| 1. |
- Eriander, Louise, 1984, et al.
(författare)
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The effects of small-scale coastal development on the eelgrass (Zostera marina L.) distribution along the Swedish west coast – Ecological impact and legal challenges
- 2017
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Ingår i: Ocean and Coastal Management. - : Elsevier BV. - 0964-5691. ; 148, s. 182-194
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Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic impacts on coastal areas have led to an increased degradation of marine environments globally. Eelgrass ecosystems are particularly susceptible to human induced stressors as they are sensitive to low light conditions and usually grow in shallow protected areas where pressure from coastal development is high. The extensive decline in coverage of eelgrass along the Swedish Northwest coast since the 1980s has largely been attributed to the effects of coastal eutrophication and overfishing. However, the impact on eelgrass from small-scale coastal development (docks and marinas) has never been investigated in this area. The aim of this study was to assess the local and large-scale effect of shading by docks and marinas on eelgrass habitats along the Swedish NW coast and to investigate the decision process behind small-scale exploitation to identify problems with the current legislation, which allows for continued exploitation of eelgrass. Through field assessments of eelgrass around docks and analysis of available data on eelgrass and dock distribution along the coast, the present study demonstrates that shading from docks reduced eelgrass coverage with on average 42e64% under and adjacent to the docks, and that floating docks affected larger areas and caused a much stronger reduction in eelgrass coverage (up to 100% loss) compared to docks elevated on poles (up to 70% reduction in coverage). The total eelgrass area negatively affected by docks and marinas along the NW coast was estimated to approximately 480 ha, an area corresponding to over 7% of the present areal coverage of eelgrass in the region. The analysis of decisions for dock construction showed that eelgrass was generally not assessed or considered in the decision process and that 69e88% of the applications were approved also in areas where eelgrass was present. Furthermore, marine protected areas only marginally reduced the approval of applications in eelgrass habitats. The continued small-scale development along the Swedish NW coast constitutes a significant threat to the already decimated coverage of eelgrass along the coast and changes in the management practices are needed in order to achieve both national and international goals on environmental status.
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| 2. |
- Bergström, Per, 1980, et al.
(författare)
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Biodeposits from Mytilus edulis: a potentially high-quality food source for the polychaete, Hediste diversicolor
- 2019
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Ingår i: Aquaculture International. - : Springer Science and Business Media LLC. - 0967-6120 .- 1573-143X. ; 27, s. 89-104
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Tidskriftsartikel (refereegranskat)abstract
- Previous studies have shown clearly that the deposit feeding polychaete, Hediste diversicolor, can promote oxygenation of sediments exposed to excess loads of mussel faeces. In this experimental study, we explicitly test their utility as food for H. diversicolor to survive and grow on. Furthermore, in order to understand the consequences of experimental manipulations, we also evaluated effects on chemical fluxes in and out of the sediment. The results show strong differences in growth but no difference in short-term survival. Fed only on mussel faeces, the polychaetes grew on average 17% in wet weight after a period of 10days, compared to 3% when given equivalent amounts of organic matter from the natural sediments. Addition of faeces to natural sediments resulted in 19–20% growth, thus suggesting an approximate additive effect of the two food sources. Chemical analyses showed that, oxygen consumption increased with load of organic material irrespective of origin, faecal material caused higher fluxes of ammonia compared to natural organic material, but neither oxygen consumption nor nutrient fluxes were affected by the ashing of sediments. In contrast, fluxes of silicate increased as a consequence of ashing but were not affected by the addition of mussel faeces. Thus, despite risks of experimental artefacts due to ashing of sediments, the results show that oxygen and nutrient dynamics responded to manipulations of organic material and not to the potential modification of sediment structure. Therefore, the observed effects on growth of H. diversicolor can be safely interpreted as caused by differences in amount and quality of organic material. Mussel faeces is a high-quality food source for this species of polychaete and, in combination with ample evidence from previous studies that bioturbation, we conclude that H. diversicolor is a suitable candidate in further efforts to develop technical solutions based on bioturbation for mitigation of adverse effects on benthic environments in connection with mussel-farming.
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| 3. |
- Bergström, Per, 1980, et al.
(författare)
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Environmental influence on mussel (Mytilus edulis) growth - A quantile regression approach
- 2016
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Ingår i: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714 .- 1096-0015. ; 171, s. 123-132
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Tidskriftsartikel (refereegranskat)abstract
- The need for methods for sustainable management and use of coastal ecosystems has increased in the last century. A key aspect for obtaining ecologically and economically sustainable aquaculture in threatened coastal areas is the requirement of geographic information of growth and potential production capacity. Growth varies over time and space and depends on a complex pattern of interactions between the bivalve and a diverse range of environmental factors (e.g. temperature, salinity, food availability). Understanding these processes and modelling the environmental control of bivalve growth has been central in aquaculture. In contrast to the most conventional modelling techniques, quantile regression can handle cases where not all factors are measured and provide the possibility to estimate the effect at different levels of the response distribution and give therefore a more complete picture of the relationship between environmental factors and biological response. Observation of the relationships between environmental factors and growth of the bivalve Mytilus edulis revealed relationships that varied both among level of growth rate and within the range of environmental variables along the Swedish west coast. The strongest patterns were found for water oxygen concentration level which had a negative effect on growth for all oxygen levels and growth levels. However, these patterns coincided with differences in growth among periods and very little of the remaining variability within periods could be explained indicating that interactive processes masked the importance of the individual variables. By using quantile regression and local regression (LOESS) this study was able to provide valuable information on environmental factors influencing the growth of M. edulis and important insight for the development of ecosystem based management tools of aquaculture activities, its use in mitigation efforts and successful management of human use of coastal areas. © 2016 Elsevier Ltd.
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| 4. |
- Bergström, Per, 1980, et al.
(författare)
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Modeling and predicting the growth of the mussel, Mytilus edulis: implications for planning of aquaculture and eutrophication mitigation
- 2015
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 5:24, s. 5920-5933
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Tidskriftsartikel (refereegranskat)abstract
- The increased pressure on the marine ecosystems highlights the need for policies and integrated approaches for sustainable management of coastal areas. Spatial planning based on geographic information of human activities, ecological structures and functions, and their associated goods and services is a fundamental component in this context. Here, we evaluate the potential of predictive modeling to provide spatial data on one ecosystem function, mussel growth for use in such processes. We developed a methodology based on statistical modeling, spatial prediction, and mapping for the relative growth of the blue mussel, Mytilus edulis. We evaluated the performance of different modeling techniques and classification schemes using empirical measurements of growth from 144 sampling sites and data on biological, chemical, and physical predictors. Following comparisons of the different techniques and schemes, we developed random forest models to predict growth along the Swedish west coast. Implemented into GIS the best model produced in this study predicts that low, intermediate, and high growth rates can be expected in 53%, 32%, and 15% of modeled area, respectively. The results of this study also suggest that the nature and quality of predictor data hold the key to improving the predictive power of models. On a more general note, this study exemplifies a feasible approach based on measuring, modeling, and mapping for obtaining scientifically based spatial information on ecosystem functions and services affected by a complex set of factors. Such information is fundamental for maritime spatial planning and ecosystem-based management and its importance is likely to increase in the future. Because of its close link to nutrient assimilation and production yield, site-specific information of soft tissue growth such as the map of predicted growth rate developed in this study can be used as a tool for optimizing actions aimed at mitigating eutrophication and aquaculture operations and in maritime spatial planning processes of coastal areas.
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| 5. |
- Bergström, Per, 1980, et al.
(författare)
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Testing the potential for improving quality of sediments impacted by mussel farms using bioturbating polychaete worms
- 2017
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Ingår i: Aquaculture Research. - : Hindawi Limited. - 1365-2109 .- 1355-557X. ; 48:1, s. 161-176
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Tidskriftsartikel (refereegranskat)abstract
- Biodeposits from farmed mussels severely influence the biogeochemistry of sediments by increasing the levels of organic matter (OM). Mitigation of such negative impacts is important for the development of sustainable aquaculture operations. As a step towards developing methods for remediation of coastal sediments affected by mussel farming, the effects of the polychaete, Hediste diversicolor was evaluated experimentally. In a series of field- and laboratory experiments we tested hypotheses about the effects of polychaetes on sediment oxygen consumption, nutrient fluxes and sulphide pools under different polychaete densities and sedimentation regimes. The experimental results support the idea that polychaetes can mitigate negative effects on the benthic environment beneath mussel farms. H.diversicolor oxidized the sediment and generally enhanced the oxygen consumption, and thus the decomposition of OM. The accumulation of pore water sulphides were reduced and fluxes of nutrients across the sediment-water interface increased. Additional calculations suggest that the effects of polychaetes were mainly indirect and driven by increased microbial activity due to the borrowing activity of the polychaetes. Trends of increasing decomposition with increasing polychaete density suggest that the decomposition could be further enhanced by higher densities. Overall, we concluded that H.diversicolor is a potentially strong candidate for remediation of mussel farm sediments. The results show that sediments inhabited by H.diversicolor have high assimilative capacity of OM and oxygen conditions are significantly improved following the addition of polychaetes at naturally occurring densities. However, technological developments are needed in order to allow the approach to be used in practice.
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| 6. |
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| 7. |
- KC, Ashish, 1982-, et al.
(författare)
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Scaling up quality improvement intervention for perinatal care in Nepal (NePeriQIP); study protocol of a cluster randomised trial
- 2017
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Ingår i: BMJ Global Health. - : BMJ. - 2059-7908. ; 2:3
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Nepal Perinatal Quality Improvement Project (NePeriQIP) intends to scale up a quality improvement (QI) intervention for perinatal care according to WHO/National guidelines in hospitals of Nepal using the existing health system structures. The intervention builds on previous research on the implementation of Helping Babies Breathe-quality improvement cycle in a tertiary healthcare setting in Nepal. The objective of this study is to evaluate the effect of this scaled-up intervention on perinatal health outcomes.METHODS/DESIGN: Cluster-randomised controlled trial using a stepped wedged design with 3 months delay between wedges will be conducted in 12 public hospitals with a total annual delivery rate of 60 000. Each wedge will consist of 3 hospitals. Impact will be evaluated on intrapartum-related mortality (primary outcome), overall neonatal mortality and morbidity and health worker's performance on neonatal care (secondary outcomes). A process evaluation and a cost-effectiveness analysis will be performed to understand the functionality of the intervention and to further guide health system investments will also be performed.DISCUSSION: In contexts where resources are limited, there is a need to find scalable and sustainable implementation strategies for improved care delivery. The proposed study will add to the scarce evidence base on how to scale up interventions within existing health systems. If successful, the NePeriQIP model can provide a replicable solution in similar settings where support and investment from the health system is poor, and national governments have made a global pledge to reduce perinatal mortality.TRIAL REGISTRATION NUMBER: ISRCTN30829654.
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| 8. |
- Koh, Ara, et al.
(författare)
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Microbially Produced Imidazole Propionate Impairs Insulin Signaling through mTORC1
- 2018
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Ingår i: Cell. - : Elsevier BV. - 0092-8674. ; 175:4
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Tidskriftsartikel (refereegranskat)abstract
- Interactions between the gut microbiota, diet, and the host potentially contribute to the development of metabolic diseases. Here, we identify imidazole propionate as a microbially produced histidine-derived metabolite that is present at higher concentrations in subjects with versus without type 2 diabetes. We show that imidazole propionate is produced from histidine in a gut simulator at higher concentrations when using fecal microbiota from subjects with versus without type 2 diabetes and that it impairs glucose tolerance when administered to mice. We further show that imidazole propionate impairs insulin signaling at the level of insulin receptor substrate through the activation of p38 gamma MAPK, which promotes p62 phosphorylation and, subsequently, activation of mechanistic target of rapamycin complex 1 (mTORC1). We also demonstrate increased activation of p62 and mTORC1 in liver from subjects with type 2 diabetes. Our findings indicate that the microbial metabolite imidazole propionate may contribute to the pathogenesis of type 2 diabetes.
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| 9. |
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| 10. |
- Moksnes, Per-Olav, et al.
(författare)
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Fritidsbåtars påverkan på grunda kustekosystem i sverige
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sveriges natursköna kust med vidsträckta skärgårdar erbjuder fantastiska förhållanden för fritidsbåtliv. Idag finns uppskattningsvis mer än 700 000 fritidsbåtar i Sverige, vilket är en av de högsta siffrorna i världen sett till befolkningsmängden. Kustens vågskyddade skärgård ger också goda förutsättningar att förvara fritidsbåtar vid bryggor, och idag täcks stora områden av bryggor och småbåtshamnar. Det stora antalet båtar och bryggor kan ge betydande effekter på miljön, men kunskapen om fritidsbåtlivets sammanlagda påverkan på Sveriges kustmiljöer har hittills varit bristfällig. Havsmiljöinstitutets mål med denna rapport har varit att sammanställa kunskapsläget kring hur fritidsbåtar påverkar grunda kustekosystem i Sverige, samt bedöma omfattningen av denna påverkan och om utveckling är hållbar. Syftet med rapporten är att bidra till utvecklingen av en mer hållbar förvaltning av fritidsbåtlivet genom att sammanställa vetenskaplig kunskap inom detta område på ett lättillgängligt sätt. Sammanställningen visar att det finns ett starkt stöd i den vetenskapliga litteraturen för att fritidsbåtar ger upphov till många negativa effekter på kustmiljön. Med fritidsbåtslivet följer en rad olika fysiska strukturer och aktiviteter som var och en ger upphov till flera olika typer av miljöpåverkan. En ökad utbredning av småbåtshamnar, bryggor och muddrade områden medför förluster av viktiga bottenmiljöer och leder ofta till en långvarig försämring av miljöförhållanden lokalt. Muddrings- och dumpningsaktiviteter leder till ökad uppgrumling och spridning av sediment, näringsämnen och miljögifter över stora områden, vilket bland annat påverkar bottenvegetation, fiskar och musslor negativt. Båttrafik och ankring leder till uppgrumling och erosion av sediment samt till skador på bottenmiljön. Undervattensbuller från båtarnas motorer stör också fiskar och däggdjur. Vidare medför användning av fritidsbåtar betydande utsläpp av giftiga ämnen och föroreningar från båtbottenfärger och förbränningsmotorer. Drygt 60 % av alla bryggor och småbåtshamnar återfinns i grunda (<3 m), vågskyddade områden med mjukbottnar, trots att de endast utgör en fjärdedel av kustens totala grundområden. Dessa områden lämpar sig väl för båtförvaring, men är också en av kustens mest produktiva och värdefulla miljöer. Grunda mjukbottnar är en viktig miljö för olika kärlväxter och kransalger, som i sin tur utgör viktiga uppväxthabitat för många olika fiskarter och kräftdjur. Rapporten visar att dessa miljöer är extra känsliga för en majoritet av de störningar som fritidsbåtlivet ger upphov till. Sammantaget medför detta att fritidsbåtslivet i förhållande till sin omfattning genererar stora skador på miljöer med höga naturvärden.
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| 11. |
- Thorngren, Linnea, et al.
(författare)
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Assessment of the population of Ostrea edulis in Sweden: A marginal population of significance?
- 2019
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758.
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Tidskriftsartikel (refereegranskat)abstract
- The European flat oyster Ostrea edulis is an economically and ecologically important species subjected to extensive protection and restoration efforts, due to sharp population declines in Europe. In Sweden, O. edulis occurs at the northern fringe of its range. Knowledge of the distribution and abundance of the species is limited, and the size of the population has never been estimated. Oyster fishery sustainability has never been assessed. Using a random sampling approach and towed video, we collected data on oyster occurrence at 435 sites to estimate abundance and distribution of O. edulis in the Swedish Skagerrak region. Furthermore, the size of the population was assessed and the current management and legislation strategy of the species was analyzed. Living O. edulis was found in 27% of all sampled sites above 6 m, and the size of the population was estimated to 36.6 +/- 16.3 million individuals (total population +/- SE). The distribution was patchy, and approximately 60% of the population was found in oyster bed densities (>= 5 oysters/m(2)), which corresponds to around 1% of the sampled sites. The nondestructive sampling method and representative design provided useful estimates of population size and error, which indicate that the marginal population of O. edulis in Sweden constitutes a significant part of the remaining European population. We argue that the relatively good status of the Swedish population can be explained by (a) private ownership of fishing rights, (b) a small-scale fishery that exploits <0.5% of the estimated population annually, conducted using nondestructive methods, and (c) parasite-free waters, potentially due to effective prevention of spread of infection. Open Research Badges This article has earned an Open Data Badge for making publicly available the digitally-shareable data necessary to reproduce the reported results. The data is available at .
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