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Combining wood supply with reindeer foraging in the same forest: Evaluation of spacing and thinning strategies
Get PDFThe forest land of northern Sweden is used for reindeer husbandry by the Indigenous S & aacute;mi while also being managed for wood supply. Modern forestry with dense pine Pinus sylvestris stands, maintained with high basal areas and high leaf areas, allow little light to reach the ground and the lichen cover. Finding sustainable forest management for low-productivity pine sites that combine lichen cover habitats with economically viable wood production is an urgent need. In this study, we compared pine regenerations resulting in 600, 1200 and 1800 trees per hectare when the stand reached a height of 10 m. In addition, we examined the effects of two thinning strategies: business as usual (BAU) follows thinning guidelines currently used in Swedish forests, whereas combined wood and lichen (CWL) features repeated heavy thinnings throughout the rotation. Results showed reduced production but a relatively small decline in economy in the CWL strategy compared to BAU, despite a large reduction in basal area. In addition, CWL resulted in larger but fewer trees per hectare which may also benefit biodiversity and the recreational use of the stands
Tree growth and ground vegetation 17 years after disc trenching and pre-harvest nitrogen fertilization
Get PDFSilvicultural practices such as site preparation and nitrogen (N) fertilization are commonly used to increase growth of a stand. These practices may affect the forest ecosystem for several decades, impacting not only the trees, but also the stand structure and ground vegetation. Long-term field experiments are thus necessary to study these effects. In our study, two field experiments, Hagfors and Nissafors, established around 1980, were used to study residual effects of previous N-fertilization and disc trenching (DT) on tree growth and ground vegetation 17 years after final felling. At both sites, DT reduced tree mortality and increased individual tree growth, resulting in higher stem numbers and tree volume per hectare after 17 years. Previous N-fertilization had no significant effect on tree growth. The ground vegetation was affected by DT at both sites. At Hagfors, the most pronounced effects were a reduction in the cover of Cladonia rangiferina, and an increase in Calluna vulgaris after DT. Cladonia rangiferina was also negatively affected by previous N-fertilization. At Nissafors, DT caused a shift in cover of Vaccinium vitis-idaea to Vaccinium myrtillus. The impact of DT on the field layer composition appears to have been caused by the soil disturbance but also the increased shading resulting from the increased tree growth and survival. This study indicates that previous N-fertilization and DT affect the ground vegetation in the longer term. This should be considered when developing guidelines and forestry practices
Creep heating in outdoor farrowing huts may increase piglet welfare without impacting survival and growth
Get PDFNewborn piglets are prone to hypothermia, and higher mortalities are suggested in outdoor farrowing huts. Therefore, we investigated whether creep heating during the first 7 days after parturition improves piglet survival and welfare. Data (location, behaviour, weight, mortality) were collected from birth to weaning at 7 weeks from 88 litters across seasons. Each hut contained four pens, half with a heated (HEAT) piglet creep area and half of these had a metal bar ('pendulum') to support the sow's lying-down movement. The position of the sow at birth influenced the first piglet entry to the creep (rump facing creep: median 87 min vs snout facing creep: 191 min after the birth of the first piglet; P = 0.037). During the first day of life (D0), creep usage was low (2.6 +/- 0.65 % of observations) regardless of heating (P = 0.20) and season (P = 0.38; spring: 1.5 %, summer: 2.7 %, autumn: 1.8 %, winter: 3.1 %). Most piglets on D0 were at the udder (71.5 +/- 1.83 %) or in the pen, away from the sow (25.9 +/- 1.87 %). Creep usage increased after D0, with more piglets inside if heated (D2, HEAT: 28.0 +/- 3.16 % vs not: 6.8 +/- 1.85 %;
The Soilborne Fungus Verticillium longisporum and Its Interactions with the Brassicaceous Hosts
Get PDFVerticillium longisporum, a soilborne fungal species, is the causative agent of Verticillium stripe disease in Brassica species and represents a notable threat to agricultural production, particularly in regions where oilseed rape is a major crop, including Europe, North America, and Asia. The microsclerotia of this pathogen can persist in the soil for extended periods, with a potential lifespan of up to a decade, thereby posing a substantial challenge for the complete eradication of the pathogen from infested soil. The genome of V. longisporum is amphidiploid and resulted from the hybridization of V. dahliae (D genotypes) and an unidentified species (A1 genotype). At least three independent hybridization events are estimated to have occurred, resulting in three distinct lineages: A1/D1, A1/D2, and A1/D3. Genome sequence analysis revealed the presence of mating-type idiomorphs, putative cell wall-degrading enzymes, and effectors. However, due to the complexity of the genome, there is a paucity of research on the molecular interactions between V. longisporum and Brassica crops. This review summarizes the extant knowledge regarding the pathogenicity factors that V. longisporum deploys upon infection and the host immune responses against this attack, highlighting aspects that remain to be elucidated and the molecular tools available for studying this interaction. A better understanding of the molecular interactions in this pathosystem will contribute to developing more effective control measures against this disease in Brassica oilseed and cabbage crops.Copyright (c) 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license
Utvärdering av råttskrämma på vild population av råttor
Get PDFDenna studie undersöker effekten av dedikerade ultraljudsignaler (25kHz – 85 kHz) som en icke-dödande metod för att minska råttors aktivitet i en bostadskällare. Ultraljudssignalens toppvärden överstiger 100 dB och täcker det frekvensområde där råttors hörsel är som mest känslig. Signalens tidskarakteristik efterliknar ett varningsljud som råttor själva skapar genom att gnissla tänder. Försöket genomfördes under tre veckor i tre olika utrymmen (rum, korridor och skrubb) i ett flerbostadshus med dokumenterade problem med vilda råttor. Under kontrollveckan registrerades råttaktivitet med IR-kameror utan ljudpåverkan. Under interventionsveckan aktiverades en ljudskrämma som sände ut pulserat ultraljud i form av korta sinussvep. Resultaten visade en signifikant minskning i råttobservationer, särskilt i korridoren där aktiviteten sjönk med över 90 %. Studien tyder på att dedikerade ultraljudssignaler över 100 dB kan fungera som ett effektivt och icke-dödande komplement till traditionell skadedjurskontroll, särskilt i öppna utrymmen med god spridning av ljud
Variations in bacterial profiles associated with semen collection timing and bull breed, analyzed using 16S rRNA sequencing and MALDI-TOF MS
Get PDFIntroduction Bacterial contamination can occur at multiple stages of semen processing, necessitating the use of antibiotics in bull semen preservation, mandated by regulatory guidelines. To manage antimicrobial resistance (AMR), targeted antibiotic use based on bacterial identification is essential. This study aimed to characterize bacterial communities in bull semen using metagenomic analysis and MALDI-TOF MS across different semen collection times from the same bulls and between two breeds.Methods Semen samples were collected from 20 dairy bulls (8 Viking Holstein and 12 Viking Red). Each bull provided three ejaculates within a week: the first after a 96 h since previous collection (T1), the second 48 h later (T2), and the third 24 h after the second (T3). Bacterial species were identified through culturing on cattle blood agar, followed by MALDI-TOF MS identification. Additionally, 16S rRNA sequencing was performed to determine bacterial diversity after DNA extraction.Results MALDI-TOF analysis identified 33 bacterial species across 60 semen samples. Six species were exclusive to Viking Holstein (VH) bulls, while 12 were specific to Viking Red (VR) bulls. Certain bacterial species were present only at specific time points: three in the first ejaculate, seven in the second, and five in the third. Across individual bulls, Bacillus spp., Proteus spp., and Staphylococcus spp. were the most consistently detected. Metagenomic analysis revealed 23 phyla and 402 genera in semen samples. Alpha diversity (Shannon index) showed a trend toward p = 0.07 across the bull samples, while beta diversity significantly differed between breeds, with VH samples forming a distinct cluster and VR samples displaying greater microbiome variability. Additionally, specific genera appeared only at one collection time point: Bacteroides, Serratia, Pantoea at T1, Wolbachia, Prevotella, Peptococcus, Alloprevotella at T2, and Streptococcus, Staphylococcus, and Mycoplasma at T3. Specific genera, Acidocella and Escherichia, exhibited negative correlations with most bacterial taxa but showed a slight positive correlation with each other; while Acidocella was detected in nearly all semen samples, except for two samples.Discussion The seminal microbiota of bulls varies over time and differs between breeds, indicating that it is influenced by a complex interaction of environmental, physiological, and host-related factors
Resultat från Integrerad kustfiskövervakning
No full textI den här rapporten sammanfattas resultat och bedömningar från programmet för integrerad kustfiskövervakning i Torhamn. Ett provfiske för att följa kustfisksamhällets utveckling och fiskhälsoundersökningar har utförts årligen i området sedan 2002. Till skillnad från övriga områden längs den svenska kusten där en integrerad kustfiskövervakning årligen utförs, sker inga undersökningar av miljögiftskoncentrationen i fisken från Torhamn. Syftet med den integrerade kustfiskövervakningen är att kartlägga fiskbeståndens status samt fiskens hälsotillstånd och miljögiftsbelastning för att upptäcka förändringar som indikerar storskalig påverkan av olika miljöhot som eutrofiering, miljögifter, klimatförändringar och andra miljöfaktorer.Resultaten från provfisket i området visar att fångsterna av sill (Clupea harengus), löja (Alburnus alburnus), vimma (Vimba vimba) och skrubbskädda (Platichthys flesus/solemdali) har ökat under den studerade tidsperioden 2002–2024. Fångsterna av rovfiskarna gädda (Esox lucius) och abborre (Perca fluviatilis) minskar däremot och under de senaste åren har ingen gädda fångats i provfisket. Storleken på de stora abborrarna (L90) i området har inte förändrats, men abborrens tillväxt har ökat kraftigt över tid. Det är dock slående att abborren som fångas i provfisket i Torhamn är väldigt ung, och under de senaste åren har få individer äldre än tre år fångats.Den tidigare negativa utvecklingen i abborrens hälsotillstånd i Östersjön tycks generellt ha planat ut under de senaste åren, men aktiviteten hos avgiftningsenzymet EROD ökar hos abborrhanar från området. Även aktiviteterna hos leverenzymen katalas och glutationreduktas ökar hos abborre, vilket tyder på förhöjd oxidativ stress och påverkan från kemiska ämnen. Det finns även tecken på förbättrat hälsotillstånd hos abborren med en minskad andel av vita blodceller samtidigt som det är något oroande med minskningar av guleproteinet vitellogenin i abborrhonornas blod vilket kan indikera en påverkan på reproduktionen
Movement and habitat use of native and non-native small benthic fish in a high conservation value agricultural environment
No full textDespite the considerable progress that has been made in the field of taxonomy and genetics of freshwater fish, there is still a paucity of knowledge regarding their ecology and behaviour. We used PIT-telemetry to study movement and habitat use of native and non-native benthic fish species in a spring fed irrigation stream, subject to seasonal macrophyte removal, in a rice field in North-Western Italy. This anthropogenically managed environment constitutes a habitat of high conservation value for some important endemisms, while hosting several non-native species. Fish were tracked both using manual tracking and stationary PIT-antennas, and telemetry data was complemented with catch data from electrofishing. The native P. bonelli and the non-native M. anguillicaudatus were tracked in sufficient numbers to allow quantitative analysis. While successfully tracked in the study area, both species were mostly stationary, but some fish registered movements in the study area of several hundred meters. M. anguillicaudatus showed a tendency of greater movements. With time, most fish disappeared from the study area, but no direct migratory movement was detected. M. anguillicaudatus showed a clear preference for macrophyte-covered substrates while P. bonelli were frequently tracked both among macrophytes and on gravel substrates. Electrofishing data showed higher fish abundance in reaches subject to only partial macrophyte removal (fish friendly management) compared to those subject to standard removal. Overall, movement seems to be an integral part of the ecology of benthic fish in this system where vegetation appears to structure their spatial behavior
Hybrid Double Enzyme Biocatalyst for Effective Degradation of Organic Pollutants
No full textThis study focuses on the development of environmentally friendly double enzyme catalysts for the degradation of organic pollutants in water, addressing key environmental concerns. The hybrid tandem system of xanthine oxidase (XO) with horseradish peroxidase (HRP) is designed for sustainable water treatment by using a natural and eco-friendly silicate substrate, perlite, as a support for the enzyme cascade reaction. The catalytic process was optimized for environmental applications. XO-generated hydrogen peroxide through the oxidation of hypoxanthine, which then activated HRP to break down a variety of harmful pollutants, including industrial dyes, pharmaceuticals, and phenolic compounds. The system demonstrated high pollutant removal efficiency, reaching up to 100% in some cases, while maintaining catalytic stability across a range of temperatures and pH values. Importantly, the biocatalytic system addressed secondary pollution-a common issue in conventional treatments. Thus, uric acid, a potential byproduct of the XO catalytic action, was degraded by HRP, preventing the accumulation of harmful byproducts in purified water. This research highlights the potential of the tandem XO-HRP enzyme cascade as a green, efficient, and sustainable solution for water purification, offering an environmentally responsible alternative to traditional methods that often contribute to further contamination