| 1. |
- Vandvik, Vigdis, et al.
(författare)
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Plant traits and associated data from a warming experiment, a seabird colony, and along elevation in Svalbard
- 2023
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Ingår i: Scientific Data. - 2052-4463. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- The Arctic is warming at a rate four times the global average, while also being exposed to other global environmental changes, resulting in widespread vegetation and ecosystem change. Integrating functional trait-based approaches with multi-level vegetation, ecosystem, and landscape data enables a holistic understanding of the drivers and consequences of these changes. In two High Arctic study systems near Longyearbyen, Svalbard, a 20-year ITEX warming experiment and elevational gradients with and without nutrient input from nesting seabirds, we collected data on vegetation composition and structure, plant functional traits, ecosystem fluxes, multispectral remote sensing, and microclimate. The dataset contains 1,962 plant records and 16,160 trait measurements from 34 vascular plant taxa, for 9 of which these are the first published trait data. By integrating these comprehensive data, we bridge knowledge gaps and expand trait data coverage, including on intraspecific trait variation. These data can offer insights into ecosystem functioning and provide baselines to assess climate and environmental change impacts. Such knowledge is crucial for effective conservation and management in these vulnerable regions.
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| 2. |
- Antonsson, Karin, et al.
(författare)
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Quantitative palaeotemperature records inferred from fossil pollen and chironomid assemblages from Lake Gilltjärnen, northern central Sweden
- 2006
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Ingår i: Journal of Quaternary Science. - : Wiley. - 0267-8179 .- 1099-1417. ; 21:8, s. 831-841
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Tidskriftsartikel (refereegranskat)abstract
- Palaeotemperature reconstructions based on radiocarbon-dated fossil pollen and chironomid stratigraphies obtained from Lake Gilltjarnen provide evidence of climate changes during the last 11 000 years in the boreal zone of northern central Sweden. The records show consistent trends during the early and mid-Holocene, indicating low temperatures at 11 000-10 000 cal. yr BP, followed by a rising trend and a period of maximum values from about 7000 to 4000 cal. yr BP. At 3000 cal. yrBP the chironomid-inferred temperature values rise abruptly, deviating from the late-Holocene cooling trend indicated by the pollen-based reconstruction and most of the other palaeotemperature records from central Scandinavia, probably as a result of local limnological changes in Lake Gilltjarnen and its catchment. Comparison of the present results with a lake-level reconstruction from Lake Ljustjarnen, ca. 100 km southwest of Lake Gilitjarnen, shows that the low early-Holocene temperatures were associated with high lake-levels at 10500-8500 cal. yrBP, whereas low lake-levels and dry conditions prevailed during the period of high temperatures at between 7500 and 5000 cal. yr BP, probably due to high summer evapotranspiration and lower precipitation.
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| 3. |
- Geange, Sonya R., et al.
(författare)
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Next-generation field courses : Integrating Open Science and online learning
- 2021
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 11:8, s. 3577-3587
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Tidskriftsartikel (refereegranskat)abstract
- As Open Science practices become more commonplace, there is a need for the next generation of scientists to be well versed in these aspects of scientific research. Yet, many training opportunities for early career researchers (ECRs) could better emphasize or integrate Open Science elements. Field courses provide opportunities for ECRs to apply theoretical knowledge, practice new methodological approaches, and gain an appreciation for the challenges of real-life research, and could provide an excellent platform for integrating training in Open Science practices. Our recent experience, as primarily ECRs engaged in a field course interrupted by COVID-19, led us to reflect on the potential to enhance learning outcomes in field courses by integrating Open Science practices and online learning components. Specifically, we highlight the opportunity for field courses to align teaching activities with the recent developments and trends in how we conduct research, including training in: publishing registered reports, collecting data using standardized methods, adopting high-quality data documentation, managing data through reproducible workflows, and sharing and publishing data through appropriate channels. We also discuss how field courses can use online tools to optimize time in the field, develop open access resources, and cultivate collaborations. By integrating these elements, we suggest that the next generation of field courses will offer excellent arenas for participants to adopt Open Science practices.
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| 4. |
- Halbritter, Aud H., et al.
(författare)
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Plant trait and vegetation data along a 1314 m elevation gradient with fire history in Puna grasslands, Perú
- 2024
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Ingår i: SCIENTIFIC DATA. - 2052-4463. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.
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| 5. |
- Philippe, Herve, et al.
(författare)
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Acoelomorph flatworms are deuterostomes related to Xenoturbella
- 2011
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 470:7333, s. 255-260
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Tidskriftsartikel (refereegranskat)abstract
- Xenoturbellida and Acoelomorpha are marine worms with contentious ancestry. Both were originally associated with the flatworms (Platyhelminthes), but molecular data have revised their phylogenetic positions, generally linking Xenoturbellida to the deuterostomes(1,2) and positioning the Acoelomorpha as the most basally branching bilaterian group(s)(3-6). Recent phylogenomic data suggested that Xenoturbellida and Acoelomorpha are sister taxa and together constitute an early branch of Bilateria(7). Here we assemble three independent data sets-mitochondrial genes, a phylogenomic data set of 38,330 amino-acid positions and new microRNA (miRNA) complements-and show that the position of Acoelomorpha is strongly affected by a long-branch attraction (LBA) artefact. When we minimize LBA we find consistent support for a position of both acoelomorphs and Xenoturbella within the deuterostomes. The most likely phylogeny links Xenoturbella and Acoelomorpha in a clade we call Xenacoelomorpha. The Xenacoelomorpha is the sister group of the Ambulacraria (hemichordates and echinoderms). We show that analyses of miRNA complements(8) have been affected by character loss in the acoels and that both groups possess one miRNA and the gene Rsb66 otherwise specific to deuterostomes. In addition, Xenoturbella shares one miRNA with the ambulacrarians, and two with the acoels. This phylogeny makes sense of the shared characteristics of Xenoturbellida and Acoelomorpha, such as ciliary ultrastructure and diffuse nervous system, and implies the loss of various deuterostome characters in the Xenacoelomorpha including coelomic cavities, through gut and gill slits.
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| 6. |
- Philippe, Herve, et al.
(författare)
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Mitigating Anticipated Effects of Systematic Errors Supports Sister-Group Relationship between Xenacoelomorpha and Ambulacraria
- 2019
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Ingår i: Current Biology. - : Elsevier BV. - 0960-9822 .- 1879-0445. ; 29:11, s. 1818-1826.e6
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Tidskriftsartikel (refereegranskat)abstract
- Xenoturbella and the acoelomorph worms (Xenacoe-lomorpha) are simple marine animals with controversial affinities. They have been placed as the sister group of all other bilaterian animals (Nephrozoa hypothesis), implying their simplicity is an ancient characteristic [1, 2]; alternatively, they have been linked to the complex Ambulacraria (echinoderms and hemichordates) in a Glade called the Xenambulacraria [3,5], suggesting their simplicity evolved by reduction from a complex ancestor. The difficulty resolving this problem implies the phylogenetic signal supporting the correct solution is weak and affected by inadequate modeling, creating a misleading non-phylogenetic signal. The idea that the Nephrozoa hypothesis might be an artifact is prompted by the faster molecular evolutionary rate observed within the Acoelomorpha. Unequal rates of evolution are known to result in the systematic artifact of long branch attraction, which would be predicted to result in an attraction between long-branch acoelomorphs and the outgroup, pulling them toward the root [6]. Other biases inadequately accommodated by the models used can also have strong effects, exacerbated in the context of short internal branches and long terminal branches [7]. We have assembled a large and informative dataset to address this problem. Analyses designed to reduce or to emphasize misleading signals show the Nephrozoa hypothesis is supported under conditions expected to exacerbate errors, and the Xenambulacraria hypothesis is preferred in conditions designed to reduce errors. Our reanalyses of two other recently published datasets [1, 2] produce the same result. We conclude that the Xenacoelomorpha are simplified relatives of the Ambulacraria.
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| 7. |
- Ali, Hassan, et al.
(författare)
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Vibrational spectroscopic characterisation of salmeterol xinafoate polymorphs and a preliminary investigation of their transformation using simultaneous in situ portable Raman spectroscopy and differential scanning calorimetry
- 2008
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Ingår i: Analytica Chimica Acta. - : Elsevier BV. - 0003-2670 .- 1873-4324. ; 620:1-2, s. 103-12
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Tidskriftsartikel (refereegranskat)abstract
- Knowledge and control of the polymorphic phases of chemical compounds are important aspects of drug development in the pharmaceutical industry. Salmeterol xinafoate, a long acting beta-adrenergic receptor agonist, exists in two polymorphic Forms, I and II. Raman and near infrared spectra were obtained of these polymorphs at selected wavelengths in the range of 488-1064 nm; significant differences in the Raman and near-infrared spectra were apparent and key spectral marker bands have been identified for the vibrational spectroscopic characterisation of the individual polymorphs which were also characterised with X ray diffractometry. The solid-state transition of salmeterol xinafoate polymorphs was studied using simultaneous in situ portable Raman spectroscopy and differential scanning calorimetry isothermally between transitions. This method assisted in the unambiguous characterisation of the two polymorphic forms by providing a simultaneous probe of both the thermal and vibrational data. The study demonstrates the value of a rapid in situ analysis of a drug polymorph which can be of potential value for at-line in-process control
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| 8. |
- Andrén, Elinor, et al.
(författare)
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Reconstructing the history of eutrophication and quantifying total nitrogen reference conditions in Bothnian Sea coastal waters
- 2017
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Ingår i: Estuarine, Coastal and Shelf Science. - : Academic Press. - 0272-7714 .- 1096-0015. ; 198, s. 320-328
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Tidskriftsartikel (refereegranskat)abstract
- Reference total nitrogen (TN) concentrations for the Gårdsfjärden estuary in the central Bothnian Sea, which receives discharge from an industrial point-source, have been estimated from diatom assemblages using a transfer function. Sedimentological and diatom evidence imply a good ecological status before 1920 with an assemblage dominated by benthic taxa indicating excellent water transparency, high diatom species richness and less organic sedimentation resulting in homogeneous well oxygenated sediments. A change in the diatom assemblage starts between 1920 and 1935 when the species richness declines and the proportion of planktic taxa increases. Increased organic carbon sedimentation after 1920 led to hypoxic bottom waters, and the preservation of laminae in the sediments. The trend in the reconstructed TN-values agrees with the history of the discharge from the mill, reaching maximum impact during the high discharge between 1945 and 1990. The background condition for TN in Gårdsfjärden is 260-300 μg L-1, reconstructed until 1920.
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