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- Luthman, Ola
(författare)
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Searching for sustainable aquaculture governance : A focus on ambitions and experience
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aquaculture is one of the most diverse food-producing industries and is suggested as a key solution to a growing global food demand. It has been argued that aquaculture has the potential to expand sustainably in most parts of the world, especially in the EU where consumption far out weighs production. This positive view surrounding aquaculture’s growth emphasizes its positive social and ecological effects. These include the generation of rural employment opportunities and the production of nutrient-dense food with negligible or even beneficial environmental effects (e.g. nutrient sequestration). However, for the industry to fulfil this potential, it needs informed governance structures and policies about social-ecological systems that are sensitive to local issues and conditions but also linked to the wider transnational/global context. This thesis provides empirical insight into how different levels of governance and policy interact and the ‘sustainability aquaculture development’ that different actors advocate. By using the Social-Ecological Systems (SES) approach as the theoretical foundation, combined with discourse and policy analyses, this thesis delves into how sustainability is framed in different aquaculture governance settings to give nuanced insights into varied sustainability discourses. This includes examining some of the most influential governing actors in the global North, ranging from intergovernmental organizations (IGOs) like the EU and UN to states and certification organizations.Based on academic and international governing goals for expanding aquaculture sustainably through multi-stakeholder engagements, and the rapid expansion of Atlantic salmon production, this thesis analyzes how alternative influential governance regimes, like certification programs, compare in terms of environmental stringency with the national regulatory standards of the largest salmon-producing states. One region of interest in this thesis is the Nordics where aquaculture production is unevenly distributed. Norway is one of the most prominent global aquaculture production countries; other states such as Iceland are growing rapidly while countries around the Baltic Sea have very little production. Aquaculture in the Nordics is mostly centered around resource-intensive species with a high market value like Atlantic salmon. Continuing with the ambition to use multi-stakeholder engagements, this thesis also provides empirical insight into how policies and legislation are formed to promote aquaculture. Finally, based on global and regional recognition that food production needs to decrease its dependence on antibiotics, this thesis looks at how some of the most impactful aquaculture markets globally regulate antibiotics usage in aquaculture operations.This thesis contributes by developing a conceptual framework to examine how different aspects of sustainability are aspired to and pursued in different aquaculture governance arrangements and settings. Through the application of this framework, the thesis develops critical insights into how governing actors frame sustainable aquaculture, identifying dissonances and synergies between international and national ambitions and making suggestions for how aquaculture sustainability can be improved.
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- Lilliesköld Sjöö, Gustaf, 1981-
(författare)
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Macroalgae in tropical seascapes : regulating factors and functions in the coastal ecosystem
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Although macroalgae usually are inconspicuous on pristine coral reefs, they often thrive on reefs that are subjected to various types of anthropogenic disturbance. This thesis consists of five papers and investigates how biomass and composition of macroalgal communities on coral reefs are affected by regulating factors, such as nutrient availability, herbivory, substrate availability and hydrodynamic forces. In addition, ecological functions and potential impacts of both wild and farmed macroalgal communities are evaluated. Paper I describes a method for using macroalgal tissue nutrient concentrations as bioindicator for nutrient availability, with the possibility to map nutrient loading from larger coastal cities. Papers II and III are manipulative studies comparing top-down and bottom-up regulation of macroalgal communities, where herbivore consumption seems to be the main regulator of biomass whereas nutrient availability mainly influences community composition. Exclosure of large-bodied herbivores had a positive influence on algal biomass in both studies, and during different climatic periods. Paper III also includes the influence of hydrodynamic forces on algal community biomass and structure by comparing a reef crest and a back reef-habitat. Alterations of top-down and bottom-up regulation generally had a stronger effect within the protected back reef-habitat, suggesting that such environments may be more sensitive to anthropogenic influence. Paper IV confirms the general conclusions from papers II and III by studying macroalgal biomass and composition on reef sites with different environmental prerequisites. This study also supports the notion that herbivorous fish can suppress accumulation of macroalgal biomass if substrate availability is low, but not where coral cover is reduced and plenty of substrate is open to macroalgal colonization. The study also found a large temporal variation of macroalgal standing stock and associated nutrients at sites with low top-down regulation. Paper V evaluates potential impacts of seaweed farming on coral reefs and nutrients in the seascape by experimentally studying growth, survival and nutrient binding capacity of Eucheuma denticulatum. This study showed that seaweed farms counteract eutrophication through nutrient extraction and that the risk of farmed algae colonizing local reefs seems to be small as they were rapidly consumed. In conclusion, the studies in this thesis contribute to the understanding of macroalgal regulation and function in tropical seascapes, thereby adding to the knowledge base for coastal management.
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- Mirera, David Oersted, 1975-
(författare)
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Capture-based mud crab (Scylla serrata) aquaculture and artisanal fishery in East Africa- Practical and ecological perspectives : Mud crab ecology and aquaculture
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mud crab Scylla serrata is a crustacean that spends most of its life cycle in the mangrove environment throughout its range. Fishery and aquaculture of this crab are significant economic activities in coastal areas in the tropics and sub-tropics because of the meat quality and nutritional value. However there is a significant shortage of information on the ecology, fishery and aquaculture of these crabs in sub-Saharan Africa. This impacts the development of a sustainable aquaculture and fishery for the benefit of coastal communities. The present study analyses various aspects of mud crab ecology, fishery, aquaculture and social economics in East Africa using multidisciplinary approaches. The results are given in seven papers based on field and laboratory studies. The study established for the first time that high intertidal mangrove back-flats constitute a key habitat for the earliest instars of S. serrata (4 -30 mm CW). It also showed that diurnal tidal migration behaviour occurs in small juveniles that migrate to sub-tidal habitats during the day, possibly due to variable predation risks. Monthly sampling of juveniles in Kenya and Tanzania indicated continuous recruitment throughout the year. The large numbers of juvenile crabs along mangrove fringes indicate that these habitats could serve as sites suitable for collection of juvenile crabs for aquaculture. However, these areas must also be managed and protected to support the recruitment to the wild crab populations. An assessment of the crab fishery indicated that artisanal crab fishers possess significant traditional knowledge mainly inherited from their parents that enabled them to exploit the resource. Such knowledge could be useful for the development of the aquaculture and in management of the fishery. Mud crab fishing was found to be a male dominated activity, and fishers on foot practiced fishing in burrows at spring low tides. Interviews indicated that the average size of marketable crabs has declined over the years and a weak management system was observed with most fishers operating without a license. Due to the knowledge required regarding the local conditions, fishers are unable to shift to new areas. Furthermore fishers and could not fish at neap tides. Such limitations provide a “natural closure” of the fishery. Also foot fishers cover fairly limited distances in their daily operations, an aspect that can be utilized to effect site-specific management for the fishery if necessary. Laboratory and field experiments indicated that cannibalistic interactions are heavily influenced both by size differences of crabs and the availability of shelter but no significant effect was found for different stocking densities. Such information is of direct importance for crab farmers in East Africa, where seed from the wild are of multiple sizes and there is a need to grade juvenile crabs and provide shelter at stocking to ensure maximum survival. Experimental studies in earthen pond and mangrove pen cultures indicated high mortality rates. Comparing growth in earthen pond and mangrove pen systems indicated that growth rates were generally high in both systems, but significantly lower in pen systems without shelter, suggesting that shelter may have a stronger effect on growth than has been previously thought. Similar to artisanal mud crab fishery, an assessment of small-scale mud crab farming by organized community groups in Kenya indicated low level of women participation. A good knowledge of the market existed among the mud crab farming groups where hotels and exporters offered the highest prices. However there is a need for national policies to be directed to support small-scale aquaculture development by ensuring training and capacity building for women, operation and management of groups, data management and provision of user rights for communities working in the mangrove environment. Market analyses showed that the common market size of crabs in East Africa ranged between 500-1000 g and are thus larger than in Southeast Asia where the average size is reported at 300 g. Prices for mud crabs were over 50 % lower in Tanzania than in other East African countries and most of the profit was earned by middlemen and exporters. Cost revenue analysis showed that it would be more profitable to farm smaller commercial crabs, and develop a market for 300 g crabs to increase the profitability of crab farming in East Africa. Also, the same analyses found that farming large crabs in individual cages, which is the dominant culture form in East Africa today, had very low profitability due to high labor costs and low growth rates. Using a step-wise function of natural growth it was shown that growth rates of S. serrata cultured in cages was 40 % of the growth rates obtained in experimental pond and pen cultures, which were similar to natural growth. Therefore the good performance of grow-out cultures of juvenile mud crabs in earthen ponds and mangrove pens showed a potential to develop into a profitable and sustainable intervention. However, more work is needed to improve survival in culture systems and address the identified limitations of crab seeds and feed to enable development of sustainable mud crab aquaculture in East Africa.
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- Deutsch, Lisa, 1965-
(författare)
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Global trade, food production and ecosystem support : Making the interactions visible
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Modern food production is a complex, globalized system in which what we eat and how it is produced are increasingly disconnected. This thesis examines some of the ways in which global trade has changed the mix of inputs to food and feed, and how this affects food security and our perceptions of sustainability. One useful indicator of the ecological impact of trade in food and feed products is the Appropriated Ecosystem Areas (ArEAs), which estimates the terrestrial and aquatic areas needed to produce all the inputs to particular products.The method is introduced in Paper I and used to calculate and track changes in imported subsidies to Swedish agriculture over the period 1962-1994. In 1994, Swedish consumers needed agricultural areas outside their national borders to satisfy more than a third of their food consumption needs. The method is then applied to Swedish meat production in Paper II to show that the term “Made in Sweden” is often a misnomer. In 1999, almost 80% of manufactured feed for Swedish pigs, cattle and chickens was dependent on imported inputs, mainly from Europe, Southeast Asia and South America. Paper III examines ecosystem subsidies to intensive aquaculture in two nations: shrimp production in Thailand and salmon production in Norway. In both countries, aquaculture was shown to rely increasingly on imported subsidies. The rapid expansion of aquaculture turned these countries from fishmeal net exporters to fishmeal net importers, increasingly using inputs from the Southeastern Pacific Ocean.As the examined agricultural and aquacultural production systems became globalized, levels of dependence on other nations’ ecosystems, the number of external supply sources, and the distance to these sources steadily increased. Dependence on other nations is not problematic, as long as we are able to acknowledge these links and sustainably manage resources both at home and abroad. However, ecosystem subsidies are seldom recognized or made explicit in national policy or economic accounts. Economic systems are generally not designed to receive feedbacks when the status of remote ecosystems changes, much less to respond in an ecologically sensitive manner. Papers IV and V discuss the problem of “masking” of the true environmental costs of production for trade. One of our conclusions is that, while the ArEAs approach is a useful tool for illuminating environmentally-based subsidies in the policy arena, it does not reflect all of the costs. Current agricultural and aquacultural production methods have generated substantial increases in production levels, but if policy continues to support the focus on yield and production increases alone, taking the work of ecosystems for granted, vulnerability can result. Thus, a challenge is to develop a set of complementary tools that can be used in economic accounting at national and international scales that address ecosystem support and performance.We conclude that future resilience in food production systems will require more explicit links between consumers and the work of supporting ecosystems, locally and in other regions of the world, and that food security planning will require active management of the capacity of all involved ecosystems to sustain food production.
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| 7. |
- Jonell, Malin, 1983-
(författare)
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Kind of turquoise : Effects of seafood eco-certification and sustainable consumption
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aquaculture and fisheries hold promise for supplying a growing world population with healthy food produced without undermining the earth’s carrying capacity. However, just as livestock production and agriculture, seafood production can have negative environmental impacts and if a continuous or even increased supply is to be guaranteed, the pressure on affected ecosystems needs to be limited. Due in part to a perceived failure of other governance mechanisms in improving the environmental performance of the sector, a large number of voluntary market based standards for farmed and wild caught seafood have been developed. Nonetheless, the knowledge base on the extent to which implementation leads to environmental improvements remains limited. Moreover, the role of consumers in driving demand for eco-labeled seafood is presently an under-researched area. This thesis aims at reducing this knowledge gap through an examination of the potential environmental effectiveness of aquaculture eco-certification and internal, psychological variables predicted to be of importance for sustainable seafood consumption. Put differently, what is the potential of eco-certification in greening the blue revolution and fuel ‘turquoise growth’, and how can consumer demand be spurred?In Paper I, the role of eco-certification in improving the growing aquaculture sector at large was explored. Results showed that environmental effects at global scale likely will be limited due to e.g. partial coverage of species groups and environmental impacts, and a lack of focus on Asian markets and consumers. In Paper II the environmental performance of eco-certified and non-certified mangrove-integrated shrimp farms in Vietnam was compared by using Life Cycle Assessment and put in relation to conventional, more intensive farms. While there was no substantial difference between certified and non-certified farms in terms of environmental impacts, emissions of greenhouse gasses were higher for mangrove-integrated than conventional farms due to mangrove land use change. The results from Paper III demonstrated that the body of literature investigating ecological effects of seafood eco-certification is limited. ‘Spatially explicit ecosystem service information’ (ES-information) on e.g. key ecosystem services and biodiversity in a given area is suggested to have potential to improve sustainability standards. Taking guidance from the pro-environmental behavior literature, consumers in Stockholm, Sweden were consulted on awareness of and attitudes towards eco-labeled seafood (Paper IV-V). Two variables, concern for environmental impacts and knowledge about seafood eco-labels were the best predictors for stated eco-labeled seafood purchasing. Moreover, there seemed to be a misalignment between consumers’ expectations on eco-labeled food in general and certification requirements for eco-labeled seafood.From this set of findings, a number of improvements of current seafood eco-certification are suggested. First, include an LCA-perspective in standards to a higher degree than presently done and provide readily available ES-information in the implementation and evaluation phase of certification. Second, introduce standardized mechanisms for capturing potential environmental improvements over time. And finally, stimulate demand by targeting Asian consumers and markets as well as strengthen consumer eco-label awareness and emotional involvement.
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