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A transcriptional roadmap of the yearly growth cycle in Populus trees
Get PDFPopulus species have adapted to many different boreal environments, characterized by fluctuating seasons. The environmental shifts throughout the year trigger molecular responses in trees, regulating crucial developmental processes. To study these molecular responses, we performed RNA sequencing on 207 samples from European aspen (Populus tremula) trees grown outdoors during different stages of their annual growth cycle, together with samples from hybrid aspen (Populus tremula x tremuloides hybrid T89) trees grown in controlled conditions mimicking seasonal changes in day length and temperature. This created a complete transcriptional roadmap of the yearly growth cycle of Populus trees. Co-expression network analyses produced 46 modules, 36 of which show a seasonal expression profile where many aspects were mimicked by indoor samples. However, several modules differed between outdoor and indoor conditions, indicating that important aspects of growth regulation are missed in experiments conducted under controlled conditions. The module networks identify gene hubs involved in season-specific molecular processes of Populus trees during the year. To make the dataset easily accessible, we developed POPUL-R (https://lauragarciaromanach.shinyapps.io/popul_r_mini/), a Shiny app enabling users to visualize gene expression data and create interactive networks. POPUL-R will be a valuable tool for the scientific community to explore the role of specific genes in the annual growth cycle of trees.Seasonal fluctuations induce major transcriptomic changes in aspen trees, revealing how environmental cues regulate their annual growth and adaptation cycle
Twenty years after storm Gudrun: A lasting impact on forest science that highlights the critical role of forest monitoring
Get PDFStorm Gudrun represents one of the most significant meteorological events in recent Swedish history, causing widespread forest destruction in southern Sweden. Now, 20 years after the storm, it is time to reflect on its impact on the forest sciences. We highlight key research themes that emerged in response to the storm, emphasising the critical role of research and monitoring infrastructure in facilitating the generation of valuable insights. We identified 18 articles focusing on storm Gudrun within forest-related research fields, which were, in turn, cited by over 600 subsequent studies. A citing network analysis resulted in eight research clusters, including, wind dynamics, carbon dynamics due to disturbances, spruce bark beetle responses, and storm damage in Sweden and Europe. Our review of primary literature underscores their dependence on established environmental monitoring and research infrastructure to provide essential background data. Maintaining these infrastructures is central to the advancement of forest-related sciences
Towards starch-based adhesives involving carbon dots as versatile crosslinkers
Get PDFIn this study, biobased materials, Dialdehyde starch (DAS) and Carbon Dots (CDs) were synthesised to develop debondable adhesives via the formation of reversible imine networks between aldehyde and amine groups. Potato starch (St) was oxidised using Sodium periodate (NaIO4) and the modification was confirmed using FTIR spectroscopy, thermal analyses and Environmental scanning electron microscopy (ESEM). Two types of CDs were prepared: CD1, synthesized via a hydrothermal treatment of citric acid with formamide and aniline, and CD2, a post-functionalized version of CD1, prepared through a microwave-assisted reaction with polyethylenimine (PEI). CDs were characterized using XPS, fluorescence and absorbance spectroscopy, FTIR, TGA, DSC, as well as ESEM. DAS and CDs were reacted in DMAC to form DAS-CD conjugates through Schiff base formation. In the case of CD1, the reaction occurred through amino groups at the edges, while for CD2, the primary amino groups of PEI. The curing properties of these solutions with and without hexamethylenediamine (HMDA) as an auxiliary crosslinker were evaluated through ABES using beech veneer pressed at 160 degrees C. Finally, debondability tests on veneer samples adhered with DAS-CD1 and DAS-CD2 were tested employing the reversibility of the Schiff-base connectivity motifs. Full debondability was achieved for DAS-CD1 after 1 hour in acidic solutions
The effects of climate on bat morphology across space and time
Get PDFAccording to Bergmann's and Allen's rules, climate change may drive morphological shifts in species, affecting body size and appendage length. These rules predict that species in colder climates tend to be larger and have shorter appendages to improve thermoregulation. Bats are thought to be sensitive to climate and are therefore expected to respond to climatic changes across space and time. We conducted a phylogenetic meta-analysis on > 27 000 forearm length (FAL) and body mass (BM) measurements from 20 sedentary European bat species to examine body size patterns. We assessed the relationships between body size and environmental variables (winter and summer temperatures, and summer precipitation) across geographic locations, and also analysed temporal trends in body size. We found sex-specific morphological shifts in the body size of European bats in response to temperature and precipitation patterns across space, but no clear temporal changes due to high interspecific variability. Across Europe, male FAL decreased with increasing summer and winter temperatures, and BM increased with greater precipitation. In contrast, both FAL and BM of female bats increased with summer precipitation and decreased with winter temperatures. Our data can confirm Bergmann's rule for both males and females, while females' BM variations are also related to summer precipitation, suggesting a potential link to resource availability. Allen's rule is confirmed only in males in relation to summer temperature, while in females FAL and BM decrease proportionally with increasing temperature, maintaining a constant allometric relationship incompatible with Allen's rule. This study provides new insights into sex and species-dependent morphological changes in bat body size in response to temperature and precipitation patterns. It highlights how body size variation reflects adaptations to temperature and precipitation patterns, thus providing insights into potential species-level morphological responses to climate change across Europe
Weaving values, knowledge and context to care for human-nature relationships in protected areas
Get PDFTransformative change necessitates a profound shift in how people relate to, understand, value and envision landscapes to find effective pathways for conservation science and practice. In response, we examined the relationships among broad values-biospheric, altruistic and egoistic-that work in conjunction with ecological knowledge acquisition and social-ecological contextual factors to explain specific values assigned to landscapes, visions for human-nature relationships and pro-environmental behaviour. We conducted in-person surveys with residents of the Sierra de Guadarrama in central Spain, which is embedded in an extensive network of protected areas. It includes a national park and two biosphere reserves, and it is close to the capital city of Madrid. Our data were analysed using a path model to test a series of hypothesised relationships. Our models revealed that self-transcendence (i.e. biospheric and altruistic) values as well as the combined effects of local and scientific ecological knowledge were positively associated with (i) specific values prioritising ecological aspects and care for nature, but also with multiple relational values with the landscape and some instrumental values focused on the provision of goods; (ii) visions highlighting a prominent role of nature over humans for the surrounding landscape (eco-centric); (iii) and pro-environmental willingness and behaviour. Indirect positive associations included social-ecological factors such as the intensity of experiences with and learning about nature, lower levels of urbanity and the combined effects of age and income. Our results revealed that these are the kinds of values that, in general, newcomers would be more likely to foster. We conclude that inclusive plural valuations aimed at improving nature conservation interventions should consider the roots of how people hold and assign values to landscapes, envision their relationship with nature and vary in their intentions to perform pro-environmental behaviours for leveraging transformative change around protected areas. An integrative and holistic social-ecological systems perspective will improve human-nature relationships in conservation research and practice. We therefore call for more explicit consideration of the combined associations of social-ecological context, broad values and knowledge systems to expand and articulate the multilevel value of interest groups in protected area management contexts.Read the free Plain Language Summary for this article on the Journal blog.El cambio transformador requiere un giro profundo en la forma en que las personas se relacionan con los paisajes, los entienden, los valoran y los conciben, a fin de encontrar v & iacute;as eficaces para la ciencia y la pr & aacute;ctica de la conservaci & oacute;n. En respuesta, examinamos las relaciones entre valores humanos amplios -biosf & eacute;ricos, altruistas y ego & iacute;stas-, la adquisici & oacute;n de diversos conocimientos ecol & oacute;gicos, y los factores contextuales socio ecol & oacute;gicos para explicar los valores espec & iacute;ficos asignados a los paisajes, las visiones de las relaciones entre los seres humanos y la naturaleza, as & iacute; como el comportamiento proambiental. Realizamos encuestas a residentes de la Sierra de Guadarrama, en el centro de Espa & ntilde;a, que est & aacute; integrada en una extensa red de & aacute;reas protegidas. Incluye un parque nacional y dos reservas de la biosfera, y est & aacute; cerca de la capital, Madrid. Nuestros datos se analizaron mediante un modelo de trayectorias para probar una serie de relaciones hipotetizadas. Nuestros modelos revelaron que los valores de autotrascendencia (es decir, biosf & eacute;ricos y altruistas), as & iacute; como los efectos combinados de los conocimientos ecol & oacute;gicos locales y cient & iacute;ficos, se asociaban positivamente con (i) valores espec & iacute;ficos que priorizaban los aspectos ecol & oacute;gicos y el cuidado de la naturaleza, pero tambi & eacute;n con m & uacute;ltiples valores relacionales con el paisaje, y algunos valores instrumentales centrados en la provisi & oacute;n de recursos materiales, (ii) visiones que destacaban un papel preponderante de la naturaleza sobre los seres humanos para el paisaje circundante (eco-c & eacute;ntricas), (iii) y la voluntad y el comportamiento proambientales. Las asociaciones positivas indirectas inclu & iacute;an factores socio-ecol & oacute;gicos como la intensidad de las experiencias con la naturaleza y el aprendizaje sobre ella, niveles m & aacute;s bajos de urbanismo y los efectos combinados de la edad y los ingresos. Nuestros resultados revelaron que estos son los tipos de valores que, en general, los reci & eacute;n llegados ser & iacute;an m & aacute;s propensos a fomentar. Concluimos que las valoraciones plurales inclusivas destinadas a mejorar las intervenciones de conservaci & oacute;n de la naturaleza deber & iacute;an tener en cuenta las ra & iacute;ces de c & oacute;mo las personas poseen y asignan valores a los paisajes, conciben su relaci & oacute;n con la naturaleza y var & iacute;an en sus intenciones de realizar comportamientos proambientales para impulsar un cambio transformador en torno a las & aacute;reas protegidas. Una perspectiva integradora y hol & iacute;stica de los sistemas socio-ecol & oacute;gicos mejorar & aacute; las relaciones entre los seres humanos y la naturaleza en la investigaci & oacute;n y la pr & aacute;ctica de la conservaci & oacute;n. Por lo tanto, llamamos a una consideraci & oacute;n m & aacute;s expl & iacute;cita de las asociaciones combinadas del contexto socio-ecol & oacute;gico, los valores humanos generales y los sistemas diversos de conocimiento para ampliar y articular los valores multinivel de los grupos de inter & eacute;s en el contexto de gesti & oacute;n de las & aacute;reas protegidas
Impacts of an anxiolytic drug on fish behaviour and habitat use in a natural landscape
Get PDFPharmaceutical contaminants reaching natural aquatic ecosystems can affect fish behaviour, modifying activity patterns, foraging behaviour and antipredator responses. While laboratory-based studies can offer key insights, assessing the ecological relevance of these findings requires field-based approaches. Therefore, we examined the effects of oxazepam, a widely prescribed anxiolytic drug, on the behaviour of a cyprinid fish (the common roach, Rutilus rutilus) in the wild, combining slow-release exposure implants with continuous tracking via acoustic telemetry. To add ecological realism, we created a landscape of fear with an uneven distribution of resources (macrophytes) and exposure to predators (pike, Esox lucius), additionally testing the effects of the drug on roach habitat selection and predator-prey interactions. Fish exposed to the drug showed an increased swimming activity and speed, but exhibited a more constrained spatial distribution in the pond, favouring areas with higher refuge availability. Both exposed and unexposed fish modified their habitat use in the presence of predators. Exposed fish appeared to get closer to the predators when these were caged, but not when predators were free-roaming. Our findings highlight the importance of considering ecological context to understand how pharmaceuticals affect fish behaviour, which is crucial for assessing risks at population and ecosystem levels
Exploring reversibility and contrasting patterns in temperature-size relationships across spatial and temporal scales using subfossil chironomids
No full textThe extent to which different magnitudes and directions of temperature fluctuations explain long-term trends in aquatic invertebrate body size is largely unknown. Using elevational gradients and paleolimnological reconstructions, we tested the hypotheses that the size of subfossil chironomid (non-biting midges) head capsules (HCs) will covary with temperature changes, with opposite morphometric changes occurring during warming and cooling phases, and that body size variation can be modified by other environmental conditions unassociated with temperature variations. Results indicated that the effects of increasing temperatures on chironomid HC size were reversed when temperatures decreased, with both warming and cooling producing similar effect sizes, corresponding to a change in HC length of similar to 3% per 1 degrees C. Additionally, our results showed that other environmental drivers can mask temperature effects on chironomid HC sizes. Specifically, we found that bottom water oxygen concentration was negatively associated with HC lengths of Chironomus anthracinus-type. We hypothesize that this pattern is driven by prolonged larval development in oxygen-depleted lakes and/or changes in basal food sources used by chironomid larvae, ultimately affecting their final body size. Future research should focus on disentangling the multiple drivers that control body size in aquatic insects, given their potential to either enhance or confound the temperature-size relationship, to improve our mechanistic understanding of aquatic insect size variation over long timescales
Evolution of phenotypic plasticity during environmental fluctuations
No full textEvolution in variable environments is predicted to disfavour genetic canalization and instead select for alternative strategies, such as phenotypic plasticity or possibly bet-hedging, depending on the accuracy of environmental cues and type of variation. While these two alternatives are often contrasted in theoretical studies, their evolution are seldom studied together in empirical work. We used experimental evolution for 30 generations in the nematode worm Caenorhabditis remanei to simultaneously study the evolution of plasticity and bet-hedging in environments differing only in their temperature variability, where one regime is exposed to faster temperature cycles between 20 and 25 degrees C, with little autocorrelation between parent and offspring environment, while the other regime had slowly increasing temperature with high autocorrelation in temperature between parent and offspring. These two environments had the same average temperature over evolutionary time, but one varied with larger magnitude on a shorter time scale. After experimental evolution, we scored adult size and fitness in full siblings reared in two different temperatures, optimal 20 degrees C and mildly stressful 25 degrees C. Experimental evolution in fast temperature cycles resulted in the evolution of increased body size plasticity but not increased bet-hedging, compared to evolution in the slowly changing environment. Plasticity followed the temperature-size rule as size decreased with increasing temperature and this plastic response was adaptive. In addition, we documented substantial standing genetic variation in body size, which represents a potential for further evolutionary change
In Silico Frontiers Shaping the Next Generation of Transformation Product Prediction and Toxicological Assessment
No full textThe characterization of transformation products (TPs) is crucial for understanding chemical fate and potential environmental hazards. TPs form through (a)biotic processes and can be detected in environmental concentrations comparable to or even exceeding their parent compounds, indicating toxicological relevance. However, identifying them is challenging due to the complexity of transformation processes and insufficient data. In silico methods for predicting TP formation and toxicity are efficient and support prioritization for chemical risk assessment, yet require sufficient data for improved results. This perspective article explores the role of computational approaches in assessing TPs and their potential effects, including rule-based models, machine learning-based methods, and QSAR-based toxicity predictions, focusing on openly available tools. While integrating these approaches into computational workflows can support regulatory decision-making and prioritization strategies, predictive models can face limitations related to applicability domains, data biases, and mechanistic uncertainties. To better communicate the results of in silico predictions, a framework of four distinct levels of confidence is proposed to support the integration of TP prediction and toxicity assessment into computational pipelines. This article highlights current advances, challenges, and future directions in applying in silico methodologies for TP evaluation, emphasizing the need for more data and expert interpretation to enhance model reliability and regulatory applicability
