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Enzymatic hydrolysis is an environmentally friendly technology to produce sugars from pretreated biomass. Here, we show that the new Il-11 Irpex lacteus strain can synthesize cellulases in a high quantity. The peptone and filter paper contained in the medium significantly enhanced activity of endo-1,4-ß-D-glucanases (app. 50 IU/mL) and total cellulases (app. 9 IU/mL), whereas the medium with peptone and sodium carboxymethyl cellulose stimulated activity of exo-1,4-ß-D-glucanases (33 IU/mL). The expression of cellulases reached its maximum within 96-144 hours, and the optimum pH is 3,7. Thermal treatment at 30 °C for 60 minutes activated endo-1,4-ß-D-glucanases and total cellulases, while exo-1,4-ß-D-glucanases activity was enhanced following 40 °C treatment. In total, the cellulases complex (300 IU/g) saccharified untreated cellulose by 38 % in 48 hours. Concentrate with filter paper activity 100 IU/g is the more balanced enzyme-substrate ratio (2 %), which allows prolonging the saccharification process that will have a positive effect on the cost of the final product. [ABSTRACT FROM AUTHOR]

Herbarium collections have proven to be irreplaceable information base in recent studies directed towards revealing shifts in plants phenology and morphology caused by climate change. We examined eight parameters of morphological traits in the perennial herb species Plantago lanceolata L. collected in the wild between 1905 and 2019 and stored at the KW-herbarium (Kyiv, Ukraine) to find out if there were changes in plants' organ sizes during the last 114 years. For this period, we also calculated 13 climatic parameters obtained from meteorological records from the State archive that gave us the opportunity to check if there are any relations between the climate change in Kyiv region and shifts in morphological parameters of plants. Our results have shown Plantago lanceolata leaf blades, petioles and spikes had become significantly longer with time, increasing 3.0 cm, 2.1 cm and 0.6 cm respectively. The Co-inertia analysis revealed that 34% of the morphological changes was attributed to climate change. The analysis also demonstrated that leaf length correlated more with raised temperatures when plants were in flower, while spike length depended on the temperatures during bud development. Received knowledge can be used to reveal rapid evolutionary processes of the Plantago species and predicting their further course for the construction of historical climate models based on the leaves traits. [ABSTRACT FROM AUTHOR]

Climate change has a significant impact on natural ecosystems, particularly on floodplain forests that are among the most transformed ecosystems in the world. The climate sensitivity of dominant species is likely to play a key role in determining the susceptibility of flooded forests to climate changes. Here, we use dendrochronological approaches and local climate records from 1880 to 2015 to assess the response in pedunculate oak (Quercus robur L.) trees growing in a floodplain of the Dnipro River near Kyiv to climatic variables. Correlation analysis reveals the strongest positive association of the Q. robur tree-ring width chronology with May-June precipitation, May-June temperature, and May self-calibrating Palmers drought severity indices (scPDSI). The moving-window correlation analysis points to positive association with the scPDSI after the 1950s, when local river regulation was implemented. The positive correlation with current March precipitation is the least expected change in the oak growth-to-climate relationship that occurred in the aftermath of human alterations in the local river and regional climate changes. This study discusses the probable ecological consequences and ecophysiological mechanisms of observable climate-to-growth relationships and their temporal stability. [ABSTRACT FROM AUTHOR]

This article describes an investigation into the seasonal variations of frequency, damping ratio and amplitude of swaying and vibration of Norway maple Acer platanoides L. The study was carried through a series of pull and release experiments in situ and on branches in the laboratory using an artificial air flow. It was found that foliated trees had a natural sway frequency that was on average 1.6±0.2 times greater than in the out-of-leaf state. In contrast, the damping ratio of maple increased by 1.5±0.3 times in the summer period. The stem swaying initiated vibrations, i.e. elastic wave, in the roots with frequencies in the range of 45-50 Hz. Laboratory tests showed that the vibration amplitude of branches depended linearly on leaf mass for an air flow velocity of 1.94 m/s. [ABSTRACT FROM AUTHOR]

Red wood ants are capable of active thermoregulation in the nest, which allows them to achieve a high number of workers and a dominant position in biocenoses. We investigated the features of the spring warm-up and the ability for active thermoregulation of the mounds of the ants Formica polyctena and F. rufa in the vicinity of Kyiv, Ukraine. We have proposed a model of thermoregulation of the mound, which takes into account the heat flow from the sun, heat exchange with air and soil, and endogenous heat generated by the antcolony. The calculation of the model for specific values showed that only F. polyctena mounds with a diameter of more than 0.9 m and F. rufa mounds with a diameter of more than 1.1 m are able to maintain a constant optimum temperature in the nest. Comparison of the calculated data with the measurement results onthe studied nests showed that the diameters of the majority of moundsexceededthe critical values for both speciesindicatingthe ability ofthermoregulation. The possibility of using the model to study the thermoregulation of moundsin different natural areas is discussed. [ABSTRACT FROM AUTHOR]

Studying four species of red wood ants (Formica rufa, F. polyctena, F. aquilonia, F. lugubris), we examined nest morphometrics (height and diameter of anthills), spatial parameters (location of anthills of different sizes relative to each other), and the number of trails per colony in three regions of Ukraine and Russia: Kyiv region (877 anthills), the Urals (274 anthills) and Cis-Baikal (72 anthills). We have established a relationship between the number of anthills in the nest complex and the maximum parameters of the average height and diameter, as well as the average number of trails. Under optimal conditions, the infrastructure of the forage area of red wood ants becomes more complex - an increase in the average number of trails. We have shown that the morphometric parameters of anthills differ significantly in four species of red wood ants. In addition, it was confirmed that single anthills are on average smaller than colonial ones and have, on average, fewer trails per anthill. There is a pronounced spatial aggregation between the anthills of red wood ants of the same species (F. rufa, F. polyctena, Kyiv population) of all size classes. [ABSTRACT FROM AUTHOR]

Robinia pseudoacacia is one of the most frequent non‐native species in Europe. It is a fast‐growing tree of high economic and cultural importance. On the other hand, it is an invasive species, causing changes in soil chemistry and light regime, and consequently altering the plant communities. Previously published models developed for the potential distribution of R. pseudoacacia concerned 2070, and were based mainly on data from Western and Central Europe; here we extended these findings and included additional data from Eastern Europe. To fill the gap in current knowledge of R. pseudoacacia distribution and improve the reliability of forecasts, we aimed to (i) determine the extent to which the outcome of range modeling will be affected by complementing R. pseudoacacia occurrence data with sites from Central, Southeastern, and Eastern Europe, (ii) identify and quantify the changes in the availability of climate niches for 2050 and 2070, and discuss their impacts on forest management and nature conservation. We showed that the majority of the range changes expected in 2070 will occur as early as 2050. In comparison to previous studies, we demonstrated a greater eastward shift of potential niches of this species and a greater decline of potential niches in Southern Europe. Consequently, future climatic conditions will likely favor the occurrence of R. pseudoacacia in Central and Northeastern Europe where this species is still absent or relatively rare. There, controlling the spread of R. pseudoacacia will require monitoring sources of invasion in the landscape and reducing the occurrence of this species. The expected effects of climate change will likely be observed 20 years earlier than previously forecasted. Hence we highlighted the urgent need for acceleration of policies aimed at climate change mitigation in Europe. Also, our results showed the need for using more complete distribution data to analyze potential niche models. [ABSTRACT FROM AUTHOR]

• Native and non-native pines react uniformly to drought. • Local site conditions diminished interspecific variation. • No evidence that alien pines are better adapted to climate change than native pines. Two European pine species, Pinus sylvestris and Pinus nigra , are experiencing dieback as a result of the increasing frequency and intensity of extreme climatic events. Recent species distribution models predicted shrinkage of ecological niches in the near future and shifted their habitat range towards the northeast. Consequently, P. sylvestris may contract its range and P. nigra may expand in Central Europe. To test whether native pine species have an advantage over introduced pine species in acclimation to a novel climate in Central Europe, we investigated the climate sensitivity and vitality of P. sylvestris, P. nigra and P. rigida. We sampled mature stands of each pine species at three sites in Central Europe, for which we determined climate–growth relationships: temporal stability of temperature and precipitation correlations with tree-ring width and resilience indices. Based on remote sensing data, we assessed differences in surface reflectance and photosynthetic activity obtained from the normalised difference vegetation index (NDVI). Our analyses revealed that the climate sensitivity and surface reflectance of pines are not due to their nativeness in Central Europe but better explained by local site conditions. The specificity and variability of drought events may determine both the homogeneous and diverse susceptibility of species to a negative water balance. Therefore, the character of future climatic extremes seems to be the key to understanding the acclimation of native and non-native pine species in Central Europe. Because our study do not provide evidence of the superiority of non-native pine species over P. sylvestris , and the potential impacts of introduced species on local habitats seem poorly understood in the face of climate change, we urge particular caution in introducing species with unrecognized invasive potential. [ABSTRACT FROM AUTHOR]

• We predicted how alien tree species in Europe will respond to climate change. • Conifers will contract, while deciduous trees will expand climatic niches. • Potential range shifts predicted for 2061–2080, will be observed in 2041–2060. • We provide a novel perspective for forest management and nature conservation. Alien tree species are considered both a threat to nature conservation and a base for forest management. We compiled species occurrences from biodiversity databases, forest inventories, and literature data. We modeled the availability of potential niches using the MaxEnt method and bioclimatic variables for current conditions, 2041–2060, and 2061–2080 periods. We used four climate scenarios: SSP126, SSP245, SSP370, and SSP485. The results confirm our hypotheses that, (i) coniferous species will contract, and deciduous trees will expand their climatic niche, (ii) a significant part of the areas where the studied species currently occur will be outside their climatic optimum in the coming decades; (iii) changes in the climatic optimum distribution will be greater in the 2041–2060 period than in 2061–2080. These predicted shifts are relevant for evidence-based management in sites already occupied by the studied alien trees. Our results are also relevant to the development of prevention and early detection measures in areas predicted to become climatically suitable for the studied species. [ABSTRACT FROM AUTHOR]