanding of mixed stand dynamics.Dataset access at http://dx.doi.org/10.5061/dryad.8v04m.Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/? uuid=b3e098ca-e681-4910-90990e25d3b4cd52&hl=eng.

Following the water regulation along the Danube river, the area of natural forests decreases and the vegetation is fragmented. The goal of the study was to survey the recent phytocenological characteristics of the region of the protected floodplain outside the dam. We surveyed three site types in poplar plantations near Novi Sad. In the poplar plantations phytocoenological relev?s were made. The elevation of the study plantations is between 75 and 76 m a.s.l. The most represented species on the ground layer are the species Dactylis glomerata, Urtica dioica and Rubus caesius identified on the humofluvisol. The most represented species on the sandy part of the fluvisol were Rubus caesius, Solidago serotina, Dactylis glomerata and Equisetum arvense. The loamy form of fluvisol occurs at an elevation of 75.50 m. The most numerous species on the loamy form of the fluvisol in the flooded region were Rubus caesius, Solidago serotina, Polygonum hydropiper, Dactylis glomerata and Urtica dioica. Based on the above data, we determined the differences between ground vegetation in the study areas and in the part of the alluvial plain affected by additional moisture by both floodwater and ground water.

The retrospective study (2002-2007) for human leptospirosis in Vojvodina was undertaken in order to describe the distribution of the disease in relation with some environmental factors. Regarding the presented results, the major detected number of leptospirosis cases concurs with stagnant waters, wetlands, fish pond areas and protected regions, which comprised the basis for mapping of the region in three risk zones: very high risk (incidence rate higher than 5.0), high risk (2.5-5.0) and medium risk of leptospirosis infection (1.0-2.5). During the investigated period, 97 cases were registered with an average of 13.85 cases per year: 2002, 32 cases; 2003, 7; 2004, 22; 2005, 16; 2006, 4 and 2007, 16. Out of these 97 cases only 5 were women. Serovars from 11 presumptive serogroups caused infection, with a predominance of Icterohaemorrhagiae and Bratislava, accounting for 72.72% of cases together. Icterohaemorrhagiae was the commonest infecting serogroup mostly connected with fish ponds. Case fatality ratio was 9.4%.

Cyanobacteria are responsible for poisoning numerous cases of livestock and other animals, but sometimes they induce serious problems in humans. Mass occurrence and blooms of cyanobacteria were studied in rivers, canals, lakes, and accu?mulations that had been examined in Serbia during period 1980-2002. Because of massive blooming of cyanobacteria, when they produce cyanotoxins, which could be responsible for poisoning, and damage of organs, studies are steered to better understanding cyanotoxins effects on human health. The investigation on microcystins, as one of many cyanotoxins, is increas?ing due to the related ecological and public health risks. There is evidence that microcystins have a tumor promoting activity and microcystin-LRcould be tumor initiator and possibly cancerogenic to humans. Epidemiological studies have suggested that there is connection between primary liver cancer (PLC) and microcystins, as one of risk factor for high incidence rate of PLC in Serbia.

Astrobiology studies the origin, evolution, distribution and future of life in the universe. The most promising worlds in Solar system, beyond Earth, which may harbor life are Mars and Jovian moon Europa. Extremophiles are organisms that thrive on the edge of temperature, hypersalinity, pH extremes, pressure, dryness and so on. In this paper, some extremophile cyanobacteria have been discussed as possible life forms in a scale of astrobiology. Samples were taken from solenetz and solonchak types of soil from the Vojvodina region. The main idea in this paper lies in the fact that high percentage of salt found in solonchak and solonetz gives the possibility of comparison these types of soil with 'soil' on Mars, which is also rich in salt.

Tree mortality is a key factor influencing forest functions and dynamics, but our understanding of the mechanisms leading to mortality and the associated changes in tree growth rates are still limited. We compiled a new pan-continental tree-ring width database from sites where both dead and living trees were sampled (2970 dead and 4224 living trees from 190 sites, including 36 species), and compared early and recent growth rates between trees that died and those that survived a given mortality event. We observed a decrease in radial growth before death in ca. 84% of the mortality events. The extent and duration of these reductions were highly variable (1–100 years in 96% of events) due to the complex interactions among study species and the source(s) of mortality. Strong and long-lasting declines were found for gymnosperms, shade- and drought-tolerant species, and trees that died from competition. Angiosperms and trees that died due to biotic attacks (especially bark-beetles) typically showed relatively small and short-term growth reductions. Our analysis did not highlight any universal trade-off between early growth and tree longevity within a species, although this result may also reflect high variability in sampling design among sites. The intersite and interspecific variability in growth patterns before mortality provides valuable information on the nature of the mortality process, which is consistent with our understanding of the physiological mechanisms leading to mortality. Abrupt changes in growth immediately before death can be associated with generalized hydraulic failure and/or bark-beetle attack, while long-term decrease in growth may be associated with a gradual decline in hydraulic performance coupled with depletion in carbon reserves. Our results imply that growth-based mortality algorithms may be a powerful tool for predicting gymnosperm mortality induced by chronic stress, but not necessarily so for angiosperms and in case of intense drought or bark-beetle outbreaks., GGI by the Spanish Ministry of Economy and Competitiveness (Project AGL2014-61175-JIN)., AMH by the Spanish Ministry of Science and Innovation (Projects CGL2007-60120 and CSD2008-0040) and by the Spanish Ministry of Education via a FPU Scholarship., JJC, JCLC, and GSB by the Spanish Ministry of Economy (Projects CGL2015-69186-C2-1-R, CGL2013-48843-C2-2-R, and CGL2012-32965) and the EU (Project FEDER 0087 TRANSHABITAT).

Due to their ability to endure extreme conditions, terrestrial cyanobacteria belong to a group of organisms known as "extremophiles". Research so far has shown that these organisms posses a great capacity for producing biologically active compounds (BAC). The antibacterial and antifungal activities of methanol extracts of 21 cyanobacterial strains belonging to Anabaena and Nostoc genera, previously isolated from different soil types and water resources in Serbia, were evaluated. In general, larger number of cyanobacterial strains showed antifungal activity. In contrast to Nostoc, Anabaena strains showed greater diversity of antibacterial activity (mean value of percentages of sensitive targeted bacterial strains 3% and 25.9% respectively). Larger number of targeted fungi was sensitive to cultural liquid extract (CL), while crude cell extract (CE) affected more bacterial strains. According to this investigation, the higher biological activity of terrestrial strains as representatives of extremophiles may present them as significant BAC producers. This kind of investigation creates very general view of cyanobacterial possibility to produce biologically active compounds but it points out the necessity of exploring terrestrial cyanobacterial extremophiles as potentially excellent sources of these substances and reveals the most prospective strains for further investigations.