1. |
- Kotta, Jonne, et al.
(author)
-
Cleaning up seas using blue growth initiatives: Mussel farming for eutrophication control in the Baltic Sea
- 2020
-
In: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 709
-
Journal article (peer-reviewed)abstract
- © 2019 The Authors Eutrophication is a serious threat to aquatic ecosystems globally with pronounced negative effects in the Baltic and other semi-enclosed estuaries and regional seas, where algal growth associated with excess nutrients causes widespread oxygen free “dead zones” and other threats to sustainability. Decades of policy initiatives to reduce external (land-based and atmospheric) nutrient loads have so far failed to control Baltic Sea eutrophication, which is compounded by significant internal release of legacy phosphorus (P) and biological nitrogen (N) fixation. Farming and harvesting of the native mussel species (Mytilus edulis/trossulus) is a promising internal measure for eutrophication control in the brackish Baltic Sea. Mussels from the more saline outer Baltic had higher N and P content than those from either the inner or central Baltic. Despite their relatively low nutrient content, harvesting farmed mussels from the central Baltic can be a cost-effective complement to land-based measures needed to reach eutrophication status targets and is an important contributor to circularity. Cost effectiveness of nutrient removal is more dependent on farm type than mussel nutrient content, suggesting the need for additional development of farm technology. Furthermore, current regulations are not sufficiently conducive to implementation of internal measures, and may constitute a bottleneck for reaching eutrophication status targets in the Baltic Sea and elsewhere.
|
|
2. |
|
|
3. |
- Nyström Sandman, Antonia, et al.
(author)
-
Grön infrastruktur i havet : landskapsperspektiv i förvaltningen av Sveriges marina områden
- 2020
-
Reports (other academic/artistic)abstract
- En kartläggning av havets naturkvaliteter har påbörjats genom arbetet med grön infrastruktur. Rapporten undersöker olika scenarier för hur den marina gröna infrastrukturen påverkas av mänskliga aktiviteter i förhållande till olika strategier för förvaltning. Projektet har genomfört tre fallstudier med olika fokus: strandexploatering, trålfiske och klimatförändring. Genom scenariobaserade analyser visar forskarna vilken effekt olika beslut och åtgärder kan få på naturskydds- och miljömål.Det tvärvetenskapliga projektet är ett samarbete mellan experter inom ekologi och juridik. Forskarna beskriver hur lagstiftning, planering och förvaltningsstrategier bör utformas och fungera ihop, och presenterar förslag för att stärka skyddet av den gröna infrastrukturen i Sveriges havsområden.Forskningen har finansierats av Naturvårdsverkets miljöforskningsanslag till stöd för Naturvårdsverket och Havs- och vattenmyndighetens verksamhet.
|
|
4. |
- Polovodova Asteman, Irina, 1980, et al.
(author)
-
Spreading of an alien benthic foraminifer in the North Sea: a reason to be worried?
- 2023
-
In: International Congress FORAMS2023, Perugia, Italy, 25-30th June. - Perugia, Italy : Micropress Europe & The Grzybowski Foundation.
-
Conference paper (other academic/artistic)abstract
- In the Skagerrak-Kattegat (eastern North Sea), the alien benthic foraminifer Nonionella sp. T1 (previously referred to as “Nonionella stella”) was reported for the first time in 2011 and 2012 in the Swedish and southern Norwegian fjords, respectively. Based on dated sediment cores its first occurrence can be traced back to the 1980s in the Gullmar Fjord, to the 2000s in the Öresund and to 2010 in the Oslofjord. Since then, Nonionella sp T1 has spread all over the Kattegat and coastal Skagerrak, according to sampling campaigns performed between 2016 and 2022. The species is now highly abundant in the entire Kattegat, including the Öresund, as well as in fjord mouths of the seasonally hypoxic Gullmar Fjord, the oxic Hakefjord and the long-term polluted Idefjord as demonstrated by molecular and morphospecies data. At the same time, Nonionella sp T1 is rare to absent in the Baltic Sea, Skagerrak deep basin and in deep fjords of western and northern Norway. This study shows some preliminary results on the species’ present distribution in the study area and raises questions about the driving factors and potential effects on the local biodiversity.
|
|
5. |
- Eriander, Louise, 1984, et al.
(author)
-
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
-
In: Ocean and Coastal Management. - : Elsevier BV. - 0964-5691. ; 148, s. 182-194
-
Journal article (peer-reviewed)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.
|
|
6. |
- Andersson, Gerhard, 1966-, et al.
(author)
-
Development of a new approach to guided self-help via the Internet : The Swedish experience
- 2008
-
In: Journal of technology in human services. - : Informa UK Limited. - 1522-8835 .- 1522-8991. ; 26:2-4, s. 161-181
-
Journal article (peer-reviewed)abstract
- This article describes the development and empirical status of guided Internet-delivered self-help. The treatment approach combines the benefits of bibliotherapy with book-length text materials and the support given online via web pages and e-mail. Interactive features such as online registrations, tests, and online discussion forums are also included. Cognitive behavior therapy (CBT) guided the research and clinical implementations of this approach, as it lends itself more easily to the self-help format compared with other presently available psychotherapy approaches. We include an overview of the research, current issues and research in service delivery, lessons learned through a program of research, and directions for future investigations
|
|
7. |
- Anton, Victor, et al.
(author)
-
An open-source, citizen science and machine learning approach to analyse subsea movies
- 2021
-
In: Biodiversity Data Journal. - 1314-2828. ; 9
-
Journal article (peer-reviewed)abstract
- Background The increasing access to autonomously-operated technologies offer vast opportunities to sample large volumes of biological data. However, these technologies also impose novel demands on ecologists who need to apply tools for data management and processing that= are efficient, publicly available and easy to use. Such tools are starting to be developed for wider community and here we present an approach to combine essential analytical functions for analysing large volumes of image data in marine ecological research. New information This paper describes the Koster Seafloor Observatory, an open-source approach to analysing large amounts of subsea movie data for marine ecological research. The approach incorporates three distinct modules to: manage and archive the subsea movies, involve citizen scientists to accurately classify the footage and, finally, train and test machine learning algorithms for detection of biological objects. This modular approach is based on open-source code and allows researchers to customise and further develop the presented functionalities to various types of data and questions related to analysis of marine imagery. We tested our approach for monitoring cold water corals in a Marine Protected Area in Sweden using videos from remotely-operated vehicles (ROVs). Our study resulted in a machine learning model with an adequate performance, which was entirely trained with classifications provided by citizen scientists. We illustrate the application of machine learning models for automated inventories and monitoring of cold water corals. Our approach shows how citizen science can be used to effectively extract occurrence and abundance data for key ecological species and habitats from underwater footage. We conclude that the combination of open-source tools, citizen science systems, machine learning and high performance computational resources are key to successfully analyse large amounts of underwater imagery in the future.
|
|
8. |
- Bergström, Per, 1980, et al.
(author)
-
Biodeposits from Mytilus edulis: a potentially high-quality food source for the polychaete, Hediste diversicolor
- 2019
-
In: Aquaculture International. - : Springer Science and Business Media LLC. - 0967-6120 .- 1573-143X. ; 27, s. 89-104
-
Journal article (peer-reviewed)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.
|
|
9. |
- Bergström, Per, 1980
(author)
-
Blue Oceans with Blue Mussels - Management and planning of mussel farming in coastal ecosystems
- 2014
-
Doctoral thesis (other academic/artistic)abstract
- Eutrophication is one of the largest and most serious global threats to the marine environment. The effect of eutrophication has become increasingly clear during recent time, and major economic and political efforts are being made to tackle its causes and consequences in Sweden and its surrounding seas. Mainly, it is the dramatic increase in the supply of nitrogen and phosphorus that has several undesirable effects on marine ecosystems. More and more emphasis is placed on how to utilize the natural processes in restoration measures of eutrophic coastal areas. One such proposition is to use mussel-farms with substantial capacity for filter-feeding to “clean” coastal waters by assimilation of particulate material and removal of potentially large amounts of nutrients from coastal areas at harvest. In this thesis, several aspects of mussel farming have been studied in a series of experiments as a step in the process to develop and evaluate the concept of mussel farming as restoration measurement in eutrophic coastal areas. The experiments were designed and attempts made to evaluate three major issues 1) effects of mussel farming on water quality, 2) spatial patterns of growth and 3) mitigation of negative effects in sediments beneath mussel farms. The first issue was attempted to evaluate using a before-after control-impact design with two mussel farms and two reference locations. Transplanted mussels were used to investigate spatial and temporal variability and thus the predictability of mussel growth. Predictive models were then developed and evaluated with the best model implemented into GIS, producing a map of predicted growth. In a series of field and laboratory experiments the survival and growth of a bioturbating polychaete on mussel faeces and the impacts on nutrient and oxygen fluxes across sediment-water interface of its activities were evaluated. Due to loss of mussels, presumably because of predation, the planned evaluation of local effects of mussel farming and its potential as a mitigation tool was not possible. This shows that the use of mussel farming in mitigation efforts is quite unpredictable and development of techniques used are needed. However, the extensive data collected can be used to evaluate spatial and temporal variability of the sampled parameters and provide important information for future attempts to evaluate effects of action programs. The studies show that growth is highly variable both between sites and times, both between and within years. Despite the variability there is some predictability in terms of growth in soft tissue, while for growth in shell length it is more difficult. Prediction of growth indicates that about 15 % of the investigated area belongs to the highest growth class. The highest growth rates were generally observed in the innermost areas, in fjords and other protected areas. These are also the areas that are in most need of restoration activities. This fact, from the perspective of utilizing mussel farming in mitigation efforts, is positive. The studies also point on the importance of understanding the complex systems in coastal areas. One environmental variable does not always influence the growth in the same manner. The influence may vary between both levels of growth and levels of the variable itself but also depends on other environmental factors within the system. Further improvement of growth prediction requires refinements of predictors with regard to both the nature and quality. As perhaps the greatest negative impact of mussel farming, it is important to minimize the effect of biodeposition on the sediment. The results indicate that the use of natural processes such as bioturbation may be a possibility. The polychaete Hediste diversicolor showed improved growth while a positive effect on the decomposition of organic matter was obtained with an improved sediment environment as a result. The effect was mainly indirect presumably through increased microbial activity due to the mechanical impact on the sediment by the polychaetes. In summary, this thesis provides important insights into several aspects of the potential and sustainability of mussel farming as a mitigation tool and the results provide a base for scientifically based planning of aquaculture. Under the right conditions, mussel farming has the potential to be a useful and sustainable mitigation method but due to the complexity of the system it can be quite unpredictable and further studies are needed. The use of bioturbation by polychaetes, and possibly other organisms, has the potential to mitigate sediments negatively impacted by mussel farms and thus has the potential to be an important component in future mitigation measure using mussel farming. However, technical developments are needed before the approach can be used in practice.
|
|
10. |
- Bergström, Per, 1980, et al.
(author)
-
Deposition of shells modify nutrient fluxes in marine sediments: effects of nutrient enrichment and mitigation by bioturbation below mussel farms
- 2020
-
In: Aquaculture Environment Interactions. - : Inter-Research Science Center. - 1869-215X .- 1869-7534. ; 12, s. 315-325
-
Journal article (peer-reviewed)abstract
- Farming of extractive species such as filter feeding bivalves has been proposed as a potential method to mitigate impacts of eutrophication in marine environments. For such efforts to be sustainable, potential negative effects from mussel farms, such as accumulation of biodeposits in sediment below them, need to be considered and addressed. Benthic burrowing macrofauna strongly influence biogeochemical processes in soft bottom marine habitats by sediment reworking and irrigation and, thus, have the potential to mitigate some of the negative impacts. However, not all biodeposits are organic matter; shells that accumulate on and in the sediment below mussel farms also have the potential to influence processes in the sediment, the activity of bioturbators and the fluxes across the sediment-water interface. In this study, we evaluated the mitigation potential of the bioturbating polychaete Hediste diversicolor in sediments enriched with mussel waste material and the relative impact of mussel shells within the sediment matrix. The polychaetes generally increased fluxes and sediment oxygen uptake. With an observed tendency of increased fluxes of nutrients in sediments containing shells compared to sediments without, the results indicate that the accumulation of shell has a potential to further increase the mitigative effect of the polychaetes by influencing the solute fluxes across the sediment-water interface.
|
|
11. |
- Bergström, Per, 1980, et al.
(author)
-
Differences in growth patterns among three bivalve species and in relation to exposure and implications for aquaculture and ecological functions
- 2024
-
In: Estuarine, Coastal and Shelf Science. - 0272-7714. ; 303
-
Journal article (peer-reviewed)abstract
- In this paper, similarities and differences in growth patterns, measured as changes in soft tissue weight and shell length, among three bivalve species in Sweden (blue mussels, Pacific oysters and European flat oysters) were studied with the aim to achieve information on spatial and temporal variability among these commercially important species. The study showed that there are significant differences in spatial growth pattern between blue mussels and both of the oyster species, where oysters grew faster in more protected locations compared to mussels, which had a generally faster growth in the exposed localities. The weight: length ratio also differed among species, where mussels had a lower ratio compared to oysters. Potential causes of the observed patterns and consequences for bivalve farming as well as implications for ecological functions are discussed. The results are valuable in site-selection processes at both local (individual farmers) and regional/national scales (planning processes etc), and indicates that spatial planning of bivalve aquaculture need inclusion of species specific growth parameters.
|
|
12. |
- Bergström, Per, 1980, et al.
(author)
-
Environmental influence on mussel (Mytilus edulis) growth - A quantile regression approach
- 2016
-
In: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714 .- 1096-0015. ; 171, s. 123-132
-
Journal article (peer-reviewed)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.
|
|
13. |
- Bergström, Per, 1980, et al.
(author)
-
Identifying high‐density areas of oysters using species distribution modeling: Lessons for conservation of the native Ostrea edulis and management of the invasive Magallana ( Crassostrea ) gigas in Sweden
- 2021
-
In: Ecology and Evolution. - : Wiley. - 2045-7758. ; 11:10, s. 5522-5532
-
Journal article (peer-reviewed)abstract
- AimUnderstanding spatial patterns of the distribution of adult native oyster, Ostrea edulis, and the invasive Magallana (Crassostrea) gigas is important for management of these populations. The aim of this study was to use ensemble SDM’s to (a) identify and predict conservation hotspots, (b) assess the current level of protection for O. edulis, and (c) quantify the amount of overlap between the two species where interactions with M. gigas are most likely.LocationSkagerrak, Sweden.MethodsWe used data collected by video at depths from 0.5 to 10 m in 436 sites. Models of occurrence and densities >1 m−2 were fitted and assessed using ensemble methods (“biomod2” package). Models of high-density hotspots were used to predict, map, and quantify areal extent of the species in order to assess the degree of overlap with protected areas and the potential for interactions between the two species.ResultsBoth species were widely distributed in the region. Observations of high-density habitats, mainly occurring at depths of ≈3 and 0.5 m for O. edulis and M. gigas, respectively, were found in 4% and 2% of the sites. Models provided useful predictions for both species (AUC = 0.85–0.99; sensitivity = 0.74–1.0; specificity = 0.72–0.97). High-density areas occupy roughly 15 km2 each with substantial overlap between species. 50% of these are protected only by fisheries regulations, 44% are found in Natura 2000 reserves and 6% of the predicted O. edulis enjoys protection in a national park.Main conclusionsData collection by video in combination with SDM’s provides a realistic approach for large-scale quantification of spatial patterns of marine population and habitats. O. edulis and M. gigas are common in the area, but a large proportion of the most valuable O. edulis habitats are not found in protected areas. The overlap between species suggests that efforts to manage the invasive M. gigas need to be integrated with management actions to conserve the native O. edulis.
|
|
14. |
- Bergström, Per, 1980, et al.
(author)
-
Inventering, metodutveckling och modellering i marin miljö i Marstrandsskärgården
- 2009
-
Reports (other academic/artistic)abstract
- Länsstyrelsen i Västra Götalands län uppdrog år 2007 åt Institutionen för Marin ekologi att med stöd av Marbipp-verktyget dels inventera grundområdena i Marstrandsskärgården i Kungälvs kommun dels utveckla/utvärdera olika inventeringsmetoder i grunda områden. År 2008 erhölls ett tilläggsuppdrag avseende arbete med habitatmodellering med data från 2007 och från nya inventeringar genomförda år 2008 av länsstyrelsen. Inventeringen har dels utförts med småbåt och vattenkikare på sedvanligt vis, dessutom har punkter slumpats ut i området till grund för en efterföljande modellering. En ny metod med transekter och avläsning med hjälp av ekolod har också prövats. Med stöd från resultat från inventeringarna och information om bland annat vågexponering är det möjligt att klassificera olika bottenhabitat enligt det europeiska systemet för habitatklassificering EUNIS (European Nature Information System). Denna klassificering har efter modellering av substrat och vegetation i icke inventerade områden genomförts för hela undersökningsområdet. Modelleringen utfördes på två separata dataset, ett innehållande inventeringsinformation från punktlokaler (dyk, bottenhugg, droppvideo och vattenkikare) samt ett med information från inventeringar över större ytor (vattenkikare och ekolodsmätningar). Modelleringen visar på att Marstrandsområdet domineras av vegetationsfria lerbottnar (A5.3) följt av moderat exponerade infralittorala hårdbottnar (A3.2) och makrofyt dominerade sublittorala sediment. I modellen som baseras på punktlokaler dominerar mjukbottnarna helt, medan i den andra modellen är det jämnare fördelat mellan mjukbottnarna och de infralittorala hårdbottnarna.
|
|
15. |
- Bergström, Per, 1980, et al.
(author)
-
Klassificering av habitat i Vinga-Fotöskärgården - Utvärdering och modellering
- 2007
-
Reports (other academic/artistic)abstract
- Det tänkta naturreservatet i Vinga-Fotöskärgården inventerades med avseende på bottentyp och -vegetation under 2006. Med hjälp det insamlade materialet och information om vågexponering kan man klassificera olika bottenhabitat enligt det europeiska systemet för habitatklassificering (European Nature Information System; EUNIS). Denna klassificering kan efter modellering av habitat i icke inventerade områden ske för hela det tilltänkta reservatet. Syftet med denna utredning var inledningsvis att: 1. Kartlägga och kvantifiera habitat enligt EUNIS inom inventerat område 2. Med hjälp av modeller uppskatta förekomsten av habitat för hela det tilltänkta reservatet. 3. Föreslå provtagningspunkter inför 2007 års inventering Under detta arbete blev det också klart att det fanns ett behov av standardisering av protokoll för informationsinsamling i fält och för inmatning av data i databas. Därför utökades uppdraget att innefatta även: 4. Förslag till fältprotokoll och databasstruktur. Eftersom insamlingen under sommaren 2007 också innebar möjligheter att utvärdera och komplettera utvecklade modeller, utökades även uppdraget till att omfatta följande syften: 5. Testa träffsäkerheten hos modeller utvecklade med data från 2006. 6. Utveckla modeller baserade på data från 2006 och 2007. Inventeringen 2006 täckte en geografiskt och miljömässigt orepresentativ del av reservatet. Detta ledde till att endast cirka 40 % av området kunde modelleras och endast ett fåtal av de tänkbara habitaten var observerade. Icke desto mindre antydde senare test med data insamlade under 2007 att träffsäkerheten var god för vissa habitat. Resultaten ledde vidare till att rekommendationer om vidare provtagning fokuserade på provtagning i punkter utspridda i hela området snarare än detaljerade kartläggningar i begränsade delar. Med data från 2006 och 2007 kunde hela reservatsområdet modelleras på ett mer tillförlitligt sätt. Dessa resultat antyder att sublittorala moderat exponerade hårdbottnar, sublittorala lerbottnar och blandade substrat är de vanligaste habitaten (A3.2, A.5.3 och X32). Utan att ha möjligheten att testa modellen med oberoende data kunde jämförelse endast ske med existerande data och modellen uppvisar då en 65 % -ig överrensstämmelse med verkligheten och föredelningen mellan olika habitat var mer eller mindre identisk mellan modellen och inventeringarna. Förvånande var att klassificeringen i den maringeologiska kartan korrekt förutsade endast 55 % av bottnarna. I övrigt ger den erhållna kartan en bild som förefaller relativt trovärdig när det gäller de stora dragen. Men eftersom den inte testats med oberoende data bör den betraktas med viss försiktighet.
|
|
16. |
- Bergström, Per, 1980, et al.
(author)
-
Modeling and predicting the growth of the mussel, Mytilus edulis: implications for planning of aquaculture and eutrophication mitigation
- 2015
-
In: Ecology and Evolution. - : Wiley. - 2045-7758. ; 5:24, s. 5920-5933
-
Journal article (peer-reviewed)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.
|
|
17. |
|
|
18. |
|
|
19. |
|
|
20. |
- Bergström, Per, 1980, et al.
(author)
-
Temporal consistency of spatial pattern in growth of the mussel, Mytilus edulis: Implications for predictive modelling
- 2013
-
In: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714 .- 1096-0015. ; 131, s. 93-102
-
Journal article (peer-reviewed)abstract
- Human pressures on coastal seas are increasing and methods for sustainable management, including spatial planning and mitigative actions, are therefore needed. In coastal areas worldwide, the development of mussel farming as an economically and ecologically sustainable industry requires geographic information on the growth and potential production capacity. In practice this means that coherent maps of temporally stable spatial patterns of growth need to be available in the planning process and that maps need to be based on mechanistic or empirical models. Therefore, as a first step towards development of models of growth, we assessed empirically the fundamental requirement that there are temporally consistent spatial patterns of growth in the blue mussel, Mytilus edulis. Using a pilot study we designed and dimensioned a transplant experiment, where the spatial consistency in the growth of mussels was evaluated at two resolutions. We found strong temporal and scale-dependent spatial variability in growth but patterns suggested that spatial patterns were uncoupled between growth of shell and that of soft tissue. Spatial patterns of shell growth were complex and largely inconsistent among years. Importantly, however, the growth of soft tissue was qualitatively consistent among years at the scale of km. The results suggest that processes affecting the whole coastal area cause substantial differences in growth of soft tissue among years but that factors varying at the scale of km create strong and persistent spatial patterns of growth, with a potential doubling of productivity by identifying the most suitable locations. We conclude that the observed spatial consistency provides a basis for further development of predictive modelling and mapping of soft tissue growth in these coastal areas. Potential causes of observed patterns, consequences for mussel-farming as a tool for mitigating eutrophication, aspects of precision of modelling and sampling of mussel growth as well as ecological functions in general are discussed. © 2013 Elsevier Ltd.
|
|
21. |
- Bergström, Per, 1980, et al.
(author)
-
Testing the potential for improving quality of sediments impacted by mussel farms using bioturbating polychaete worms
- 2017
-
In: Aquaculture Research. - : Hindawi Limited. - 1365-2109 .- 1355-557X. ; 48:1, s. 161-176
-
Journal article (peer-reviewed)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.
|
|
22. |
- Bergström, Per, 1980, et al.
(author)
-
Vägledning för marint vattenbruk i Västra Götaland
- 2020
-
Reports (other academic/artistic)abstract
- Vattenbruk har en potential att bli en viktig tillväxtnäring i framtiden. Haven är en viktig resurs och det är viktigt att våra hav nyttjas,men inte överutnyttjas. För att nå framgång krävs att utvecklingen sker på ett hållbart sätt utan negativ påverkan på vattenmiljön.Ett viktigt led i utvecklandet av ett hållbart och livskraftigt vattenbruk är att områden möjliga för vattenbruket identifieras och integreras i planeringen av havsresursernas utnyttjande samt att processen från vattenbruksidé till verklig-het underlättas. Den här vägledningenför vattenbruk i de marina delarna av Västra Götalands län är ett led i det främjande arbetetoch ettverktyg i den fortsatta utvecklingen av vattenbruket i länets marina delar. Vägledningen un-derlättar identifiering av möjliga områden och samlar nödvändig information som tex vilka tillstånd som behövs,i vilken ordningde söksoch var man ansö-ker om dessa. Vägledningenvisar områden som generellt sett är möjliga för vattenbruk. Enprövning av lämpligheten av odling på en specifik plats måste dock alltid göras i varje enskilt fall.Att en yta i denna vägledning harutpekatssom ettmöjligt område innebär således inte per automatik att ett tillstånd gesochej heller att en tillståndsansökan alltid avslås i ejutpekade områden.Vägledningen baserastill stor del på de områden för norra Bohuslän som iden-tifierats som möjliga för vattenbruk inom projektet ”Vattenbruk på Västkusten” och områden som i ett senare skede identifierats på motsvarande vis för 8-fjordarområdet. Rapporten har tagits fram och bearbetats av Per Bergströmvid Göteborgs universitetoch Fredrik Larson vid Vattenavdelningenmed värde-fullt bidrag från Anita Tullrot vid Kosterhavets nationalpark, samt uppdatering av kartmaterial av Emelie Müller vid Vattenmyndigheten.
|
|
23. |
- Buer, A. L., et al.
(author)
-
Nitrogen and Phosphorous Content in Blue Mussels (Mytilus spp.) Across the Baltic Sea
- 2020
-
In: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 7
-
Journal article (peer-reviewed)abstract
- To support the ongoing discussion about mussel farming and the potential to extract nutrients from the sea, this study investigated the phosphorus (P) and nitrogen (N) content of blue mussels (Mytilus spp.) under different abiotic and biotic parameters. The focus of this survey was on the highly eutrophied Baltic Sea, where salinity ranges from 4 to 27 psu, and is a major contributing factor to differential mussel growth. We observed that nutrient content was not linearly correlated to salinity, but if categorized, decreased at higher salinities. Chlorophyll-a and temperature did not significantly correlate with nutrient content, but season of harvest and mussel size did. Furthermore, habitat was a strong driver of nutrient content, indicating higher nutrient density if mussels are grown in mussel farms (i.e., in the water column) instead of on mussel culture beds or harvested from wild beds (on the sea bed). Values of N and P averaged 5.85% N and 0.83% P of tissue dry weight in mussels at the sea bed and 9.43% N and 0.96% P of tissue dry weight in mussels from longline cultivation. These results will be useful in refining estimations about mussel farming as a nutrient mitigation measure and the extraction potential, as well as related costs.
|
|
24. |
|
|
25. |
|
|