Increased frequency and intensity of drought events consequently affect oak high forests with the process of further decline, compromised growth and questionable natural regeneration. To overcome ...such difficulties, new adaptive strategies are required. Coppicing, as the oldest way of forest management, might provide some solutions. In our study two contrasting management systems, sessile oak coppice and high forest, were compared at the initial stages of regeneration and forest development. The transpiration of young oak sprouts and seedlings was monitored using sap flow systems during the 2015 growing season. The study of transpiration also included leaf water potential measurements during three measurement campaigns with contrasting weather conditions. Coppice sprouts transpired significantly more than seedlings on the individual tree and stand level during the entire growing season 2015; particularly large differences were observed during drought conditions. Coppice sprouts experienced lower water limitations due to the voluminous and deeper root system as indicated by leaf water potential results. Presented results attribute young coppices as one of the promising adaptable forest management types with a better adaptive strategy at the extreme sites under water limiting conditions.
•Forest soil properties were measured along the geographical gradient of Carpathians.•Soil respiration spatial variability was driven by soil carbon and nitrogen content.•Soil water content drove ...differences in soil respiration between 2022 and 2023.•Canopy gaps did not affect soil respiration consistently.
Carpathian Mountain beech-fir forests are exposed to severe pressures related to climate change. Alterations in soil respiration, the main source of CO2 emissions from forest ecosystems into the atmosphere, could potentially impact the future carbon balance of these ecosystems. We performed soil CO2 efflux measurements along the whole Carpathian arc on eight selected locations during two separate campaigns in 2022 and 2023. The correlations between soil CO2 efflux and various climatic, micrometeorological, and soil conditions were evaluated as well as the impact of canopy gaps at each site.
Soil CO2 efflux varied between the two campaigns primarily due to fluctuations in soil water content, while differences among the sites were more influenced by soil carbon and nitrogen content. The presence of a canopy gap did not consistently affect soil CO2 efflux; in some sites, it was lower in the gap than under a closed canopy, while in others, the opposite trend was observed. In conclusion, soil CO2 efflux measured at eight sites was closely associated with soil properties rather than with climate or micrometeorological parameters. Therefore, the potential influence of climate on the input of new organic matter through forest productivity and species composition will play a significant role in the decomposition and storage of soil organic matter.
•Advance regeneration was studied after the 2014 ice storm and the 2017 windstorm.•Rapidly light-exposed stands and regularly managed mixed stands were compared.•Quantum yield was measured three ...years after each large-scale disturbance.•Increased light on damaged plots negatively affected fir and favoured deciduous trees.•Ice storm caused more damage and slower recovery than windstorm.
Physiological response to rapid light exposure due to canopy disintegration in young beech, fir, Norway spruce and sycamore trees was measured in three consecutive years after the severe ice storm in 2014 and after windthrow in 2017. Nitrogen amount (Ntot), maximum assimilation response to light (Amax) and quantum yield (Φ) were measured in three categories of different light intensities under closed canopy with indirect site factor (ISF) < 15%, at the forest edge (15% <ISF < 25%) and in the open (ISF > 25%). Tree responses with number of seedlings per hectare were compared between damaged and undamaged sites, with young trees gradually adapting to light conditions in the two years following the two disturbance events.
Nitrogen levels were in the optimal range for all species studied. Rapid exposure to elevated light reduced efficiency in fir and increased efficiency in beech and especially sycamore. No differences in response were observed in spruce. Assimilation efficiency, where both tree species were equal, shifted towards shade. Recovery was similar for all species studied after both disturbances: better after the windstorm, compared to the ice storm, indicating the severity of the event. Reductions in seedling numbers followed the pattern observed for physiological traits.
This volume should be interpreted as a manual of best practices for sustainable forest management deriving from the experience of the project LIFE09ENV/IT/000078 ManFor C.BD coordinated by the ...National Research Council through the Institute of Agro-environmental and Forest Biology (CNR-IBAF). The other Project partners are: the Council for Agricultural Research and Economics (CREA), the University of Molise (UNIMOL), the Slovenian Forestry Institute (SFI) and the regions of Veneto and Molise. In addition, the National Centre for Forest Biodiversity of Verona and the Regional Office to biodiversity of Castel di Sangro of the Italian National Forest Service (CFS), as well as the Slovenian Forest Service (SFS) collaborated to the project. This manual consists of several individual articles dealing with specific issues related to the project. These articles are conceptually organized into five categories that from the description of the project and of its activities arrive at providing operative indications for forestry operators.
UDK 630*114:630*242(497.4)
In three high karst forest complexes, same spatial design was applied to observe the effect of silvicultural treatment - the degree of mature stand removal on soil efflux. ...In every forest complex nine subplots were established during the time of experiment according to predominating tree species in growing stock of the mature canopy stand - silver fir, Norway spruce and European beech. In 2012 silvicultural measures with different intensity - 50% and 100% removal of growing stock around the centre of the plot with minimal diameter of two tree heights were applied.
The seasonal pattern of CO2 efflux rates was mostly accountable by changes in soil temperature. Spatial heterogeneity in CO2 efflux rates was clearly reflected in management practice; release rates and recovery period were extreme in beech predominating sites, followed by the silver fir and norway spruce. It is our belief, that more oscillations may be expected in carbon release dynamics in the future, as the number of extreme weather events increases and the withdrawal of silver fir with its poor recruitment may have long-term consequences on these high karst high productive sites.
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 (Φ) 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.
•Beech, fir and spruce advance regeneration was studied after the ice-storm in 2014.•Rapidly light-exposed stands and regularly managed mixed stands were compared.•Assimilation responses to light ...were compared during 2015 and 2016 on four sites.•Increased light on damaged plots negatively influenced fir and favoured beech.•Spruce was not affected by the rapid light exposure.
A comparative study of young European beech, silver fir and Norway spruce in the Slovenian mixed forest stands was made at four locations, exposed to the rapid canopy disintegration after the severe ice storm in 2014. Nitrogen amount (Ntot), Leaf mass per area (LMA), maximal Assimilation response to light (Amax) and Quantum yield (Φ) were measured in three categories of different light intensities under closed canopy with Indirect Site Factor (ISF)<15%, at the forest edge (15%<ISF<25%) and in the open (ISF>25%). Tree responses were compared between damaged plots – rapidly exposed to light and undamaged sites, where young trees gradually adapted to the light environment during two years (2015 and 2016) after the disturbance event.
Nitrogen content of all three species was within optimal range values, highest in the open and lowest under canopy conditions on every plot. Rapid exposure to increased light levels affected most directly fir in the category of forest edge and under open canopies. Contrary to fir, beech responded in a favourable way, while no differences in response were evident in spruce. Assimilation efficiency, where both fir and beech were equal shifted towards the shade in both years.
European forests are becoming increasingly threatened by climate change and more frequent droughts. The likely responses of species to climate change will vary, affecting their competitiveness, their ...existence, and consequently, forest management decisions and measures. We determined the influence of climate on the radial growth of European beech and silver fir along the Carpathians to find similarities between the two species and the main differences. Along the Carpathian Mountains, seven sites with mature fir–beech stands above 800 m above sea level were selected and analyzed. Our study confirmed different responses depending on species and location. A more pronounced response of tree growth to climate was observed on the eastern side of the Carpathians, while it was less expressed or even absent on the southern sites. Both beech and fir show better radial growth with higher precipitation in July and slower growth with higher average and maximum temperatures in June of the current year. Fir demonstrates a positive correlation between radial growth and temperature in winter, while beech demonstrates a negative correlation between radial growth and temperature in summer. In the 1951–1960 decade, the average tree ring widths in fir and beech were largest at the southern sites compared to the other sites, but since 2011, the southern sites have had the lowest increase while northern sites have had the largest. Both species respond differently to climate and are likely to follow different competitive paths in the future.
•There was low CO2 efflux and moisture heterogeneity in the oak forest (22 and 13%).•Harvest increased heterogeneity of CO2 efflux, but had no effect on that of moisture.•Inter-plot heterogeneity of ...CO2 efflux was lower than that within plots.•Heterogeneity of CO2 efflux after harvest was affected by understorey vegetation.
Soil respiration is the second largest flux of carbon between terrestrial ecosystems and the atmosphere and it is substantially sensitive to climate change. Monitoring CO2 efflux and its upscaling from field measurements to the ecosystem level is a complex task, due to the high spatial and temporal variability of the fluxes. Human intervention, e.g. through forest harvest, may change both CO2 efflux and its spatial heterogeneity. The objective of our study was to quantify spatial heterogeneity of soil CO2 efflux within and among plots distributed within a topographically variable sessile oak forest stand before and after harvesting. Forest floor CO2 efflux, soil temperature and soil water content were measured monthly in a sessile oak forest during two growing seasons: one before and one after harvesting. Stand structure characteristics (gap fraction, leaf area index, tree number and size) and the amount of understory also were determined. Relationships between individual variables and spatial heterogeneity were analyzed. The small-scale spatial heterogeneity (expresses as the coefficient of variation) of forest floor CO2 efflux and soil water content (SWC) in the undisturbed forest was low, at maximum 0.22 and 0.13, respectively. Studied variables had no effect on spatial heterogeneity of forest floor CO2 efflux except for the amount of understorey vegetation which positively correlated with forest floor CO2 efflux. Although the studied forest was situated in topographically variable terrain, we observed that inter-plot heterogeneity of forest floor CO2 efflux was lower than that within plots. Stand harvest increased the intra-plot heterogeneity of forest floor CO2 efflux but did not affect the inter-plot heterogeneity. This leads to the conclusion that the number of positions within an individual plot should increase after harvest but the number of plots may remain unchanged to determine adequately ecosystem forest floor CO2 efflux.
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