Search Results (53)

Temperate broadleaved forests support diverse arthropod communities, but canopy-dwelling insects in European lime (Tilia cordata Mill.) stands are still poorly known. We surveyed light-attracted canopy insects in six T. cordata Genetic Conservation Units and related protected stands across Lithuania. One modified, solar-powered UV light trap was installed in the canopy (10–15 m) at each site and operated twice per month from June to August in 2023 and 2024. We used diversity metrics, similarity indices, multiple regression, and non-metric multidimensional scaling (NMDS) together with PERMANOVA to examine the structure of insect communities and assess the influence of environmental factors. In total, 6031 individuals representing 295 insect species were recorded, with higher abundance, species richness and Shannon diversity in 2024 than in 2023. Across both years and all sites, Shannon H diversity index ranged from 3.21 to 3.92. Sørensen indices indicated moderate species similarity among sites and distinct species composition at the Ukmergė genetic reserve. The 20 most abundant taxa comprised over 60% of all individuals, and dominance structure changed markedly between years: Serica brunnea dominated in 2023 but was nearly absent in 2024. Regression revealed a significant positive effect of air temperature on insect abundance (about a 31% increase per 1 °C), while precipitation had no significant effect on insect abundance. NMDS and PERMANOVA showed strong spatial structuring, with sites explaining most of the variation, and weaker but significant temporal and site-by-year effects. Overall, insect diversity metrics showed non-significant correlations with T. cordata genetic diversity parameters. Results demonstrate that mature T. cordata forest stands are important reservoirs of canopy insect diversity and highlight pronounced spatial heterogeneity, interannual dynamics, and temperature sensitivity of canopy assemblages in Lithuanian forests. Full article

Gnathotrichus materiarius Fitch, 1858 is a North American ambrosia beetle that has progressively expanded its distribution across Europe during the twentieth and twenty-first centuries. The aim of this study was to assess its occurrence in Slovakia based on multi-year surveys conducted in the Záhorie region and to document its first national record. Monitoring was carried out in 2021 and 2025 in pine-dominated stands using traps baited with pheromone and kairomone attractants. No individuals were detected in 2021. In 2025, two adults of G. materiarius were captured at a single site during the first inspection of traps baited with a (+)-α-pinene and ethanol blend. A large volume of stored pine timber was present in close proximity to the capture site, providing suitable breeding material. The findings suggest a recent introduction or early stage of establishment in Slovakia. Although the species is regarded as a technical pest of coniferous wood, it does not colonize healthy trees and currently poses a limited risk to vital forest stands. Continued targeted monitoring is important to assess its further spread. Full article

Foreign exchange is a significant financial market that attracts investors and countries seeking profitable investments. Despite the numerous techniques available for exchange rate forecasting and trend analysis, there is still a need for an automated, intelligent model to understand patterns and predict future trends. The creation of such prediction models can provide assistance for investors, financial institutions, and policymakers in governments. To overcome these issues, the proposed study has developed a novel hybrid deep learning model that encompasses a Bidirectional Long Short-Term Memory, an additive attention approach, and a random forest regressor (for long-horizon historical data), attempting to provide a prediction model for the following year’s official exchange rates (LCU per USD). The random forest regressor models the nonlinear interaction of features and assists with generalization, the attention layer focuses on the most influential time steps, and the Bidirectional Long Short-Term Memory (Bi-LSTM) captures all historical data for exchange rate series and temporal dependencies (or dependencies of a sequence of historical data). The use of a time partition (1960–2018 training data + 2019–2023 validation data + 2024 testing data) to train and evaluate the model provides realistic forecasting and prevents temporal leakage. The global panel dataset for more than 250 and 60+ year countries and regions demonstrate that all of the proposed models are better than all classical machine learning models, stand-alone deep learning models, and naive persistence models. The hybrid model shows the most significant prediction error reduction with R² as 0.98, proving long-horizon currency forecasting is extremely robust. Full article

The impacts of global warming on species’ habitat suitability and consequent potential range shifts have attracted increasing scholarly attention. As keystone species in China’s climax communities, Quercus spp. are widely distributed across the country and play vital roles in ecological conservation, economic development, and recreational services. Current research primarily focuses on variations in biomass at regional/watershed scales or employs distribution modeling to predict population responses to climate change. This study investigates nationwide trends in stand volume of Quercus spp. across three elevation gradients, analyzing the impacts of forest age, origin, and temporal dynamics by integrating historical National Forest Inventory (NFI) datasets with meteorological records spanning 1948–2021. Our findings demonstrate a persistent warming trend throughout China from 1948 to 2021, exhibiting significant seasonal divergence in temperature variability patterns. The stand volume of Quercus spp. showed non-significant elevational variation (p > 0.05), but exhibited marked differences across temporal gradients and origins. Notably, natural forests demonstrated higher stand volume than plantations (p < 0.01). Moreover, significant interactive effects were observed among elevation, origin, and forest age (p < 0.05), particularly for natural Quercus spp. Their stand volume exhibited distinct age-dependent trajectories: (1) high-elevation stands (>3000 m) displayed a “decline-recovery” fluctuation during 41–80 years, (2) mid-elevation stands (500–3000 m) maintained steady increases, and (3) low-elevation stands (<500 m) followed parabolic patterns peaking at 61–80 years. Our work further validates differential migration patterns of Quercus spp. under global warming, providing novel mechanistic insights into their climate-responsive dynamics. Full article

Saninten (Castanopsis argentea (Blume) A.DC.) is a protected plant that grows in the Mount Gede Pangrango National Park (MGPNP) area in West Java. Its population is limited, and as a valuable biological resource, Castanopsis has traditionally been utilized by indigenous communities, particularly those residing in proximity to the forest. However, the expansion and development of tourism pose a potential threat to the ecosystems of C. argentea and other endemic plant species, as well as to the wildlife that depend on these habitats. Comprehensive data on biodiversity, species composition, forest structure, and carbon stock status are crucial for assessing the potential impact of future tourism development. Our investigation was conducted from November 2023 to March 2024 in a three-hectare utilization zone within the confines of the national park. The findings documented a total of 36 species across 23 distinct plant families, with the families Fagaceae, Moraceae, and Myrtaceae exhibiting the highest levels of dominance. The regeneration of stands at the study site predominantly comprised arboreal species with the most substantial carbon stocks, including C. acuminatissima (Blume) A.DC. (Riung anak), C. argentea (Saninten), and Litsea sp. (Huru). C. argentea supplies several functions within this ecosystem that are interconnected with other components. With aboveground carbon stocks reaching 560.47 tons C/ha, the forest demonstrates high sequestration potential, reinforcing the need to conserve mature stands for both biodiversity and climate benefits. Therefore, in the future, the conservation of C. argentea will benefit the maintenance of the ecosystem’s attractiveness without adversely affecting the social and cultural structures of the local population. Full article

Dog activities recognition, especially dog motion status recognition, is an active research area. Although several machine learning and deep learning approaches have been used for dog motion states recognition, the use of ensemble learning methods is rather missing, as well as a comparison with deep learning ones. This paper focuses on the use of deep learning neural networks and ensemble classifiers in recognizing dog motion states and their comparison. A dataset from the Kaggle database, which includes measures by accelerometer and gyroscope and concerns seven dog motion states (galloping, sitting, standing, trotting, walking, lying on chest, and sniffing), was used for our experiments. Gaussian Naive Bayes, Decision Tree, k-Nearest Neighbors (kNN), Random Forest, a Bagging Tree-Based Classifier, a Stacking Classifier, a Compound Stacking Model (CSM), a Convolutional Neural Network (CNN), a Recurrent Neural Network (RNN), and a Hybrid Cascading Model (HCM) were used in our experiments. Results showed a 1.78% superiority in accuracy (92.64% vs. 90.86%) of deep learning (RNN) vs. stacking (CSTAM) best classifier, but at the cost of larger complexity and training time for the deep learning classifier, which makes ensemble techniques still attractive. Finally, HCM gave the best result (96.82% accuracy). Full article

Vegetation phenology has attracted considerable attention as one of the most sensitive indicators of global climate change. Remote sensing has significantly expanded our understanding of the spatial divergences of vegetation phenology. However, the current understanding of the reasons behind spatial divergences of vegetation phenology is not yet complete, and there is an urgent need to unravel the landscape processes driving spatial divergences of vegetation phenology. In light of this, the present study focused on montane forests of the cold temperate zone as its study area, collecting datasets such as the MCD12Q2 land surface phenology product, climate, topography, and stand height and adopting regression analysis and geo-detector model to investigate the individual and interactive effects of variables such as temperature, precipitation, elevation, slope, aspect, and forest height on forest phenology. The results indicated that because of the complexity of topography, the impacts of temperature on forest phenology were nonlinear. With fluctuation of elevation, the development of forest occurred later at the base and ridges of mountain and earlier in the valley bottom lands and mid-upper slopes. Temperature and precipitation exhibited a bilaterally strong interactive effect with slope on forest greenup. Both forest greenup and dormancy occurred earlier on shady slopes and later on sunny slopes. There may also exist an interactive effect between forest height and topographic factors on the spatial divergences of forest phenology. Future research may need to focus on whether there is a trade-off or synergy between the macroclimatic regulatory function of topography and the microclimatic regulatory function of canopy structure. Full article

As European forests face increasing threats from climate change and disturbances, diversifying tree species can be a crucial strategy to safeguard their ecological functions and climate mitigation potential. European beech is a valuable tree species with a wide distribution across Central and Western Europe. While the current natural distribution of European beech does not extend to the Baltic states, climate change models indicate a potential northward range expansion. This suggests the possibility of introducing beech to Baltic forests as a proactive measure to enhance the future resilience of local forests to climate variability. Beech’s ability to adapt to changing climate conditions, coupled with its potential to enhance biodiversity and provide high-quality timber, makes it an attractive option for forest managers. However, successful establishment and growth of beech in the Baltic region will depend on various factors, including competition with native species, soil conditions, and microclimate. Beech stands in southwestern Lithuania and Latvia, originating from diverse European populations, demonstrate good adaptation. Despite fragmentation, they can serve as sources for beech expansion. However, assisted migration may be crucial to support natural regeneration and ensure the species’ long-term viability in the region. To fully assess the potential benefits and risks of beech introduction, further research is needed to understand its ecological interactions with local species and its response to specific site conditions. By carefully considering these factors, forest managers can develop effective strategies to promote beech’s establishment and growth, ultimately contributing to the resilience and sustainability of Baltic forests in the face of climate change. Full article

Soil erosion has become an increasingly serious issue, drawing global attention. As one of the countries facing severe soil erosion in the world, China confronts significant ecological challenges. Against this backdrop, the country places great emphasis on soil conservation efforts, considering them a crucial component of ecological civilization construction. This study focuses on the carbon sink benefits of comprehensive soil conservation management in the loess hilly region and sandy slopes, using the Xiaonanshan Mountain small watershed in Youyu County, Shanxi Province, as a typical case for in-depth analysis. In terms of research methodology, an integrated monitoring approach combining fundamental data, measured data, and remote sensing data was developed. A comprehensive survey of the Xiaonanshan Mountain small watershed was conducted to categorize plant carbon pools and soil carbon pools, establish baseline scenarios, and utilize methods such as inverse distance spatial interpolation, sample calculation, and feature extraction to estimate forest carbon storage across different years and determine changes in soil and vegetation carbon storage. Simultaneously, data collection and preprocessing were carried out, including the gathering of fundamental data, field data collection, and internal data preprocessing. On this basis, a vegetation carbon storage model was constructed, and an assessment of soil carbon pool storage was conducted. The research results indicate that from 2002 to 2024, the continuous implementation of various soil conservation measures over 22 years has led to a significant increase in carbon storage within the Xiaonanshan Mountain small watershed. The vegetation carbon density of the entire small watershed increased from 14.66 t C/ha to 27.02 t C/ha, and the soil carbon density rose from 28.92 t C/ha to 32.48 t C/ha. The net carbon sink amount was 18,422.20 t C (corresponding to 67,548.08 t CO₂e in terms of carbon dioxide equivalent). Populus simonii and Pinus sylvestris var. mongholica significantly contribute to the carbon sink; however, due to partial degradation of Populus simonii, its net carbon sink amount is less than that of Pinus sylvestris var. mongholica. Additionally, the carbon sink capacity of the small watershed exhibits spatial differences influenced by conservation measures, with high carbon density areas primarily concentrated within the range of Populus simonii, while low carbon density areas are mainly found in shrub zones. The increase in carbon storage within the small watershed is primarily attributed to the contributions of vegetation and soil carbon storage, indicating that comprehensive soil erosion management has a significant carbon accumulation effect; moreover, the annual growth rate of vegetation carbon storage exceeds that of soil carbon storage, with the proportion of soil carbon storage increasing year by year. Furthermore, the vegetation carbon sink, soil carbon sink, and total carbon sink of the small watershed were separately calculated. In terms of benefit analysis, the Xiaonanshan Mountain small watershed offers ecological benefits such as increased forest coverage, carbon fixation and oxygen release, and biodiversity conservation; from an economic perspective, the value of carbon trading is substantial, promoting soil conservation and rural revitalization, with the total value of timber reaching 7.6 million yuan, of which the value of standing timber constitutes the largest proportion; social benefits include the improvement of environmental landscapes, stimulation of ecological tourism, and attraction of investment, with the Xiaonanshan Mountain Ecological Park receiving numerous visitors and generating significant tourism revenue. This research provides a theoretical basis and data foundation for comprehensive soil conservation management in project areas or small watersheds within the loess hilly and sandy slope regions, offering technical and methodological support for other soil conservation carbon sink projects in the area. Full article

Wood from reforestation gains market value due to its sustainable and legal origin. Planted forests in Brazil play a crucial role in economic, social and environmental aspects, with Eucalyptus and Pinus dominating the timber sector. However, non-majority species, such as those of the Khaya genus, have attracted great commercial interest due to the quality of their wood, being seen as an alternative to Brazilian mahogany. This study aimed to evaluate the biomass production of Khaya spp. stands and the nutrient uptake impacts in different harvesting scenarios. The research area is in Reserva Natural Vale (RNV) in Sooretama, Espírito Santo state, Brazil. The study was conducted 9.5 years after the planting of the Khaya spp. monoculture at a spacing of five m × five m, and the base fertilization consisted of 150 g of yoorin thermophosphate and 15 g of FTE BR 12 per seedling. The seedlings were of seminal origin, coming from different regions of Brazil and corresponding to three species: Kkaya grandifoliola C.DC (Belém-PA), Khaya ivorensis A. Chev. (Linhares-ES) and Khaya senegalensis A. Juss. (Poranguatu-GO). K. senegalensis exhibited the highest percentage of bark, while K. ivorensis was found to have the highest percentage of leaves. The biomass of the stems and branches did not vary by species. The relative biomass proportions had the following order: branches > stems > bark > leaves. The stocks of Ca and Mg were higher for K. grandifoliola, exceeding those for K. senegalensis (22.1%) for Ca and for K. ivorensis (42.3%) for Mg. The lowest nutrient uptake occurred in the scenario in which only the stem was removed, with averages of 44.17, 10.43, 21.93, 52.59 and 9.97 kg ha⁻¹ for N, P, K, Ca and Mg, respectively. Compared to total biomass harvesting, this represents a reduction in export levels by 91.34% for N, 79.31% for P, 94.66% for K, 94.29% for Ca and 93.28% for Mg. The nutrient uptake assessment demonstrated that more conservative harvest scenarios resulted in lower nutrient losses, indicating the importance of forest management practices that prioritize soil and nutrient conservation. In summary, the findings of this study provide a solid basis for the sustainable management of Khaya spp., highlighting implications for productivity and nutrient dynamics on a small or medium scale. Full article

The silver fir (Abies alba Mill.) is among the most valuable conifers in Europe for ecological and economic reasons. Throughout the course of history, primarily in the 20th century, its share in stands has been declining due to ill-suited management practices, especially clear-cut management, air pollution (SO₂ and NO_X emissions), and wildlife-induced damage. This literature review compiles findings from 338 scientific papers. It describes futures for silver fir and its distribution, ecological requirements, threats and diseases, seed production and nurseries, and forest management practices with emphasis on ongoing climate change. Based on recent knowledge of fir ecology and population dynamics, small-scale shelterwood and selection management have been introduced in fir stands, which have also stabilized them. Fir is an essential species for maintaining high stability and biodiversity, especially on planosols and in waterlogged habitats. Owing to its shade tolerance and environmental plasticity, it can coexist very well with many tree species in mixtures, which can increase the productive potential of stands within the natural range in Europe. The average stand volume of mature fir stands ranges from 237–657 m³ ha⁻¹. For its successful natural regeneration, it is essential to reduce cloven-hoofed game and thus prevent bud browsing damage. The attractiveness of fir in terms of heavy browsing is the highest of all conifers (52% damage). On the other hand, fir is a species relatively resistant to bark stripping and the spread of secondary rot compared with Norway spruce (Picea abies [L.] Karst.). Under global climate change, fir is expected to shift to higher elevations with sufficient precipitation, while in the southern part of its natural range or at lower elevations, outside water-influenced habitats, it is likely to decline. Climate change is intricately linked to the heightened prevalence of forest pathogens with significant damage potential in Europe, necessitating careful consideration and strategic adaptation within management practices of fir forests. Full article

The Emerald ash borer (EAB), Agrilus planipennis Fairmaire, 1888 (Coleoptera: Buprestidae), an invasive phloem-boring beetle, was first detected in the Luhansk Region of Ukraine in 2019. Subsequently, it rapidly expanded its presence to encompass a significant portion of the Kharkiv region and the parks of Kyiv. Previous research has established that the climatic conditions in Luhansk and its neighboring regions are conducive to the EAB, and the absence of a host plant (Fraxinus sp.) does not act as a deterrent to the pest’s expansion in Ukraine. Recognizing the urgency of identifying infested trees, our current research aimed to identify the most attractive EAB forest subcompartments based on forest site conditions and stand structure. Utilizing the MaxEnt model, we achieved an average performance in predicting the potential distribution of the EAB (AUC = 0.842). The six most impactful variables, contributing to 88.2% of the model, include “age of trees, years”, “area of forest subcompartment, ha”, “mean height of trees, m”, “proportion of Fraxinus excelsior in the stand composition, %”, “hygrotope index (humidity level), point”, and “number of neighboring-non-forest subcompartments”. Most likely, EAB occurrence is expected in the driest forest site conditions; the well-lit and warmed-up parts of stands, in particular; small subcompartments surrounded by non-forest landscapes; and forest shelter belts near roads and fields. However, the data obtained can be considered preliminary. To enhance the accuracy of our forecasting, it may be imperative to consider data on road localization, along which the pest can spread passively, as well as dominant wind speed. Full article

Forest fires represent a natural element in the dynamics of forest ecosystems. This study investigated the impact of a large-scale forest fire in 2022 (ca. 1300 ha) on epigeic ground beetles (Coleoptera: Carabidae). The research was conducted in coniferous forests at six pairwise study sites: burnt and unburnt dead spruce from bark beetles, burnt and unburnt clear cut, and burnt and unburnt healthy sites. Each site was replicated in four plots, with two pitfall traps deployed within each plot. In total, 48 pitfall traps (6 × 4 × 2) were installed in April 2023. It was tested how individual sites affected the similarity of ground beetle communities, whether they contained similar life guilds, and how significantly large-scale fire affects the abundance of pyrophilous ground beetles. A total of 5952 individuals and 63 species were recorded. We observed a significant decline in abundance at clear-cut and dead spruce burnt sites (73% and 77.5%, respectively) compared to the unburnt sites. Conversely, abundance increased by 88% at the burnt healthy site compared to the unburnt healthy site. Additionally, significant differences in the number of species per trap and species richness diversity (q = 0, q = 1, q = 2) were found only between burnt and unburnt healthy sites. In general, the highest species richness in the comparison of all study sites was at unburnt clear-cut and burnt healthy sites. Communities of ground beetles responded considerably to the fire, differing significantly from unburnt sites, and demonstrating a high degree of similarity. The original healthy spruce stands had highly homogeneous communities. On the contrary, any disturbance (bark beetle calamity, clear-cut) resulted in an increase in the alpha, beta, and gamma diversities of the ground beetle communities. Burnt sites attracted pyrophilous species (Sericoda quadripunctata, Pterostichus quadrifoveolatus) at very low abundances, with the highest activity in the second half of the season. In conclusion, ground beetles demonstrated a strong short-term response to large-scale fire, forming specific communities. However, pyrophilous ground beetles were unable to occupy a large-scale fire area due to the initial low abundance. Understanding post-fire processes can provide important guidance for management in areas designated for biodiversity enhancement. Full article

Lithium–sulfur (Li-S) batteries are the most attractive candidates for next-generation large-scale energy storage because of their high theoretical energy density and the affordability of sulfur. However, most of the reported research primarily concentrates on low sulfur loading (below 2 mg_s cm⁻²) cathodes using binders and traditional collectors, thus undermining the expected energy density. Herein, a N, O co-doped carbon nanotube (N, O-CNT) decorated wood framework (WF), denoted as WF-CNT, was designed as a free-standing sulfur host, achieving high sulfur loading of 10 mg_s cm⁻². This unique cathode featured low tortuosity microchannels and a conductive framework, reducing the diffusion paths for both ions and electrons and accommodating the volume changes associated with sulfur. Moreover, the internal CNT forests effectively captured soluble lithium polysulfides (LiPSs) and catalyze their redox kinetic. Consequently, the S@WF-CNT-800 sample exhibited a high initial discharge capacity of 1438.2 mAh g⁻¹ at a high current density of 0.5 A g⁻¹. Furthermore, a reversible capacity of 404.5 mAh g⁻¹ was obtained after 500 cycles with sulfur loading of 5 mg_s cm⁻² at 0.5 A g⁻¹. This work may support the development of high sulfur loading cathodes utilizing cost-effective and sustainable biomass materials for Li-S batteries. Full article

Leaf glands are found in many Rhamnaceae species, the buckthorn family, and are frequently used in taxonomic studies of the group, especially because they are easily visible to the naked eye. Despite the many records and extensive use in the taxonomy of the family, few studies deal with the classification of these glands and their roles for the plant. Thus, this study aimed to unravel the type, functioning, and putative functions of the leaf glands of three Brazilian forest species: Colubrina glandulosa Perkins, Gouania polygama (Jacq.) Urb., and Rhamnidium elaeocarpum Reissek. Leaves were collected and processed for surface, anatomical, histochemical, and ultrastructural analyses. In addition, the presence of visitor animals was registered in the field. The leaf glands of C. glandulosa and G. polygama are defined as extrafloral structured nectaries due to their anatomical structure, interaction with ants, and the presence of reduced sugars and of a set of organelles in the secretory cells. The unusual mechanism of nectar release and exposure in an apical pore stands out in G. polygama. The glands of R. elaeocarpum are ducts or cavities that secrete phenolic oil resin. Their presence is an atypical condition in the family, although they are often confused with mucilage reservoirs, much more common in Rhamnaceae. The extrafloral nectary, secretory cavity, and duct are associated with plant protection against phytophages, either by attracting patrol ants or by making the organs deterrent. Our data, combined with other previously obtained data, attest to the great diversity of gland types found in Rhamnaceae species. Full article