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  • 1.
    Abbott, D. Wade
    et al.
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Aasen, Inga Marie
    SINTEF Ind, Dept Biotechnol & Nanomed, N-7465 Trondheim, Norway..
    Beauchemin, Karen A.
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gruninger, Robert
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Hayes, Maria
    Teagasc Food Res Ctr, Food BioSci Dept, Dublin D15 KN3K 15, Ireland..
    Huws, Sharon
    Queens Univ Belfast QUB, Belfast BT7 1NN, Antrim, North Ireland..
    Kenny, David A.
    Anim Biosci Res Ctr, Dunsany 5 PW93, Meath, Ireland..
    Krizsan, Sophie J.
    Swedish Univ Agr Sci, Dept Agr Res Northern Sweden, SE-90183 Umeå, Sweden..
    Kirwan, Stuart E.
    Anim Biosci Res Ctr, Dunsany 5 PW93, Meath, Ireland..
    Lind, Vibeke
    Norwegian Inst Bioecon Res NIBIO, Post Box 115, N-1431 As, Norway..
    Meyer, Ulrich
    Fed Res Inst Anim Hlth, Friedrich Loeffler Inst FLI, Bundesforsch Inst Tiergesundheit, D-38116 Braunschweig, Germany..
    Ramin, Mohammad
    Swedish Univ Agr Sci, Dept Agr Res Northern Sweden, SE-90183 Umeå, Sweden..
    Theodoridou, Katerina
    Queens Univ Belfast QUB, Belfast BT7 1NN, Antrim, North Ireland..
    von Soosten, Dirk
    Fed Res Inst Anim Hlth, Friedrich Loeffler Inst FLI, Bundesforsch Inst Tiergesundheit, D-38116 Braunschweig, Germany..
    Walsh, Pamela J.
    Queens Univ Belfast QUB, Belfast BT7 1NN, Antrim, North Ireland..
    Waters, Sinead
    Anim Biosci Res Ctr, Dunsany 5 PW93, Meath, Ireland..
    Xing, Xiaohui
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Seaweed and Seaweed Bioactives for Mitigation of Enteric Methane: Challenges and Opportunities2020In: Animals, E-ISSN 2076-2615, Vol. 10, no 12, article id 2432Article, review/survey (Refereed)
    Abstract [en]

    Simple Summary The need to become more efficient in agriculture and the food industry exists parallel to the challenge of climate change. Meat and dairy production is the target of much scrutiny due to methane (CH4) emissions and global warming. On the other hand, it should be noted that two-thirds of the world's agricultural land consists of pastures and permanent grasslands and is used for livestock grazing. This land is predominantly unsuitable for arable purposes but facilitates the production of high-quality human-edible protein in the form of ruminant animal-derived meat and milk. This makes a significant contribution to feeding the world's population. There is a need to reduce CH4 emissions, however, and several approaches are being researched currently. Seaweeds are diverse plants containing bioactives that differ from their terrestrial counterparts and they are increasingly under investigation as a feed supplement for the mitigation of enteric CH4. Seaweeds are rich in bioactives including proteins, carbohydrates and to a lesser extent lipids, saponins, alkaloids and peptides. These bioactives could also play a role as feed ingredients to reduce enteric CH4. This review collates information on seaweeds and seaweed bioactives and their potential to impact on enteric CH4 emissions. Seaweeds contain a myriad of nutrients and bioactives including proteins, carbohydrates and to a lesser extent lipids as well as small molecules including peptides, saponins, alkaloids and pigments. The bioactive bromoform found in the red seaweed Asparagopsis taxiformis has been identified as an agent that can reduce enteric CH4 production from livestock significantly. However, sustainable supply of this seaweed is a problem and there are some concerns over its sustainable production and potential negative environmental impacts on the ozone layer and the health impacts of bromoform. This review collates information on seaweeds and seaweed bioactives and the documented impact on CH4 emissions in vitro and in vivo as well as associated environmental, economic and health impacts.

  • 2.
    Björk, Mats
    et al.
    Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91, Stockholm, Sweden.
    Rosenqvist, Gunilla
    Blue Centre Gotland, Uppsala University-Campus Gotland, 621 67, Visby, Sweden.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Bonaglia, Stefano
    Department of Marine Sciences, University of Gothenburg, Box 461, 405 30, Gothenburg, Sweden, Box 461.
    Methane emissions from macrophyte beach wrack on Baltic seashores2023In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 52, no 1, p. 171-181Article in journal (Refereed)
    Abstract [en]

    Beach wrack of marine macrophytes is a natural component of many beaches. To test if such wrack emits the potent greenhouse gas methane, field measurements were made at different seasons on beach wrack depositions of different ages, exposure, and distance from the water. Methane emissions varied greatly, from 0 to 176 mg CH4-C m−2 day−1, with a clear positive correlation between emission and temperature. Dry wrack had lower emissions than wet. Using temperature data from 2016 to 2020, seasonal changes in fluxes were calculated for a natural wrack accumulation area. Such calculated average emissions were close to zero during winter, but peaked in summer, with very high emissions when daily temperatures exceeded 20 °C. We conclude that waterlogged beach wrack significantly contributes to greenhouse gas emissions and that emissions might drastically increase with increasing global temperatures. When beach wrack is collected into heaps away from the water, the emissions are however close to zero.

  • 3.
    Brandt, Nils
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Iital, A
    Loigu, E
    Changes in the Nutrient Mass Balance of Haapsalu Bay, Baltic Sea, Estonia in Relation to the Establishment of a Sewage Treatment Plant2008In: Hydrobiology, In PressArticle in journal (Other academic)
  • 4.
    Brandt, Nils
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Victorova, E. V
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Ecological Researchers Part 1.: Environmental Sensitivity Monitoring of the Coastal Zone in Primorsk Area2007Report (Other academic)
  • 5. Flaga, A.
    et al.
    Stypka, T.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Polish-Swedish Environmental Management Course: An Integrated Tool for Teaching Sustainable Development2005In: Commiting Universities to Sustainable Development, Graz, Austria: RNS TU Graz , 2005, p. 379-384Conference paper (Refereed)
  • 6.
    Franzen, Johan.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Infantes, Eduardo
    Univ Gothenburg, Dept Marine Sci, Kristineberg Stn, Kristineberg 566, SE-45178 Fiskebackskil, Sweden..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Beach-cast as biofertiliser in the Baltic Sea region-potential limitations due to cadmium-content2019In: Ocean and Coastal Management, ISSN 0964-5691, E-ISSN 1873-524X, Vol. 169, p. 20-26Article in journal (Refereed)
    Abstract [en]

    Macroalgal mass blooms and accumulating beach-cast are increasing problems in many coastal areas. However, beach-cast is also a potentially valuable marine bioresource, e.g. as a biofertiliser in coastal agriculture. One limiting factor in use of beach-cast as a fertiliser is uncertainty regarding the cadmium (Cd) concentration depending on beach-cast composition and location. In this study, chemical analyses were performed on beach cast from Burgsviken Bay off Gotland, in the Baltic Sea. The results revealed large variations in cadmium concentration depending on sampling location and beach-cast composition, with levels ranging between 0.13 and 2.2 mg Cd/kg dry matter (DM). Of 15 beach-cast samples analysed, one had a cadmium content above the Swedish statutory limit for sewage sludge biofertiliser (2 mg Cd/kg DM) and four had values above the limit suggested by the Swedish Environmental Protection Agency for 2030 (0.8 mg/kg DM). Species-specific analysis revealed that eelgrass (Zostera marina) contained significantly higher cadmium concentrations than filamentous red algae species (Ceramium and Polysiphonia spp.). Avoiding eelgrass-rich beach-cast by seasonal timing of harvesting and monitoring differences in cadmium concentrations between harvesting sites could thus facilitate use of beach-cast as biofertiliser.

  • 7.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    A Comparative Study of Three Different Methods to Measure Ecological Sensitivity, presented at the Seminar Integrated Costal Zone Management for Sustainable Development, March 1-2, 2007: Report to Tacis CBC - Decision Making Tools for Implementation of Integrated Coastal Zone Management (ICZM) in Primorsk Area2007Report (Other academic)
  • 8.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    A Summary of Sensitivity and Habitat Mapping Initiatives. Report to Tacis CBC: Decision Making Tools for Implementation of Integrated Coastal Zone Management (ICZM)2007Report (Other academic)
  • 9.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Chemical Analysis of Water and Sediments - Coastman - Estonia, Fauna and Flora2005In: Report to the Department of Environmental Engineering, Tallinn, Technical University, Estonia: European Comission in Estonia , 2005Chapter in book (Refereed)
  • 10.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Förödelsen i miljökatastrofens spår2005In: Forskning & Framsteg, ISSN 0015-7937, no 4, p. 58-62Article in journal (Other (popular science, discussion, etc.))
  • 11.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Havets Okända resurs: WWF EKO2007Report (Other academic)
  • 12.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Naturens fantastiska ljusfenomen2005In: WWF-eko : tidskrift för WWF vänner, ISSN 0284-5423, no 2Article in journal (Other (popular science, discussion, etc.))
  • 13.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Removal of Surface Blooms of the Cyanobacteria Nodularia spumigena: A Pilot Project Conducted in the Baltic Sea2009In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 38, no 2, p. 79-84Article in journal (Refereed)
    Abstract [en]

    Blooms of Cyanobacteria are a major concern during the summer period in the Baltic Sea Proper. The nitrogen-fixing Nodularia spumigena forms massive toxic blooms in the surface layers, with a concentration of biomass in the uppermost 1-m water layer. This pilot study describes the construction and test of a Nodularia collecting device during the summer of 2006. Oil booms were modified so that their dragging skirt was replaced with a water-permeable forming fabric used in the pulp and paper industry. The results showed that the modified oil booms worked and operated in an effective way when towed in the sea. Calculations showed that the collecting device used in this study has a theoretical capacity of cleaning 0.055 km(2) (5.5 ha) of sea surface hr(-1), compared with the 6600 km(2) of the Baltic Sea that were covered by Nodularia blooms during the summer of 2005. Future possibilities for Nodularia harvesting are discussed.

  • 14.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Sustainablie Development in Higher Education: a Swedish perspective, to the Northeast Campus Sustainability Consortium (NECSC) 20062006Report (Other academic)
  • 15.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    The Removal of Surface Blooms of the Cyanobacteria Nodularia spumigena2007In: :  , 2007Conference paper (Other academic)
  • 16.
    Gröndahl, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Brandt, Nils
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Karlsson, Sara
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Malmström, Maria E.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Sustainable use of Baltic Sea natural resources based on ecological engineering and biogas production2009In: ECOSYSTEMS AND SUSTAINABLE DEVELOPMENT VII / [ed] Brebbia CA; Tiezzi E, 2009, Vol. 122, p. 153-161Conference paper (Refereed)
    Abstract [en]

    Eutrophication is a major threat to the Baltic Sea, causing algae blooms and hypoxic bottoms. Ecological engineering methods aiming at help mitigating the nutrient imbalance problems have already been initiated or are being planned in the coastal zones of the Baltic Sea. This includes harvesting of reed, macro algae and blue mussels as nutrient and energy natural resources. The potential and feasibility of such methods to form the basis for sustainable use of natural resources is governed by the ecological, technical, economic and social aspects associated with the whole chain of processes from biomass to end products, e.g. biogas, fertilizers, and wastes. As a first step in a sustainability assessment, we show that biogas production from algae and reed is associated with a net energy benefit. Blue mussels do not result in a net energy benefit if used for biogas production, but represent the most efficient way of removing nutrients. Based on these preliminary results, we suggest that biogas production from reed and macro algae is worthy of further investigation, whereas for blue mussels, an alternative product must be found.

  • 17.
    Gröndahl, Fredrik
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Franzén, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    A Practical Approach to Integrating Research and Education: A Course Experiment from KTH, Sweden2016In: New Developments in Engineering Education for Sustainable Development / [ed] Walter Leal Filho, Susan Nesbit, Cham: Springer , 2016, p. 69-79Chapter in book (Refereed)
    Abstract [en]

    In this study we evaluate a project-based learning course called Applied Ecology, within the master program Sustainable Technology at the Division of Industrial Ecology, at KTH—Royal Institute of Technology in Stockholm, Sweden. The case study in the course is focused on the effects of a relatively large Bay, “Burgsviken”, situated on the island Gotland in the middle of the Baltic Sea, that has changed due to the eutrophication in the area. The eutrophication of the Bay has initiated bottom up processes of discussion and engagement among the stakeholders in the area, for the enhancement of the water quality and biological services of the bay, that would in turn improve fishing, swimming, biological diversity and tourism. There are several stakeholders involved in the project: a local non-profit organisation, farmers, entrepreneurs, authorities, permanent and seasonal inhabitants, researchers and others. The course is evaluated according to the methodology of Brundiers and Wiek (2013). Student evaluations have been conducted and analysed in relation to four phases: (1) Orienting phase, formulation of research question. (2) Framing phase, methodology and study planning. (3) Research phase, field study and other examinations. (4) Implementation phase, communication of the results with different stakeholders. The Applied Ecology course shares many of the positive features of other PPBL courses in the sustainability field—namely that it focuses on a real sustainability problem and that the student-centred learning approach and interactions between students and stakeholders make the student partnership in the project feel real, thus providing a practical insight of complex societal challenges. There are potential ways of improving all four phases of the course that were studied, but especially in the research phase and the implementation phase more efforts are needed. Feedback and reflections in the research phase could be improved by a clearer communication and to some extent changed pedagogical process through the course. All phases will be improved by increased communication before, during and after fieldwork between student, teachers and stakeholders.

  • 18.
    Gröndahl, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Muller, M.
    The Trelleborg Concept2008In: Baltic Cities Environmental bulletin, ISSN 1455-0903, Vol. 2, no 08, p. 13-Article in journal (Other academic)
  • 19.
    Gröndahl, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Peipke, E
    Wessman, M
    The Removal of Surface Blooms of Nodularia Spumigena: A Pilot Project Conducted in the Baltic Sea. Report to Richerts Fond2007Report (Other academic)
  • 20.
    Gröndahl, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Sidenmark, J.
    Thomsen, Ann
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Survey of waste water disposal practices at Antarctic research stations2009In: Polar Research, ISSN 0800-0395, E-ISSN 1751-8369, Vol. 28, no 2, p. 298-306Article in journal (Refereed)
    Abstract [en]

    To inform the future practices to be employed for handling waste water and grey water at the Swedish Antarctic station, Wasa, in Dronning Maud Land, the Swedish Polar Research Secretariat took the initiative to survey the practices of the 28 nations with stations in Antarctica. A questionnaire was sent out to all members of the Antarctic Environment Officers Network during the autumn of 2005. Questions were asked about the handling of waste water and grey water, the type of sewage treatment, and installation and operational costs. The response to the questionnaire was very good (79%), and the results showed that 37% of the permanent stations and 69% of the summer stations lack any form of treatment facility. When waste water and grey water containing microorganisms are released, these microorganisms can remain viable in low-temperature Antarctic conditions for prolonged periods. Microorganisms may also have the potential to infect and cause disease, or become part of the gut flora of local bird and mammal populations, and fish and marine invertebrates. The results from 71 stations show that much can still be done by the 28 nations operating the 82 research stations in Antarctica. The technology exists for effective waste water treatment in the challenging Antarctic conditions. The use of efficient technology at all permanent Antarctic research stations would greatly reduce the human impact on the pristine Antarctic environment. In order to protect the Antarctic environment from infectious agents introduced by humans, consideration should also be given to preventing the release of untreated waste water and grey water from the smaller summer stations.

  • 21.
    Gröndahl, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Svanström, Magdalena
    Chalmers kemi- och bioteknik.
    Hållbar utveckling - en introduktion för ingenjörer och andra problemlösare2011 (ed. 01)Book (Other academic)
  • 22.
    Guinguina, Abdulai
    et al.
    Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden; Animal Nutrition, Production Systems, Natural Resources Institute Finland (LUKE), Jokioinen, 31600, Finland.
    Hayes, Maria
    Food BioSciences Department, Teagasc Food Research Centre, Ashtown, 15 Dublin, Ireland.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Krizsan, Sophie Julie
    Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden.
    Potential of the Red Macroalga Bonnemaisonia hamifera in Reducing Methane Emissions from Ruminants2023In: Animals, E-ISSN 2076-2615, Vol. 13, no 18, article id 2925Article in journal (Refereed)
    Abstract [en]

    Researchers have been exploring seaweeds to reduce methane (CH4) emissions from livestock. This study aimed to investigate the potential of a red macroalga, B. hamifera, as an alternative to mitigate CH4 emissions. B. hamifera, harvested from the west coast of Sweden, was used in an in vitro experiment using a fully automated gas production system. The experiment was a randomized complete block design consisting of a 48 h incubation that included a control (grass silage) and B. hamifera inclusions at 2.5%, 5.0%, and 7.5% of grass silage OM mixed with buffered rumen fluid. Predicted in vivo CH4 production and total gas production were estimated by applying a set of models to the gas production data and in vitro fermentation characteristics were evaluated. The results demonstrated that the inclusion of B. hamifera reduced (p = 0.01) predicted in vivo CH4 and total gas productions, and total gas production linearly decreased (p = 0.03) with inclusion of B. hamifera. The molar proportion of propionate increased (p = 0.03) while isovalerate decreased (p = 0.04) with inclusion of B. hamifera. Chemical analyses revealed that B. hamifera had moderate concentrations of polyphenols. The iodine content was low, and there was no detectable bromoform, suggesting quality advantages over Asparagopsis taxiformis. Additionally, B. hamifera exhibited antioxidant activity similar to Resveratrol. The findings of this study indicated that B. hamifera harvested from temperate waters of Sweden possesses capacity to mitigate CH4 in vitro.

  • 23.
    Hasselström, Linus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Payments for nutrient uptake in the blue bioeconomy & ndash; When to be careful and when to go for it2021In: Marine Pollution Bulletin, ISSN 0025-326X, E-ISSN 1879-3363, Vol. 167, article id 112321Article in journal (Refereed)
    Abstract [en]

    Harvesting of marine biomass for various applications may generate ecosystem services that currently lack a market price. One of these is nutrient uptake, which could counteract eutrophication. Market-based instruments (MBIs) such as cap & trade, compensatory mitigation, and payment for ecosystem services could help internalize such positive externalities. However, activities of the blue bioeconomy are diverse. We show that identifiable market characteristics can provide guidance concerning when to use these instruments and not. We find that the activities most suitable for MBIs are those that have positive environmental impacts but that are not (yet) financially viable. For activities that are already profitable on the biomass market, ensuring 'additionality' may be a significant problem for MBIs, especially for cap & trade systems or compensatory mitigation. We provide an overview of how some current biomass options fit into this framework and give suggestions on which biomass types to target.

  • 24.
    Hasselström, Linus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Thomas, Jean Baptiste E.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Nordström, J.
    Cervin, G.
    Nylund, G. M.
    Pavia, H.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Socioeconomic prospects of a seaweed bioeconomy in Sweden2020In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, no 1, article id 1610Article in journal (Refereed)
    Abstract [en]

    Seaweed cultivation is a large industry worldwide, but production in Europe is small compared to production in Asian countries. In the EU, the motivations for seaweed farming may be seen from two perspectives; one being economic growth through biomass production and the other being the provisioning of ecosystem services such as mitigating eutrophication. In this paper, we assess the economic potential of large-scale cultivation of kelp, Saccharina latissima, along the Swedish west coast, including the value of externalities. The findings suggest that seaweed farming has the potential of becoming a profitable industry in Sweden. Furthermore, large-scale seaweed farming can sequester a significant share of annual anthropogenic nitrogen and phosphorus inflows to the basins of the Swedish west coast (8% of N and 60% of P). Concerning the valuation of externalities, positive values generated from sequestration of nitrogen and phosphorus are potentially counteracted by negative values from interference with recreational values. Despite the large N and P uptake, the socioeconomic value of this sequestration is only a minor share of the potential financial value from biomass production. This suggests that e.g. payment schemes for nutrient uptake based on the socioeconomic values generated is not likely to be a tipping point for the industry. Additionally, seaweed cultivation is not a cost-efficient measure in itself to remove nutrients. Policy should thus be oriented towards industry development, as the market potential of the biomass will be the driver that may unlock these bioremediation opportunities.

  • 25.
    Hasselström, Linus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Anthesis Enveco AB, Barnhusgatan 4, bv, Stockholm, Sweden.
    Visch, W.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Nylund, G. M.
    Pavia, H.
    The impact of seaweed cultivation on ecosystem services - a case study from the west coast of Sweden2018In: Marine Pollution Bulletin, ISSN 0025-326X, E-ISSN 1879-3363, Vol. 133, p. 53-64Article in journal (Refereed)
    Abstract [en]

    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 way 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.

  • 26. Iital, Arvo
    et al.
    Brandt, Nils
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Loigu, Enn
    Kloga, Marija
    Impact of changes in nutrient inputs to the water quality of the shallow Haapsalu Bay, the Baltic Sea2010In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 12, no 8, p. 1531-1536Article in journal (Refereed)
    Abstract [en]

    This study evaluated the impact of socio-economic and lifestyle changes on nutrient loads and water quality in Haapsalu Bay, the Baltic Sea between 1995-1996 and 2003-2004. Monthly monitoring data of water quality in four rivers discharging to the bay and seawater at five sea stations were used. External input of TN to the bay remained almost unchanged during the study period despite of the somewhat higher riverine load that was explained by intensified agriculture. The TP input decreased by approximately 45% due to the decrease in river and point source loads. Point sources contribute about one-third of the P load to the bay. An overall decreasing gradient from the rivers to the mouth of the bay was observed both for TP and TN concentrations indicating probable removal of these elements from the water column along the east-west transect. In order to keep the TN/TP ratio within the range that suppresses eutrophication in the bay, further efforts must be implemented to reduce point source phosphorus load.

  • 27.
    Kotta, Jonne
    et al.
    Univ Tartu, Estonian Marine Inst, Maealuse 14, EE-12618 Tallinn, Estonia.;Tallinn Univ Technol, Estonian Maritime Acad, Kopli 101, EE-11712 Tallinn, Estonia..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Barboza, Francisco R.
    Univ Tartu, Estonian Marine Inst, Maealuse 14, EE-12618 Tallinn, Estonia..
    Assessing the potential for sea-based macroalgae cultivation and its application for nutrient removal in the Baltic Sea2022In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 839, p. 156230-, article id 156230Article in journal (Refereed)
    Abstract [en]

    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.

  • 28.
    Krizsan, Sophie J.
    et al.
    Swedish Univ Agr Sci, Dept Agr Res Northern Sweden, Umeå, Sweden..
    Hayes, Maria
    Teagasc Food Res Ctr, Food Biosci Dept, Dublin, Ireland..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Ramin, Mohammad
    Swedish Univ Agr Sci, Dept Agr Res Northern Sweden, Umeå, Sweden..
    O'Hara, Peter
    Atlantic Technol Univ, Dept Hlth & Nutr Sci, Sligo, Ireland..
    Kenny, Owen
    Atlantic Technol Univ, Dept Hlth & Nutr Sci, Sligo, Ireland..
    Characterization and in vitro assessment of seaweed bioactives with potential to reduce methane production2022In: FRONTIERS IN ANIMAL SCIENCE, ISSN 2673-6225, Vol. 3, article id 1062324Article in journal (Refereed)
    Abstract [en]

    This study collates compositional analysis of seaweeds data with information generated from in vitro gas production assays in the presence and absence of seaweeds. The aim was to assess and rank 27 native northern European seaweeds as potential feed ingredients for use to reduce methane emissions from ruminants. It provides information for use in future in vivo dietary trials concerning feed manipulation strategies to reduce CH4 emissions efficiently from domestic ruminants based on dietary seaweed supplementation. The seaweeds H. siliquosa and A. nodosum belonging to phylum Phaeophyta displayed the highest concentration of phlorotannins and antioxidant activity among the macroalgae giving anti-methanogenic effect in vitro, while this explanation was not valid for the observed reduction in methane when supplementing with C. filum and L. digitata in this study. D. carnosa and C. tenuicorne belonging to phylum Rhodophyta had the highest protein content among the macroalgae that reduced methane production in vitro. There were no obvious explanation from the compositional analysis conducted in this study to the reduced methane production in vitro when supplementing with U. lactuca belonging to phylum Chlorophyta. The strongest and most complete methane inhibition in vitro was observed when supplementing with Asparagopsis taxiformis that was used as a positive control in this study.

  • 29.
    Li, Ji
    et al.
    School of Oceanography, Shanghai Jiao Tong University, Shanghai 200030, China.
    Bergman, Kristina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Thomas, Jean-Baptiste
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gao, Yonghui
    School of Oceanography, Shanghai Jiao Tong University, Shanghai 200030, China.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Life Cycle Assessment of a large commercial kelp farm in Shandong, China2023In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 903, article id 166861Article in journal (Refereed)
    Abstract [en]

    The environmental benefits of seaweed cultivation have gained a lot of attention, both in policy strategies and by private companies. Sustainability evaluations of seaweed farming have however focused on a very small part of global production of seaweed - on European cultivations at research and pilot-scales although Asia stands for 99 % of global production with China alone producing 60 %. In this study, we use Life Cycle Assessment (LCA) to evaluate the environmental performance of a 400-hectare Chinese kelp farm with a yearly harvest of 60,000 tons. Primary data from the farm was used to assess impacts up until harvest for the functional unit of 1 ton of fresh-weight kelp. Included in the LCA were impact on climate change, acidification terrestrial and marine eutrophication, and use of land water and energy. In addition, we calculated nutrient uptake. Further, we extracted inventory data of four published LCA studies of farmed kelp and recalculated environmental impacts, applying the same background data and method choices with the aim to compare the effects of scale and cultivation system. The results of the hotspot analysis showed that the plastic ropes and buoys dominated impacts on climate change, freshwater and marine eutrophication, and energy consumption. Consequently, the most effective improvement action was recycling after use. The yearly harvest of the Chinese farm was 1000–4000 times larger than previously evaluated farms compared. Results suggest that streamlined and mature production in the large-scale Chinese kelp farm led to lower electricity and fuel consumption compared to small-scale production, thus placing the Chinese farm with a climate impact of 57.5 kg CO2 eq. per ton fresh-weight kelp on the lower end when comparing the carbon footprint. There was a large variation in carbon footprints, which implies that the kelp cultivation sector has considerable room for optimization.

  • 30.
    Nathaniel, Hanna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Franzén, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Regional variations in the chemical composition of fresh and composted beachcast on the island of Gotland, Sweden – considering future treatmentsManuscript (preprint) (Other academic)
    Abstract [en]

    Harvesting beachcast from coastal zones to use the biomass in agriculture or horticulture could mitigate eutrophication while contributing to resource substitution of fossil-based inputs in food production. As such, beachcast holds great resource potential in a bio-based circular economy, but its chemical properties prove challenging, and more research is required to develop treatment techniques that will allow the realisation of such a system. We compiled results from chemical analyses of fresh beachcast from a database within the marine policy scheme, LOVA, in Gotland, Sweden, to study local and seasonal variations in macronutrients, C:N ratio, and Cd content. This data complemented with analyses of fresh and composted beachcast (passive pile treatment), for which the contents of macronutrient, ammonium, nitrate, and Cd, were measured, calculating C:N ratios and maturity indices (NH4+-N/NO3—N). The results confirm that regional variations in the above-mentioned properties require investments in treatment techniques and strategies to make beachcast usable. 

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  • 31.
    Nathaniel, Hanna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Franzén, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Lingegård, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Franzen, Frida
    Tyrens AB, Peter Myndes Backe 16, SE-11846 Stockholm, Sweden..
    Soderqvist, Tore
    Holmboe & Skarp AB, Norr Kallstavagen 9, SE-14896 Sorunda, Sweden..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Using stakeholder perceptions to deepen the understanding of beachcast governance and management practices on Gotland, Sweden2023In: Ocean and Coastal Management, ISSN 0964-5691, E-ISSN 1873-524X, Vol. 239, article id 106583Article in journal (Other academic)
  • 32.
    Nathaniel, Hanna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, SE-750 07, Uppsala, Sweden.
    Franzén, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Cd accumulation in soil from beachcast application: A long-term prediction of its reintroduction for bio-fertilisation in Gotland, SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    The ecological consequences of using beachcast compost as an agricultural resource input merit study. Using beachcast compost as a biofertiliser has multiple positive effects on agroecosystems, while also serving to remedy the negative effects on marine ecosystems caused by excessive beachcast production due to eutrophication. This process thus presents an opportunity to contribute to circular nutrient management and the development of sustainable agricultural, but it may also result in accumulation Cd (Cd) in the soil. In Gotland, Sweden, an example of cross-scale interaction between marine and agricultural domains has emerged from a national policy subsidising beachcast harvesting, which may help reintroduce the historical tradition of using beachcast in agriculture. To estimate potential risks, a field experiment and Cd mass balance were conducted to predict the rate of Cd accumulation, changes in soil Cd fractions, and potential beachcast application methods that avoid Cd soil accumulation. In the scenario where the maximum Cd input from beachcast compost is set to the same threshold as the level established for sewage sludge—0.75 g ha–1 year–1—beachcast compost with a Cd content of 1.5 mg kg–1 dw (the EU threshold for biofertilisers) could be applied in an amount of approximately 2000 kg ha–1 per year (one-tenth of the amount applied in this study). Therefore, the long-term effects of Cd soil accumulation resulting from continuous application of beachcast as fertiliser on agroecosystems cannot be disregarded and are of global relevance. 

     

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  • 33.
    Pechsiri, Joseph Santhi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ganguly, Srirupa
    University of Illinois.
    Ng, T.Y.S
    University of Illinois.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Malmström, Maria
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Preliminary assessment of simultaneous mixotrophic production of Tetraselmis tetrathele and treatment of saline wastewater from aquacultureManuscript (preprint) (Other academic)
    Abstract [en]

    Interest in industrial-scale cultivation of microalgae biomass has increased in recent years, due to its potential in phytochemicals, wastewater treatment, and aquaculture feed. Previous studies have focused on freshwater systems and phototrophic microalgae growth. In this study, preliminary observations were performed on mixotrophic growth of Tetraselmis tetrathele in crude unaltered saline wastewater and its nutrient removal and aquaculture feed potential. The wastewater was obtained directly from a Pacific white shrimp farm. The results showed successful phototrophic and mixotrophic growth of Tetraselmis tetrathele in saline wastewater, with maximum specific growth rate of approximately 0.2 day-1. Some nutrient removal was achieved (phosphate), and use of biomass as feed for shrimp aquaculture are further discussed.

  • 34.
    Pechsiri, Joseph Santhi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Assessing energy return on investment for harvest of wild Nodularia spumigena during blooms in the Baltic Sea2021In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290Article in journal (Refereed)
    Abstract [en]

    Recurring summer cyanobacteria blooms in the Baltic Sea has gained academic interests for decades. The harvest of wild cyanobacteria, for example, Nodularia spumigena, during summer blooms in the Baltic Sea has been studied in the past but lacked evaluation for environmental and economic performances. This study provides a first-hand assessment of environmental and economic performance from an energy perspective, using energy return on investment (EROI) as evaluation method where harvest of biomass and the downstream conversion of biomass to biogas and biofertilizer are considered for Gotland, Sweden. Energy analysis results indicate fuel consumption during harvest and transport operations to be the major energy consumer. Traditional sailing boats have been suggested as an alternative. Overall, when considering only biogas yield and usage of sailing boats, a break-even EROI of 1 is achieved. When including biofertilizer as product, a breakeven EROI of 1 is also achieved. Depending upon the biomass concentration in the Baltic Sea at the time of harvest, an EROI > 6 is possible, surpassing the economic viability EROI benchmark of 3, indicating the importance of nutrient recovery as the driver for harvest of wild cyanobacteria biomass during blooms in the Baltic Sea. This article met the requirements for a gold-gold JIE data openness badge described at http://jie.click/badges. 

  • 35.
    Pechsiri, Joseph Santhi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Risén, Emma
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Malmström, Maria E.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Brandt, Nils
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Harvesting of Nodularia spumigena in the Baltic Sea: Assessment of Potentials and Added Benefits2014In: Journal of Coastal Research, ISSN 0749-0208, E-ISSN 1551-5036, Vol. 30, no 4, p. 825-831Article in journal (Refereed)
    Abstract [en]

    Interest to harvest wild cyanobacteria exists due to the environmental and socioeconomic risks during cyanobacteria blooms coupled with demands for nonterrestrial-based alternatives for biofuel sources. This research, therefore, sought to estimate the wild cyanobacteria harvesting potential using Nodularia spumigena, and using the Baltic Sea as the case study. Data from literature provided during years 2003-2009 were used to perform estimations. Additional benefits of harvesting were also assessed by estimating the nutrient removal and biogas production potentials from the harvested biomass. Results indicate that one boom unit has the potential to harvest approximately 3 to 700 kg dry weight of N. spumigena per hour depending on the algae concentration of the bloom. Results also suggest that nutrient removal and biogas production potentials provide substantial additional incentives to the harvesting operation during years of extensive and highly concentrated blooms. However, during nonextensive or nonconcentrated blooms such potentials are low.

  • 36.
    Pechsiri, Joseph Santhi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Song, X
    Faculty of Biosciences, Fisheries and Economics, The Arctic University of Norway, 9037 Tromsø, Norway.
    Malmström, Maria
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Cheng, Jun
    State Key Laboratory of Clean Energy Utilization, Zhejiang University, 310027 Hangzhou, PR China.
    Cen, Kefa
    State Key Laboratory of Clean Energy Utilization, Zhejiang University, 310027 Hangzhou, PR China.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Energy Analysis of the Nannochloropsis sp. Production as an Alternative Protein Source using the Holistic ep-EROIManuscript (preprint) (Other academic)
    Abstract [en]

    Energy systems analysis and greenhouse gas (GHG) emissions of open pond microalgae cultivation systems is attracting considerable interest in the past decade due to their potentials for the production of biofuels and phytochemicals. However, there has been little discussion on energy systems analysis of microalgae produced from power plant flue gas and its use as an alternative protein source. This study aims to analyze edible protein energy return on investment (ep-EROI) and the overall GHG emissions for a medium-to-large scale Nannochloropsis oceanica cultivation system using power plant flue gas in northern China. Besides, additional benefits of the microalgae cultivation system were assessed on the overall nutrient recovery potential of the harvested biomass. Results of the study indicated that cumulative energy demand and GHG emissions for production of Nannochloropsis oceanica products were intermediate to other conventional protein sources in the literature, such as fish. Results of the EROI-based analysis showed that the Nannochloropsis oceanica cultivation system achieved a moderate ep-EROI of 0.11.

  • 37.
    Pechsiri, Joseph Santhi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Thomas, Jean Baptiste E.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Risén, Emma
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology. Currently at Sweco Environment AB, Sweden.
    Ribeiro, Mauricio S.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Malmström, Maria E.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Nylund, G. M.
    Jansson, A.
    Welander, U.
    Pavia, H.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Energy performance and greenhouse gas emissions of kelp cultivation for biogas and fertilizer recovery in Sweden2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 573, p. 347-355Article in journal (Refereed)
    Abstract [en]

    The cultivation of seaweed as a feedstock for third generation biofuels is gathering interest in Europe, however, many questions remain unanswered in practise, notably regarding scales of operation, energy returns on investment (EROI) and greenhouse gas (GHG) emissions, all of which are crucial to determine commercial viability. This study performed an energy and GHG emissions analysis, using EROI and GHG savings potential respectively, as indicators of commercial viability for two systems: the Swedish Seafarm project's seaweed cultivation (0.5 ha), biogas and fertilizer biorefinery, and an estimation of the same system scaled up and adjusted to a cultivation of 10 ha. Based on a conservative estimate of biogas yield, neither the 0.5 ha case nor the up-scaled 10 ha estimates met the (commercial viability) target EROI of 3, nor the European Union Renewable Energy Directive GHG savings target of 60% for biofuels, however the potential for commercial viability was substantially improved by scaling up operations: GHG emissions and energy demand, per unit of biogas, was almost halved by scaling operations up by a factor of twenty, thereby approaching the EROI and GHG savings targets set, under beneficial biogas production conditions. Further analysis identified processes whose optimisations would have a large impact on energy use and emissions (such as anaerobic digestion) as well as others embodying potential for further economies of scale (such as harvesting), both of which would be of interest for future developments of kelp to biogas and fertilizer biorefineries.

  • 38.
    Pechsiri, Joseph Santhi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Thomas, Jean-Baptiste
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    El Bahraoui, Naoufel
    Mines ParisTech, Ctr Energy Efficiency & Syst, 60 Bd St Michel, F-75272 Paris, France.;Setec Energie Environm, 42-52 Quai Rapee, F-75012 Paris, France..
    Acien Fernandez, Francisco Gabriel
    Univ Almeria, Dept Chem Engn, Canda San Urbano S-N, Almeria 04120, Spain..
    Chaouki, Jamal
    Polytech Montreal, 2500 Chem Polytech, Montreal, PQ H3T 1J4, Canada..
    Chidami, Saad
    Polytech Montreal, 2500 Chem Polytech, Montreal, PQ H3T 1J4, Canada..
    Tinoco, Rodrigo Rivera
    Mines ParisTech, Ctr Energy Efficiency & Syst, 60 Bd St Michel, F-75272 Paris, France..
    Pena Martin, Jose
    Univ Almeria, Dept Chem Engn, Canda San Urbano S-N, Almeria 04120, Spain..
    Gomez, Cintia
    Univ Almeria, Dept Chem Engn, Canda San Urbano S-N, Almeria 04120, Spain..
    Combe, Michel
    Setec Energie Environm, 42-52 Quai Rapee, F-75012 Paris, France..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Comparative life cycle assessment of conventional and novel microalgae production systems and environmental impact mitigation in urban-industrial symbiosis2023In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 854, article id 158445Article in journal (Refereed)
    Abstract [en]

    The versatility of microalgae biomass as candidates for various products and bioremediation needs motivates interests towards design and implementation of novel microalgae bioreactors. Conventional open-reactors are reliant on large quantities of sunlight and space while yields are constrained by outdoor environment conditions. Conversely, closed-reactor systems like bubble columns reduces these constrains on microalgae growth while occupying far less space at the expense of high energy demands, notably from lighting systems. A novel patented closed reactor design has recently been proposed that improves the bubble column concept with an efficient and effective lighting system. The present study uses Life Cycle Assessment approach to compare the environmental performance of conventional reactors and the proposed internally luminated novel closed reactor design, expressing impacts per kg biostimulant for the Scenedesmus almeriensis harvest from such units. All performance data was collected from a pilot facility in Almeria, Spain. Urban-industrial symbiosis scenarios are also portrayed in the study using wastewater and incinerator flue gas. Results show that under synthetic nutrient and carbon inputs in Spanish pilot operations, the cumulative energy demand for the novel photobioreactors is similar to conventional vertically-stacked horizon bioreactors but are substantially more demanding than conventional open reactors. However, when leveraging renewable energy sources and the photosynthesis process to consume wastestreams in urban-industrial symbiosis scenarios, the novel photobioreactor was able to achieve up to 80 % improvements in several impact categories e.g. eutrophication and climate change. Impact mitigation credits per kg dwt biomass across all energy scenarios in symbiosis amount to asymptotic to 1.8 kg CO(2)eq and asymptotic to 0.09 kg PO4 eq. This highlights that such closed and internally illuminated photobioreactors can be competitive with conventional reactors, and have potential to harness photosynthesis to reduce environmental burdens in an urban-industrial symbiosis setting. Possible economies of scale and the associated potential gains in efficiencies are further discussed.

  • 39.
    Potting, José
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Thomas, Jean-Baptiste
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Stakeholder participation in sustainability assessment of non-wicked problems: The case of a future seaweed industry in Sweden2021In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209Article in journal (Refereed)
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  • 40. Risén, E.
    et al.
    Nordström, J.
    Malmström, Maria
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Non-market values of algae beach-cast management – Study site Trelleborg, Sweden2017In: Ocean and Coastal Management, ISSN 0964-5691, E-ISSN 1873-524X, Vol. 140, p. 59-67Article in journal (Refereed)
    Abstract [en]

    Eutrophication is one of the most serious global threats to coastal areas. One effect of eutrophication is seasonal macroalgal blooms. As a consequence, large amounts of beach-cast algae are today reported from coastal areas worldwide. In this study, we analyze nonmarket benefits by capturing local residents’ Willingness To Pay (WTP) for an environmental program to regularly remove and utilize beach-cast algae to produce bioenergy and biofertilizer. Results indicate a considerable WTP among local residents in the Baltic Sea study site. This WTP estimate together with a potential increase in non-resident beach tourism amounts to potentially substantial welfare benefits from the environmental program. These benefits could encourage similar environmental programs in the future.

  • 41.
    Risén, Emma
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Brandt, Nils
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Malmström, Maria
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Sustainable production of biogas from maritime biomass2010Report (Other academic)
  • 42.
    Risén, Emma
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Gregeby, Erik
    Tatarchenko, Olena
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Blidberg, Eva
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Malmström, Maria E.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Welander, Ulrika
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Assessment of biomethane production from maritime common reed2013In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 53, p. 186-194Article in journal (Refereed)
    Abstract [en]

    Several ongoing projects are harvesting maritime biomass from the Baltic Sea for eutrophication mitigation and utilisation of the recovered biomass. Some of this biomass comprises common reed (Phragmites australis), one of the most widespread vascular plants on Earth. Reed utilisation from eutrophied coastal areas needs to be evaluated. Therefore, a system analysis was performed of reed harvesting for biofuel and biofertiliser production. The specific objectives of the analysis were to: investigate the methane yield associated with anaerobic co-digestion of reed; make a primary energy assessment of the system; quantify Greenhouse Gas (GHG) savings when a fossil reference system is replaced; and estimate the nutrient recycling potential of the system. The results from energy and GHG calculations are highly dependent on conditions such as system boundaries, system design, allocation methods and selected indicators. Therefore a pilot project taking place in Kalmar County, Sweden, was used as a case study system. Laboratory experiments using continuously stirred tank reactor digesters indicated an increased methane yield of about 220 m(3) CH4/t volatile solids from co-digestion of reed. The energy balance for the case study system was positive, with energy requirements amounting to about 40% of the energy content in the biomethane produced and with the non-renewable energy input comprising about 50% of the total energy requirements of the system. The net energy value proved to be equivalent to about 40 L of petrol/t reed wet weight. The potential to save GHG emissions compared with a fossil reference system was considerable (about 80%). Furthermore an estimated 60% of the nitrogen and almost all the phosphorus in the biomass could be re-circulated to arable land as biofertiliser. Considering the combined benefits from all factors investigated in this study, harvesting of common reed from coastal zones has the potential to be beneficial, assuming an appropriate system design, and is worthy of further investigations regarding other sustainability aspects.

  • 43.
    Risén, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Nordström, Jonas
    Lund University.
    Malmström, Maria E.
    Gröndahl, Fredrik
    Valuing beach cast utilization and addressing preference uncertaintyManuscript (preprint) (Other academic)
    Abstract [en]

    Eutrophication and global warming have created major problems with decaying macroalgae on Baltic Sea beaches. A considerable amount of this biomass is retrieved, only to be returned to the sea when the tourist season ends. It is therefore essential to implement systems whereby the retrieved biomass is utilised. One potential system is anaerobic digestion for biogas and biofertiliser recovery, but knowledge about non-market benefits is lacking. This study estimated the willingness-to-pay (WTP) for algae retrieval and utilisation in a case study area and examined methods for incorporating preference uncertainty information into WTP estimates. This was done by gathering data using two different methods and comparing the results. In addition, results obtained from an open-ended interval (OEI) format were compared with those from a payment card. A substantial mean WTP was found. The two elicitation formats produced similar mean WTP estimates. However, the OEI format produced weaker results, with a significantly higher level of stated preference uncertainty and an elevated zero response rate. Comparisons of preference uncertainty information gathered with two different methods yielded unexpected results and to some extent contradicted findings on interval size in the OEI format as a good measure of preference uncertainty.

  • 44.
    Risén, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Pechsiri, Joseph Santhi
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Malmström, Maria
    Brandt, Nils
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Natural Resource Potential of Macroalgae Harvesting in the Baltic Sea-Case Study Trelleborg, Sweden2013In: Global Challenges in Integrated Coastal Zone Management, John Wiley & Sons, 2013, p. 69-84Chapter in book (Other academic)
    Abstract [en]

    The interest in harvesting biomass from the Baltic Sea has increased in recent years. However, there is a lack of available data on macroalgae biomass and of cost-effective methods for site-specific quantification of macroalgae. In this study, macroalgae biomass has been quantified in Trelleborg and thus the nutrient reduction that could be achieved by harvesting on a regional scale. The biomass was estimated on the basis of existing inventories of macroalgae, photic zone distribution and bottom substrata. An independent model for estimating the potential of macroalgae growth was applied where factors affecting the growth of macroalgae, for example nutrients, light and temperature, were considered. The estimated summer stock of macroalgae biomass along the 58 km coastal stretch in Trelleborg amounts to 19 000 tonnes dry weight (dwt) red filamentous algae. If 10-30% of this summer stock were to be harvested, a nutrient reduction of 50-150 t of nitrogen could be achieved. The model for estimating biomass proved promising and worthy of further investigation.

  • 45.
    Risén, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Tatarchenko, Olena
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Malmström, Maria E.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Harvesting of drifting filamentous macroalgae in the Baltic Sea: An energy assessment2014In: Journal of Renewable and Sustainable Energy, E-ISSN 1941-7012, Vol. 6, no 1, p. 013116-Article in journal (Refereed)
    Abstract [en]

    Eutrophication combined with climate change has caused ephemeral filamentous macroalgae to increase and drifts of seaweed cover large areas of some Baltic Sea sites during summer. In ongoing projects, these mass occurrences of drifting filamentous macroalgae are being harvested to mitigate eutrophication, with preliminary results indicating considerable nutrient reduction potential. In the present study, an energy assessment was made of biogas production from the retrieved biomass for a Baltic Sea pilot case. Use of different indicators revealed a positive energy balance. The energy requirements corresponded to about 30%-40% of the energy content in the end products. The net energy gain was 530-800 MJ primary energy per ton wet weight of algae for small-scale and large-scale scenarios, where 6 000 and 13 000 tonnes dwt were harvested, respectively. However, the exergy efficiency differed from the energy efficiency, emphasising the importance of taking energy quality into consideration when evaluating energy systems. An uncertainty analysis indicated parametric uncertainty of about 25%-40%, which we consider to be acceptable given the generally high sensitivity of the indicators to changes in input data, allocation method, and system design. Overall, our evaluation indicated that biogas production may be a viable handling strategy for retrieved biomass, while harvesting other types of macroalgae than red filamentous species considered here may render a better energy balance due to higher methane yields.

  • 46.
    Sinha, Rajib
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Thomas, Jean-Baptiste
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Strand, A.
    IVL Svenska Miljoinst, IVL Swedish Environm Res Inst, Kristineberg 566, S-45178 Fiskebackskil, Sweden..
    Soderqvist, T.
    Anthesis Enveco AB, Barnhusgatan 4, SE-11123 Stockholm, Sweden.;Holmboe & Skarp AB, Norr Kallstavagen 9, SE-14896 Sorunda, Sweden..
    Stadmark, J.
    IVL Svenska Miljoinst, IVL Swedish Environm Res Inst, POB 53021, S-40014 Gothenburg, Sweden..
    Franzen, F.
    Tyrens AB, Peter Myndes Backe 16, SE-11846 Stockholm, Sweden..
    Ingmansson, I.
    Tyrens AB, Peter Myndes Backe 16, SE-11846 Stockholm, Sweden..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Hasselström, Linus
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Quantifying nutrient recovery by element flow analysis: Harvest and use of seven marine biomasses to close N and P loops2022In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 178, article id 106031Article in journal (Refereed)
    Abstract [en]

    Anthropogenic consumption of nitrogen (N) and phosphorus (P) has pushed their respective planetary boundaries beyond a safe operating space causing environmental problems, and simultaneously, the depletion of finite mineral P resources is of growing concern. Previous research has found that marine biomass such as kelp, reed and mussels have a high potential for taking up N and P, which could potentially contribute both to alleviating environmental problems and recirculating P from marine environments back to human consumption systems. This paper thus examines these nutrient flows and the extent to which marine biomass can contribute to close the loop. The study utilizes an element flow analysis (EFA) to establish the mapping of N and P flows and explore plausible scenarios of biomass utilisation by 2030 and 2050 for P loop closure in Sweden. The current uptake of P and N through the seven marine biomass cases (mariculture of mussels on both the Swedish east and west coasts, kelp and ascidians and the harvest of wild oysters, beach-cast and reed) contributes to 1.1% and 0.3% respectively of the full loop closure (relative to 2016 loading). Approximately 22% of the total P (and 23% N) uptake (in the biomasses) is currently being used in products, while the rest remains unused. The plausible future scenario for 2050 expects to contribute to around 10% P and 2.8% N loop closure (relative to 2016) if all nutrients in the uptake are used.

  • 47. Sjöåsen, T.
    et al.
    Bisther, M.
    Gröndahl, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Evaluation of an Otter (Lutra lutra)2009Article in journal (Other academic)
  • 48.
    Stenius, Ivan
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics.
    Folkesson, John
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Bhat, Sriharsha
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics.
    Sprague, Christopher Iliffe
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Ling, Li
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Özkahraman, Özer
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Bore, Nils
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Cong, Zheng
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Severholt, Josefine
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics.
    Ljung, Carl
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics.
    Arnwald, Anna
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics.
    Torroba, Ignacio
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Robotics, Perception and Learning, RPL.
    Gröndahl, Fredrik
    Thomas, Jean-Baptiste
    A system for autonomous seaweed farm inspection with an underwater robot2022In: Sensors, E-ISSN 1424-8220, Vol. 22, no 13, article id 5064Article in journal (Refereed)
    Abstract [en]

    This paper outlines challenges and opportunities in operating underwater robots (so-called AUVs) on a seaweed farm. The need is driven by an emerging aquaculture industry on the Swedish west coast where large-scale seaweed farms are being developed. In this paper, the operational challenges are described and key technologies in using autonomous systems as a core part of the operation are developed and demonstrated. The paper presents a system and methods for operating an AUV in the seaweed farm, including initial localization of the farm based on a prior estimate and dead-reckoning navigation, and the subsequent scanning of the entire farm. Critical data from sidescan sonars for algorithm development are collected from real environments at a test site in the ocean, and the results are demonstrated in a simulated seaweed farm setup.

  • 49.
    Sterner, Martin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Extraction of laminarin from Saccharina latissima seaweed using cross-flow filtration2021In: Journal of Applied Phycology, ISSN 0921-8971, E-ISSN 1573-5176, Vol. 33, no 3, p. 1825-1844Article in journal (Refereed)
    Abstract [en]

    Laminarin is a low-molecular-weight polysaccharide found in seaweed (kelp), often in equal concentrations to that in the commercially important hydrocolloid alginate. However, while alginate can be easily recovered by dissolution followed by acid precipitation, for laminarin, there is no such straightforward way of recovering it. Laminarin can be used as dietary fiber and, if efficiently extracted, it may be used for functional food/feed applications and as a component in plant defense stimulants for agriculture. One way of concentrating laminarin from dilute solutions is to press the solution through ultrafine membranes that the molecules cannot pass through. When alginate is extracted, an acid pretreatment step is used and the dilute acid residue from that process also contains laminarin. We used cross-flow filtration to concentrate laminarin from Saccharina latissima, retrieving it from the dilute acid solution of the acid pretreatment of an alginate extraction. Three ceramic membranes with 5, 15, and 50 kDa molecular weight cutoffs were used, and the pressure, temperature, and feed velocity were altered to reveal which parameters controlled the flow through the membrane and how efficiently laminarin was concentrated. The effects on laminarin extraction for fresh vs. frozen biomass were evaluated showing that frozen biomass releases more laminarin with a similar biomass homogenization technique. Thermal and microbial degradation of the feed components was studied during the course of the filtrations, showing that microbial degradation can affect the laminarin concentration, while the temperature of the process ~ 65 °C had little impact on laminarin. The techniques used to monitor the components in the feed and permeate during filtration were nuclear magnetic resonance, 1H-NMR, and size exclusion chromatography. The filtrations were performed in a pilot-size filtration unit with ceramic membranes (ZrO2/TiO2, TiO2-Al2O support, 0.08 m2). To be able to operate without quick membrane fouling, the most important parameter was to have a high liquid velocity over the membrane, 4.7 m s−1. A good technique to concentrate laminarin was to prefilter it through a 50-kDa membrane using 2 bar liquid pressure and to concentrate it over a 5-kDa membrane using 5-bar liquid pressure. With these settings, the liquid flux through the filter became 60–80 and 30–40 L m−2 h−1 over the 50-kDa and 5-kDa membrane.

  • 50.
    Sterner, Martin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Ribeiro, Mauricio Sodre
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Edlund, Ulrica
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Cyclic fractionation process for Saccharina latissima using aqueous chelator and ion exchange resin2017In: Journal of Applied Phycology, ISSN 0921-8971, E-ISSN 1573-5176, Vol. 29, no 6, p. 3175-3189Article in journal (Refereed)
    Abstract [en]

    A new approach to process Saccharina latissima algal biomass was developed using sodium citrate and a polyvalent cation-specific resin to sequentially extract the alginate into several usable fractions. The fractionation was performed in a cyclic manner, utilizing a stepwise removal of the native polyvalent ions present in the algae to isolate fractions of alginate with different solubility in the presence of these ions. Sodium citrate was used in different concentrations in the extraction solution to remove polyvalent cations to adjust the alginate liberation while AMBERLITE IRC718 resin was added to further remove these ions and regenerate the extraction solution. Alginate was recovered by acid precipitation and analyzed for its uronic acid composition and molecular weight, and the carbohydrate compositions of the insoluble and soluble parts of the algal biomass residue were determined. Finally, the fractionation method was assessed with a life cycle analysis to determine the energy and water efficiency as well as the greenhouse gas emissions and the results were compared to conventional alkaline extraction. The results indicate that the energy and water use as well as the emissions are considerably lower for the cyclic extraction in comparison with the conventional methods.

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