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Female Brown Long-Eared Bats (Plecotus auritus) Delay Roost Emergence at Elevated Natural Light Conditions
Get PDFNocturnal animals inhabiting northern latitudes face prolonged periods of reduced foraging times in summer due to short light nights. The energetic challenges of reduced foraging times are further heightened in reproductive mammals that allocate substantial resources to offspring care with peak energy demands in mid-summer. However, little is known about responses to variation in natural light conditions at high latitudes in light-averse species, such as slow-flying gleaning bats, especially during reproduction. Here, we investigate the impacts of natural light levels and other environmental conditions (i.e., temperature, rain and wind) on individual-level activity patterns (emergence time, return time, proportion of night utilised) in reproductive and non-reproductive female brown long-eared bats, Plecotus auritus (Nind = 27) in Norway (60.1 degrees N) collected across three summers (2019-2021). We found that bats delayed the start of evening foraging trips on lighter nights, typically emerging from the roost only when light levels decreased below 5 lux, likely because higher light levels are associated with increased predation risk. However, no such effect was found in morning return times to the roost, for which bats showed greater light tolerance. Lactating females took apparently higher risks and left the roost approximately 20 min earlier than non-reproductive females, presumably because of their greater energetic requirements. They also spent a larger proportion of the night away from the roost compared to pregnant and non-reproductive individuals, although this proportion was influenced by variation in environmental conditions, such as temperature, rainfall and windspeed. Our results highlight the dynamic nature of responses in light-averse bats balancing risks of predation against foraging gains during reproduction at northern latitudes. Reduced foraging times during short northern nights may thus represent a hard constraint to range expansion in slow-flying gleaning bats, even if other environmental conditions improve with climate change
Spectroscopic solutions for generating new global soil information
Get PDFWhile global efforts to operationalize soil spectroscopy are progressing, cooperation is needed to fully leverage its potential for generating digital soil information to support sustainable soil management worldwide. The Global Soil Laboratory Network's soil spectroscopy initiative (GLOSOLAN-Spec), led by the Food and Agriculture Organization of the United Nations (FAO) through its Global Soil Partnership (GSP), is dedicated to the further development and adoption of soil spectroscopy by fostering international collaboration via a scientific community of practice to produce accurate and reliable soil information for sustainable soil management and decision-making. To support this effort, we, a global consortium of soil scientists under the auspices of the International Union of Soil Sciences (IUSS) and GLOSOLAN-Spec, aim to address seven key challenges hindering the adoption of soil spectroscopy worldwide. Here, we offer perspectives on what is needed to advance soil spectroscopy as a routine soil analysis method, emphasizing its potential to generate new and reliable spatial and temporal soil data
Arginine-iron–hexametaphosphate complex as a novel nitrogen plant nutrition reducing nitrate leaching in Scots pine (Pinus sylvestris) seedling production
Get PDFThe industrial production of conifer seedlings in nurseries uses large amounts of fertilizers to ensure their proper growth and accurate nutrient status. However, inorganic nitrogen fertilization leads to nitrate leaching, which has negative environmental consequences. An alternative solution could be the use of controlled-release fertilizers that supply nutrients over longer periods and hence have a lower environmental impact. This study analysed the performance of a novel arginine–iron– hexametaphosphate complex on Scots pine (Pinus sylvestris) seedlings. The complex was characterized using a wide range of analytical tools, indicating that it is a precipitated complex rather than a crystalline compound. Plant growth on arginine–iron–hexametaphosphate was comparable to a commercial inorganic nitrogen controlled-release fertilizer but with significantly lower nitrate leaching. A nitrogen budget of seedlings and growth substrate showed that seedlings had acquired nitrogen in excess of the amount of nitrogen present at the start of the experiment, and this excess nitrogen was smaller in seedlings grown on the inorganic fertilizer. Measurements of acetylene reduction in seedlings indicated low but measurable rates of nitrogen fixation, potentially contributing to the excess nitrogen. Together, the results showed that the arginine–iron–hexametaphosphate complex is a good alternative to commonly used fertilizers and can contribute to sustainable seedling production
Role of Staphylococcus aureus Colonization in Burn Patients
Get PDFObjectives: Staphylococcus aureus is an important pathogen in burn patients and contributes to mortality, however, the role of colonization with S. aureus in the course of the disease is less well described. Methods: The study aimed to determine the frequency of S. aureus colonization in 80 patients treated in a national burn center in Uppsala, Sweden, during the first ten days of hospitalization in relation to length of stay, number of days before antibiotic treatment started and mortality; additionally, epidemiological relationship and phylogeny were analyzed. Results: A total of 38/80 (47.5%) patients tested positive for S. aureus upon admission, while 47 out of 65 patients who completed the 10-day study period (72%) were colonized with S. aureus. Patients who were colonized at admission tended to stay longer at the burn center, particularly when admitted with more severe conditions corresponding to a rBaux score >70 (p=0.05, R2=0.09). Patients carrying isolates of phylogroup 2 received antibiotic treatment approximately one day later than patients with isolates belonging to phylogroup 1 (p<0.05, R-2= 0.09). Conclusions: The study findings emphasize that screening for S. aureus colonization in burn patients upon admission, particularly in critically injured patients, could prove beneficial in optimizing antibiotic therapy. (c) 2025 The Author(s). Published by Elsevier Ltd on behalf of The British Infection Association. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
Diel Bacterioplankton Community Dynamics Under Contrasting Light Regimes
Get PDFIn the Boreal region, extreme seasonal variations in day-night length expose communities to dynamic light and temperature fluctuations. Freshwater bacterioplankton, representing key ecosystem components, faces climate-driven shifts; yet the fixed day-length patterns determined by latitude underscore the importance of studying light's role in predicting ecosystem responses. We investigated bacterial community composition in a brown peat bog and a clear oligotrophic lake across seasons with contrasting light regimes: the summer solstice (> 20 h of daylight) and the autumn equinox (equal day-night length). Using amplicon sequencing of 16S rRNA transcripts, alongside measurements of physicochemical parameters, organic matter characterisation and dissolved carbon dioxide and methane gas measurements, we found no diel cycling in the lake during either period or in the peat bog near the summer solstice. However, the structure of bacterial peat bog communities exhibited cyclic changes over diel cycles at the autumn equinox. Twelve amplicon sequence variants, including both phototrophic and heterotrophic taxa, increased in abundance at all measured morning sampling times. These findings provide valuable insights into the diel patterns of boreal lentic habitats and their bacterioplankton communities, highlighting the absence of diel fluctuations in some systems and seasons, while revealing cyclic dynamics in others, driven by conditionally rare taxa
Toward a Forest Bioeconomy
Get PDFThe forest bioeconomy is an economic paradigm that aims to replace fossil-based materials with forest-based renewable materials to advance societal aspirations for more sustainable futures. Increasing wood production to advance forest bioeconomy through intensive forest management may reduce other ecosystem benefits and create tensions with other societal demands and forest policy goals.This Thesis contributes to the growing forest bioeconomy literature by investigating the public’s perceived values on wood products and forest management intensity, and through empirical analyses of trade-offs emerging from intensive forest management. It consists of four academic papers of thematic and geographical diversity. Paper I investigated public acceptance of multi-story wooden buildings as a residential alternative across seven European countries. Results show commonly high public acceptance, with differences in the strengths of selected behavioral drivers across countries. Paper II elicited Norwegian and Swedish preferences for forest management intensity in private production forests and explored their relationships with climate change beliefs. Some differences were detected, but both sampled populations preferred less intensive management aimed at enhancing biodiversity, with such preferences positively associated with higher climate change awareness. Paper III analyzed welfare changes among the Swedish public in supporting less intensive management in private production forests through increased taxation. Analyses revealed the prevalence of two groups with contrasting welfare, highlighting the relevance of exploring voluntary support mechanisms to mitigate welfare loss. Paper IV turned to empirical analyses of potential trade-offs from the intensification in forest management supported by the forest bioeconomy in other contexts. Exemplified by the increase in industrial wood pellet production in the US state of Georgia in response to European demands for wood energy, Paper IV assessed whether it had negative impacts on forest health and found a lack of such evidence.The papers suggest that increasing wood production to pursue forest bioeconomy goals is broadly acceptable to the society. Nonetheless, public policy instruments to help balance and to continuously monitor trade-offs between wood production and other ecosystem benefits seem warranted. Any oversight measures should be tailored to specific socio-ecological conditions
Performance of elite and heritage germplasm in barley genotype mixtures: effects on yield and disease under diverse management scenarios
Get PDFGenotype mixtures are multiple crop lines grown together to improve yield, stability, and disease control by utilizing different genetic and morphological traits. Incorporating heritage germplasm may enable exploitation of low input adaptation traits while retaining the high yield of elite modern cultivars. However, the effects of nutrient application, sowing density, and disease management on competition/facilitation dynamics in genotype mixtures with diverse germplasms, such as landraces, remain largely unknown. A set of complimentary plot experiments, undertaken in the arable cropping area of the east of Scotland, assessed genotype mixtures using heritage lines and/or elite cultivars of both spring and winter barley. The experimental systems manipulated the sowing densities, mixture composition, nitrogen application, and fungal disease pressure across three different field seasons. Here we show that the advantages of genotype mixtures were highly dependent on the genotypic makeup of the mixture and the environmental conditions in which they are grown, demonstrating complex genotype mixture × environment interactions. Genotype mixture performance in barley is highly dependent on the interaction of genetic composition and management factors. This paper revealed, for the first time, that small amounts of heritage germplasm enhanced yield stability, though overall yields rarely match those of the elite monocultures and no consistent disease reduction was observed. Although barley gains limited benefits from mixing genotypes, our study is able to highlight complex trends in mixture composition and environment that are relevant for crops with greater genotype mixture yield benefits
Deep learning with CNNs for classifying damage type in wheat and grasslands
Get PDFWildlife causes significant economic losses to Swedish agriculture through their feeding behaviour in crops. Accurately assessing these losses is crucial for developing mitigation strategies and reducing conflicts between stakeholders. However, traditional ground-based surveys are labour-intensive, observer-dependent, spatially limited, and not easily scalable. Advances in remote sensing and artificial intelligence (AI) offer new opportunities for automatised to semi-automatized damage detection and mapping at very-high spatial resolution scale. In this study, we developed a deep learning approach based on Convolutional Neural Networks (CNNs) applied to UAV-derived orthomosaics to discriminate between damage types. The workflow integrated four key steps: preprocessing UAV imagery into normalized image tiles and structured datasets; optimizing model behaviour through hyperparameter tuning; training the CNN with transfer learning, where dense layers were fitted to labelled damage data while convolutional layers remained frozen; and evaluating model performance with independent test sets. Performance metrics, including accuracy, precision, recall, and F1-score, demonstrated clear differences between wheat and grasslands, as well as between training strategies. In general, models trained on crop-specific datasets outperformed those trained on the full dataset, highlighting the importance of tailoring training data to individual crop types. Across both crops, the no-grid approaches consistently achieved stronger results than grid-based models, suggesting that preserving spatial context improves classification performance. Wheat models benefited more strongly from crop-specific training, showing a pronounced gain in classification reliability compared to grasslands, where improvements were present but more moderate. When applied to full-field predictions, performance declined compared to validation polygons, indicating challenges in generalizing from controlled validation areas to more heterogeneous field conditions. Overall, the observed trends confirm that CNN-based approaches can capture relevant spectral and spatial features for damage type discrimination, with wheat classifications being particularly sensitive to training data design and quantity. These findings demonstrate the potential of CNN-based methods for UAV-assisted monitoring of crop damage and provide a foundation for scalable and semi-automatized applications in precision agriculture
Timber colonialism in the periphery: Timber frontiers and indigenous peoples land use in northern Scandinavia and southern Patagonia in the late 19th and early 20th century
Get PDFDuring the nineteenth century an intense exploitation of natural resources such as wood and timber in what was considered "marginal" or remote regions started, and was driven by an ever-increasing demand in industrialized regions. One common denominator for the timber exploitation that opened the global expansion of capitalism beyond the borders of Europe was the brutal intrusions into Indigenous territories. The overall aim of this study is to analyse two timber frontier movements in the late nineteenth and early twentieth century: one in northern Sweden and one in southern Chile, intruding into previously un-logged old-growth forests on ancestral Indigenous territories. The large-scale commercial logging began around the mid-nineteenth century in both regions. It was driven by external demand and financed by national and/or international capital. New logging entrepreneurs moved into the territories and established sawmills, brought in workers to run the sawmills, cut trees in the forest and transported the timber to the sawmills. In northern Sweden the logging industry was the main economic activity, while in southern Patagonia the logging of timber was one of several forms of natural resource exploitations complemented by mining, rangeland sheep herding and trade through the region. In both regions, the logging frontier was often intertwined with agricultural expansion promoted by the state and global capitalism. In both studied regions the colonial legacy of the nineteenth century timber frontiers has left a heavy burden on the forest landscapes, on the rights of the Indigenous peoples whose lands were exploited and on the present legal situation. Challenges for the future are to re-establish recognition of Indigenous heritage and land tenure rights in both regions, according to international conventions, as well as restoring ecological qualities to the associated forest ecosystems for the sustainability of Indigenous practices. (c) 2025 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
Mitigating Cd stress in alfalfa: the role of melatonin and nano-calcium oxide in enhancing photosynthesis and antioxidant defense
Get PDFBackgroundHeavy metal contamination, particularly cadmium (Cd), is a significant threat to agricultural productivity and food security. Melatonin, as a key biostimulant, plant growth regulator and stress resistance hormone, along with nano-calcium oxide (nCaO), can enhance plant resilience to stress. However, few studies have investigated the combined effects of melatonin and nCaO in mitigating Cd stress in plants. This study examined the effects of the combined application of melatonin (100 mu M) and nCaO (100 mg kg-1) on alfalfa (Medicago sativa L.) seedlings.ResultsUnder Cd stress, alfalfa seedlings exhibited a 43% reduction in shoot length, 50% in root length, and 60% in chlorophyll content, while increased MDA, hydrogen peroxide (H2O2) and O2 center dot- accumulation. However, the combined application of melatonin and nCaO significantly alleviated Cd toxicity, enhancing shoot and root growth by 46% and 49%, respectively. Photosynthetic efficiency improved by 70%, while chlorophyll content and Fv/Fm ratio increased by 68% and 81%, respectively. This treatment also reduced Cd accumulation in roots and shoots by 47% and 75%, while increasing calcium uptake by 84% in roots and 63% in shoots. Antioxidant enzyme activities (SOD, POD, CAT, and APX) were upregulated by 59%, 42%, 62%, and 49%, respectively, mitigating oxidative damage. The effect of combined treatment on ultrastructural analysis revealed restored chloroplast integrity and stomatal functionality under Cd stress.ConclusionThe combined application of melatonin + nano calcium oxide shows great promise for ecologically acceptable alleviation of Cd stress in alfalfa by lowering its absorption