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Clear-cut logging currently is a key factor transforming forest communities in many boreal regions. The dynamics of biogeochemical processes taking place in clear-cuts makes them a good model for studying the response of plants to changes in environmental conditions. This study aimed to assess the response of nutrient, carbon and water exchange parameters in coniferous and deciduous plants after clear-cut forest harvesting. The effects of environmental factors on the functional traits of regrowing trees in Scots pine (Pinus sylvestris L.), silver birch (Betula pendula Roth), aspen (Populus tremula L.) and grey alder (Alnus incana (L.) Moench) were analysed during four growing seasons (2016–2019) in a clear-cut site and under the canopy of an undisturbed bilberry-type pine forest in the middle taiga of Karelia, Northwest Russia. Unidirectional changes were observed in the specific nutrient content, specific leaf area, biological macronutrient absorption capacity, stomatal conductance, and rates of photosynthesis and transpiration in the different tree species along a gradient of environmental factors. In most cases, the nutrient concentrations and N:P:K ratio were consistent in all species as environmental conditions changed. Species-specific responses were observed for the N:P:K and K:Ca:Mg ratios, photosynthetic water use and nitrogen use efficiency. Contrasting environmental conditions in the clear-cut and under forest canopy most significantly affect plant capacity to absorb nitrogen. Variation in functional traits in the coniferous and deciduous species reflects their specific resource-use strategies in a heterogeneous environment and, hence, indicates the different adaptation potentials for various plant species.

Two and a half meters of sediments from Lake Heimtjonna in the Scandes Mountains reveal changes in the vegetation, climate, and sediment environment since deglaciation. The lake was deglaciated in the Late-Glacial (LG), perhaps as early as 16-18 ka cal BP. After deglaciation, the sediment environment at the Heimtjonna coring point was extraordinary and challenging to interpret. The genesis of the 1.7 m basal unsorted sediments including large stones is discussed concluding that the layer was rafted by lake-ice after the LG deglaciation. The Younger Dryas (YD) established a semi-perennial lake-ice that stopped the deposition of the ice-rafted stone-rich sediments. In the early Holocene, the unstratified and well-sorted clayey silt shows fluvial origin. In late Holocene, strong flood activity including the major flood disaster ‘Stor-Ofsen’ in AD 1789, caused a sediment hiatus at the coring point from ca 9.5 ka cal BP to ca 250 a cal BP. The LG interstadial warming initiated the succession from pioneer plants on mineral soils towards local dwarf-shrub heath. July temperatures reached at least 7–8 OC. In the LG and early Holocene, Papaver radicatum, Artemisia norvegica, and Campanula cf. uniflora today occurring at Dovre and with centric Scandinavian distributions, locally established. All have previously been connected to Weichselian survival on nunatak refugia. Continuous pollen curves of spruce (Picea abies) support the much-debated LG and early Holocene presence of spruce in the Scandes mountains. For the first time, it is shown that both grey alder (Alnus incana) and Armeria occurred in the Scandes in the LG and early Holocene. Due to dating errors, LG ages is exclusively based on stratigraphical correlations and considerations. The LG chronology must be thoroughly tested by future studies providing reliable AMS 14C-dates of terrestrial fossils.

Particleboards based on a mixture of grey alder (Alnus incana (L.) Moench) wood particles (sieve fraction 0.4-2 mm) and 15 or 25% of lignin powder obtained by hot pressing from four different industrial sources were investigated. Their density, thickness swelling, water absorption, modulus of rupture, modulus of elasticity in bending, and internal bond strength were determined. It was founded that the source and amount of the added lignin noticeably affected all tested properties of the particleboards.

Small inreases in CO2 stimulate nitrogen fixation and plant growth. Increasing soil N can inhibit nitrogen fixation. However, no studies to date have tested how nitrogen fixing plants perform under ancient CO2 levels (100 MYA), when nitrogen fixing plants evolved, with different levels of N additions. The aim of this study was to assess if ancient CO2, compared to present, favors nitrogen fixers over a range of soil nitrogen concentrations. Nitrogen fixers (Alnus incana ssp. rugosa, Alnus viridis ssp. crispa, and Alnus rubra) and their close non-nitrogen fixing relatives (Betula pumila, Betula papyrifera, Betula glandulosa) were grown at ancient (1600 ppm) or present (400 ppm) CO2 over a range of soil N levels, equivalent to 0, 10, 50, and 200 kg N ha−1 year−1. The growth of non-N fixing plants increased more than N fixing plants in response to the increasing N levels. When grown at an ancient CO2 level, the N level at which non-nitrogen fixing plant biomass exceeded nitrogen fixing plant biomass was twice as high (61 kg N ha−1 year−1) as the N level when plants were grown at the ambient CO2 level. Specific nodule activity was also reduced with an increasing level of soil N. Our results show there was a greater advantage in being a nitrogen fixer under ancient levels of CO2 compared with the present CO2 level.

Phenology provides intimate insights into ongoing changes in nature and seasonality with respect to humans. In this study, the most complete volunteer observer phenological data set for the territory of Latvia from 1970 to 2018 was evaluated. The data set includes observations of 159 phases of eight taxonomical groups, as well as abiotic phenomena such as the first snow, last spring frost, and agrarian activities. With reducing dimensionality, a hierarchical cluster analysis was used to group the 66 phenological phases of most observations into 7 clusters. The largest changes were observed in the early spring phenological phases of the pioneer species such as the start of flowering of Corylus avellana (hazel), Alnus incana (grey alder) and Populus tremula (aspen), noted as -8 days/decade. The trend of the spring emergence of insects and spring migratory birds also showed a negative tendency. The phenology of crops and agrarian activities has not changed significantly. The trends of the autumn phases were heterogeneous-leaf colouration and fall for some species (Populus tremula) and (Acer platanoides, Norway maple) was recorded on average later; for other species, there was a slightly earlier trend (Betula pendula, silver birch; Tilia cordata, linden). Earlier onset of the spring phases affects the changes in the length of the growing season (for Acer platanoides + 7.7 days/decade; Betula pendula + 3.3 days/decade). Since 1990, it has been common that many phases have begun sooner (particularly spring phases), whilst abiotic autumn phases have been characterised by late years. This study has shown that significant seasonal changes have taken place across the Latvian landscape due to climate change.

Aboveground dead wood has a range of important ecological functions, including carbon (C) storage. According to the Intergovernmental Panel on Climate Change guidelines for National Greenhouse Gas Inventories established on the basis of the United Nations Framework Convention on Climate Change and the Kyoto Protocol, Lithuania is encouraged to quantify C pools in forests, including C in living biomass, soil and dead wood. The aim of this study was to assess species-specific dead wood density (DWD) and carbon content (CC) per decay class for Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.), silver birch or downy birch (Betula pendula Roth or Betula pubescens Ehrh.), European aspen (Populus tremula L.), grey alder (Alnus incana (L.) Moench), black alder (Alnus glutinosa (L.) Gaertn.), common oak (Quercus robur L.) and European ash (Fraxinus excelsior L.), as the main representative hemiboreal forest tree species. The study findings revealed that mean DWD significantly decreased, while mean CC slightly increased during the wood decomposition process, which led to carbon density (CD) reduction over five decay classes. The mean CC showed little variation among the eight tree species and ranged between 47 and 54%. The lower CDs in the dead wood of decay classes 1 and 2 were more associated with coniferous than deciduous species. The estimated CD significantly decreased in all species with increasing decay class. Dead wood at decay class 5 of Scots pine, silver or downy birch, European ash and common oak had the highest CD, followed by Norway spruce and grey alder, and the lowest CDs were obtained for European aspen and black alder.

Following a review of the European distribution, habitat requirements and life history characteristics of two riparian tree species, Alnus incana (L.) Moench (grey alder, a member of the Betulaceae family) and Populus nigra L. (black poplar, a member of the Salicaceae family), we explore their changing spatial distribution and topographic position within a 7 km, island braided reach of the Tagliamento River, Italy, where Populus nigra dominates the woody vegetation cover. Combining field observations and information extracted from aerial images, airborne lidar data and river flow time series for the period 1986–2017, we investigate (a) the changing spatial distribution of all (P. nigra‐dominated) woody vegetation and of A. incana alone; (b) whether river bed topography can be associated with these changing spatial distributions and (c) we consider whether A. incana displays any particular characteristics in its spatial and topographic distribution that may indicate that it is complementing the physical engineering role of P. nigra. We show that A. incana predominantly grows in lines along channel, island and floodplain edges, bordering wooded areas dominated by P. nigra and that areas supporting A. incana are associated with the topographic development of the river bed. We conclude that A. incana appears to be acting as a complementary physical engineer to P. nigra, suggesting that similar complementary physical engineering of river beds may be achieved by species with different life history traits to influence landform development in other river environments.

Background Natural afforestation of former agricultural lands with alder species is common in Europe. Symbiotic nitrogen fixation by actinomycetes associated with alder species has been widely used for improvement of soil properties of abandoned agricultural lands, but relatively little is known of the interactions of these processes with soil type and chemical composition. We conducted a space-for time study with soil sampling under and outside grey alder tree canopies on two different soil groups to explore effects of colonisation of former agricultural lands by alder on soil properties. Results The results were analysed using analysis of variance. During the first 25 years after afforestation of former agricultural lands there was a significant increase in content of Ctot, Ntot, K+, Fe3+, Mn2+ and available P in the topsoil (0–10 cm and 11–20 cm) of Dystric Arenosols soils, which are deficient in organic matter. Such trends were not evident in organic matter rich Endostagnic Umbrisols soils, in which exchangeable K+ concentration decreased and exchangeable Fe3+ and Al3+ concentration increased. Conclusions The results show that the effects of grey alder on soil chemical properties depend on initial soil properties. The invasion of agricultural land by grey alder leads to spatial variability of soil chemical properties creating a mosaic pattern.

Annotation. The increase in the number of isolated antibiotic-resistant strains of microorganisms stimulates the search for alternative sources of biologically active substances that have antibiotic-potentiating action and are able to block the mechanisms of bacterial resistance to antibiotics. The aim of the study was to carry out bioautographic identification of the active components of gray alder fruits, geranium meadow rhizomes extracts and preparation “Altan” (extractant 90% aqueous-ethanolic), which showed synergism of antimicrobial action with erythromycin against skin isolates of staphylococci with different MLS phenotypes. Paper chromatography, thin-layer chromatography and bioautography were performed. Statistical processing of results: UTHSCSA ImageTool 2.0, Microsoft Office Excel 2011 On bioautograms of gray alder fruits extract and Altan with subinhibitory concentrations of erythromycin inoculated with S. epidermidis culture (inductive MLS-resistance phenotype), near the start line, areas with clear edges of growth inhibition were detected indicating the presence of hydrolysable tannins. Bioautograms of geranium meadow rhizomes extract showed the presence of compounds with antibiotic-potentiating activity with pronounced hydrophobic properties, indicating the presence of essential oils. In the extracts of gray alder fruits and geranium meadow rhizomes, the active components with antibiotic-potentiating properties, namely hydrolysable tannins and essential oils, have been identified. The fruits of gray alder and geranium meadow rhizomes are recommended for their preclinical and in-depth pharmacological study.

The invasion by emerald ash borer (Agrilus planipennis) of extensive black ash wetlands in the upper Great Lakes region of North America is expected to alter plant community structure and composition and, therefore, abiotic factors like temperature and hydrology. We conducted two experiments to examine how changes in leaf litter could alter ecosystem function via 1) changes in litter breakdown and 2) aquatic invertebrate feeding. For the first experiment, we placed litter bags containing black ash (Fraxinus nigra), swamp white oak (Quercus bicolor), and lake sedge (Carex lacustris), in either control or clear-cut black ash plots. We found that black ash litter broke down 2-3 times faster than other species and broke down faster in control plots than in clear-cuts. There was no effect of clear cutting on swamp white oak or lake sedge breakdown rates. For the second experiment, we fed shredding caddisfly larvae (Limnephilus indivisus) one of six species: black ash, swamp white oak, lake sedge, balsam poplar (Populus balsamifera), American elm (Ulmus americana), or speckled alder (Alnus incana) for 14 days. Caddisflies had the highest survival and greater resource use when given black ash or speckled alder, which are abundant in black ash wetlands. These results suggest that loss of black ash will alter ecosystem processes via changes in the physical environment, changes in leaf litter properties, and changes in shredder processing rates of leaf litter.

Arbuscular mycorrhizas (AMs) prevail in warm and dry climates and ectomycorrhizas (EMs) in cold and humid climates. We suggest that the fungal symbionts benefit their host plants especially in the corresponding conditions. The hypothesis tested was that AM plants are more drought-resistant than EM or nonmycorrhizal (NM) plants. Grey alder (Alnus incana (L.) Moench) seedlings were inoculated with two species of either AM or EM fungi or none. In one controlled-environment experiment, there was a watering and a drought treatment. Another set of seedlings were not watered until permanent wilting. The AM plants were somewhat smaller than EM and NM, and at the early stage of the drought treatment, the soil-moisture content was slightly higher in the AM pots. Shoot water potential was highest in the AM treatment during severe drought, while stomatal conductance and photosynthesis did not show a mycorrhizal effect. In the lethal-drought set, the AM plants maintained their leaves longer than EM and NM plants, and the AM seedlings survived longer than NM seedlings. Foliar phosphorus and sulfur concentrations remained higher in AM plants than EM or NM, but potassium, copper and iron increased in EM during drought. The root tannin concentration was lower in AM than EM and drought doubled it. Although the difference in drought resistance was not large, the hypothesis was supported by the better performance of AM plants during a severe short-term drought. Sustained phosphorus nutrition during drought in AM plants was a possible reason for this. Moreover, the higher foliar sulfur and lower metal-nutrient concentrations in AM may reflect differences in nutrient uptake or (re)translocation during drought, which merit further research. The much larger tannin concentrations in EM root systems than AM did not appear to protect the EM plants from drought. The differential tannin accumulation in AM and EM plants needs further attention.

Species-specific basic density (BD) data are necessary to improve the indirect methods of biomass determination. The density of tree components (e.g., bark, branches, roots) is studied much less than that of stem wood. Nevertheless, ignoring the specific BD values of these components in biomass calculations can lead to errors. The study aims to investigate BD variation of aboveground and belowground tree components by studying a total of 162 gray alder (Alnus incana (L.) Moench) and common alder (Alnus glutinosa (L.) Gaertn.) trees. From them, 55 stumps were excavated to determine the BD of the belowground components. Our findings reveal that the volume-weighted BD of the stem (wood and bark) and the branch density of common alder are higher compared to gray alder. Both species have similar bark density, while the BD of belowground components is higher for gray alder. The stem wood density of both species increases upward from the stump to the top. Compared to gray alders, the stems of common alders have more distinct radial within-stem density variation. According to our results, the application of default Alnus spp. wood density values recommended in the IPCC guidelines for the calculation of total biomass and carbon stock is likely causing overestimation. The BD values obtained in our study on alders’ biomass components will allow for more accurate appraisals of total biomass and carbon stock for gray and common alder forests.

The aim of this study was to investigate the effects of different plant parts and the age of plants at harvest as well as N2 fixing bacterial strains on the N concentration in symbiotic plant parts, especially on the δ15N signature of the actinorhizal plants and legumes. The 15N natural abundance method was used. Two actinorhizal plants were studied: Alnus incana (L.) infected with the Frankia strains ArI3 or “lsF” (local source of Frankia) and Hippophaë rhamnoides (L.) infected with the Frankia strains T1 or E15b. Two legume species were studied: Hedysarum coronarium (L.), infected with a soil suspension, and Robinia pseudoacacia (L.), infected with a crushed nodule suspension. It was particularly interesting that in A. incana, the two Frankia strains affected not only N concentration and δ15N signature of leaves and roots, but also had an impact on plant growth at first harvest. In Hippophaë rhamnoides plants inoculated with the Frankia strains T1 and E15b, N concentrations and δ15N values did not differ at any harvest time. However, plants nodulated by the Frankia strain T1 showed a higher nitrogen fixation rate and higher plant dry matter at all harvesting times. Based on our results for the quantification of N2 fixation with the “B” value, that is the δ15N value of the N2 fixing plants relying only on N2 fixation, plant parts, ages and strains should be carefully considered.

Desorption atmospheric pressure photoionization (DAPPI) is an ambient mass spectrometry (MS) technique that allows the analysis of both polar and nonpolar compounds directly from the surfaces of various sample types. Here, DAPPI was used to study the chemical profiles in different parts of birch and alder tree barks. Four distinct fractions of Betula pendula (silver birch) bark were collected from three different developmental stages of the stem, after which the chemical profiles of the different tissue types were measured. Of special interest were triterpenoids, a class of important defensive substances, which are found in the bark of the silver birch. Additionally, the chemical profiles of lenticels and the surrounding surfaces in the phellem of B. pendula (silver birch), Alnus glutinosa (black alder), and Alnus incana (gray alder) were screened with DAPPI. Another ambient MS technique, laser ablation atmospheric pressure photoionization (LAAPPI), was further used for the mass spectrometry imaging of lenticels on the B. pendula phellem. All the studied birch bark fractions showed individual chemical profiles in DAPPI. The mass spectra from the young apical stem and the transition zone resembled each other more than the mature stem. Instead, the phellem was found to contain a high amount of triterpenoids in all the developmental stages of the stem. The most intense peaks in the DAPPI mass spectra of the birch bark fractions were those of betulin and lupeol. Betulinic and betulonic acid peaks were intense as well, and these compounds were detected especially in the lenticels of the tree samples.

Soil contamination by metals is of particular interest, given that their retention times within the profile can be indefinite. Thus, phytostabilization can be viewed as a means of limiting metal toxicity in soils. Due to their ability to grow on contaminated soils, alders have repeatedly been used as key species in phytostabilization efforts. Alder ability to grow on contaminated sites stems, in part, from its association with microbial endophytes. This work emphasizes the fungal endophytes populations associated with Alnus incana ssp. rugosa and Alnus alnobetula ssp. crispa (previously A. viridis ssp. crispa) under a phytostabilization angle. Fungal endophytes were isolated from alder trees that were growing on or near disturbed environments; their tolerances to Cu, Ni, Zn, and As, and acidic pH (4.3, 3, and 2) were subsequently assessed. Cryptosporiopsis spp. and Rhizoscyphus spp. were identified as fungal endophytes of Alnus for the first time. When used as inoculants for alder, some isolates promoted plant growth, while others apparently presented antagonistic relationships with the host plant. This study reports the first step in finding the right fungal endophytic partners for two species of alder used in phytostabilization of metal-contaminated mining sites.

Grey Alder (Alnus incana (L.) Moench.) stands are distributed in the Carpathian area on alluvial deposits with sediments of different grain size as galleries along rivers and streams of the sub-montane to the middle montane level. The geological structure (Tertiary sedimentary deposits) in relation to the hydromorphological processes is the base for the structure of the stream valleys, which are in part very deep. Under the special microclimate of these deeper stream stretches with lower temperatures there are favourable conditions for the development of grey alder stands.

Grey alder (Alnus incana) is a highly productive indigenous tree species, potential for short-rotation forestry in the Baltic and Nordic countries. The aim of the study was to investigate t...

The regeneration and soil-mechanical reinforcement effect by the rooting system of grey alder (Alnus incana) were tested in an annually driven forest skid trail on a silty clay loam soil located in Southern Germany. One side of the skid trail was bordered by an eight-year-old alder plantation, on the other side, there were no trees. Soil physical properties (relative apparent gas diffusion coefficient (Ds/D0), bulk density and the coarse porosity) were measured in order to detect the effects on soil structure as well as on fine root densities, taken as a biological target variable. Values of soil physical parameters linked to the soil aeration status did not show significant differences between planted and unplanted wheel track; however, low values of bulk density measured on the laterally planted wheel track indicated significant improvements in the topsoil compared to the unplanted one. Also, values for fine root density were higher in these plots. Strong relationships between Ds/D0, bulk density and the coarse porosity with fine root densities were also found, which give evidence of their mutual effects, either amplifying each other or reciprocal. In the top soil, root density positively affects soil gas permeability, while in the deeper horizons fewer macropores are found, which are partially blocked by fine roots for gas exchange. In summary, the wheel track which is laterally planted with alder trees showed signs of an initial regeneration of soil structure as well as a reinforcement against further soil damage caused by annual wheeling.

In the study we have analysed the increment of fine-root biomass (FRBI) and the associated pool of carbon and nutrients (N, S, P, K, Ca, Mg, Na) under alder plantings (Alnus incana, A. glutinosa and A. viridis) growing on technosols developed from combustion wastes and extremely poor quaternary sands excavated by sand mining. The control sites were located in natural habitats in the Bieszczady Mountains within the natural range of the occurrence of the investigated alder species. The fine root biomass depended on the type and properties of the technosols substrate but did not differ between the alder species. The highest fine root biomass (>1000 g m−2) was found in the nutrient-poor sandy soils (SS) of a former sand pit, whereas technosols formed from combustion waste was

Background and aims The aim was to assess possible benefits or drawbacks of arbuscular-mycorrhizal (AM) and ectomycorrhizal (EM) colonisation compared to no mycorrhizas (NM) in seedlings of the same host species. Eight broadleaf species were tested for mycorrhiza formation. Grey alder (Alnus incana) and four fungal species were selected for further experiments. Methods Grey alder seedlings were inoculated with AM fungi Rhizophagus intraradices and Glomus hoi or EM fungi Paxillus involutus plus an ascomycete isolated from Alnus roots or mock-inoculated (NM). Results EM formed in 70% of root tips and AM in 30% of root length. AM plants were smaller than EM and NM, but their specific root length (SRL) and specific leaf area (SLA) were highest. Net photosynthesis, stomatal conductance and shoot water potential did not differ between treatments. Foliar Ca, K, Mg, Mn, N, P and S concentrations (mg g−1) were highest in AM plants. However, total foliar contents (mg per plant) were lowest in AM plants, except for P, K and Zn. Conclusions The larger SRL and SLA suggest more efficient resource usage in AM plants, even though these were smaller than EM and NM plants. Grey alder is proposed as a new model species for comparisons between mycorrhiza types in cold climates.

Inonotus obliquus grows in the Northern Hemisphere on some living broadleaved tree species as a pathogen, causing stem rot. In Estonia, the fungus is well known in the Betula species but can also be found on Alnus. Sterile conks of I. obliquus contain different bioactive compounds, but the quantitative and comparative research of these compounds in conks on different host species is limited. In the current work, I. obliquus was isolated and, evidently, determined from Alnus incana (L.) Moench., Alnus glutinosa (L.) Gaertn., and Betula pendula Roth, and the content of bioactive compounds in conks on these hosts were analysed. All the analysed conks sampled from A. incana and B. pendula contained betulin that varied from 111 to 159 µg/g. A significantly (p < 0.05) higher betulinic acid content was found in conks sampled from A. incana when compared with B. pendula: 474–635 and 20–132 µg/g, respectively. However, the conks from Betula were richer in total polyphenols, flavonols, and glucans. The content of inotodiol was quite similar in the conks from A. incana (7455–8961 µg/g) and B. pendula (7881–9057 µg/g). Also, no significant differences in the lanosterol content were found between the samples from these two tree species. To the best of our knowledge, this study is the first investigation of the chemical composition of I. obliquus parasitizing on Alnus. The results demonstrate that the bioactive compounds are promising in conks of I. obliquus growing not only on Betula but also on the Alnus species. It supports the opportunity to cultivate I. obliquus, also on the Alnus species, thus increasing the economic value of growing this tree species in forestry.

The emergence of microorganisms resistant strains is a natural biological response to the use of antimicrobial drugs that creates selective pressure, contributing to pathogens selection, survival and reproduction. The purpose of the investigation was to study the resistance development of staphylococci skin isolates to erythromycin and influence on it Alnus incana L. fruit extract subinhibitory concentrations. Development of resistance to erythromycin and influence on it Alnus incana L. fruit extract (extraction by 90% ethanol) subinhibitory concentrations were conducted with S epidermidis strains: sensitive and resistant to 14 and 15-membered macrolides. The study was carried out within 30 days by multiple consecutive passages of staphylococci test strains (concentration 1×107 CFU/ml) into test tubes containing broth and erythromycin ranging from 3 doubling dilutions above to doubling dilutions below the minimum inhibitory concentration. Statistical analysis of the results was carried out by one-and two-factor analysis of variance (ANOVA) and Microsoft Office Excel 2011. Rapid increase of resistance from 32 to 1024 μg/ml (F=34.2804; F> Fstand. max = 5.9874; p=0.0011) for S.epidermidis with a low level of resistance to 14 and 15-membered macrolides resistance to the erythromycine was observed. In the presence of Alnus incana L. fruit extract subinhibitory concentrations (¼ MIC), the initial MIC of erythromycin was decreased by 32 times to 1 μg/ml (F = 9.7497; F> Fstand. max = 5.9874; p = 0.0205). The sensitive strain after 30 passages did not develop resistance to erythromycin. Under the influence of erythromycin selective pressure, S.epidermidis strain with low initial level of MLS-resistance rapidly reaches a high-level resistance. Biologically active substances of the Alnus incana L. fruit extract significantly inhibit the resistance development in S. epidermidis to macrolides and eliminate it phenotypic features.

SUMMARY Pollen and macroscopic plant remains were studied at eight neighbouring sites, in order to define Late-glacial vegetational history in the northern French Alps. Local pollen assemblage zones are described and indicate that the main elements of vegetational history combine the features of adjacent regions. Herb pollen assemblages are similar to those recorded in the Swiss Late-glacial, whereas the early occurrence of shrubs and trees is typical of the southern French Alps. An early effect of altitude on vegetation distribution is demonstrated at the end of the Oldest Dryas. At that time the landscape consisted of a patchwork of Arteimisia–Chenopodiaceae steppe, with shrubs in hollows and valleys. Betula was recorded up lo 700 in and Juniperus up to 1300 m. This altitudinal variation became more pronounced with the arrival of new species. During the Allerod, mixed stands of Betula and Pinus were present up to an altitude of about 1000–1300 m, with Betula reaching 1700 m, this limit depending on factors such as exposure and continentality. The Younger Dryas oscillation is clearly recorded, as at more oceanic N.W. European coastal margins. Nevertheless, the record of the vegetation response to climatic change depends on the elevation of the studied sites. The limit of Pinus stands fell to 700–1000 m. At a lower altitude the climatic signal is weaker and alders [Alnus glutinosa (L.) Gaertn, Alnus incana (L.) Moench] began to spread. Continuous occurrences of alder owing to regional pollen transport are detected up to the highest sites. The empirical limit of Alnus is therefore proposed as a biostratigraphic marker of the Younger Dryas in the area. Finally. The possibility of a climatic deterioration that started during the late Allerod is discussed on the basis of absolute chronology.

summary The Holocene history of the forest-alpine tundra ecotone in Central Sweden (Scandes Mountains) is inferred from radiocarbon analyses of subfossil wood remains. Pinus sylvestris was the dominant subalpine tree species during the early Holocene, when it ascended almost 200 m higher than currently. A short climatic episode (less than 100 years) is postulated to have triggered erosional processes around 6300 n.p., and extinguished the upper part of the subalpine pine woodland. Subsequently, a subalpine belt of Betula pubescens ssp. tortuosa and Alnus incana developed. A Holocene thermal optimum occurred around 6100 b.p., when the birch/alder belt nourished and the tree-limits probably reached their highest levels during the Holocene. Shortly after 6000 b.p., a long-term pine forest retrogression started and the birch/alder belt was disrupted by expanding snow-beds. Pine receded slightly at its tree-limit, but the uppermost belt of closed pine forest (presently dominated by birch) remained intact until c. 3300 b.p., when a severe climatic deterioration occurred. The present-day subalpine belt of pure birch forest developed successively and increased in vertical extent after c. 5300 b.p., when summer temperature declined. The evolution of the birch belt is postulated to have been ultimately a response to decreased seasonally, which favoured birch at the expense of pine. Because of the ‘inertia’ characterizing the highest pine forest, the birch belt was relatively narrow until a major thermal decline e. 3300 b.p., when it made a massive downslope expansion. The latest phase of pine recession was during the Little Ice Age, 800–300 b.p.

summary We studied the effects of macronutrients on the production and distribution of fungal biomass and plant biomass in ectomycorrhizal (Paxillus involutus (Fr.) Fr.) or non-mycorrhiza] Pinus sylvestris L, and Alnus incana (L.) Moench. Fungal biomass was measured as ergosterol content in roots and extramatrical mycelium, Alnus infants was nodulated with Frankia. All six macronutrients were varied according to a two-level fractional factorial design, The plants were grown in pots during two growing periods in a growth chamber. Levels of N, P and sometimes K and interactions between them, had highly significant effects, whereas Ca. Mg and S had no significant effects. The production of extramatrical mycelial biomass peaked when P was low and other nutrients were high. This investment in extramatrical mycelium resulted in a 660%, higher biomass in mycorrhizal compared with non-mycorrhizal P. sylvestris at this nutrient regime. The proportion of fungal biomass in roots was stable in P. sylvestris hut more variable in A. incana. Alnus incana grew less when mycorrhizal then when non-mycorrhizal. The growth responses to mycorrhiza and to the different nutrient treatments were evident at the end of the first growing period. Non-mycorrhizal P. sylvestris did not respond to P limitation by a production of proportionally more roots. This might be a reflection of an obligate dependency on mycorrhiza for effective P uptake. By contrast, the root/shoot ratio in both mycorrhizal and non-mycorrhiza] P. sylvestris decreased strongly in response to increased N. The opposite root/shoot response was found in Alnus incana, and the ratio decreased strongly in response to increased P and increased in response to increased N.

The aims of this study were to evaluate the effect of macronutrients on nitrogen fixation in mycorrhizal and non-mycorrhizal grey alder (Alnus incana (L.) Moench), and to evaluate the effect of ectomycorrhizal mycelium on the transfer of symbolically fixed nitrogen from grey alder to Scots pine (Pinus sylvestris L). One alder and one pine were grown together in pots with root systems separated by a 20μm mesh nylon filter which allowed hyphae but not roots to penetrate. Half the plants of both species were inoculated with Paxillus involutus (Ft.) Ft. and all alders were inoculated with Frankia. Nutrient solutions were added with macronutrient (N, K, P, Ca, Mg and S) concentrations varied according to a two-level fractional factorial design. The plants were harvested after two growing periods in a growth chamber. Nitrogen fixation by alder and transfer of symbiotically fixed N from alder to pine was measured by

Many studies have found that future predicted CO2 levels can increase plant mass but dilute N content in leaves, impacting antiherbivore compounds. Nitrogen-fixing plants may balance their leaf C:N ratio under elevated CO2, counteracting this dilution effect. However, we know little of how plants respond to herbivores at the higher CO2 levels that occurred when nitrogen-fixing plants first evolved. We grew Alnus incana ssp. rugosa was grown at 400, 800, or 1600 ppm CO2 in soil collected from the field, inoculated with Frankia and exposed to herbivores (Orgyia leucostigma). Elevated CO2 increased nodulated plant biomass and stimulated the nitrogen fixation rate in the early growth stage. However, nitrogen-fixing plants were not able to balance their C:N ratio under elevated CO2 after growing for 19 weeks. When plants were grown at 400 and 1600 ppm CO2, herbivores preferred to feed on leaves of nodulated plants. At 800 ppm CO2, nodulated plants accumulated more total phenolic compounds in response to herbivore damage than plants in the non-Frankia and non-herbivore treatments. Our results suggest that plant leaf defence, not leaf nutritional content, is the dominant driver of herbivory and nitrogen-fixing plants have limited ability to balance C:N ratios at elevated CO2 in natural soil.

Rod Alnus Mill. (jove), sa više od 30 vrsta, pripada familiji Betulaceae. Alnus vrste koje rastu u Srbiji su: A.glutinosa (crna jova), A.viridis (zelena jova) i A.incana (siva jova). Jedinjenja izolovana iz jova poseduju širok spektar bioloških aktivnosti, a najvažnije su: citotoksična, antitumorska, antivirusna, antimikrobna i antiparazitska. Vrste roda Alnus su bogat izvor diarilheptanoida. Oni se u biljci prvenstveno nalaze u kori i lišću, kao prosti, glikozidi ili složeni – diarilheptanoid glikozidi esterifikovani različitim fenolnim kiselinama, najčešće cinamičnim. Biljke ovog roda su u tradicionalnoj medicini korišćene u brojne svrhe kao alterativi, purgativi, emetici, hemostatici, za lečenje raznih bolesti, uključujući i tumor. Cilj ovog rada bilo je izolovanje i određivanje strukturnih izomera alnuzida A i alnuzida B iz kore sive jove.

Melampsoridium hiratsukanum is an alien rust fungus which has spread pervasively throughout several European countries following introduction into North Europe at the end of the 20th century. The authenticity of several records of the Melampsoridium species infecting alder (Alnus spp.) in the northern hemisphere is questionable, due to the misidentification and confusion that surround many of the older reports. Given this complicated taxonomic history, and since a M. hiratsukanum-like rust is strongly impacting Alnus incana stands in the Alps, probably affecting the bank protection role of this species along rivers, the unambiguous identification of this pathogen was a pressing epidemiological and ecological issue. In this study, field surveys, light (LM) and scanning electron microscopy (SEM), and molecular characterization were put together in an attempt to solve the conundrum. Field monitoring data, LM and SEM analyses of key taxonomic traits (length of ostiolar cells of uredinium, uredinio-spore shape and size, spore echinulation, number and position of germ pores) and ITS-rDNA sequence-based identification, convergently and unambiguously connected the rust that is causing the current epidemic to the non-native M. hiratsukanum. We documented the completion of the M. hiratsukanum life cycle on its two taxonomically unrelated broadleaf/conifer hosts. This is the first report of M. hiratsukanum from naturally infected Larix decidua in Europe.

This study aims to derive individual tree allometric equations for the above- and belowground biomass components of grey and common alder based on data sets obtained in Latvia. The species aboveground biomass data consisted of 81 trees collected in 27 forest stands. The belowground biomass data were obtained from 27 common alder and 28 grey alder trees sampled throughout Latvia. For grey and common alder, the root-to-shoot ratio decreased with increasing tree dimensions. Our analysis revealed that biomass functions currently used in the national forest inventory overestimate grey alder and underestimate common alder biomass stocks in Latvia. Our findings indicate that the existing local aboveground biomass equation has an overall satisfactory predictive ability compared to the derived equations in this study. The equations from southern Sweden underestimate biomass for mature trees and overestimate small tree biomass, suggesting that even in the hemiboreal region, the grey and common alder populations could have a different distribution of biomass allocated to various components. Model examinations indicated that the derived allometric functions for grey and common alder were unbiased and performed well within the data range and are the best available to substantially improve national estimates of carbon sequestration and biomass resources in Latvia.

Very few studies have been made on the Black Woodpecker’s Dryocopus martius feeding on deciduous trees in Scandinavia, especially at winter. This pilot study on the Black Woodpecker’s feeding in grey alder Alnus incana showed that the grey alder is a significant feeding tree during the winter months. The woodpeckers seem to prefer feeding in the southerly sector of grey alder trunks with a diameter of 13.5–15.4 centimetres, in their first dying stages. This study indicates that litter of a significant size, that is found beneath trees penetrated by woodpeckers, are from carvings made by the Black Woodpecker. Litter surveying may hence be an alternative investigational method to radio tracking for nutritional studies on the Black Woodpecker. This paper also discusses the role of a potential prey found in grey alders, the alder wood-wasp Xiphydria camelus, as a complementary food source at winter in different parts of Sweden, compared to the more well-described carpenter ants Camponotus herculeanus found in Norway spruce Picea abies.

Bark beetles belonging to the genus Dryocoetes (Coleoptera, Curculionidae, Scolytinae) are known vectors of fungi, such as the pathogenic species Grosmannia dryocoetidis involved in alpine fir (Abies lasiocarpa) mortality. Associations between hardwood-infesting Dryocoetes species and fungi in Europe have received very little research attention. Ectosymbiotic fungi residing in Ceratocystiopsis and Leptographium (Ophiostomatales, Sordariomycetes, Ascomycota) were commonly detected in previous surveys of the Dryocoetes alni-associated mycobiome in Poland. The aim of this study was to accurately identify these isolates and to provide descriptions of the new species. The identification was conducted based on morphology and DNA sequence data for six loci (ITS1-5.8S, ITS2-28S, ACT, CAL, TUB2, and TEF1-α). This revealed two new species, described here as Ceratocystiopsis synnematasp. nov. and Leptographium alneumsp. nov. The host trees for the new species included Alnus incana and Populus tremula. Ceratocystiopsis synnemata can be distinguished from its closely related species, C. pallidobrunnea, based on conidia morphology and conidiophores that aggregate in loosely arranged synnemata. Leptographium alneum is closely related to Grosmannia crassivaginata and differs from this species in having a larger ascomatal neck, and the presence of larger club-shaped cells.

Mining activities create nutrient-poor sites that can be impacted by heavy metal solubilization. The introduction of plants into these environments can lead to organic matter deposition that can bind metals and limit their migration in the environment. This study aimed to determine which of four pioneer plant species (Alnus alnobetula ssp. crispa, Alnus incana ssp. rugosa, Larix laricina and Picea glauca) could survive and grow on undisturbed acidogenic gold mine tailings in Northwestern Quebec. After three growing seasons, all four outplanted species successfully established on the tailings without the use of organic amendments. Spruce and larch showed lower growth than the two species of alders, which had high survival rates and aerial biomass production per plot. None of the studied species had high metal translocation rates into leaf tissue despite high metal concentrations in the tailings. This study demonstrates the importance of preliminary field trials to optimize plant biomass and biodiversity on reclamation sites and to mitigate the risk of heavy metal translocation into plant tissues. Our results suggest that the reclamation of acidogenic tailings, without the use of capping materials, warrants further study.

The chapter summarises the research data on cultivating forest crops in abandonedand marginal farmlands (AL). The course of growth and productivity ofdifferent tree species in the local climatic conditions is clarified in a variety ofagricultural soils. The research results show the most appropriate tree species forshort-rotation or special end-use monoculture or mixed plantations, using Scotspine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.), silver birch (Betulapendula Roth.), pedunculate oak (Quercus robur L.), grey alder (Alnus incana (L.)Moench), alder (Alnus glutinosa (L.) Gaertn.), wild cherry (Cerasus avium (L.) Moench syn. Prunus avium), aspen (Populus tremula L.), hybrid aspen (Populustremula x tremuloides), and small-leaved lime (Tilia cordata Mill.). At the same time,research results show sustainability of management of plantation forests—positiveimpact on soil agrochemical properties, proportionate changes on above-groundvegetation, and improvement of economic benefits of farmlands

Investigations carried out in recent years have provided new data on the localities of some rare hypogeous fungi in Central Europe. In this study, we present new localities of Leucangium carthusianum, Melanogaster luteus, and Rhizopogon melanogastroides, two of which are new for Poland. Sporocarps of L. carthusianum were found in seven new localities in mixed and coniferous forests in the Western Carpathians as well as in Sudetes. In Poland, the species was also recorded in a mixed forest in the Kraków-Częstochowa Upland. Fir, Abies alba, accompanied the fungus in almost all known localities. Three localities of M. luteus were found in the Polish Western and Eastern Carpathians in Alnus incana communities mostly associated with streams. Knowledge of the distribution of this species in Europe is incomplete due to the complicated taxonomic history; nevertheless, it is regarded as rare, despite its wide distribution. One new locality of R. melanogastroides recorded in the Tatra Mts, Western Carpathians, is the fourth known to date. This species is mostly associated with Pinus mugo in high mountain localities (the Alps, the Tatra Mts). In this study, detailed descriptions and illustrations of the macro- and micromorphological features of the species are provided.

Riparian vegetation survival and establishment in gravel‐bed rivers depends on the balance between vegetation growth and flood disturbance. We present four examples of vegetation and landform development in gaps (linear open spaces) between established islands and/or floodplain within a reach of the middle Tagliamento River, Italy. Gaps offer shelter to vegetation, supporting higher colonization success and different vegetation‐landform evolution pathways. Time sequences of aerial images track vegetation development over 30 years in the four gaps. In combination with the flood disturbance time series, we interpret vegetation dynamics and identify the fate of sexual and asexual reproduction strategies by observing vegetation expansion from lines of young plants and shrubs and from uprooted deposited trees and pioneer islands, respectively. Analysis of image sequences reveals common features across the four gaps that are generalized to extend a conceptual model of island development. Growing conditions, disturbance energy and time (window of opportunity) between major floods are the main controls on vegetation colonization. These vary among rivers, among reaches along the same river and locally, as in the investigated gaps, allowing different tree species with different life history traits (e.g., Populus nigra, Alnus incana) to engineer local river landforms in different and complementary ways. Although the conceptual model is inspired by observations on the Tagliamento River, consideration of species life history traits and the joint influences of growing conditions, disturbance energy and windows of opportunity provide a framework that may be applied to other temperate rivers where trees drive landform development.

The associations formed by Alnus incana (L.) Moench. in the south of Western Siberia are limited to the middle and lower reaches of the Irtysh river in the Tyumen region (Tobolsk district, Russia). The paper describes Alnetum pteridiosum, Alnetum urticosum, Alnetum еquisetosum, Alnetum coricosum, Alnetum coricoso – еquisetosum, Alnetum coricoso – oxalidosum, Alnetum curtico – еquisetosum, Alnetum еquisetoso – miliosum, Alnetum coricosa – stellariosum, Alnetum urtico – aegopodiosum, Alnetum urtico – stellariosum, Alnetum–cirsiosum, Alnetum cystopteriosum, Alnetum urtico – miliosum, Alnetum poо – urticosum, Alnetum chrysospleniosum, Alnetum corydaliosum, Alnetum impatieno - urticosum and Alnetum stellariosum associations. In these associations, more than a hundred of species of higher plants grow. The species composition analysis showed that they are mesothermal and hydrophilic, the shrub layer is not typical for them, and the grass cover of alder forests is not uniform in origin. During the formation of Alnetum association they interact with taiga, birch and linden forests through mutual exchange of species, and also experience anthropogenic influences, accompanied by the penetration of synanthropic species.

The River Danube rises in the Black Forest (Germany), crosses 19 European states during its journey: Albania, Austria, Bosnia-Herzegovina, Bulgaria, Croatia, Germany, Italy, Macedonia, Moldova, Montenegro, Poland, Czech Republic, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine and Hungary and pours into the Black Sea (Romania), after a journey from west to east of 2860 km. Its water catchment area covers an area of 805,000 km2 and is surrounded by mountain groups such as the Alps, the Tatra, the Carpathians and the Dinarids. His territory is characterized by a temperate macrobioclimate with the exception of a strip along the coasts of the Black Sea, which possesses steppe characteristics. Of particular importance is the azonal vegetation of the Danube. These vegetation corresponds mainly to forests of deciduous species, among them Salix alba, S. fragilis, Alnus incana, A. glutinosa, Pinus sylvestris, Populus alba, P. nigra, Ulmus minor, U. laevis, Prunus padus, Quercus robur, Q. pedunculiflora, Fraxinus excelsior, F. angustifolia, F. pallisae, Tilia cordata, T. tomentosa and Carpinus betulus, with many associations that follow upon each other longitudinally from the mountains to the plains and transversely, from the center of the watercourse to the external terraces.

We investigated the ability of birch (Betula pendula Roth. and B. pubescens Ehrh.) and grey alder (Alnus incana (L.) Moench) trees of different sizes to recover after cutting and artificial infection with a common decay fungus, Chondrostereum purpureum (Pers. Ex Fr.) Pouzar. In birch, resistance to C. purpureum was initially highest among stumps of 13 cm diameter but by the end of the experiment almost all stumps were dead, whereas in grey alder mortality happened more slowly than in birch and was the same across the size range of stumps. After two growing seasons when almost all the original stumps were dead due to fungal infection, alder root suckers developed around small alder stumps, showing a high level of compensation compared to birch. These results indicate that birch and alder have different strategies for survival after biocontrol treatment.

The decomposition of the leaf litter, fine roots (d

In the study, we have analysed the impact of lead (Pb), cadmium (Cd), chromium (Cr) and copper (Cu) on fine root biomass and the associated level of bioacumulation heavy metals in fine roots under alder plantings (Alnus incana, A. glutinosa and A. viridis) growing on technosols developed from combustion wastes and extremely poor quaternary sands excavated by sand mining. The control sites were located in natural habitats in the Bieszczady Mountains within the natural range of the occurrence of the investigated alder species. Results showed that the bioaccumulation index of heavy metals in the alder roots depended on technosol properties, in particular, pH and texture, and, to a lesser extent, on the total content of heavy metals in soil. Additionally, it was found that in some concentration ranges, Pb and Cr had a stimulating effect on the growth of fine roots.

The reliability of diarylheptanoids as chemotaxonomic markers at inter- and intraspecific levels has been investigated. Six diarylheptanoids were quantified in bark ethanol extracts of four Alnus spp. populations by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The populations described here as locus classicus Alnus glutinosa (I) and locus classicus Alnus incana (III) are clearly differentiated. Compared to population I, individuals in population III have higher extract yields and hirsutanonol-5-O-β-D-glucopyranoside content and lower contents of hirsutanonol, rubranoside A and oregonin. Individuals from neighboring populations of A. glutinosa (II) and A. incana (IV) share similar contents of hirsutanonol. All the studied populations exhibit a high intrapopulation variability of the selected diarylheptanoids; they have a heterogeneous chemotype and they partially overlap. The geographical proximity of populations II and IV increases their chemical similarity. Principal component analysis (PCA) clearly shows that the biggest dispersion of individuals lies within population IV. The reason for its heterogeneity might be its physical proximity to population II, i.e. the appearance of hybrids. Also, geometric morphometrics of leaves was performed as a screening criterion for spontaneous hybrids.

This study is a continuation of research on the role of sucrose in figured wood formation in temperate trees. Different concentrations of sucrose solutions were administered for 7 weeks to trunk tissues ofBetula pendulaRoth, Alnus incana(L.) Moench andPopulus tremulaL. Then xylem anatomy was examined with particular emphasis to the number of vessels and the spatial orientation of xylem elements. InB. pendulaandA. incanaa high level of exogenous sucrose caused a reduction in the number and size of xylem vessels, even to the point of absence of vessels. Sucrose concentrations of 100 and 200 g l-1induced the formation of curly grain and anomalous club-shaped rays in xylem ofB. pendula.Populus tremulaxylem was not significantly altered by the experiment; the xylem anatomy was more seriously affected by wounding than by sucrose. InB. pendulaandA. incanathe wood formed during the experiment was similar to figured wood of these species. The decrease in the number and size of vessels in the xylem formed during the experiment possibly suggests that high concentrations of sucrose lead to a decline in the level of physiologically active auxin. Changes in the orientation of xylem elements points to a disruption of basipetal auxin transport. Further biochemical and physiological studies are needed to provide more comprehensive understanding of the relationship between sucrose and auxin during the development of figure in wood.

Agelastica alni L. (Coleoptera: Chrysomelidae) is a common beetle pest of alder trees (Alnus incana L.) in forests and parks across Estonia. The supercooling ability and capacity to survive low temperature exposure changes temporally. Relatively high unimodal supercooling point (SCP) levels (with a mean value of -6 to -8°C) were characteristic of the beetles in September during their diapause induction period, in April when the beetles had terminated their diapause development and in May when they started to reproduce. During their deep diapause period the SCPs of beetles had a bimodal distribution. Some beetles decreased their SCPs to -14 to -19°C while others retained a high SCP value of -6 to -8°C. Most vulnerable to low temperature were overwintered active beetles in May; after 1 h exposure their LTemp50 (median lethal temperature) was -6.3°C. In September with the onset of diapause tolerance of beetles started to increase, LTemp50 = -7.7°C. Beetles were most cold tolerant during their deep diapause period with LTemp50 < -12.0°C. A. alni beetles use one of two different strategies for overwintering, some are freeze-tolerant while others are freeze-avoidant. The freeze-avoidant beetles with low SCP (-12 to -15°C) acquired greater cold tolerance than those with higher SCP (-6 to -8°C), with LTemp50 = -13.7°C and LTemp50 = -11°C, respectively.

Species of Alnus (alders) have become invaders in several parts of the world. Here we report the presence of three naturalized alien species: A. glutinosa, A. incana and A. rubra from several populations in nature reserves of northwestern Patagonia, an area of remarkably high biodiversity. Alnus glutinosa had been cited previously for Chile and southern Argentina, but A. incana and A. rubra are here reported for the first time. As we found morphological variation within and among the populations of these introduced species that makes their discrimination difficult, we used chloroplast (trnH-psbA) and nuclear ribosomal (ITS) DNA sequences to confirm their identifications from morphological characteristics. Results from nuclear and chloroplast sequence data confirm the morphological tentative identification of the three species and remark the utility of molecular information together with morphology for the detection of introduced species of taxonomically difficult groups. The invasive characteristics of these alien tree species are discussed in relation to the conservation of the nature reserves where they are found. Fil: Calviño, Carolina Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Edwards, Priscila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Fernández, Martina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Relva, Maria Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Ezcurra, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Combustion wastes are characterised by extremely low N contents. Therefore, introduction of nitrogen-fixing species at the first stage of their biological reclamation is required. This paper presents an assessment of the growth parameters of alders (Alnus sp.) 10 years after their introduction to a disposal site of lignite combustion waste in Central Poland. Black (Alnus glutinosa) and grey alders (Alnus incana) were planted directly in the combustion waste. The soil amendment included three variants: control with pure combustion waste, admixture of lignite culm and addition of acid sand. Both alder species displayed good growth parameters comparable to those of alders in natural habitats. However, black alder had better growth parameters, such as stand density index (SDI), diameter at breast height (DBH) and height (H) than grey alder. The lignite amendment exerted a positive effect on tree growth, reflected in a higher SDI and H, whereas the acid sand amendment did not affect any of the growth parameters of the studied alder species. Despite the good growth parameters, the measured N:P and N:K ratios in the alder leaves largely differed from the optimal values indicating insufficient P and K supply at the combustion waste disposal site. This may pose a threat to further development of the introduced tree plantings. The introduction of alders along with the lignite addition into the planting holes seems to be a successful method of combustion waste revegetation.

The afforestation of sites disturbed after coal mining has shown to be a favorite technique to restore all ecosystem functions. Leaf traits of trees used in restoration may substantially affect nutrient return decomposition rates in soil and thus, ecosystem development. The aim of the study was to compare seasonal changes between the individual tree species at two different sites focussing on seasonal changes of leaf biochemistry, elemental composition, and their role in nutrient return to the forest floor and nutrient cycling. Foliage and litterfall characteristics (specific leaf area (SLA), nutrients, phenolics, lignin, chlorophylls, and cellulose contents) were studied at two sites of the same age (25 years) with different tree species at post-mining sites at the Sokolov area around 50° 14′ 09 N and 12° 39′ 05 E (Czech Republic). The first two sites (unreclaimed) were left to spontaneous succession with a dominance of Betula pendula, Salix caprea, and Populus tremula. The second two sites (reclaimed) was land levelled and afforested by Alders (Alnus glutinosa, Alnus incana). The study showed that foliage quality and composition differed between individual tree species and between sites, especially in the contents of nitrogen (N), calcium (Ca), magnesium (Mg), potassium (K), and lignin concentration. Alder reclamation was most influenced by a symbiotic relationship with bacteria Frankia which support a high concentration of N in foliage and litterfall. However, the highest concentration of basic elements (Ca, Mg, K) was in foliage and litter of unreclaimed sites. A. incana had the highest content of lignin in foliage which increased steeply from August to September. Also, the content of lignin increased slightly in litterfall of unreclaimed sites during the vegetation season thought could have lead to slowing decomposition of litterfall and nutrient cycling in comparison to reclaimed sites.

In this study, the effect of veneer preparation process on surface roughness, wettability and adhesive bond formation between birch (Betula pendula Roth), black alder (Alnus glutinosa L.), grey alder (Alnus incana L.) and aspen (Populus tremula L.) were evaluated. It is commonly known that adhesive bond is as strong as its weakest link. However, the results of present study show, that bond strength is not always directly related to properties of weakest wood material used in bonding. The roughness (Ra) for the birch was (11.13 μm) followed by black alder (13.32 μm), grey alder (17.25 μm) and aspen (23.28 μm). The best wettability was achieved on aspen (0.3°), which was followed by grey alder (5.0°), black alder (10.7°) and birch (43.6°). The results show that bonding lower quality and density wood species with birch does not significantly decrease the bond quality as it could be expected. This study shows that the bonds between birch and low quality and density wood species were significantly stronger than bonds formed solely between these low quality and density wood species. These results also imply that in utilization of low quality wood species by veneer-based industry does not immediately require adapting and changing the current processing parameters according to lower quality wood properties, if they are used in combination with higher density and quality wood.

The preparation of self-binding lignocellulosic fibreboards has been investigated. Different high-density fibreboards (HDF) were hot-pressed based on a mixture of grey alder (Alnus incana L. Moench) wood chips processed by steam explosion auto-hydrolysis (SE) and 15% or 25% lignin content from three different industrial sources: softwood kraft lignin (SWKL), soda wheat straw lignin (SoWhStL) and hydrolysis wheat straw lignin (HWhStL). Density, thickness swelling (TS) after immersion in water for 24 h, modulus of rupture (MOR), modulus of elasticity (MOE) and strength of internal bond (IB) of the board samples were determined. The amount (15% or 25%) and moisture content (MC) (18±1% or 5±2%) of the added lignin affected all the tested properties of the HDF except for density. However, the kind of the added lignin affects the obtained fibreboard more significantly compared to the control sample made without an admixture of lignin. In some cases, the tested values were diminished to half. The tested properties of the HDF samples produced with SoWhStL or HWhStL are compatible with standard requirements for medium-density fibreboard (MDF) for general use under dry conditions (EN 622-5, MDF), however, it depends on the lignin amount and MC.