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Ponto-Caspian amphipods (Crustacea, Amphipoda) and their microsporidian parasites recently established in Sweden
No full textThe invasive amphipods Dikerogammarus villosus, D. haemobaphes and Pontogammarus robustoides, which originate from the Ponto-Caspian region, are amongst Europe's most ecologically disruptive amphipods and have recently been detected in Sweden, marking their northernmost record and indicating a concerning expansion of their range. This study employed DNA barcoding to confirm the species identifications, assess population structure and trace the origins of these recently introduced populations. To improve the detection resolution in the case of D. villosus, we designed specific primers targeting two additional mitochondrial markers at genes ND5 and ATP8, enabling precise identification of the probable source populations, based on known European invasion routes and their phylogeographic structure. Our analysis identified the Western Group of D. villosus as being present in Sweden, with a probable introduction from the large lakes in the foothills of the Alps, possibly via sailing boats that were transported overland. Meanwhile, P. robustoides and D. haemobaphes appear to have invaded from the eastern and southern Baltic regions - including the Baltic States, Vistula Lagoon and Szczecin Lagoon - possibly via ballast water, ship hulls or floating debris. Additionally, we detected microsporidian infections in all three species, identifying Dictyocoela muelleri and D. berillonum as associated parasites. Given the ecological risks posed by these invasive species, coordinated monitoring, particularly along the Baltic coast, is essential for enabling rapid response efforts in the Nordic region
A framework for assessing pressures and threats reported under article 17 of the Habitats directive (92/43/EEC) in Sweden
No full textDG Environment (2022a) describes the reporting format referred to in Article 17 of Directive 92/43/EEC (Habitats Directive). The assessment of pressures and threats on Annex I habitat types and Annex II, IV, and V species is outlined in the ‘Explanatory Notes in Support of the Reporting Format Referred to in Article 17 of Directive 92/43/EEC (Habitats Directive)’(DG Environment 2022b), and the ‘Guidelines on concepts and definitions’ (DG Environment 2023). However, DG Environment (2022b, 2023) does not specify clear criteria for this assessment. This report by the SLU Swedish Species Information Centre (SSIC) aims to address this gap by providing its own interpretations and criteria for assessing pressures on species and habitat types, respectively
Transforming Data and Capacity-Limited Stock Assessment: Achieving Risk Equivalence with Hierarchical Assessment Frameworks and Auxiliary Data
No full textEnsuring the sustainability of fisheries worldwide requires that scientific advice remain effective even when data and capacity are limited. To address these challenges, we propose a hierarchical assessment framework (HAF) capable of integrating auxiliary information, such as empirical indicators for fishing pressure, within a Bayesian state-space biomass dynamic modelling framework. The aim is to provide risk-equivalent advice to ensure that management does not penalise data-limited fisheries with undue precaution (and loss of potential yield), nor expose them to a higher risk of overexploitation. To achieve this, we evaluated performance using classification skill metrics, such as true skill, for stock status relative to maximum sustainable yield (MSY)-based reference points. Results demonstrate that incorporating auxiliary data, particularly fishing mortality indices from periods of high exploitation, substantially improves the accuracy of stock status classification. Adoption of hierarchical assessment frameworks will support targeted data collection and evidence-based, adaptive fisheries management
Development of a highly efficient protoplast regeneration and transfection protocol for enhancing CRISPR genome editing of Brassica carinata
No full textBrassica carinata is an important oil crop with significant potential for food and industrial production. The application of the CRISPR/Cas9 genome editing tool in B. carinata could accelerate its breeding cycle. However, no efficient DNA-free gene editing method currently exists for this species. Protoplast-based CRISPR editing presents a promising solution, though it is often challenging for many crop species. In this study, we investigated several critical factors influencing in vitro shoot regeneration, including genotype, sugar type, selection and combination of plant growth regulators (PGRs), and culture duration on different media throughout various stages of protoplast development. As a result, we developed a highly efficient, five-stage protoplast regeneration protocol for B. carinata based on specific stages of protoplast development. Key findings of this study include the requirement for high concentrations of NAA and 2,4-D in the initial medium (MI) for cell wall formation, while a lower auxin concentration relative to cytokinin was necessary for active cell division (MII). For callus growth and shoot induction, a high cytokinin-to-auxin ratio was essential (MIII), and an even higher cytokinin-to-auxin ratio was optimal for shoot regeneration (MIV). For shoot elongation, low levels of BAP and GA3 were sufficient (MV). Our results also demonstrated that the duration of culture on different media and maintaining appropriate osmotic pressure at the early stages were crucial for successful protoplast regeneration. With this optimized protocol, we achieved an average regeneration frequency of up to 64% and a transfection efficiency of 40% using the GFP marker gene. This efficient protoplast regeneration protocol is now being employed for genome editing in our lab and is expected to significantly enhance the application of the CRISPR system in both basic research and the genetic improvement of B. carinata over the long term
Qualitative analysis on contaminants of emerging concern in Swedish landfill leachates: a snapshot of occurrence and spatio-temporal variability
No full textLandfill leachate is a complex and understudied matrix increasingly recognized as a source of contaminants of emerging concern (CECs) to the environment. This study provides a snapshot of the occurrence of CECs in Swedish landfill leachates, investigating their spatial distribution across five landfills, and their temporal pattern over a one-year period at one site. To our knowledge, this is the first study using qualitative non-target and suspect screening to characterize the spatio-temporal profile of CECs in landfill leachate. In total, 79 CECs were identified, including industrial chemicals (ICs), pharmaceuticals and personal care products (PPCPs), per- and polyfluoroalkyl substances (PFASs), pesticides, stimulants, and sweetener. Several compounds, such as triisopropyl phosphate, 1,3-diphenylguanidine, and 1,3-di-o-tolylguanidine, were reported for the first time in landfill leachate. Spatial analysis revealed a consistent presence of CECs across all sites, with 34 compounds detected in both untreated and treated leachates, indicating limited removal efficiency of existing treatment systems. Temporal monitoring at one landfill showed moderate variation, with the highest number of CECs detected in the winter samples. Persistent detection of ICs, PFASs, and pesticides at all sampling time points suggests continuous leaching and highlights the limitations of current treatment approaches. This study offers important insights into the chemical composition of Swedish landfill leachate and underscores the need for improved monitoring and treatment strategies to mitigate environmental risks associated with CECs
Pilot scale treatment of PFAS-contaminated groundwater in a subsurface flow constructed wetland-evaluating multiple plant species
No full textGroundwater contamination by per- and polyfluoroalkyl substances (PFAS) is an emerging threat to drinking water quality, highlighting the need for effective treatment solutions. This study investigated subsurface flow constructed wetlands for treating groundwater contaminated with PFAS. The wetlands used a peat, biochar, and lightweight expanded clay aggregate (LECA) filter substrate, planted with either tufted sedge (Carex elata), fiber hemp (Cannabis sativa Futura 75), or an intercropping of the two Salix clones S. Wilhelm and S. Loden. The experiment was conducted under field conditions in Sweden, during one growing season, using PFAS-contaminated groundwater impacted by landfill leachate. The study showed accumulation of PFAS in all plant species and the peat and biochar part of the filter substrate, with short-chain PFAS and perfluoroalkyl carboxylates (PFCAs) dominating when considering the whole plants (57 % and 77 % of Sigma PFAS, respectively) and long-chain PFAS and perfluoroalkyl sulfonates (PFSAs) dominating in the peat and biochar filter substrate (77 % and 54 % of Sigma PFAS, respectively). Sorption to the filter substrate was shown to be the primary mechanism for PFAS removal. The highest plant PFAS concentrations were found in leaves, followed by roots, for all species. There was a difference in the PFAS composition profile when comparing different plant tissues, with PFCAs dominating in leaves (84 % of Sigma PFAS) and PFSAs dominating in roots (66 % of Sigma PFAS). All plant species were determined to have an above-ground tissue/water phase concentrations >10/1 for C-3-PFCA (PFBA). This was also observed for C. sativa with C-4- and C-7-PFCAs (PFPeA, PFOA), and C-4- and C-5-PFSAs (PFBS, PFPeS), for C. elata with C-8-PFSA (L-PFOS), and for S. Loden with PFPeA. & sum;PFAS phytoextraction potential from landfill leachate-impacted groundwater (mg/ha yr) was estimated to be 940 +/- 670 for C. sativa, 390 +/- 310 for S. Loden, 330 +/- 160 for S. Wilhelm, and 160 +/- 56 for C. elata
Management practices that maximize alfalfa forage harvested on farms: Insights from technological groups
No full textAlfalfa (Medicago sativa L.) is essential for the US livestock industry and provides critical ecosystem services. However, a 30%-50% gap in forage harvested persists between farmers and research fields. This study surveyed 24 farmers in the US Midwest managing 38 alfalfa fields to identify practices that maximize forage harvested. Most fields were seeded in spring under vertical tillage, primarily for haylage. Fields with more than three cuts and those harvested for haylage or silage showed greater forage harvested (yield). Previous crop, type of tillage, interval between cuts, organic management, forage use, manure, sulfur (S), and potassium (K) application in the seeding year were associated with alfalfa forage harvested. Inputs in the established stand, including herbicide, boron (B), and S, further influenced productivity. Conditional inference tree analysis revealed three technological groups based on alfalfa forage harvested and management. Group 1 achieved the greatest forage harvested based on more nutrient inputs, like S, and more than three cuts for haylage and silage. Group 2 had lower forage harvested, relying more on manure than fertilizers, and with similar cutting frequency. Group 3 had the lowest forage harvested, using alfalfa for hay with fewer inputs and longer cutting intervals. Despite a relatively small sample size, these findings emphasize the importance of integrated management strategies in achieving greater alfalfa forage harvested and closing the productivity gap
The metabolomic profile of a high starch versus no starch diet in athletic horses
No full textFeeding a high amount of starch-rich grains is common practice for performance horses even though the horse has evolved to eat a grass based, i.e. low starch diet. To our knowledge, there are no studies using metabolomics to investigate the effects of a high-starch diet in horses. In this study we investigated differences in the plasma metabolic profile of 6 Standardbred horses fed a no-starch, forage-only (F) diet or a high-starch forage-concentrate (FC) diet for 29 days, respectively in a crossover design. Postprandial plasma samples were collected on the morning of day 25 of each dietary period. Metabolomics analysis of plasma using a targeted 1H NMR resulted in the quantification of 52 metabolites. Both a univariate and multivariate analysis of metabolites was performed. The univariate analysis found increased (p < 0.05) plasma concentrations of 2-hydroxybutyrate, citrate, dimethyl sulfone, hippurate, methionine, myo-inositol and proline in diet F and higher concentrations of glycine in diet FC. A PLS-DA analysis could discriminate between diets with good predictive power (Q2 (cum) = 0.745, p = 0.032 in CV-ANOVA). We conclude that diet Fwas strongest identified by metabolites originating from host-microbial co-metabolism and that the clear metabolomic profile discrimination between diets may have implications for health, performance and behaviour
GlASS - Global Aggregation of Stream Silica
No full textRiverine silicon (Si) plays a vital role in governing primary production, water quality, and carbon cycling. Climate and land cover change have altered how dissolved Si (DSi) is processed on land, transported to rivers, and cycled through aquatic ecosystems. The Global Aggregation of Stream Silica (GlASS) database was constructed to assess changes in river Si concentrations and fluxes, their relationship to other nutrients (nitrogen (N) and phosphorus (P)), and to evaluate mechanisms driving the availability of Si. GlASS includes concentrations of DSi, dissolved inorganic N (NO3, NOx, and NH4), and dissolved inorganic P (as soluble reactive P or PO4-P) at daily to quarterly time steps from 1963 to 2024; daily discharge; and watershed characteristics for 421 rivers spanning eight climate zones. Original data sources are cited, data quality assurance workflows are public, and input files to a common load model are provided. GlASS offers critical data to address questions about patterns, controls, and trajectories of global river Si biogeochemistry and stoichiometry