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- Bergström, Per, 1980, et al.
(författare)
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Differences in growth patterns among three bivalve species and in relation to exposure and implications for aquaculture and ecological functions
- 2024
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Ingår i: Estuarine, Coastal and Shelf Science. - 0272-7714. ; 303
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Tidskriftsartikel (refereegranskat)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.
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| 2. |
- 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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| 4. |
- Bergström, Per, 1980, et al.
(författare)
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Temporal consistency of spatial pattern in growth of the mussel, Mytilus edulis: Implications for predictive modelling
- 2013
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Ingår i: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714 .- 1096-0015. ; 131, s. 93-102
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Tidskriftsartikel (refereegranskat)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.
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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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| 8. |
- Mafambissa, Mizeque, et al.
(författare)
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Experimental spat collection of the pearl and rocky shore oysters on ceramic tile substrates
- 2024
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Ingår i: Aquaculture Reports. - 2352-5134. ; 36
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Tidskriftsartikel (refereegranskat)abstract
- Temporal and spatial variation in oyster larvae settlement is a crucial factor determining the abundance and success of adult populations in their natural environment. The overall understanding of oyster recruitment provides information on site selection and strategies employed for obtaining spats for oyster culture. In this study, spat of Pinctada capensis and Saccostrea cucullata were collected from four selected sites in a sub-tropical setting at Inhaca Island, Southern Mozambique during an experimental period of 8 months to assess the effect of different factors (season, duration and surface) on spat settlement and abundance. Ceramic tiles were deployed as artificial substrates from the surface to 5 m depth. They were replaced monthly. Overall, settlement on ceramic tiles was higher for S. cucullata than for pearl oyster P. capensis. There was a tendency for higher numbers of spat settling during the summer than winter for both species. For both species larger numbers of recruits were found on tiles deployed for four months than for two months and on the roughly textured surfaces compared to smooth. The results have also indicated that the ceramic tiles could be used as substrate for rocky shore oyster S. cucullata settlement in the late summer.
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| 9. |
- Mattsson-Thorngren, Linnea, et al.
(författare)
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Developing methods for assessing abundance and distribution of European oysters (Ostrea edulis) using towed video
- 2017
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 12:11
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Tidskriftsartikel (refereegranskat)abstract
- Due to large-scale habitat losses and increasing pressures, benthic habitats in general, and perhaps oyster beds in particular, are commonly in decline and severely threatened on regional and global scales. Appropriate and cost-efficient methods for mapping and monitoring of the distribution, abundance and quality of remaining oyster populations are fundamental for sustainable management and conservation of these habitats and their associated values. Towed video has emerged as a promising method for surveying benthic communities in a both non-destructive and cost-efficient way. Here we examine its use as a tool for quantification and monitoring of oyster populations by (i) analysing how well abundances can be estimated and how living Ostrea edulis individuals can be distinguished from dead ones, (ii) estimating the variability within and among observers as well as the spatial variability at a number of scales, and finally (iii) evaluating the precision of estimated abundances under different scenarios for monitoring. Overall, the results show that the can be used to quantify abundance and occurrence of Ostrea edulis in heterogeneous environments. There was a strong correlation between abundances determined in the field and abundances estimated by video-analyses (r2 = 0.93), even though video analyses underestimated the total abundance of living oysters by 20%. Additionally, the method was largely repeatable within and among observers and revealed no evident bias in identification of living and dead oysters. We also concluded that the spatial variability was an order of magnitude larger than that due to observer errors. Subsequent modelling of precision showed that the total area sampled was the main determinant of precision and provided general method for determining precision. This study provides a thorough validation of the application of towed video on quantitative estimations of live oysters. The results suggest that the method can indeed be very useful for this purpose and we therefor recommend it for future monitoring of oysters and other threatened habitats and species. © 2017 Thorngren et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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