SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Visch Wouter) "

Sökning: WFRF:(Visch Wouter)

  • Resultat 1-9 av 9
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Glykou, Aikaterini, et al. (författare)
  • Strontium isotope analysis in prehistoric cod otoliths by laser ablation multi-collector inductively coupled plasma mass spectrometry
  • 2021
  • Ingår i: Journal of Archaeological Science-Reports. - : Elsevier BV. - 2352-409X .- 2352-4103. ; 37
  • Tidskriftsartikel (refereegranskat)abstract
    • Exploitation of aquatic resources, especially fishing, was a fundamental part of human subsistence during the Late Mesolithic Ertebolle culture (5400-4000/3900 cal BC) in Southern Scandinavia. In this pilot study we examine three cod otoliths from two Late Mesolithic locations in eastern Denmark to see whether local environmental conditions are reflected in the strontium ratios of the fish, to source the fish to either the Atlantic or the Baltic Sea and finally, to explore how fishing was conducted in relation to the settlements. We used laser ablation multi-collector inductively coupled plasma mass spectrometry for sequential sampling of the otoliths for strontium isotope analysis. All three otoliths yielded Sr-87/Sr-86 values that fall within the range of Baltic Sea water, thus indicating that cod caught by Mesolithic fishers in the Danish straits belonged to the Baltic Sea stock. Our results suggest that cod were not caught in waters immediately adjacent to the archaeological sites but rather came from the Kattegat. We could not detect any substantial change in habitat between juvenile and mature stages of the fishs lives. Our study shows the potential of isotopic analysis to address issues regarding the individual ecological history of fish and human fishing strategies.
  •  
2.
  • Hasselström, Linus, et al. (författare)
  • The impact of seaweed cultivation on ecosystem services - a case study from the west coast of Sweden
  • 2018
  • Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 133, s. 53-64
  • Tidskriftsartikel (refereegranskat)abstract
    • © 2018 The Authors Seaweed cultivation attracts growing interest and sustainability assessments from various perspectives are needed. The paper presents a holistic qualitative assessment of ecosystem services affected by seaweed cultivation on the Swedish west coast. Results suggest that supporting, regulating and provisioning services are mainly positively or non-affected while some of the cultural services are likely negatively affected. The analysis opens for a discussion on the framing of seaweed cultivation – is it a w ay of supplying ecosystem services and/or a way of generating valuable biomass? Exploring these framings further in local contexts may be valuable for identifying trade-offs and designing appropriate policies and development strategies. Many of the found impacts are likely generalizable in their character across sites and scales of cultivation, but for some services, including most of the supporting services, the character of impacts is likely to be site-specific and not generalizable.
  •  
3.
  • Kotta, Jonne, et al. (författare)
  • Assessing the potential for sea-based macroalgae cultivation and its application for nutrient removal in the Baltic Sea
  • 2022
  • Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 839
  • Tidskriftsartikel (refereegranskat)abstract
    • Marine eutrophication is a pervasive and growing threat to global sustainability. Macroalgal cultivation is a promising circular economy solution to achieve nutrient reduction and food security. However, the location of production hotspots is not well known. In this paper the production potential of macroalgae of high commercial value was predicted across the Baltic Sea region. In addition, the nutrient limitation within and adjacent to macroalgal farms was investigated to suggest optimal site-specific configuration of farms. The production potential of Saccharina latissima was largely driven by salinity and the highest production yields are expected in the westernmost Baltic Sea areas where salinity is >23. The direct and interactive effects of light availability, temperature, salinity and nutrient concentrations regulated the predicted changes in the production of Ulva intestinalis and Fucus vesiculosus. The western and southern Baltic Sea exhibited the highest farming potential for these species, with promising areas also in the eastern Baltic Sea. Macroalgal farming did not induce significant nutrient limitation. The expected spatial propagation of nutrient limitation caused by macroalgal farming was less than 100–250 m. Higher propagation distances were found in areas of low nutrient and low water exchange (e.g. offshore areas in the Baltic Proper) and smaller distances in areas of high nutrient and high water exchange (e.g. western Baltic Sea and Gulf of Riga). The generated maps provide the most sought-after input to support blue growth initiatives that foster the sustainable development of macroalgal cultivation and reduction of in situ nutrient loads in the Baltic Sea.
  •  
4.
  • Visch, Wouter, et al. (författare)
  • Adherence of kelp (Saccharina latissima) gametophytes on ropes with different binder treatments and flow regimes
  • 2022
  • Ingår i: Journal of Applied Phycology. - : Springer Science and Business Media LLC. - 0921-8971 .- 1573-5176.
  • Tidskriftsartikel (refereegranskat)abstract
    • The cultivation of kelp typically involves two stages, where an indoor hatchery phase preceedes the grow-out phase at-sea. The in situ adhesion of microscopic propagules onto specifically designed substrates using binders has been proposed as an alternative to conventional hatchery methods where juvenile seaweeds are cultured on seeded twine, aimed at saving resources while increasing productivity as it obviates the hatchery phase. Here we tested how well kelp (Saccharina latissima) gametophytes adhere to cultivation ropes using two binder types (agar and κ-carrageenan) and application treatment (separate or mixed application) under two ecologically relevant flow regimes (5 and 15cms−1), and a control condition (0cms−1) in a laboratory flume. Our findings indicate that the effectiveness of a binder to retain S. latissima gametophytes onto cultivation rope, measured by the sporophyte density, was comparable for all binder types in the high flow velocity (15cms−1) treatments, including the non-binder control treatment. Sporophyte densities were highest in the low flow velocities (0 and 5cms−1) in the absence of a binder compared to all other treatment combinations. In conclusion, our results highlight that the effectiveness of binder assisted seeding of kelp propagules did not differ between the binder and non-binder treatments and was unaffected by flow velocities for the binder treatments. These findings are important in the development of novel methods and further optimisation of existing binder-based methods aimed at retaining seaweed propagules onto cultivation rope.
  •  
5.
  • Visch, Wouter, et al. (författare)
  • Environmental impact of kelp (Saccharina latissima) aquaculture
  • 2020
  • Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 155
  • Tidskriftsartikel (refereegranskat)abstract
    • © 2020 The Authors The aim of the study was to assess the effect of seaweed cultivation on the coastal environment. We analysed a multitude of environmental parameters using an asymmetrical before after control impact (BACI) design, comparing the seaweed farm (impact) with multiple unaffected locations (controls). The seaweed farm had a significant positive effect on benthic infauna (p < 0.05) and was found to attract 17 mobile faunal and 7 other seaweed species, indicating that the farmed crop may provide habitat to mobile faunal species. A light attenuation of approximately 40% at 5 m depth was noted at the peak of the seaweed biomass just before harvest. No changes were observed in benthic oxygen flux, dissolved nutrient concentrations, and benthic mobile fauna between farm and control sites. These results show that seaweed aquaculture has limited environmental effects, especially compared to other forms of aquaculture such as fish and bivalve farming.
  •  
6.
  • Visch, Wouter, et al. (författare)
  • Growth and biofouling in kelp aquaculture (Saccharina latissima): the effect of location and wave exposure
  • 2020
  • Ingår i: Journal of Applied Phycology. - : Springer Science and Business Media LLC. - 0921-8971 .- 1573-5176.
  • Tidskriftsartikel (refereegranskat)abstract
    • Seaweed aquaculture is receiving increasing attention for food and non-food applications in Europe, where it is still an emerging industry. The cultivation of seaweeds in the sea is attractive as it does not compete with agricultural crops for land and freshwater, whilst generating high yearly biomass yield. The selection of suitable cultivation sites in coastal waters is essential for the sustainable establishment and further development of seaweed aquaculture in Europe. Here, we investigate the effects of wave exposure and geographic location on growth and biofouling of kelp (Saccharina latissima), using a transplantation experiment along the Swedish west coast. Biofouling of kelp decreased with increased wave exposure, from 10 and 6% coverage at sheltered and moderately exposed locations, respectively, to 3% at exposed locations. Growth, measured as blade surface area, generally increased with decreased wave exposure, with approximately 40% less growth at exposed locations compared to sheltered or moderately exposed location. We identified that there is large spatial variation in growth and fouling of the seaweed biomass at the selected farm sites, with significant differences from the km-scale to the m-scale. In addition, exposure level affected the tissue composition, with a high carbon, but low nitrogen and water content at exposed locations compared to moderate and sheltered sites. Isotope signatures (i.e. delta C-13 and delta N-15) also differed between exposure levels. Together, these results indicate that wave exposure is an important factor to consider in site selection for both yield as well as quality of the seaweed biomass for future kelp farms.
  •  
7.
  • Visch, Wouter, et al. (författare)
  • Spatial differences in growth rate and nutrient mitigation of two co-cultivated, extractive species: The blue mussel (Mytilus edulis) and the kelp (Saccharina latissima)
  • 2020
  • Ingår i: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714. ; 246
  • Tidskriftsartikel (refereegranskat)abstract
    • © 2020 Cultivation of extractive species, such as bivalves and seaweeds, provides opportunities for food production while removing excess nutrients in eutrophic coastal waters. However, to optimize these ecosystem services, selecting aquaculture sites that affect growth and nutrient uptake is important. In a transplant experiment we assessed spatial growth patterns of the blue mussel Mytilus edulis and the kelp Saccharina latissima, which were used to estimate nutrient removal. Optimal locations for growth and nutrient extraction differed, mussels grew better in relatively sheltered inner coastal areas, whereas seaweed growth increased in outer more exposed coastal areas. Estimates of mitigatory capacity indicated that under the best available conditions, mussels remove approximately 700 kg N and 6600 kg C ha−1yr−1, whereas seaweed removes approximately 100 kg N and 1000 kg C ha−1yr−1. We identified the importance of site selection for the overall capacity of two extractive species (bivalves and seaweeds) in order to synergistically maximise their growth and nutrient mitigation.
  •  
8.
  • Visch, Wouter (författare)
  • Sustainable Kelp Aquaculture in Sweden
  • 2019
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Seaweed aquaculture is gaining more interest worldwide, including Europe. However, despite its long coast seaweed farming is still very minor in Sweden. The overarching aim of this thesis is to develop sustainable cultivation methods for Sugar kelp (Saccharina latissima) in Sweden, with more specific focus on (1) the effect of seaweed farming on ecosystem services and its environmental impact, (2) spatial location of farm sites, and (3) the development of new techniques and knowledge for selective breeding programs. An ecosystem services assessment combined with the analysis of various environmental parameters in the field were used to study environmental impact associated with a two-hectare kelp farm. The ecosystem services assessment indicated positive or no effect on provisioning (e.g. food, biomaterials), supporting (e.g. habitat, biodiversity), and regulating (e.g. mitigating eutrophication) ecosystem services. However, some cultural ecosystem services such as recreation and aesthetic values, were likely negatively affected. The results from the environmental impact study showed that the seaweed farm has very limited negative environmental effects, but can rather have a positive effect on some environmental parameters. The selection of suitable cultivation sites in coastal waters is essential for the sustainable establishment and further development of seaweed aquaculture in previously unexplored regions. In two field studies I investigated spatial growth patterns of S. latissima for optimising its nutrient mitigation capacity, crop yield, and crop quality (i.e. biofouling). The results indicate that there is relatively large spatial variation in growth and nutrient mitigation capacity of farmed seaweed biomass. Biofouling and growth decreased with increasing exposure levels, indicating that wave exposure is an important factor for site selection. Furthermore, the capacity to conserve genetic diversity through cryo-preservation of gametophytic cells (i.e. haploid life stage) was found to be an attractive preservation method. The results show that after thawing the preserved gametophytes may serve as seed stock for onward cultivation or in selective breeding programs. A successful domestication commonly starts with a base knowledge of the genetic population structure and diversity of the species of interest. Therefore, this was assessed for S. latissima along the Swedish west coast, using genomic sequencing (ddRAD). The results suggest a well-connected meta-population along the Swedish west coast, but with clear signals of adaptive divergence between sub-populations, most likely driven by environmental selection. This indicates strong natural selection in the heterogeneous marine coastal environment, leading to local adaptations despite high gene flow and connectivity.
  •  
9.
  • Visch, Wouter, et al. (författare)
  • Underpinning the Development of Seaweed Biotechnology: Cryopreservation of Brown Algae (Saccharina latissima) Gametophytes
  • 2019
  • Ingår i: Biopreservation and Biobanking. - : Mary Ann Liebert Inc. - 1947-5535 .- 1947-5543. ; 17:5, s. 378-386
  • Tidskriftsartikel (refereegranskat)abstract
    • Sugar kelp (Saccharina latissima) is an economically important species, and natural populations provide diverse and productive habitats as well as important ecosystem services. For seaweed aquaculture to be successful in newly emerging industry in Europe and other Western countries, it will have to develop sustainable production management strategies. A key feature in this process is the capacity to conserve genetic diversity for breeding programs aimed at developing seed stock for onward cultivation, as well as in the management of wild populations, as potentially interesting genetic resources are predicted to disappear due to climate change. In this study, the cryopreservation of male and female gametophytes (haploid life stage) of S. latissima by different combinations of two-step cooling methods and cryoprotectants was explored. We report here that cryopreservation constitutes an attractive option for the long-term preservation of S. latissima gametophytes, with viable cells in all treatment combinations. The highest viabilities for both male and female gametophytes were found using controlled-rate cooling methods combined with dimethyl sulfoxide 10% (v/v). Morphological normal sporophytes were observed to develop from cryopreserved vegetative gametophytic cells, independent of treatment. This indicates that cryopreservation is a useful preservation method for male and female S. latissima gametophytes.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-9 av 9

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy