•Altered mixture and structure of Alpine mixed forests delays natural regeneration.•We studied optimal gap spatiotemporal dynamics for natural regeneration.•Results indicate gap and microsite ...partitioning between Norway spruce and beech.•Spruce seedlings were associated with diffuse light and thick organic horizons.•Higher topsoil moisture content, proximity of seed trees favoured beech seedlings.
Mixed mountain forests composed of Picea abies, Abies alba and Fagus sylvatica represent one of the most important alpine ecosystems with respect to economics, environmental effects and social functions. However, many stands are characterised by even-aged forest structure and altered tree species composition, making them more prone to disturbances and less effective in protection against natural hazards. Changes to the forest microclimate and nutrient cycling delay natural regeneration and favour the successional development of ground vegetation. In this study we hypothesized that the creation of gaps of appropriate size and shape would facilitate natural regeneration and forest conversion. In 2003, we selected 15 gaps, ranging in size from 0.01 to 0.62 ha and more than 50 years in age, and three areas below closed canopy on a south facing P. abies dominated mixed mountain forest (1380–1480 m a.s.l.). Within the gaps we established 542 systematically distributed research plots (1.5 × 1.5 m) and analysed regeneration attributes according to height classes, ground vegetation coverage, light climate, topsoil moisture, microsite relief and soil features. Measurements were repeated after five vegetation seasons and indicated minimal changes in vegetation structure and the slow development of regeneration overall. Vegetation ordination and generalized linear mixed models showed a positive association of P. abies seedling abundance with diffuse light, thickness of the organic horizons, presence of CWD and moss coverage and a negative association with ground vegetation cover, soil water content, Landolt indication value for nutrients and direct light. Fagus sylvatica seedlings were more abundant closer to seed trees, on less acidic soils with higher moisture content and on concave microrelief. The results indicate that P. abies and F. sylvatica seedlings may successfully establish under slightly open forest canopies, but in a few years the former require amounts of diffuse light comparable with that in the medium sized gaps in this study (0.15 ha). Due to the negative association between direct light and regeneration, gaps should be elliptical with the long axis oriented east-west. Recruitment of all species was significantly retarded by overbrowsing.
Remifentanil is an ultra-short-acting synthetic opioid-class analgesic which might be increasingly used “off-label” as pain management during labour. Side effects in parturients during labour, and in ...the infant at birth are of particular concern, especially respiratory depression which is concentration-dependent, and can occur at levels as low as 3–5 ng mL
. The safety of such use, particularly in newborns due to remifentanil placental transfer, has not been fully demonstrated yet, partly due to the lack of a suitable non-invasive analytical method. The aim of our work was to develop a sensitive method to monitor the levels of remifentanil in neonates by a non-invasive sampling of umbi lical cord blood to support efficacy and safety trials. The presented LC-MS method is sensitive enough to reliably quantify remifentanil in just 20 µL of blood at only 0.3 ng mL
. The dried blood spot sample preparation included solvent extraction with subsequent solid-phase extraction. The method was validated in terms of accuracy, precision, recovery, matrix effect, and stability, and was successfully applied to a small pilot study. The estimated arterial blood concentrations at the time of delivery ranged from 0.2 to 0.3, and up to 0.9 ng mL
in neonatal, and maternal samples, respectively.
•We studied regeneration dynamics in temperate forests disturbed by windthrows.•Higher seedling densities were at lower altitudes and on northerly exposed slopes.•Disturbed micro-sites, proximity of ...forest-edge favoured sapling survival.•Sapling survival was negatively associated with low sapling height and browsing.•Favouring of planted saplings decreased density of spontaneous regeneration.
We studied regeneration dynamics in forests disturbed by three different windthrow events in 2008 in Slovenia to assess the success of natural regeneration vs planting and subsequent silvicultural treatments. Fifty-three plots with planted saplings of Norway spruce and sycamore maple and 50 plots with dominant naturally regenerated saplings were selected in a randomly stratified manner. Sapling characteristics (height, height increment, root collar diameter, free-to-grow score, browsing and micro-site) were assessed in 2012 and 2014. Herbs and seedling establishment were studied in two subplots within each plot. Average seedling density was 13,074 and 14,674 ha−1 four and six years after the windthrows, respectively. Seedlings were irregularly distributed, which suggests micro-site differences in regeneration dynamics. The results indicated lower seedling success on sites that were southerly exposed, farther from the forest edge and seed trees, on undisturbed micro-sites and at higher altitudes. On such sites planting was justified. While seedling density indicated a positive relation to herb coverage, sapling survival was negatively associated with it as well as with browsing. Initial sapling height was the strongest predictor of survival. Spruce saplings had the lowest mortality, while shade-tolerant silver fir and beech experienced high mortality. The study indicated a high density and species diversity of naturally regenerated seedlings within windthrow areas, which was reduced by planting, mowing of competing vegetation and protection measures favouring planted saplings. Recommendations for the improvement of silvicultural operations for post windthrow restoration are given.
► We studied tree regeneration and vegetation in medium-sized gaps over a decade. ► Decrease in diffuse light (11.0–5.7%) indicated importance of several gap releases. ► Gap partitioning among herbs, ...beech and sycamore maple regeneration was observed. ► Beech advance regeneration under closed canopy was hindered by Allium ursinum. ► In similar conditions gap periphery seems advantageous for beech establishment.
Canopy gap recruitment in beech (Fagus sylvatica L.) old-growth forests is influenced by the interplay of the canopy gap disturbance regime, site factors, and stand history. Persistent seedling and sapling banks of beech and other shade tolerant species often play a major role in canopy gap closure. To gain more insight into interactions between medium-sized gaps and pre-gap ground vegetation patterns, we studied beech regeneration over a 10-year period on a site rich in wild garlic (Allium ursinum L.) in a Dinaric beech old-growth forest. In 1999 we selected the five largest newly created gaps (∼200m2) and systematically established 13 permanent plots (1×2m) in each gap. In 1999, 2004, and 2009, we sampled tree species regeneration (density, cover, and growth), ground vegetation (composition and cover), and light climate. Beech regeneration slowly increased in density and cover despite an overall decrease in light (11.0–5.7%). The same was not true for maple. While beech was present in all regeneration classes, dominant maple seedlings rarely reached 50cm. Beech also had a significantly greater height increment. Regeneration of both species was negatively affected by Allium cover, low light levels, and ungulate browsing. Gap partitioning was observed among shade tolerant Allium, which preferred microsites under closed canopy and low light levels, beech regeneration, which preferred gap periphery, and other less shade tolerant herbs, which favoured gap centres. The slow development of the regeneration indicated the importance of several gap releases. The high maple seedling density and less abundant beech advance regeneration in this study site compared to other beech sites suggests that Allium dominated managed forests might present an opportunity for growing less shade-tolerant species, if managed with a gap-oriented silvicultural system (e.g. irregular shelterwood).
•We examined successional trajectories in fenced and unfenced salvaged stands.•Spruce’s share in regeneration density decreased over time.•Fencing accelerated successional development and favoured ...broadleaves.•Regeneration niche partitioning was affected by meso-relief and forest edge.•Shorter distances to seed trees favoured spruce and anemochorous broadleaves.
Management of Norway spruce monocultures in Europe is becoming increasingly difficult due to frequent natural disturbances. Their transformation could be especially challenging if several disturbances interact. In 2003 a spruce bark beetle outbreak damaged large tracts of spruce bottomland successional forest in southeast Slovenia where overabundant ungulate populations are present. In openings (5.4–7.5ha in size) in four salvaged forest compartments, we studied the effects of meso-relief, forest edge, seed trees and fencing on vegetation succession and tree regeneration. In 2005 and 2013 we sampled seedling density on 240 plots according to height class and species. In the second inventory we also assessed distance to seed trees and on a subsample of the plots the coverage of vascular plants. The results indicated sufficient natural regeneration and niche partitioning among species groups, with Norway spruce seedlings being more successful at stand edges, pioneers and anemochorous broadleaves in gap centres, and zoochorous broadleaves on plateaus as opposed to sinkholes. Seedling density of all anemochorous broadleaves was higher closer to seed trees. Spruce seedling abundance was negatively associated with the cover of herbaceous vegetation and that of pioneer trees with shrubs. Fencing resulted in significantly greater density, height and coverage of seedlings as well as a higher share of broadleaves. While bark beetle outbreak triggered regeneration of broadleaves, overbrowsing acted in the opposite direction by facilitating spruce. Thus, to accelerate successional development and to prevent a spruce dominated alternative ecosystem state, a significant reduction in deer abundance is needed. To safeguard seed sources, promote seed dispersal by encouraging perches and shelters, and preserve potential habitats, some damaged trees should be retained during salvaging operations.
Period 2 (PER2) is an important factor in daily oscillations called circadian rhythms, which are emerging as one of the most important regulatory networks, responsible for homeostasis and ...transcriptional regulation of a number of genes. Our work shows that PER2 could act as a co-activator of the constitutive androstane receptor (CAR), a key nuclear receptor (NR) that regulates the metabolism of endobiotics and xenobiotics. Bioinformatic analysis shows that PER2 and CAR possess structural elements that could enable them to interact which was confirmed experimentally by CoIP experiment. Co-transfection of mouse hepatocarcinoma cells with plasmids overexpressing Per2 and Car increases expression of Bmal1, a potential CAR target gene, more than transfections with Car only. This is the first report indicating the interaction of PER2 and CAR.
Since the mid-19th century, Pinus nigra plantations have played a key role in the restoration of degraded European landscapes. Nowadays, these plantations are aging and prone to natural disturbances, ...insect infestations, and diseases. For their successful gradual conversion, knowledge of optimal gap spatiotemporal dynamics is crucial. We studied herb and natural regeneration patterns along with site factors on 477 subplots within 44 plots distributed over four stand types: closed stand (14% diffuse light), open stand (21%), gap edge (23%), and gap (57%). Despite the abundant Quercus petraea, Q. cerris, and Q. pubescens mast year, no one-year seedlings were recorded, which is likely due to the summer drought. Short seedlings (h < 20 cm) of Quercus sp., Fraxinus ornus and Ostrya carpinifolia were more successful within closed stands. Short Quercus seedlings were positively associated with soil depth and negatively associated with soil nutrients, distance to seed trees, and Sesleria autumnalis coverage. Taller Quercus seedlings required more light than both of its strongest competitors and were positively related to humid soils and less rocky sites. Ungulate overbrowsing significantly impeded natural regeneration. The results indicate a satisfactory Quercus density for conversion and the importance of advanced regeneration, which should be gradually, but persistently, released by progressively widening gaps.
Z dokumentom želimo smernice, ki jih predlaga GINA, vključiti v slovenski prostor. Želimo, da bi dokument služil enotnemu in dogovorjenemu pristopu k obravnavi bolnikov z astmo na primarni in ...specialistični pulmološki ravni.
The practice of salvage logging dead and damaged timber following large high severity disturbances has raised much controversy, partly because of the negative ecological effects that such practices ...have on forest ecosystems. Many of the studies on salvage logging effects, however, have been done on sites damaged by large, severe disturbances. Less is known about the ecological consequences of salvage logging following intermediate severity disturbances that cause partial canopy damage at smaller scales. We examined the response of the herbaceous layer and tree regeneration to salvaged and non-salvaged treatments following small-scale intermediate severity disturbances in eight mixed beech (Fagus sylvatica L.) dominated forest stands in Slovenia. The cover and diversity of herbaceous vegetation, as well as the density and diversity of tree regeneration were similar between treatments across the study sites. The only notable differences between the treatments were that salvaged sites had a larger proportion of shade intolerant tree species in the regeneration layer, while non-salvaged sites tended to have a more well-developed regeneration layer in taller height classes. The results suggest that salvage logging following small-scale intermediate severity disturbances may not hinder forest recovery in mixed beech dominated forests.
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