Search Results (435)

This study reconstructs seven decades (1949–2019) of morphodynamic changes and sediment dynamics in the Diable River (Québec, Canada) using nine series of aerial photographs, a high-resolution LiDAR Digital Elevation Model (2021), and grain-size analysis. The objectives were to document long-term river evolution, quantify erosion and deposition, and evaluate sediment connectivity between eroding sandy bluffs and depositional zones. Planform analysis and sediment budgets derived from DEMs of Difference (DoD) reveal an oscillatory trajectory characterized by alternating phases of sediment export and temporary stabilization, rather than a simple trend of degradation or aggradation. The most dynamic interval (1980–2001) was marked by widespread meander migration and the largest net export (−142.5 m³/km/year), whereas the 2001–2007 interval showed net storage (+70.8 m³/km/year) and short-term geomorphic recovery. More recent floods (2017, 2019; 20–50-year return periods) induced localized but persistent sediment loss, underlining the structuring role of extreme events. Grain-size results indicate partial connectivity: coarse fractions tend to remain in local depositional features, while finer sediments are preferentially exported downstream. These findings emphasize the geomorphic value of temporary sediment sinks (bars, beaches) and highlight the need for adaptive river management strategies that integrate sediment budgets and local knowledge into floodplain governance. Full article

Changes in vegetation type shape the soil microenvironment, thereby regulating the changes in the organic carbon pool by influencing microbial communities and the accumulation of microbial necromass carbon (MNC). This study investigated microbial biomass—via phospholipid fatty acids (PLFAs) analysis—and MNC accumulation across three cold–temperate forest types: Larix gmelinii forest (L), Larix gmelinii–Betula platyphylla Sukaczev mixed forest (LB), and Betula platyphylla Sukaczev forest (B). The results showed that the L had the lowest contents of pH, water content (WC), soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), and total phosphorus (TP), but the highest contents of dissolved organic carbon (DOC), available phosphorus (AP), and carbon to nitrogen ratio (C/N) (p < 0.05). LB had the lowest PLFAs content and the highest ratio of Gram-positive bacteria/Gram-negative bacteria (G+/G−), and total fungi/total bacteriai (F/B) of L was the highest. B had the highest alpha diversity index, and significantly positively correlated with pH, SOC, TN, AN, and TP. TP and C/N were the primary elements for significant differences in microbial community structure. The order of MNC content and its contribution to SOC was B > LB > L. MNC was significantly negatively correlated with PLFAs, DOC, and AP, and significantly positively correlated with pH, SOC, TN, AN, TP, Shannon–Wiener and Pielou indices. In conclusion, this study demonstrates that Betula platyphylla Sukaczev forest retains more carbon, nitrogen, and phosphorus, microbial alpha diversity, and acquires more MNC, which can provide a basis for subsequent forest management and carbon sequestration projects. Full article

The pea aphid, Acyrthosiphon pisum, possesses horizontally acquired fungal carotenoid biosynthesis genes, enabling de novo production of carotenoids. Although carotenoids are known to contribute to photo-protection and coloration, their potential role in energy metabolism and population fitness under thermal stress is still unclear. This study investigated the interactive effects of temperature and light intensity on energy homeostasis and life-history traits in A. pisum. Using controlled environmental regimes, we demonstrate that light intensity significantly influenced the ATP content, development, and reproductive output of A. pisum at 12 °C, but not at 22 °C. Under cold stress (12 °C), high light intensity (5000 lux) increased ATP content by 240%, shortened the pre-reproductive period by 46%, extended reproductive duration by 62%, and enhanced the net reproductive rate (R₀) and intrinsic rate of increase (rₘ) compared to low light intensity (200 lux). These effects were abolished at the optimal temperature (22 °C), indicating a temperature-gated, light-dependent mechanism. Demographic analyses revealed that carotenoid-associated solar energy harvesting significantly improves fitness under cold conditions, likely compensating for metabolic depression. Our findings reveal a novel ecological adaptation in aphids, where horizontally transferred genes may enable light-driven energy supplementation during thermal stress. This study provides new insights into the physiological mechanisms underlying insect resilience to climate variability and highlights the importance of light as a key environmental factor in shaping life-history strategies in temperate agroecosystems. Full article

Improving the isotropic magnetic properties of FeSi electrical steels has traditionally focused on enhancing their crystallographic texture and microstructural morphology. Strengthening the cube texture within a ferritic matrix of optimal grain size is known to reduce core losses and increase magnetic induction. However, conventional cold rolling followed by annealing remains insufficient to optimise the magnetic performance of thin FeSi strips fully. This study explores an alternative approach based on grain boundary migration driven by temperature gradients combined with deformation gradients, either across the sheet thickness or between neighbouring grains, in thin, weakly deformed non-oriented (NO) electrical steel sheets. The concept relies on deformation-induced grain growth supported by rapid heat transport to promote the preferential formation of coarse grains with favourable orientations. Experimental material consisted of vacuum-degassed FeSi steel with low silicon content. Controlled deformation was introduced by temper rolling at room temperature with 2–40% thickness reductions, followed by rapid recrystallisation annealing at 950 °C. Microstructure, texture, and residual strain distributions were analysed using inverse pole figure (IPF) maps, kernel average misorientation (KAM) maps, and orientation distribution function (ODF) sections derived from electron backscattered diffraction (EBSD) data. This combined thermomechanical treatment produced coarse-grained microstructures with an enhanced cube texture component, reducing coercivity from 162 A/m to 65 A/m. These results demonstrate that temper rolling combined with dynamic annealing can surpass the limitations of conventional processing routes for NO FeSi steels. Full article

Disorders in soybean seed-filling can lead to wrinkled seeds, affecting yield and quality. Previous studies have demonstrated that some soybean cultivars from Jiamusi, Heilongjiang Province (cold-temperate continental monsoon, ~3.5 °C mean annual temperature, ~530 mm precipitation) exhibit seed-filling disorders when cultivated in Shenyang, Liaoning Province (mid-temperate semi-humid continental monsoon, ~8.3 °C, ~610 mm). However, the causes and regulatory mechanisms remain unclear. In this study, Henong 76 (a soybean cultivar with seeds less prone to wrinkling) and Heihe 43 (a soybean cultivar with seeds prone to wrinkling) were used as experimental materials. They were sown simultaneously in Jiamusi and Shenyang, respectively, to explore the causes of seed-filling disorders in Heihe 43. The results indicated that there were significant differences in the contents of soluble sugars and starch, as well as in the activities of sucrose synthase and invertase, between the seeds of Henong 76 and Heihe 43 grown in Shenyang. However, no significant differences were found between them in Jiamusi. Transcriptomic and metabolomic analyses suggested that genes related to controlling starch hydrolysis (isoamylase, α-amylase, and glycogen phosphorylase) and sucrose synthesis and decomposition (sucrose synthase, invertase, glucose-6-phosphate isomerase, and phosphoglucomutase) in Heihe 43 were upregulated in Shenyang. In contrast, genes regulating plant hormone signal transduction (auxin, gibberellin, abscisic acid, and cytokinin) were generally downregulated. These changes led to differences in metabolites, resulting in the occurrence of seed-filling disorders. Furthermore, we analyzed the climatic conditions of the two cultivars during the soybean seed-filling period. The results indicated that high temperature might be the primary meteorological factor contributing to the occurrence of seed-filling disorders. All results indicated that the insufficient accumulation of sugars in seeds due to exposure to high temperatures during the seed-filling period is the primary cause of the prone-to-wrinkling phenomenon of the Heihe 43 cultivar under the ecological conditions of Shenyang. Full article

Three fungal strains belonging to the genus Penicillium from different temperature classes (two Antarctic strains—psychrotolerant and mesophilic, and a temperate mesophilic) were used to investigate their metabolic cell response to cold stress. The exponential- and stationary-growth-phase fungal cultures were exposed to a transient temperature downshift from optimal to 6 and 15 °C, respectively. The activity of the enzymes hexokinase, glucose-6-phosphate dehydrogenase, and glyceraldehyde 3-phosphate dehydrogenase from the glycolytic pathway, and that of the enzymes isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase from the TCA cycle were studied. In all experiments, the cold-induced oxidative stress increased the indicated enzymatic activities depending on the strain’s temperature characteristics, the degree of stress, and the growth phase. Furthermore, enzyme activity was lower in cells from stationary-phase cultures (older cells) compared to those from exponential-phase cultures (younger cells). The cellular response was more pronounced in mesophilic strains, regardless of the location of isolation. The cold-adapted Antarctic psychrotolerant strain exhibited enhanced tolerance to low-temperature stress compared to mesophilic strains. These findings emphasize the significance of temperature preferences and growth phase in the survival of fungi under conditions of cold-induced oxidative stress. New information could prove beneficial in forecasting the behaviour of fungal pathogens such as plant pathogens in agriculture and human pathogens in medicine. Full article

The rural dwelling in southern Ecuador’s Andean region is the product of a long-term process of cultural and technical hybridization in which colonial typologies are overlaid with local building know-how adapted to temperate and cold climates. This study examines how intermediate spaces—portals, hallways, patios, porches, and corridors—operate as fundamental strategies for social sustainability. These spaces facilitate interaction between domestic interiors and the surrounding environment, mediate social relations, and accommodate productive, ritual, and everyday practices. Methodologically, the research integrates morphological and typological analysis with ethnographic methods and detailed graphic representations, yielding a spatial ethnography of thirty-five dwellings distributed across distinct ecological zones of Loja Province. The findings reveal how intermediate spaces undergo transformation, appropriation, and reconfiguration over time, demonstrating notable functional adaptability while maintaining cultural continuity. Beyond environmental and climatic functions, these spaces act as vital hubs of community life, sustaining intergenerational knowledge transmission, syncretic rituals, and household microeconomies. Their logics of spatial mediation and multifunctionality position them as key architectural devices that foster the social and cultural resilience of Andean rural housing. Understanding their configuration and use offers actionable insights for contemporary design, enabling the critical reinterpretation of vernacular principles to address ongoing challenges of habitability, sustainability, and belonging in evolving rural contexts. Full article

Returning crop residues to soil is fundamental to sustainable agriculture, yet its adoption in cold-climate regions is hampered by an agronomic paradox: surface mulching conserves water but suppresses the spring soil temperatures required for crop establishment. In the present study, through a nine-year field experiment in a Mollisol under continuous maize cultivation, it was demonstrated that the method of maize straw incorporation, not merely its rate, is the decisive factor in resolving this conflict. While surface mulching maximized water conservation, it induced severe soil cooling and showed minimal gains in soil fertility. In contrast, incorporation via rotary tillage or deep plowing mitigated this cooling effect and proved superior for nutrient cycling. Among all strategies, rotary tillage of 50% residue (ROT-50) delivered the most balanced performance: it achieved the highest total nitrogen, substantially increased soil microbial biomass, and maintained one of the highest levels of Shannon diversity among incorporation treatments. These biogeochemical enhancements were driven by a fundamental, method-induced shift in the bacterial community from an oligotrophic to a copiotrophic structure. These findings shift the paradigm from a focus on residue quantity to one on incorporation method, providing a robust framework for reconciling crop productivity with long-term soil health in temperate agroecosystems. Full article

Crown fires are a major disturbance in boreal and cold–temperate forests worldwide, threatening both ecosystems and human activities. The Da Xing’anling Mountains of Northeast China exemplify these dangers due to their complex vegetation and high crown fire potential. Crown fire occurrence depends on vertical fuel continuity, fuel load, heating value, surface fire spread rate, and critical fireline intensity. However, many assessments rely on single-factor metrics or low-adaptability simulations. This study developed a Potential Canopy Fire Danger Index (PCDI) that integrates five parameters—fuel vertical distribution continuity index, fuel loading, heating value, surface fire rate of spread, and critical fireline intensity—based on field surveys and combustion tests. Pinus pumila (Regel, 1861), with its dense shrub layer, showed the highest PCDI values (0.502, 0.583 and 0.527), whereas other forest types generally fell in the low to low–moderate range (0.350–0.450), with ≈75% of plots within these classes. Surface fire spread rate correlated most strongly with PCDI, followed by vertical fuel continuity, heating value, and fuel load; critical fireline intensity had minimal influence. The elevated hazard in P. pumila reflects its structural and fuel characteristics, while other forest types present comparatively lower dangers. Model checks indicated high stability and agreement with BehavePlus 6.0 scenarios, with the PCDI showing the lowest sample SD. The PCDI provides a quantitative framework for assessing crown fire danger in cold–temperate forests and supports targeted mitigation—prioritizing P. pumila while employing cost-effective maintenance in low-danger forest types. Full article

The urbanisation process of cities disrupts the natural energy balance and surface radiation, making cities relatively warm. While vegetation has been widely recognised as a key factor in mitigating urban heat, its effectiveness is shaped by interactions with urban morphology, surface cover types, and the background climate. This paper presents a bibliometric analysis of studies examining the role of vegetation in mitigating urban heat, with a particular focus on its interactions within the urban environment across four major Köppen–Geiger climate groups: tropical, arid, temperate, and cold. A total of 130 publications were reviewed, categorised, and analysed according to geographic distribution, study period, and methodological approaches. This review identifies underexplored areas, synthesises key findings, and summarises the most significant results. Vegetation and water bodies emerged as primary contributors to heat mitigation, along with building configuration, wind speed, and shading. Temperate climates were the most frequently studied. Remote sensing was the predominant methodological approach, followed by fixed in situ observations. Meso-scale studies, examining entire cities and their surroundings, dominated in terms of spatial scale. This review offers methodological recommendations for analysing urban vegetation within the context of urban climate research. As climate change intensifies, it is increasingly important to design and implement adaptation strategies that incorporate but are not limited to vegetation. Such strategies are essential to supporting sustainable and resilient urban development in diverse climatic contexts. Full article

The Greater and Lesser Khingan Mountains ecotone exhibits transitional characteristics between northern coniferous forests and cold-temperate mixed coniferous-broadleaf forests. However, it remains unknown how vegetation characteristics and soil properties jointly influence the structural patterns of soil microbial communities within the forest systems of this ecological transition zone. Therefore, we used high-throughput sequencing and soil physicochemical analysis to investigate the response mechanisms of soil microbial communities during forest succession (five representative natural secondary forests) and their environmental driving factors. The results showed that the bacterial communities in the Greater and Lesser Khingan Mountains ecotone were primarily dominated by Proteobacteria, Acidobacteriota, Actinobacteriota, Chloroflexi, and Verrucomicrobiota, while the fungal communities were primarily dominated by Basidiomycota and Ascomycota. Their relative abundances exhibited significant differences dependent on vegetation types. Different vegetation types significantly influenced the α-diversity of soil microbial communities at the study site; however, there were no significant differences in microbial α-diversity except for the bacterial Chao 1 index. The pH, NO₃⁻-N, NH₄⁺-N, MAOC, TN, TP, and DOC significantly influenced bacterial communities, while DOC and pH were the key environmental factors shaping soil fungal communities. This study reveals the synergistic succession patterns among vegetation, soil, and microorganisms, providing a microbiological basis for high-latitude cold-region forest restoration under climate change. Full article

Building geometric parameters are key factors influencing energy-efficient building design. However, the systematic influence of building geometric parameters on energy use intensity (EUI) across varying climate regions and building envelope thermal performance levels remains incompletely elucidated, hindering the quantitative assessment of their energy-saving benefits in diverse regions and operational scenarios. This study employs a zonal sensor-optimized coupled daylighting–thermal simulation to analyze the impact of building geometric parameters and their values on annual total EUI across different climate regions and building envelope thermal performance levels. The interquartile range (IQR), sensitivity analysis (SA), and energy saving rate (ESR) analysis are utilized. The results showed the following: (1) The energy-saving benefits of geometric parameters were the greatest in severe cold (SevC) and temperate regions (TRs), with IQRs ranging from 28.50 to 39.87 kWh/m², followed by hot summer–warm winter (HS-WW), cold (Cld), and hot summer–cold winter (HS-CW) regions. While high-performance building envelopes significantly reduce EUI, the energy-saving benefits associated with geometric parameters remain undiminished. (2) The WWR is the parameter most sensitive to EUI, with SA reaching a maximum of 41.19%, notably exceeding 20% in HS-CW regions, HS-WW regions, and TRs; floor height has the lowest sensitivity, with SA reaching a maximum of 5.65%. (3) In different climate regions, the influence of floor height and building footprint area on the ESR shifts between positive and negative correlations, while the WWR and window sill height consistently exhibit positive correlations with the ESR in all climate regions. This study provides a quantitative decision-making basis for optimizing building geometric parameters in different climate regions to achieve high-performance building shapes during the early stages of architectural design. Full article

Crown fire hazard assessment and behavior prediction in dwarf pine (Pinus pumila) forests are dictated by the amount of canopy fuel available, topography, and weather. In this study, we collected data on CFL (available canopy fuel load), CBD (canopy bulk density), and CBH (canopy base height) through the destructive sampling of dwarf pine trees in the Greater Khingan Mountains of Northeast China. Allometric equations were developed for estimating the canopy’s available biomass, CFL, and CBD to support the assessment of canopy fuel. Three burning scenarios were designed to investigate the impact of various environmental parameters on fire behavior. Our findings indicated that the average CFL of a dwarf pine was 0.36 kg·m⁻², while the average CBD was measured at 0.17 kg·m⁻³. The vertical variation trends of both CFL and CBD exhibited consistency, with values increasing progressively from the bottom to the top of the tree crown. Fire behavior simulations indicated that the low CBH of dwarf pine trees increased the likelihood of crown fires. Various factors, including wind speed, slope, and CBH, exerted considerable influence on fire behavior, with wind speed emerging as the most critical determinant. Silvicultural treatments, such as thinning and pruning, may effectively reduce fuel loads and elevate the canopy base height, thereby decreasing both the probability and intensity of crown fires. Full article

Amelanchier Medik. (Rosaceae) is a genus of perennial, deciduous shrubs and trees distributed across temperate and boreal regions of the Northern Hemisphere. Traditionally, Native American communities used fruits, leaves, bark, and roots to treat digestive ailments, fevers, colds, inflammation, and to promote general well-being. Scientific investigation began with molecular studies in 1946 and phytochemical research in 1978, with research activity on some Amelanchier species increasing substantially between 2010 and 2025. Fruits are rich in phenolic compounds—particularly flavonoids and anthocyanins—along with triterpenes, carotenoids, vitamins, and minerals. Pharmacological studies of selected species report antioxidant, anti-inflammatory, anticancer, antidiabetic, antibacterial, and antiviral activities. Despite extensive chemical profiling in several members of the genus, the biological and toxicological properties of Amelanchier remain insufficiently explored, and clinical evidence is lacking. This review synthesizes recent findings on the phytochemistry, medicinal applications, and biological effects of Amelanchier species, linking traditional knowledge with modern research and highlighting priorities for future biomedical investigation. Full article

The application of marine algae-derived biostimulants offers a sustainable approach to improving plant performance in aromatic and medicinal crops. This study investigated the effects of four macroalgal extracts and two commercial biostimulant products on the growth, physiology, and essential oil production of Lavandula angustifolia cultivated under greenhouse conditions at CREA, Pescia (Italy). Treatments included extracts from Ascophyllum nodosum (France and Greenland), Laminaria digitata (Iceland), Sargassum muticum (Italy), two commercial formulations (a seaweed-based and an amino acid-based biostimulant), and a control receiving only standard fertilization. Over a 10-week period, plants were evaluated for multiple parameters: plant height, leaf number and area, SPAD index (chlorophyll content), above- and below-ground biomass, flower production, microbial activity in the growth substrate, and essential oil yield. Algae extracts, particularly those from A. nodosum (Greenland) and S. muticum (Venice), significantly enhanced most parameters compared to the control and commercial products. These treatments yielded higher biomass, greater chlorophyll retention, increased flower number, and improved essential oil content. Rhizosphere microbial counts were also elevated, indicating a positive interaction between algae treatments and substrate biology. The study highlights the multifunctional nature of marine algae, whose complex composition of bioactive compounds appears to promote plant growth and secondary metabolism through multiple pathways. The superior performance of cold- and temperate-climate algae suggests a relationship between environmental origin and biostimulant efficacy. Compared to commercial inputs, the tested algae extracts showed broader and more consistent effects. These findings support the integration of macroalgae-based biostimulants into sustainable lavender cultivation strategies. Further research is recommended to optimize formulations, validate field performance, and explore synergistic effects with beneficial microbes or organic inputs. Full article