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Using fuzzy cognitive mapping to assess the sustainability impacts of transitioning to pasture-fed production in the UK beef sector
Get PDFOne hundred percent pasture-fed beef production has been suggested as a promising approach for sustainable ruminant farming, due to the potential benefits that can accrue across a range of sustainability domains. This study aimed to investigate the impacts across the four domains of sustainability of a wholesale switch from conventional to 100% pasture-fed beef production in the UK. We used fuzzy cognitive mapping (FCM) as a method for extracting knowledge from multiple stakeholders to create representative systems models of both conventional and pasture-based beef production systems. We then conducted a scenario analysis to assess how a switch to a pasture-fed system could affect components of sustainability in the UK beef sector. The FCMs indicated that vegetation quality, grass use efficiency, and soil health were central components of the pasture-fed approach, while economic and regulatory aspects, and climate change targets were more central to mainstream production approaches. The most marked changes under the 100% conversion scenario were an increase in income from subsidies (27.3%) in line with 'public money for public goods', a decrease in ability to export beef (unless advice to reduce consumption of animal protein is followed) (23.5%), a decrease in land used for farming vs other uses (e.g., natural capital) (11.23%), and a decrease in the use of feed from agricultural co/byproducts (7.5%), freeing up these feed sources for more sustainable monogastric production. Therefore, the mapping and scenario analysis suggests that while upscaling the pasture-fed approach may reduce productivity, it would likely increase public goods provision and reduce feed-food competition in the UK
Towards sustainable onion storage
Get PDFOnion is an important component of the diets of many cultures worldwide, and also one of the most commonly produced vegetables. The onion bulb is a well-adapted storage organ and many of the harvested bulbs are stored for several months to ensure year-round availability to consumers. However, significant amounts are lost due to sprouting, loss of water, loss of dry matter, fungal infections and bacterial infections. To optimise storage and enable sales at the correct point in time to reduce losses decision support systems are needed to identify signs of quality problems. One potential such system is the monitoring of volatile organic compounds in the air of storage facilities to detect developing quality problems, such as storage diseases. In this thesis, the volatile organic compounds emanating into the headspace of onion bulbs affected by Fusarium basal plate rot, Penicillium rot or Pectobacterium-caused soft rot were investigated. The aim was to identify the compounds that are relevant as indicators of developing storage diseases, and which could be the target of future monitoring systems. Several relevant indicator compounds were found. Some of them are naturally occurring onion metabolites whose relative abundance changed, including methyl propyl disulfide and dimethyl disulfide. Others, such as ethenylbenzene and 2,3-butanediol are products typical of fungal or bacterial metabolism. Other systems for storage monitoring may include physiological measurements to predict quality changes such as sprouting. Therefore, the thesis also investigated the connection between selected physiological indicators and sprouting. It was found that the changing concentrations of glucose, fructose and sucrose, and the decreasing dry matter contents of the bulbs had a significant connection to the start of sprouting
Nätprovfisket i Vänern 2024
Get PDFSötvattenslaboratoriet vid institutionen för akvatiska resurser, SLU Aqua, genomförde sommaren 2024 ett nätprovfiske i Vänern. Provfisket är en del av övervakningsprogrammet för Hjälmaren, Mälaren, Vänern och Vättern, som SLU Aqua utför och är datavärd för. Provfisket utfördes mellan 2024-07-11 och 2024-08-01 som ett djupstratifierat provfiske med BKust 9+2 nät på de grundare områdena och med Bss-nät på de djupare områdena. De lokaler som provfiskades inom det ordinarie övervakningsprogrammet var Spårön-Rackeby skärgård, Fågelö-Torsö, Byviken och Ölmeviken. Även Sätterholmsfjärden provfiskades men då den inte ingår i övervakningsprogrammet redovisas inte resultaten i denna rapport. Totalt fångades 24 arter i provfisket varav abborre och mört var de dominerande arterna sett till både antal och vikt på grundare områden (BKust 9+2 nät). På de djupare områden som provfiskas med Bss nät var abborre och sik de dominerande arterna sett till både antal och vikt. Fångstutvecklingen analyserades för förändringar över tid med avseende på antalet fångade individer och deras längdfördelningar. Mellan 2009 och 2024 har antal per ansträngning av abborre och braxen ökat. Under samma period har vikt per ansträngning ökat av abborre och stor sik. Lakens och sikens längd har ökat
New Insights into the Composition of Aggregation Pheromones in Polygraphus poligraphus, Polygraphus punctifrons, Polygraphus subopacus and Polygraphus proximus
Get PDFFour-eyed bark beetles of the genus Polygraphus have been involved in large bark beetle outbreaks in different parts of the world, resulting in major economic losses. A striking example is the invasive species Polygraphus proximus which is a pest on Abies sibirica in Russia. In Sweden, Polygraphus poligraphus has been involved in bark beetle outbreaks on Norway spruce, Picea abies, together with the European spruce bark beetle Ips typographus. Two related species, Polygraphus punctifrons and Polygraphus subopacus are also present in Sweden. Recently, aggregation pheromones or pheromone components have been identified for these four Polygraphus species. However, questions remain regarding the complete composition of their pheromones, particularly for P. subopacus and P. proximus, whose aggregation pheromones appear to be very similar. In an attempt to better understand the chemical communication of these species, additional studies were conducted on P. poligraphus, P. punctifrons and P. subopacus using solid phase microextraction coupled with gas chromatography and mass spectrometry (SPME-GC-MS), electroantennography (EAG) as well as SPME-GC-MS and GC-MS with electroantennographic detection (EAD). Field experiments were also conducted. In P. punctifrons, some male-specific compounds were found in addition to those previously identified. In EAG and SPME-GC-MS/EAD studies, all three Polygraphus species responded strongly to grandisol. Using a chiral column, GC-MS/EAD revealed that they were able to detect both enantiomers of grandisol. In summary, this work presents our current understanding of the aggregation pheromones in four Polygraphus species and the challenges we have met in identifying species-specific pheromone blends for some of these species
Review and Prospects of Phytoremediation: Harnessing Biofuel-Producing Plants for Environmental Remediation
Get PDFHeavy metal (HM) pollution has become a major environmental concern due to increased anthropogenic activities. The persistence and toxicity of HMs pose significant risks to ecosystems, biodiversity, and human health. This review highlights the pressing issue of HM contamination, its impact on ecosystems, and the potential risks of bio-magnification. Addressing these issues requires sustainable and cost-effective solutions. Among various remediation strategies, phytoremediation stands out as a promising green technology for mitigating environmental damage by using plants to extract or detoxify contaminants. A key challenge in phytoremediation, however, is the management of large volumes of contaminated biomass. This study explores the integration of phytoremediation with biofuel production, which not only addresses biomass management but also offers a sustainable solution within the framework of the circular economy. The dual role of specific plant species in both phytoremediation and biofuel production is evaluated, providing reduced environmental waste, lowering remediation costs, and promoting energy security. Future advancements in plant engineering, biotechnology, and process optimization hold the potential to enhance phytoremediation efficiency and biofuel yields. Expanding research into metal-tolerant, high-biomass crops can further improve scalability and economic feasibility. The review also critically assesses challenges such as the safe handling of contaminated biomass, sustainability concerns, and existing research gaps. By merging environmental remediation with bioenergy production, this interdisciplinary approach presents a viable pathway toward sustainable development
Deep phenotyping platform for microscopic plant-pathogen interactions
Get PDFThe increasing availability of genetic and genomic resources has underscored the need for automated microscopic phenotyping in plant-pathogen interactions to identify genes involved in disease resistance. Building on accumulated experience and leveraging automated microscopy and software, we developed BluVision Micro, a modular, machine learning-aided system designed for high-throughput microscopic phenotyping. This system is adaptable to various image data types and extendable with modules for additional phenotypes and pathogens. BluVision Micro was applied to screen 196 genetically diverse barley genotypes for interactions with powdery mildew fungi, delivering accurate, sensitive, and reproducible results. This enabled the identification of novel genetic loci and marker-trait associations in the barley genome. The system also facilitated high-throughput studies of labor-intensive phenotypes, such as precise colony area measurement. Additionally, BluVision's open-source software supports the development of specific modules for various microscopic phenotypes, including high-throughput transfection assays for disease resistance-related genes
Development of mesoporous silica-based active coatings for methylmercury removal: Towards enhanced active packaging
Get PDFActive coatings capable of selectively removing pollutants are an innovative approach against human exposure to pollutants via food. This study aimed to develop an active coating capable of removing methylmercury from liquid food media. Thiolation of mesoporous silica particles modified via (3-Mercaptopropyl)trimethoxysilane increased their mercury adsorption capacity to 100 mg/g. The particles were successfully integrated into industrial, epoxy and polyurethane coatings but the induced mercury adsorption efficiency in the coatings was dependent on their type of binder. Scanning electron microscopy and energy-dispersive X-ray results revealed that the silica particles were entrapped within the coatings but remained more accessible to the external media in the industrial and polyurethane coatings. Thermogravimetric analysis confirmed the successful integration of the components. The kinetics of adsorption showed that the adsorption of methylmercury was achieved within a time range of 20-240 min, depending on the binder used in the coating. The methylmercury adsorption ability of the coatings was preserved in different food simulants and in the presence of competitive ions and in an environment comprising cysteine. In vitro biosafety assays on different cell lines showed no negative effect from the silica modification on the safety of the coatings
Spatio-temporal dynamics and controls of forest-floor evapotranspiration across a managed boreal forest landscape
Get PDFForest-floor evapotranspiration (ETff) is a major pathway for water loss in terrestrial ecosystems, often accounting for more than half of ecosystem evapotranspiration. However, our understanding of the environmental and stand structural controls on the spatio-temporal dynamics of ETff across the managed boreal forest landscape remains limited. In this study, we conducted chamber-based flux measurements of ETff and its components, i.e., soil evaporation (Es) and forest-floor understory transpiration (Tu), on natural and vegetation removal plots across 50 diverse forest stands (ranging 5-211 years old) in Northern Sweden over two contrasting growing seasons. We found manifold variations in the growing season means of ETff, Es, and Tu, ranging from 0.008 to 0.048 mm h- 1, 0.004 to 0.034 mm h- 1, and 0.002 to 0.030 mm h- 1, respectively, across the 50 forest stands. The contribution of Es and Tu to ETff ranged from 19 to 83 % and 38 to 85 %, respectively, with the average Es:Tu ratio shifting from 0.84 in 2017 to 0.63 during 2018, the latter experiencing an exceptional summer drought. Seasonal variations in ETff and its component fluxes were mainly controlled by below-canopy air temperature, while radiation was the main driver of their spatial variations across the forest stands. At the landscape-level, stand age was the dominant control of ETff by modifying overstory tree characteristics such as biomass and leaf area index. In contrast, neither tree species nor soil type had any effect on ETff or Tu. However, Es was higher in sediment compared to till soils. Thus, our results suggest that environmental and stand structural factors jointly control the spatio-temporal dynamics of ETff across the managed boreal forest landscape. Our study furthermore highlights the need for an in-depth understanding of ETff and its components when assessing the water cycle feedbacks of the boreal forest to changes in forest management and climate
Exploring the Genetic Regulation of Ability and Quality of Gaits in Icelandic Horses
Get PDFThe Icelandic horse is celebrated for its unique gaits and versatility as a riding horse, yet the genetic basis of these characteristics is not fully understood. Its diverse gait range, the availability of extensive phenotypic records, and the application of advanced genomic technologies make the Icelandic horse an invaluable model for exploring the genetic foundations of gait traits and performance.This thesis aimed to identify novel genetic factors affecting gaits and performance in the Icelandic horse by integrating genomic approaches to analyse genetic variation through genome-wide patterns of homozygosity and polymorphic variation. The study utilized high-density SNP genotype data, generated using a 670k genotype array, from 380 horses to perform genome-wide association (GWA) studies and runs of homozygosity (ROH) analyses. Additionally, 39 horses were included for whole-genome sequencing (WGS) analysis.Through GWA studies, quantitative trait loci (QTLs) affecting gait traits were identified. One QTL was associated with breeding scores for back and croup conformation, which significantly influenced the quality of the lateral gaits tölt and pace. Two additional QTLs were directly linked to breeding scores for pace. Haplotype analysis revealed two frequent haplotypes for each identified QTL that had significant effects on the associated trait. The haplotypes associated with back and croup harboured genes with known roles in muscle and skeletal development in humans. The haplotypes affecting pace scores were located within the candidate genes STAU2 and RELN which are expressed in neural tissue. In addition to the observed effects on pace, the STAU2 haplotypes were found to significantly influence the quality of trot and gallop, while the RELN haplotypes impacted the quality of tölt, trot, canter, and gallop, and may potentially also influence the trainability and precocity of young horses. Moreover, interactions between STAU2, RELN, and the previously identified DMRT3 gene were observed, involving both additive and compensatory effects. Sequence analysis in these regions revealed a partial loss of the STAU2 protein caused by a one-base-pair frameshift insertion. This variant was proposed to be causative for the observed effects of the STAU2 haplotypes. In the RELN region, potential regulatory elements were identified and suggested as candidate variants influencing the effects of the RELN haplotypes.The enduring significance of the genomic region on ECA23, harbouring the DMRT3 gene, was confirmed through ROH analysis, while additional regions of potential relevance to performance traits were identified. Analyses of genomic inbreeding and genetic diversity indicated that recent breeding practices in the Icelandic horse breed have been sustainable, maintaining adequate genetic diversity.In conclusion, this thesis expands current knowledge of the genetic basis of gait and performance in the Icelandic horse, by demonstrating that genetic factors beyond DMRT3 contribute to the regulation of gait ability and quality. The findings warrant further investigations and may ultimately benefit the breeding of the Icelandic horse and assist breeders in making more informed breeding decisions
Modelling PFAS transport in Lake Ekoln: Implications for drinking water safety in the stockholm region
Get PDFPer- and polyfluoroalkyl substances (PFAS) are found frequently in both groundwater and surface water sources across Sweden posing challenges to drinking water supply. Lake Ekoln is located south of Uppsala and is the basin of Lake Mälaren; Lake Mälaren is the third largest lake in Sweden and is the drinking water source for more than two million people. The aim of this study was to simulate the fate and transport of PFAS in Lake Ekoln during the period 2017–2020 using three-dimensional hydrodynamic modelling. The simulated water temperatures were in agreement with the observed water temperatures. The simulated PFAS concentrations were generally in agreement with the available measurements, but the lack of measurements made the comparison uncertain. The modelling results described the seasonal variations of PFAS in Lake Ekoln informing the operation of the drinking water treatment plants located downstream. The modelling results confirmed that the main inflow to the lake – the river Fyrisån – is the main source of PFAS to Lake Ekoln, highlighting the importance of mitigating this source in the context of ensuring safe drinking water supply in the Stockholm region. Regular monitoring of PFAS in the river Fyrisån is needed, and additional measurements in Lake Ekoln would facilitate further model development