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Managing for heterogeneity reduces fire risk in boreal forest landscapes-A model analysis
Get PDFBoreal forests are susceptible to direct and indirect human impacts, which are intensified by climate change. Amidst these challenges, wildfires are increasingly shaping forest dynamics. Boreal forest management must be adapted to mitigate such risks. It is still unclear whether management practices such as using smaller stands, species mixtures and avoiding ditching can effectively mitigate wildfires. We develop a cellular-automata simulation approach and couple it with minimalist litter and plant water balance models to examine the influence of stand size, species composition (conifers vs. broadleaf-deciduous species), and ditching impact on fire spread. We find that smaller forest stand sizes greatly reduce landscape fire risk, where for instance, decreasing stand size from 100 to 1 hectares leads to a fivefold reduction in fire risk. Diversifying tree species composition and avoiding landscape ditching can further reduce fire risk, especially when stand size is large. The effect of forest heterogeneity on fire risk is comparable to that of variability of environmental factors such as air humidity, highlighting the importance and potential of forest heterogeneity in fire mitigation. Our model allows us to explore the complex interactions that govern wildfire behavior in intensively managed boreal landscapes, supporting wildfire risk assessments and informing the development of more sustainable and climate resilient forest management strategies
Genetic insights into distance-specific performance and ability to race barefoot in trotting horses in Sweden
Get PDFMost horses used for harness racing in Sweden are Swedish Standardbred trotters (SB), but there is also a local breed, the Swedish-Norwegian Coldblooded trotters (CB) that race in separate races and are classified as endangered. Up to now, the two breeding programmes have mainly been focused on improving racing performance. This thesis aimed to study the genetic background of new traits, and the possibility to include them in the genetic evaluation of SB and CB. More specifically, Paper I aimed to study whether racing time could be treated as genetically distinct traits over short-, medium-, and long-distance races in CB. The aim was also to study reranking among top-ranked sires and their relationship to the rest of the population, to evaluate if distance-specific performance could promote the use of stallions that are less related to the population, and to control the high inbreeding rate in CB. The results showed that racing time can be treated as one trait over all distances. Some re-ranking based on breeding values for stallions was seen across the distances. Still, the relationship between stallions was close to half-siblings, and their relationship to the rest of the population was similar for the top-ranked stallions in all distances. In Papers II–IV, two traits reflecting the trotters’ ability to race barefoot were analysed in terms of their genetic background, correlation to performance, and impact on the career length. Racing barefoot has previously been linked to improved racing speed in SB, but not all trotters have hooves that tolerate racing barefoot. Two traits, proportion of barefoot races and barefoot status, were defined for SB and CB, where low to moderate heritability was estimated, and a favourable genetic correlation to performance was found. For both breeds, the results showed that the higher the proportion of barefoot races as a young horse, the shorter the career length. In summary, a trait reflecting the ability to race barefoot seems feasible to include in the genetic evaluation. However, the possible link between a higher proportion of barefoot races at a young age and reduced career length needs to be considered
Effect of Wood Ash, Lime, and Biochar on the Establishment and Early Growth of Poplars on Acidic Soil Conditions
Get PDFPoplars are traditionally cultivated on arable land, but other land types, such as forested land and forested arable land, may also provide significant opportunities for poplar plantations without competing with food production. However, these sites often have suboptimal soil pH levels that hinder optimal poplar growth, highlighting the need for improved establishment methods to enhance both survival and growth. This study investigates the establishment and growth of poplars (Populus trichocarpa and their hybrids) at forest land and forested arable land after application of wood ash, lime, and biochar using three different application methods: (i) amendment spread on the soil (Surface), (ii) amendment mixed with the soil (Mixed), (iii) amendment placed on the planting spot (Spot). Our findings revealed that wood ash and lime application almost double growth compared to untreated plants, 3 years after planting, and that growth increased equally independently whether wood ash or lime was mixed with the soil or applied on the soil surface while Spot application method resulted in overall lower growth than the Mix and Surface method. In contrast, biochar application had a lower effect on tree growth compared to wood ash and lime. This study highlights the potential of using wood ash to improve poplar growth on sites with low soil pH and that application methods can be adapted for different site conditions, thereby supporting the early establishment of these fast-growing plantations in sites with suboptimal soil conditions
Ten practical guidelines for microclimate research in terrestrial ecosystems
Get PDFMost biodiversity dynamics and ecosystem processes on land take place in microclimates that are decoupled from the climate as measured by standardised weather stations in open, unshaded locations. As a result, microclimate monitoring is increasingly being integrated in many studies in ecology and evolution. Overviews of the protocols and measurement methods related to microclimate are needed, especially for those starting in the field and to achieve more generality and standardisation in microclimate studies. Here, we present 10 practical guidelines for ground-based research of terrestrial microclimates, covering methods and best practices from initial conceptualisation of the study to data analyses. Our guidelines encompass the significance of microclimates; the specifics of what, where, when and how to measure them; the design of microclimate studies; and the optimal approaches for analysing and sharing data for future use and collaborations. The paper is structured as a chronological guide, leading the reader through each step necessary to conduct a comprehensive microclimate study. At the end, we also discuss further research avenues and development in this field. With these 10 guidelines for microclimate monitoring, we hope to stimulate and advance microclimate research in ecology and evolution, especially under the pressing need to account for buffering or amplifying abilities of contrasting microhabitats in the context of global climate change.La majorit & eacute; des dynamiques de biodiversit & eacute; et des processus & eacute;cosyst & eacute;miques terrestres se d & eacute;roulent sous des conditions microclimatiques d & eacute;coupl & eacute;es des conditions climatiques telles qu'elles sont mesur & eacute;es par les stations m & eacute;t & eacute;orologiques standardis & eacute;es, qui sont situ & eacute;es dans des lieux ouverts et non ombrag & eacute;s. Ainsi, le suivi des conditions microclimatiques est de plus en plus int & eacute;gr & eacute; aux & eacute;tudes en & eacute;cologie et en & eacute;volution. Il est n & eacute;cessaire de synth & eacute;tiser les protocoles et m & eacute;thodes de mesure des conditions microclimatiques, pour celles et ceux qui d & eacute;butent dans ce domaine, mais aussi pour atteindre une forme de g & eacute;n & eacute;ralisation et de standardisation des approches utilis & eacute;es entre & eacute;tudes. Nous pr & eacute;sentons ici dix recommandations pour la recherche sur les microclimats terrestres, couvrant les m & eacute;thodes et les bonnes pratiques depuis la conceptualisation d'une & eacute;tude sur le microclimat jusqu'& agrave; l'analyse des donn & eacute;es microclimatiques. Nos recommandations incluent la pertinence des microclimats, les sp & eacute;cificit & eacute;s associ & eacute;es aux mesures & agrave; effectuer (o & ugrave;, quand et comment), en passant par la conception des & eacute;tudes microclimatiques, ainsi que les approches m & eacute;thodologiques optimales & agrave; utiliser pour analyser et partager les donn & eacute;es en vue d'utilisations et collaborations futures. L'article est structur & eacute; comme un guide chronologique, accompagnant le lecteur & agrave; travers chaque & eacute;tape n & eacute;cessaire pour la bonne r & eacute;alisation d'une & eacute;tude microclimatique compl & egrave;te. Nous terminons en discutant les perspectives de recherche et les d & eacute;veloppements dans ce domaine. Avec ces dix recommandations, nous esp & eacute;rons stimuler et faire progresser la recherche sur les microclimats en & eacute;cologie et en & eacute;volution, en particulier face & agrave; la n & eacute;cessit & eacute; pressante de prendre en compte les capacit & eacute;s des divers microhabitats & agrave; tamponner ou & agrave; amplifier les extr & ecirc;mes climatiques en contexte de changements climatiques.Gran parte de la din & aacute;mica de la biodiversidad y de los procesos ecosist & eacute;micos terrestres tienen lugar en microclimas desvinculados del clima medido por estaciones meteorol & oacute;gicas estandarizadas, situadas en lugares abiertos y sin sombra. Por este motivo, el monitoreo del microclima se est & aacute; integrando cada vez m & aacute;s en muchos estudios de ecolog & iacute;a y evoluci & oacute;n. Para aquellos que se inician en el trabajo de campo, y para lograr una mayor generalidad y estandarizaci & oacute;n en los estudios de microclima, se necesitan protocolos y m & eacute;todos de medici & oacute;n estandarizados relacionados con el microclima. Aqu & iacute; presentamos diez pautas pr & aacute;cticas para la investigaci & oacute;n de microclimas terrestres, que abarcan m & eacute;todos y buenas pr & aacute;cticas desde la conceptualizaci & oacute;n inicial del estudio hasta el an & aacute;lisis de datos. Nuestras pautas abarcan la importancia de los microclimas, las particularidades de qu & eacute;, d & oacute;nde, cu & aacute;ndo y c & oacute;mo medirlos, el dise & ntilde;o de los estudios sobre microclimas y los enfoques & oacute;ptimos para analizar y compartir datos para su uso y colaboraci & oacute;n futura. El art & iacute;culo est & aacute; estructurado como una gu & iacute;a cronol & oacute;gica que conduce al lector a trav & eacute;s de cada uno de los pasos necesarios para llevar a cabo un estudio exhaustivo del microclima. Al final, tambi & eacute;n se discuten futuras l & iacute;neas de investigaci & oacute;n y desarrollo en este campo. Con estas diez pautas para el monitoreo del microclima, esperamos estimular y avanzar en la investigaci & oacute;n del microclima en ecolog & iacute;a y evoluci & oacute;n, especialmente bajo la urgente necesidad de dar cuenta de las capacidades amortiguadoras o amplificadoras de microh & aacute;bitats contrastantes en el contexto del cambio clim & aacute;tico global
Socio-economic Development and Carbon Productivity: A Panel Data Analysis of the World's Largest Carbon-Emitting Countries
Get PDFAs global concerns about climate change intensify, assessing the environmental efficiency of production processes through carbon productivity has become increasingly important. This study examines the impact of socio-economic development on carbon productivity in the top 18 CO2-emitting countries, which contribute approximately 82% of global CO2 emissions, over the period 1990-2019. Using a class of econometric tests to address heterogeneity and cross-sectional dependence, we employ the Cross-Sectionally Augmented Autoregressive Distributed Lag (CS-ARDL) model for final estimation, ensuring robustness with Common Correlated Effects Mean Group (CCEMG) and Augmented Mean Group (AMG) estimations. The empirical findings reveal that GDP per capita, Trade, and FDI increase carbon productivity while energy consumption and urbanization curtail carbon productivity. The country-specific effects indicated that 83% of the sample countries exhibit positive relationships between socio-economic development and carbon productivity, suggesting that these nations can serve as models for effective low-carbon policies. Moreover, the results demonstrate bi-directional relationships for GDP per capita, FDI, and energy use with carbon productivity and uni-causal relationship for trade and urbanization. The study highlights the need for implementing stricter regulations to improve energy efficiency and promote the adoption of renewable energy sources such as wind, solar, hydro, and nuclear power. Additionally, countries should incentivize green technology investments through tax breaks and subsidies, enhance international trade agreements that support the exchange of clean technologies, and develop sustainable urban planning initiatives to mitigate the negative impact of urbanization on carbon productivity
Cultivar fingerprinting and SNP-based pedigree reconstruction in Danish heritage apple cultivars utilizing genotypic data from multiple germplasm collections in the world
Get PDFHeirloom Danish apple cultivars are historically and pomologically important, part of the cultural heritage, and have valuable adaptation to regional climate conditions. However, lack of information about their genetic identity and pedigree relatedness with other cultivars hampers proper cultivar identification, germplasm curation, genebank management, and future regional breeding efforts. Many Danish apple cultivars are maintained in the national collection "The Pometum", maintaining around 850 apple accessions. Additional material is maintained in public or private Danish collections. However, no information exists regarding genotypic duplicates between these collections and germplasm collections in other countries, pedigree inferences across collections, and genotypically unique accessions at the genebank level.To provide such information, 976 accessions from Denmark were genotyped with simple sequence repeat (SSR) markers and the Illumina Infinium 20K single nucleotide polymorphism (SNP) array. The resulting genotypic data were compared to large databases of genotypic data from germplasm collections in multiple countries to identify genotypic duplicates and conduct pedigree reconstruction. The germplasm maintains 305 unique genotypic profiles which were not found in other germplasm collections. The study exposed previously unknown synonyms, accessions not true-to-type, and novel pedigree relationships involving accessions from multiple collection sites. The most frequent parents of Danish germplasm were 'Hvid Vinter Pigeon' and 'Cox's Orange Pippin' whereas 'Reinette Franche' was the most common grandparent. The accession-level information will benefit germplasm curation, cultivar identification, genebank management, and future breeding efforts, and shed new light on cultivar history and origin
Decontamination and Surface Analysis of PFAS-Contaminated Fire Suppression System Pipes: Effects of Cleaning Agents and Temperature
Get PDFPer- and polyfluoroalkyl substances (PFAS)-containing firefighting foam have been used in stationary fire suppression systems for several decades. However, there is a lack of research on how to decontaminate PFAS-contaminated infrastructure and evaluate treatment efficiency. This study assessed the removal of PFAS from stainless steel pipe surfaces using different cleaning agents (tap water, methanol, and aqueous solutions containing 10 and 20 wt % of butyl carbitol (BC)) at different temperatures (20 °C, 40 °C, and 70 °C). The content of the remaining fluorine (F)-containing compounds on the pipe surfaces was evaluated for the first time using time-of-flight elastic recoil detection (ToF-ERD). The results showed that a 20% BC aqueous solution heated to 70 °C removed up to 40 μg/cm2 ∑PFAS from surfaces via soaking (targeted analysis). Treatment with 20% BC was 2- to 8-fold more effective than tap water at 70 °C and 10- to 20-fold more effective than tap water at 20 °C. Total fluorine analysis determined by combustion ion chromatography showed a 2- to 8-fold higher F-equivalent compared to targeted analysis in the cleaning solution after treatment, indicating the presence of a significant amount of polyfluoroalkyl PFAS. Surface analysis with ToF-ERD confirmed partial F removal from pipe surfaces throughout consecutive soaking intervals, with residual F remaining on pipe surfaces after treatment, leaving the risk of PFAS rebound into F-free firefighting foams. Furthermore, supramolecular assemblies of PFAS with at least 70 PFOS molecules/nm2 were identified by ToF-ERD on pipe interior surfaces
Native Mass Spectrometry Captures the Conformational Plasticity of Proteins with Low-Complexity Domains
Get PDFDisordered regions are an important functional feature of many multidomain proteins. A prime example is proteins in membraneless organelles, which contain folded domains that engage in specific interactions and disordered low-complexity (LC) domains that mediate liquid-liquid phase separation. Studying these complex architectures remains challenging due to their conformational variability. Native mass spectrometry (nMS) is routinely employed to analyze conformations and interactions of folded or disordered proteins; however, its ability to analyze proteins with disordered LC domains has not been investigated. Here, we analyze the ionization and conformational states of designed model proteins that recapitulate key features of proteins found in membraneless organelles. Our results show that charge state distributions (CSDs) in nMS reflect partial disorder regardless of the protein sequence, providing insights into their conformational plasticity and interactions. By applying the same CSD analysis to a spider silk protein fragment, we find that interactions between folded domains that trigger silk assembly simultaneously induce conformational changes in the LC domains. Lastly, using intact nucleosomes, we demonstrate that CSDs are a good predictor for the disorder content of complex native assemblies. We conclude that nMS reliably informs about the conformational landscape of proteins with LC domains, which is crucial for understanding protein condensates in cellular environments
Temporal dynamics of airborne fungi in Swedish forest nurseries
Get PDFIn Sweden, reforestation of managed forests relies predominantly on planting nursery-produced tree seedlings. However, the intense production using containerized cultivation systems (e.g., high seedling density, irrigation from above, regular fertilization) creates favorable conditions for fungal infections. Despite the harmful role of diseases in forest nurseries, the origin and dispersal factors of fungal pathogens remain largely unknown. A better understanding of the airborne spread of pathogens could improve the prediction of fungal infection, ultimately optimizing preventative methods and decreasing the use of fungicides. This study investigated the temporal dynamics of airborne fungi in forest nurseries, with a focus on fungal pathogens. Airborne fungi were monitored in four Swedish forest nurseries over two growing seasons using spore traps and high-throughput sequencing. Fungal pathogens were identified using bioinformatics and quantified with quantitative PCR. Results showed strong temporal shifts of airborne fungal diversity and community composition following the growing seasons. The airborne spread included high abundances of important fungal pathogens (e.g., Cladosporium sp., Botrytis cinerea, Alternaria sp., Sydowia polyspora, and Melampsora populnea) with individual temporal and spatial variations. In general, the deposited spore loads of nursery pathogens correlated positively with increased temperature and negatively with higher precipitation. This was expressed the strongest for Cladosporium sp., Alternaria sp., and M. populnea, which suggests a higher availability of fungal inoculum in warm and dry periods. This study highlights the influence of seasonality on the temporal dynamics of economically important fungal pathogens in Swedish forest nurseries, which should be considered in the development of a local decision support system
Molecular mechanisms behind the anti corona virus activity of small metal oxide nanoparticles
Get PDFThe recent COVID-19 pandemic has set a strong quest for advanced understanding of possible tracks in abating and eliminating viral infections. In the view that several families of "pristine" small oxide nanoparticles (NPs) have demonstrated viricidal activity against SARS-CoV-2, we studied the effect of two NPs, with presumably different reactivity, on two viruses aiming to evaluate two "primary suspect" routes of their antiviral activity, either specific blocking of surface proteins or causing membrane disruption. The chosen NPs were non-photoactive 3.5 nm triethanolamine terminated (surface capped) titania TiO2 NPs (TATT) and ultrasmall (1.1 nm) silicotungstate polyoxometalate (POM) NPs. The former were expected to both, interact with viral surface proteins as well as strongly complex with phosphate groups whereas the latter was not expected to form surface complexes. We demonstrated that expectedly, POM NPs up to 1.25 mM (4.5 mg l(-1)) had no significant antiviral activity towards neither of the used viruses, an enveloped transmissible gastroenteritis virus (TGEV) belonging to coronaviruses and non-enveloped encelomyocarditis virus (EMCV). At the same time, TATT NPs exhibited statistically significant (p < 0.05) antiviral activity against TGEV starting from 0.125 mM (12 mu g ml(-1)). However, no antiviral activity of TATT against non-enveloped EMCV was detected. The observation that TATT NPs showed activity only against enveloped viruses and at relatively high concentrations suggests that the effect could be related with complexation with phospholipids. Possible chemical mechanism of viral membrane disruption was investigated by a variable temperature NMR study of NP complexation with model organic phosphate molecules, proving TATT to strongly interact with them and POM remain unreacted. Viral membrane disruption by TATT NPs was additionally confirmed by demonstraing RNA leackage from TGEV upon contact with those NPs. Therefore, our study proved a new mechanism of antiviral action of titania NPs in the dark which involved membrane disruption proceeding via direct surface complexation