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Priority effects can be explained by competitive traits
Get PDFPriority effects, the effects of early-arriving species on late-arriving species, are caused by niche preemption and/or niche modification. The strength of priority effects can be determined by the extent of niche preemption and/or modification by the early-arriving species; however, the strength of priority effects may also be influenced by the late-arriving species, as some species may be better adapted to deal with niche preemption and/or modification. Therefore, some combinations of species will likely lead to stronger priority effects than others. We tested priority effects for all pairwise combinations of 15 plant species, including grasses, legumes, and nonleguminous forbs, by comparing simultaneous and sequential arrival orders in a 10-week-long, controlled, pot experiment. We did this by using the competitive effect and response framework, quantifying the ability to suppress a neighbor as the competitive effect and the ability to tolerate a neighbor as the competitive response. We found that when arriving simultaneously, species that caused strong competitive effects also had weaker competitive responses. When arriving sequentially, species that caused strong priority effects when arriving early also had weaker responses to priority effects when arriving late. Among plant functional groups, legumes had the weakest response to priority effects. We also measured plant functional traits related to the plant economic spectrum, which were combined into a principal components analysis (PCA) where the first axis represented a conservative-to-acquisitive trait gradient. Using the PCA species scores, we showed that both the traits of the focal and the neighboring species determined the outcome of competition. Trait dissimilarities between the focal and neighboring species were more important when species arrived sequentially than when species arrived simultaneously. Specifically, priority effects only became weaker when the late-arriving species was more acquisitive than the early-arriving species. Together, our findings show that traits and specifically the interaction of traits between species are more important in determining competition outcomes when species arrive sequentially (i.e., with priority effects present) than when arriving simultaneously
Planering för gemenskap: Hur social infrastruktur formas på stadsdelsnivå
Get PDFI samhällsplaneringen efterfrågas tillvägagångssätt och instrument för att bemöta, förebygga och förhindra problem såsom otrygghet, segregation, och för att uppnå mål om social hållbarhet. Begreppet social infrastruktur har, framför allt i ett anglosaxiskt sammanhang, vuxit fram som en strategi för att integrera sociala mål med samhällsplanering och därigenom ett konkret sätt att arbeta med social hållbarhet. Social infrastruktur definieras här som nätverk av platser, anläggningar, institutioner, organisationer och grupper som skapar möjligheter för människor att mötas, bygga upp sociala relationer och i förlängningen ökad gemenskap. Flera städer i till exempel Storbritannien har utvecklat policyer för social infrastruktur som en del av den övergripande samhällsplaneringen.I den här rapporten undersöker vi vilka aspekter som bör ingå i en policy för social infrastruktur för att främja social hållbarhet på stadsdelsnivå. Genom en kombination av platsbesök, GIS-analyser, dokumentstudier och semistrukturerade intervjuer har förutsättningar för social infrastruktur i Helsingborgs två stadsdelar, Planteringen och Fredriksdal, kartlagts och undersökts. Med utgångspunkt i ett analytiskt ramverk om policyarrangemang visar vi vilket organisatoriskt sammanhang som möjliggör utveckling av social infrastruktur. I studien konstaterar vi att mötesplatserna utvecklas utifrån lokala målsättningar om trygghet, gemenskap, hälsa och demokrati, samt ett stärkt föreningsliv. Mötesplatserna möjliggörs av å ena sidan åtskilda förvaltningsövergripande utvecklingsprocesser, och å andra sidan av föreningar som etablerar sig i stadsdelarna. Det förekommer även strategiska samverkansinitiativ där exempelvis kommunen i partnerskap med det kommunala bostadsbolaget och lokala föreningar driver mötesplatser. Etableringen av nya mötesplatser såväl som befintliga mötesplatser och dess verksamheter regleras av olika avtal, lagar, regler och riktlinjer där Barnkonventionen är ett exempel och partnerskapsavtal, s.k. IOP-avtal, är ett annat. För att mötesplatserna ska möjliggöras och drivas har olika rumsliga, finansiella och mänskliga resurser, exempelvis tillgång till mark och lokaler, bidrag och personligt engagemang, pekats ut som avgörande.De övergripande slutsatserna som rapporten drar handlar alla om vikten av ett sammanhållet arbete för social infrastruktur på stadsdelsnivå om målet är att främja social hållbarhet genom samhällsplanering. Ett sådant arbete torde förutsätta andra och nya sätt att bedriva kommunalt utvecklings-, och planeringsarbete vilket ställer krav på ökad koordinering mellan förvaltningar såväl som aktiv samverkan med föreningslivet:1) Behov av en övergripande och samlad strategi om sociala mål. En strategi som syftar till att sociala mål som rättvisa, trygghet, hälsa, delaktighet och gemenskap kan implementeras genom mötesplatser i områdesutvecklingsprocesser generellt. Föreningar, en viktig aktör i dessa processer, bör integreras i samhällsplaneringen. 2) Stärk kommunernas organisatoriska kapacitet för långsiktig samverkan med föreningslivet och för att identifiera, förstå och stimulera civilsamhällets drivkrafter att engagera sig i ideellt arbete. Detta mot bakgrund av en övergripande förändring och ansvarsförskjutning inom välfärdssamhället, där civilsamhällets välfärdsuppdrag tilltagit det senaste decenniet, vilket anses bidragit till en professionalisering av föreningslivets organisation och kultur. Något som i sin tur kan bidra till minskat ideellt engagemang. 3) Arbeta strategiskt med rumsliga resurser. En sådan strategi synliggör skillnader i rumsliga resurser mellan stadsdelar och säkerställer att befintliga lokaler, byggnader och mark för icke kommersiella mötesplatser inte omvandlas i stadsförnyelseprocesser, samt att identifiera rumslig potential för samlokalisering av verksamheter.Att utveckla social infrastruktur stärker sociala band och tillhörighet, därigenom är det en fråga om och en del av social hållbar stadsutveckling. Rapporten visar att ett integrerat arbete tvärs över kommunala förvaltningar och bolag, goda relationer till föreningslivet, och ett samlat strategiskt grepp om de idéer, aktörer, regler och resurser som tillsammans stödjer social infrastruktur är viktiga komponenter i ett sådant utvecklingsarbete
Pharmacokinetics and Alterations in Glucose and Insulin Levels After a Single Dose of Canagliflozin in Healthy Icelandic Horses
Get PDFCanagliflozin (CFZ) is a sodium-glucose cotransporter-2 inhibitor that has shown promising results as a drug for the treatment of insulin dysregulation in horses. Even though CFZ is used clinically, no pharmacokinetic data has previously been published. In this study, the pharmacokinetics of CFZ after administration of a single oral dose of 1.8 mg/kg in eight healthy Icelandic horses was examined. Additionally, the effect of treatment on glucose and insulin levels in response to a graded glucose infusion was investigated. Plasma samples for CFZ quantification were taken at 0, 0.33, 0.66, 1, 1.33, 1.66, 2, 2.33, 2.66, 3, 3.5, 4, 5, 6, 8, 12, 24, 32, and 48 h post administration. CFZ was quantified using UHPLC coupled to tandem quadrupole mass spectrometry (UHPLC-MS/MS). A non-compartmental analysis revealed key pharmacokinetic parameters, including a median Tmax of 7 h, a Cmax of 2350 ng/mL, and a t1/2Z of 28.5 h. CFZ treatment reduced glucose (AUCGLU, p = 0.001) and insulin (AUCINS, p = 0.04) response to a graded glucose infusion administered 5 h after treatment. This indicates a rapid onset of action following a single dose in healthy Icelandic horses. No obvious adverse effects related to the treatment were observed
Increasing variability in resource supply over time disrupts plant-pollinator interactions
Get PDFInsect-plant interactions are key determinants of plant and insect fitness, providing important ecosystem services around the world-including the Arctic region. Recently, it has been suggested that climate warming causes rifts between flower and pollinator phenology. To what extent the progression of pollinators matches the availability of flowers in the Arctic season is poorly known. In this study, we aimed to characterize the community phenology of flowers and insects in a rapidly changing Arctic environment from a descriptive and functional perspective. To this end, we inferred changes in resource availability from both a plant and an insect point of view, by connecting resource and consumer species through a metaweb of all the plant-insect interactions ever observed at a site. Specifically, we: (1) characterized species-specific phenology among plants and insects at two High-Arctic sites-Cambridge Bay in Nunavut, Canada, and Zackenberg in Northeast Greenland; (2) quantified competition for flowers using sticky flower mimics; (3) used information on plant-pollinator interactions to quantify supply and demand for pollinator services versus flower resources during the summer; and (4) compared patterns observed within a focal summer at each site to patterns of long-term change at Zackenberg, using a 25-year time series of plant flowering and insect phenology. Within summers, we found evidence of a general mismatch between supply and demand. Over the 25-year time series, the number of weeks per summer when resource supply fell below a standardized threshold increased significantly over time. In addition, variation in resource availability increased significantly over years. We suggest that the number of resource-poor weeks per year is increasing and becoming less predictable in the High Arctic. This will have important implications for plant pollination, pollinator fitness, and the future of the Arctic ecosystem, as both plants and their pollinators are faced with widening resource gaps
Air-filled porosity, its connectivity and relation to particulate organic matter in intact soil cores controls carbon emissions near saturation
Get PDFIn wet soils, oxygen (O2) transport in large structural pores that drain close to saturation limits SOC mineralization and C emissions. However, these effects are still poorly understood because in standard incubation experiments soils are sieved and structural pore networks are destroyed. Our objective was to investigate the effects of soil structure on C mineralization rates under wet soil conditions. We measured CO2 emissions from intact soil cores of contrasting structure taken from conventional tillage vs. no-till treatments in laboratory incubations at pressure heads ranging from saturation to -30 cm. At each drainage step, we used X-ray CT to quantify various metrics of the geometry and topology of air, soil matrix and particulate organic matter (POM). We show that CO2 emissions are regulated by the air-filled porosity connected to the soil surface, as well as by the area of the interface between this connected air phase and the soil matrix and the volume of the matrix located within 2-3 millimetres of the interface and POM in this "active" zone. All four of these variables increase concomitantly with air-entry, although in the case of no-till soils, CO2 emissions increased most rapidly during initial drainage. We attributed this to the more heterogeneous "space-filling" pore structure and a larger fraction of bio-pores found in the no-till cores. These results should help to support the development of improved models of SOC turnover taking into account the effect of soil structure and soil management
A framework for quantifying the multisectoral burden of animal disease to support decision making
Get PDFAnimal diseases have wide-ranging impacts in multiple societal arenas, including agriculture, public health and the environment. These diseases cause significant economic losses for farmers, disrupt food security and present zoonotic risks to human populations. Additionally, they contribute to antimicrobial resistance and a range of environmental issues such as greenhouse gas emissions. The societal and ecological costs of livestock diseases are frequently underrepresented or unaddressed in policy decisions and resource allocations. Social cost-benefit analysis (SCBA) offers a comprehensive framework to evaluate the broad impacts of animal diseases across different sectors. This approach aligns with the One Health concept, which seeks to integrate and optimize the health of humans, animals and the environment. Traditional economic evaluations often focus narrowly on profit maximization within the livestock sector, neglecting wider externalities such as public health and environmental impacts. In contrast, SCBA takes a multi-sectoral whole-system view, considering multiple factors to guide public and private sector investments toward maximizing societal benefits. This paper discusses three separate sector specific (Animal health, Human health, Environmental health) methodologies for quantifying the burden of animal diseases. It then discusses how these estimates can be combined to generate multisectoral estimates of the impacts of animal diseases on human societies and the environment using monetary values. Finally this paper explores how this framework can support the evaluation of interventions from a One Health perspective though SCBA. This integrated assessment framework supports informed decision-making and resource allocation, ultimately contributing to improved public health outcomes, enhanced animal welfare, and greater environmental sustainability
Paving the path toward silicon as anode material for future solid-state batteries
Get PDFSolid-state batteries (SSBs) have emerged as an important technology for powering future electric vehicles and other applications due to their potential for enhanced safety and higher energy density compared to lithium-ion batteries (LIBs). Among future energy storage systems, SSBs (either semi or full SSBs) are the most promising candidates in terms of safety, cost, performance, and compactness. There has been a great effort to utilize silicon (Si) anode in SSBs due to its high specific capacity (3590 mAh g- 1), low cost, and earth abundance. SSBs with silicon anodes displayed attractive application prospects. The current research efforts showed that there is a great need to understand electrochemical performance, especially the interphase behavior, Si material design, and advanced tools for analytical characterization. In this review, we provide insights about the Si anode design, interface issues, SEI formation, failure mechanisms, and material modifications for the development of nextgeneration Si-based SSBs of use to bridge the gap between applied research and industrial scale applications
A Novel Method to Determine the Carbon Isotopic Composition of Inositol Hexaphosphate (Phytate) in Soil by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry
Get PDFRationale: Understanding the decomposition of inositol hexaphosphate (phytate), the dominant form of organic phosphorus (OP) in soil, is vital for studying phosphorus (P) cycling in terrestrial ecosystems. However, the lack of multiple stable P isotopes complicates the study of phytate dynamics under natural conditions and over long periods. Methods: A novel method is presented to determine the carbon isotopic composition of inositol in phytate using compound-specific isotope analysis. For this purpose, phytate was extracted from soil and purified via ion exchange chromatography, followed by dephosphorylation, derivatization, and analysis using GC-MS and GC-C-IRMS. Pure compounds were also analyzed to assess protocol efficiency, identify isotopic fractionations, and apply isotopic corrections due to derivatization. Results: Phytate extracted from soil samples was identified using GC-MS chromatograms. Replicate analyses of the pure compounds indicated that the protocol is highly reproducible. The carbon isotopic composition (delta C-13) showed a high reproducibility, with values varying by less than 0.5 parts per thousand and with no detectable isotopic fractionation during sample preparation. The delta C-13 values of phytate in soil samples reflected the dominant vegetation type (C-3 or C-4) growing at the study site. Conclusions: This study offers a novel approach of determining delta C-13 values of inositol of phytate in environmental samples, offering new opportunities to investigate and quantify OP dynamics based on stable carbon isotopes
What are the potentials for local governments when participating in research on knowledge co-creation through nature-based solutions?
Get PDFNature-based solutions (NbS) have been put forward as an approach to meet many of the challenges facing cities globally, such as increased temperatures, flooding and loss of biodiversity. Co-creation is a central part of the NbS approach, with the use of urban living laboratories (ULLs) as a mechanism for supporting co-creation processes. In this perspective essay, we will reflect on the potential for knowledge co-creation of NbS within an ULL context, based on the experiences from the EU H2020-funded projects REGREEN and CONEXUS. Furthermore, we will discuss how NbS and ULLs have the potential to contribute to transformative change. This is done through elaborating on processes of knowledge co-creation, communication and learning, as well as discussing the impacts which REGREEN and similar projects could have, focusing on the role of local governmental agencies
Ecological divergence of sibling allopolyploid marsh orchids is associated with species specific plasticity and distinct fungal communities
Get PDFPhenotypic plasticity, the dynamic adjustment of traits to environmental variations, is crucial for enabling species to exploit broader niches and withstand suboptimal conditions. This adaptability is particularly relevant for newly formed allopolyploids, which possess redundant gene copies and must become established in diverse environments distinct from their parents and other relatives. By evaluating gene expression and root mycobiome among two ecologically divergent sibling allopolyploid marsh orchids (Dactylorhiza majalis and D. traunsteineri) in reciprocal transplants at localities where both species are native, we aimed to understand the drivers of species persistence in the face of interspecific gene flow. Despite consistent abiotic differences characterising the alternative environments at each locality, the majority of gene expression differences between the allopolyploids appears to be plastic. Ecologically relevant processes, such as photosynthesis and transmembrane transport, include some genes that are differentially expressed between the two orchids regardless of the environment, while others change their activity plastically in one species or the other. This suggests that although plasticity helps define the specific ecological range of each sibling allopolyploid, it also mediates gene flow between them, thereby preventing differentiation. Extending our investigations to the root mycobiome, we uncover more diverse fungal communities for either species when grown in the environment with nutrient-poor soils, indicating that both abiotic and biotic factors drive the distribution of sibling marsh orchids. Altogether, our results indicate that plasticity can simultaneously promote diversification and homogenisation of lineages, influencing the establishment and persistence of recurrently formed allopolyploid species