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Guidelines for co-creating climate adaptation plans for fisheries and aquaculture

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Ragnhildur Friðriksdóttir

Project Manager

ragnhildur@matis.is

Climate change is having a significant impact on the biology and ecology of fish stocks and aquaculture species and will affect the productivity within seafood supply chains in the future. The challenges are further amplified when actors within the fisheries and aquaculture sectors have very different ideas and assumptions about climate change and what risks and opportunities they entail. In order to address the challenges of climate change, several countries have developed national adaptation plans. However, fisheries and aquaculture are rarely included in these plans, resulting in a general lack of documented adaptation strategies within these sectors in most countries. This paper introduces guidelines for the development of climate adaptation plans (CAPs) within fisheries and aquaculture, applying a co-creation approach that requires the participation of scientists, industry representatives, policymakers, and other relevant stakeholders. The objective is to provide a stepwise approach to facilitate and enable stakeholders to plan strategies toward climate adaptation. The guidelines are based on practical experience and include a three-step process: (1) assessment of risks and opportunities; (2) identification of adaptation measures, and (3) operationalization of CAPs. The three-step process is also part of a larger cycle, including implementation, monitoring, and evaluation, again generating iterative feedback loops over time. Lessons learned are discussed, and we highlight the advantages and challenges of developing CAPs. While the guidelines are designed for and tested within fisheries and aquaculture systems, the CAP approach is also employable for other natural resource-based systems.

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Effect of Dietary Seaweed Supplementation in Cows on Milk Macrominerals, Trace Elements and Heavy Metal Concentrations

This study investigated the effect of seaweed supplementation in dairy cow diets on milk yield, basic composition, and mineral concentrations. Thirty-seven Icelandic cows were split into three diet treatments: control (CON, no seaweed), low seaweed (LSW, 0.75% concentrate dry matter (DM), 13–40 g/cow/day), and high seaweed (HSW, 1.5% concentrate DM, 26–158 g/cow/day). Cows were fed the same basal diet of grass silage and concentrate for a week, and then were introduced to the assigned experimental diets for 6 weeks. The seaweed mix of 91% Ascophyllum nodosum: 9% Laminaria digitata (DM basis), feed, and milk samples were collected weekly. Data were analyzed using a linear mixed effects model, with diet, week, and their interaction as fixed factors, cow ID as random factor, and the pre-treatment week data as a covariate. When compared with CON milk, LSW and HSW milk had, respectively, less Se (−1.4 and −3.1 μg/kg milk) and more I (+744 and +1649 μg/kg milk), while HSW milk also had less Cu (−11.6 μg/kg milk) and more As (+0.17 μg/kg milk) than CON milk. The minimal changes or concentrations in milk for Se, Cu, and As cannot be associated with any effects on consumer nutrition, but care should be taken when I-rich seaweed is fed to cows to avoid excessive animal I supply and milk I concentrations.

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Functional and nutraceutical ingredients from marine macroalgae. In: Handbook of Seafood Quality, Safety and Health Applications

The global market for seafood products continues to increase year by year. Food safety considerations are as crucial as ever in this sector, and higher standards of quality are demanded even as products are shipped greater distances around the world. The current global focus on the connection between diet and health drives growth in the industry and offers commercial opportunities on a number of fronts. There is great interest in the beneficial effects of marine functional compounds such as omega-3 polyunsaturated fatty acids. Seafoods are well-known as low calorie foods, and research continues into the nutritional effects on, for example, obesity and heart disease. In addition, by-products of marine food processing can be used in nutraceutical applications.

This book is a resource for those interested in the latest advances in the science and technology of seafood quality and safety as well as new developments in the nutritional effects and applications of marine foods. It includes chapters on the practical evaluation of seafood quality; novel approaches in preservation techniques; flavour chemistry and analysis; textural quality and measurement; packaging; the control of food-borne pathogens and seafood toxins. New research on the health-related aspects of marine food intake are covered, as well as the use of seafoods as sources of bioactives and nutraceuticals. The book is directed at scientists and technologists in academia, government laboratories and the seafood industries, including quality managers, processors and sensory scientists.

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Automated and large-scale characterization of microbial communities in food production. In: Rapid detection, characterization, an enumeration of foodborne pathogens

Microbial communities in food and food production establishments have highly versatile structures based on various extrinsic factors. The information gained by large-scale microbial community analysis not only can deepen the understanding of food microbiology in general but also can lead to improvement of food production systems for increased quality and safety and extension of shelf life. This chapter reviews the most recent methods applied to microbial communities, and presents examples of some cutting-edge technologies. Molecular methods have been developing rapidly in recent years both for specific detection of single species and for screening assays that allow the species composition of a given food sample to be unraveled. Examples of those methods are 16S rRNA clone analysis, fingerprinting methods such as terminal restriction fragment length polymorphism (t-RFLP) and denaturing gradient gel electrophoresis (DGGE), tag-encoded pyrosequencing, single-nucleotide primer extension (SNuPE), and microarrays. Furthermore, flow cytometry is also addressed in the chapter, but this technique is based on single-cell analysis whereby a cell suspension is concentrated by nanofluidics and analyzed by laser technology. High-throughput analysis of microbial populations in food products and food processing environments has revealed the existence of a higher complexity in the microbial world than previously expected. The new approaches provide opportunities for further understanding of the microbial developments that are initiated during food production and storage.

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Microbial speciation in the geothermal ecosystem. In: Adaption of microbial life to environmental extremes: Novel Research Results and Application

Once considered exceptional rarities, extremophiles have become attractive objects for basic and applied research ranging from nanotechnology to biodiversity to the origins of life and even to the search for extraterrestrial life. Several novel aspects of extremophiles are covered in this book; the focus is firstly on unusual and less explored ecosystems such as marine hypersaline deeps, extreme cold, desert sands, and man-made clean rooms for spacecraft assembly. Secondly, the increasingly complex field of applications from extremophile research is treated and examples such as novel psychrophilic enzymes, compounds from halophiles, and detection strategies for potential extraterrestrial life forms are presented.

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Are Mercury Levels in Arctic Biota Increasing or Decreasing, and Why? In: AMAP Assessment 2011: Mercury in the Arctic

An analysis of the temporal trends for mercury in Arctic biota is
important for scientists and managers concerned with making
sound science-based policy with respect to changes in Hg in
the Arctic environment. Long-term datasets (i.e., comparing
modern with historical or pre-industrial Hg concentrations)
can be used to estimate the relative importance of natural and
anthropogenic Hg inputs in modern biota and the environment,
while short-term datasets (i.e., covering the past one to three
decades) illustrate how Hg concentrations have changed in
recent times and suggest likely trends in the near-term future.
In the previous AMAP assessment of Hg in the Arctic
environment (AMAP, 2005), evidence of increasing Hg
concentrations from pre-industrial or historical to more
recent times was presented for Arctic marine biota. Those
trends were shown to continue in recent (short-term) datasets,
primarily in higher-order marine biota from Canada and West
Greenland. In contrast, time series for lower-order marine biota
for Iceland and the European Arctic showed a general pattern
of recently stable or declining Hg concentrations. The reasons
for this spatial difference in trend patterns were not clear.
Data for higher-order marine biota from Europe and Iceland
were lacking as were temporal trend datasets for biota from
Russia and Finland. One of the recommendations resulting
from the previous AMAP assessment was that temporal trend
monitoring of Hg concentrations should be continued in order
to obtain longer and more statistically reliable trend analyses.
This chapter presents an update of the information available
for both long-term and short-term trends, including a statistical
meta-analysis of recent temporal trends in Hg concentrations
in Arctic biota. The final section presents a discussion, using
case studies, of the possible mechanisms driving the temporal
trends observed.

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Effects of different pre-salting methods on protein aggregation during heavy salting of cod fillets

The use of injection and brining as the first step in heavy salting of cod increases weight yields of the products through both salting and rehydration, compared to other pre-salting methods, like brining only and pickling. This is interesting since salt content of the muscle exceeds 20% NaCl, in all procedures. Therefore, the dissimilarities in yield were presumed to depend on the degree of protein denaturation and aggregation as influenced by the different salting procedures. This hypothesis was studied and confirmed with the aid of SDS–PAGE and DSC-analysis. Higher water retention of injected products was explained by stronger salting-in effects on proteins during pre-salting, reducing aggregation of muscle proteins during the dry salting step. The degree of protein aggregation during salting increased in the following order with regard to the different pre-salting methods: injection and brining < brining < pickling. These effects were still observed after rehydration. Furthermore, differences in denaturation/aggregation were assigned to both myosin and collagen.

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The effects of salt concentration on conformational changes in cod (Gadus morhua) proteins during brine salting

The effects of different salt concentrations (6%, 15%, 18% and 24% NaCl (w/w)) on the conformational changes of cod muscle proteins during brine salting were examined in this study. Proteins were extracted from the brine salted samples with solutions of 1 M (5.9%) and 4 M (23.4%) NaCl and the quantity of salt soluble proteins (SSP), disulfide bond (S–S), total sulfhydryl (SH) and available SH content in the soluble fraction were determined. Increased salt concentration in cod muscle promoted protein denaturation and aggregation. The SSP and total SH content decreased, whereas the S–S bond and available SH content increased with increased salt concentration in cod muscle. Disulfide bond formation correlated (r = −0.6) with a decrease in total SH groups. Higher SSP and available SH groups of the samples at lower brine concentrations was explained by smaller concentration gradients and salt diffusion rates, resulting in stronger salting-in at early stages of the brining process. There was a significant difference in conformational changes in proteins extracted with a salt solution of 1 and 4 M, mainly due to a different degree of protein aggregation.

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The effects of salt-curing and salting procedures on the microstructure of cod (Gadus morhua) muscle

The aim of this study was to investigate the effects of salting and different pre-salting procedures (injection and brining versus brining only) on the microstructure and water retention of heavy salted cod products. Salting resulted in shrinkage of fibre diameter and enlargement of inter-cellular space. Water was expelled from the muscle and a higher fraction became located in the extra-cellular matrix. These changes were suggested to originate from myofibrillar protein aggregation and enzymatic degradation of the connective tissue. During rehydration, the muscle absorbed water again and the fibers swelled up to a similar cross-sectional area as in the raw muscle. However, the inter-cellular space remained larger, resulting in a higher water content of the muscle in the rehydrated stage. The effects of different salting procedures were strongest after salting. At that stage of the process, the inter-cellular space tended to be larger in the injected and brined muscle than in the brined only.

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A pilot genetic study reveals the absence of spatial genetic structure in Norway lobster (Nephrops norvegicus) on fishing grounds in Icelandic waters

Stock structure of Norway lobster off southern Iceland was investigated using 12 microsatellite loci. No genetic method detected significant genetic differentiation among the locations sampled, even among Icelandic samples and an out-group from Scotland. Testing the power of resolution of microsatellite loci, the loci and sample sizes used were sufficient to detect significant genetic differentiation with confidence. The lack of genetic structure is discussed in terms of the level of gene flow, recent isolation of populations, and the statistical power of the experimental design.

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