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SUSTAIN drilling at Surtsey volcano, Iceland, tracks hydrothermal and microbiological interactions in basalt 50 years after eruption

Tengiliður

Pauline Bergsten

Ph.D. nemi

paulineb@matis.is

The 2017 Surtsey Underwater volcanic System for Thermophiles, Alteration processes and INnovative concretes (SUSTAIN) drilling project at Surtsey volcano, sponsored in part by the International Continental Scientific Drilling Program (ICDP), provides precise observations of the hydrothermal, geochemical, geomagnetic, and microbiological changes that have occurred in basaltic tephra and minor intrusions since explosive and effusive eruptions produced the oceanic island in 1963–1967. Two vertically cored boreholes, to 152 and 192 m below the surface, were drilled using filtered, UV-sterilized seawater circulating fluid to minimize microbial contamination. These cores parallel a 181 m core drilled in 1979. Introductory investigations indicate changes in material properties and whole-rock compositions over the past 38 years. A Surtsey subsurface observatory installed to 181 m in one vertical borehole holds incubation experiments that monitor in situ mineralogical and microbial alteration processes at 25–124 ∘C. A third cored borehole, inclined 55∘ in a 264∘ azimuthal direction to 354 m measured depth, provides further insights into eruption processes, including the presence of a diatreme that extends at least 100 m into the seafloor beneath the Surtur crater. The SUSTAIN project provides the first time-lapse drilling record into a very young oceanic basaltic volcano over a range of temperatures, 25–141 ∘C from 1979 to 2017, and subaerial and submarine hydrothermal fluid compositions. Rigorous procedures undertaken during the drilling operation protected the sensitive environment of the Surtsey Natural Preserve.

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Impact of onboard chitosan treatment of whole cod (Gadus morhua) on the shelf life and spoilage bacteria of loins stored superchilled under different atmospheres

Tengiliður

Pauline Bergsten

Ph.D. nemi

paulineb@matis.is

The initial handling of marine fish on board fishing vessels is crucial to retain freshness and ensure an extended shelf life of the resulting fresh products. Here the effect of onboard chitosan treatment of whole, gutted Atlantic cod (Gadus morhua) was studied by evaluating the quality and shelf life of loins processed six days post-catch and packaged in air or modified atmosphere (% CO2/O2/N2: 55/5/40) and stored superchilled for 11 and 16 days, respectively. Sensory evaluation did not reveal a clear effect of chitosan treatment on sensory characteristics, length of freshness period or shelf life of loins under either packaging conditions throughout the storage period. However, directly after loin processing, microbiological analysis of loins showed that onboard chitosan treatment led to significantly lower total viable counts as well as lower counts of specific spoilage organisms (SSO), such as H2S-producers and Pseudomonas spp., compared to the untreated group. In addition, the culture-independent approach revealed a lower bacterial diversity in the chitosan-treated groups compared to the untreated groups, independently of packaging method. Partial 16S rRNA gene sequences belonging to Photobacterium dominated all sample groups, indicating that this genus was likely the main contributor to the spoilage process.

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New wave of flavours–On new ways of developing and processing seaweed flavours

Seaweeds have a naturally salty taste owing to their high content of minerals like potassium, besides sodium, which can be utilised as a healthy sodium replacer in food. In addition, some seaweeds contain a range of potential flavour components which can be released by mild processing and used to naturally enhance the flavour of food. In the present study, flavour ingredients from brown seaweed to use as a food component were developed. The work included enzymatic processing, by subsequently applying an alginase (Alg3) and Umamizyme to freeze dried and milled Ascophyllum nodosum and Saccharina latissima seaweed biomass. The chemical composition was determined by means of monosaccharide, polyphenol, and sodium content. Flavour profiles of the produced flavour extracts were evaluated by e-tongue and a cell assay, as well as by sensory panellists. The seaweed extracts were incorporated into food models and their sodium replacing and flavour enhancing properties were objectively evaluated by trained sensory panellists. The aim was to offer innovative processing solutions and new healthy flavour ingredients to meet salt reduction targets and flavour enhancing properties using seaweed. The results obtained flavour ingredients that are richer in umami and salty taste with the potential to replace sodium and create flavour enhancing ingredients for certain food products.

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Large differences in carbohydrate degradation and transport potential among lichen fungal symbionts

Lichen symbioses are thought to be stabilized by the transfer of fixed carbon from a photosynthesizing symbiont to a fungus. In other fungal symbioses, carbohydrate subsidies correlate with reductions in plant cell wall-degrading enzymes, but whether this is true of lichen fungal symbionts (LFSs) is unknown. Here, we predict genes encoding carbohydrate-active enzymes (CAZymes) and sugar transporters in 46 genomes from the Lecanoromycetes, the largest extant clade of LFSs. All LFSs possess a robust CAZyme arsenal including enzymes acting on cellulose and hemicellulose, confirmed by experimental assays. However, the number of genes and predicted functions of CAZymes vary widely, with some fungal symbionts possessing arsenals on par with well-known saprotrophic fungi. These results suggest that stable fungal association with a phototroph does not in itself result in fungal CAZyme loss, and lends support to long-standing hypotheses that some lichens may augment fixed CO2 with carbon from external sources.

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Going to extremes–a metagenomic journey into the dark matter of life

The Virus-X—Viral Metagenomics for Innovation Value—project was a scientific expedition to explore and exploit uncharted territory of genetic diversity in extreme natural environments such as geothermal hot springs and deep-sea ocean ecosystems. Specifically, the project was set to analyse and exploit viral metagenomes with the ultimate goal of developing new gene products with high innovation value for applications in biotechnology, pharmaceutical, medical, and the life science sectors. Viral gene pool analysis is also essential to obtain fundamental insight into ecosystem dynamics and to investigate how viruses influence the evolution of microbes and multicellular organisms. The Virus-X Consortium, established in 2016, included experts from eight European countries. The unique approach based on high throughput bioinformatics technologies combined with structural and functional studies resulted in the development of a biodiscovery pipeline of significant capacity and scale. The activities within the Virus-X consortium cover the entire range from bioprospecting and methods development in bioinformatics to protein production and characterisation, with the final goal of translating our results into new products for the bioeconomy. The significant impact the consortium made in all of these areas was possible due to the successful cooperation between expert teams that worked together to solve a complex scientific problem using state-of-the-art technologies as well as developing novel tools to explore the virosphere, widely considered as the last great frontier of life.

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A fast and inexpensive high-throughput protocol for isolating high molecular weight genomic DNA from lichens

Werth, S., Reynisdóttir, S., Guðmundsson, H. & Andrésson, Ó. S. 2016. A fast and inexpensive high-throughput protocol for isolating high molecular weight genomic DNA from lichens. — Herzogia 29: 610–616. Isolating high molecular weight DNA as required for genomic library preparations and other applications is a challenging task. We optimized a glass-fiber column-based, high throughput DNA isolation protocol to yield comparatively large quantities of high molecular weight, pure DNA; cell lysis based on a CTAB buffer was followed by centrifugation to remove cell debris, binding to a glass-fiber membrane under high concentration of a chaotropic salt (guanidine hydrochloride), followed by two 70 % ethanol washes and elution. This method was utilized successfully on several species of lichenized ascomycetes and on two non-lichenized basidiomycetes. Thus, while developed for lichens, the method is suitable for a range of fungal taxa.

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Interactive governance of whale ecosystem services: governability assessment of three case studies in the Arctic

The social-ecological change in the Arctic is accelerated by the multifaceted effects of climate change and globalization. Among other things, this means changing human-ecosystem dynamics through altered availability, co-production, and governance of ecosystem services (ES). A group of species illustrative of this change are whales, migratory species that have played an important part in the culture and subsistence of Arctic communities for millennia. This study explores the changing human-nature interactions and whale ES governance by combining ES and interactive governance theories. A multi-method approach is applied to assess qualitatively the qualitative governability of whale ES in three Arctic coastal locations: Húsavík in Iceland, Andenes in Norway, and Disko Bay in Greenland. Based on a literature review, stakeholder mapping, observations, and analysis of 54 semi-structured stakeholder interviews, the study finds that whale ES governance involves multiple actors with differing preferences and values and that much of it happens outside of formal institutions, necessitating inclusive approaches to improve it. The study reveals some whale ES governance deficiencies and potentials, such as a mismatch between governance scales and a need for more formal governance practices based on scientific research and stakeholder inputs. Governance frameworks were present for provisioning whale ES related to whaling, but they were lacking for non-consumptive whale ES, such as whale watching. Addressing these issues can help to direct marine resource management toward sustainability by making it more inclusive, adaptive, and reflective of stakeholder needs and values. This goal could be advanced by applying the governance principles that view humans as an integral part of social-ecological systems, e.g., ecosystem stewardship and ecosystem-based management.

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Socio-cultural valuation of whale ecosystem services in Skjálfandi Bay, Iceland

The study examines the socio-cultural values of multiple ecosystem services (ES) sourced from whales in Skjálfandi Bay, North Iceland, with many beneficiaries living in and visiting the town of Húsavík. The study begins to address the research gap in non-monetary valuation of marine ecosystem services. Based on a multi-method approach, it elicits stakeholders’ perceptions of the contribution of whale ES to human wellbeing using stakeholder mapping, semi-structured interviews, observations, and socio-cultural preference surveys. The key whale ES identified by the local stakeholders were cultural, most frequently mentioned being recreation and education. The most commonly mentioned ES values were related to economic benefits from the whale watching industry. The preference survey reveals that regulating and maintenance ES were valued most highly with a mean score of 4.0 out of 5.0, cultural ES were second with a mean score of 3.5, and provisioning ES in the form of food and raw materials were valued the least with a mean of 0.75. Interview data also reveals some marine ES management challenges originating from intensified tourism, industrial development, and climate change. The results of the study have the potential to inform marine resource management in Iceland by including socio-cultural values associated with whale resources.

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Whale Ecosystem Services and Co-production Processes Underpinning Human Wellbeing in the Arctic: Case Studies from Greenland, Iceland and Norway

The concept of ecosystem services (ES) has only just begun to be applied in the Arctic, and to an even lesser extent to marine mammals, such as whales. This chapter develops an ES cascade model and related ES co-production processes as they apply to whale resources in the Arctic. The result is a new conceptual model demonstrating the interconnectedness of social-ecological processes involving natural and human capital that enhance human wellbeing through the co-creation of whale ES. An ES cascade model is presented for whale ES, which connects the five linked stages of such ES production: the biophysical structure, functions, ecosystem services, the benefits to human wellbeing, and associated values. They are further expanded to include the co-production processes of whale ES as well as its main stages, inputs, and flows. These processes are illustrated using examples from ARCPATH case studies of coastal communities dependent on whale resources: Húsavík in Iceland, Andenes in Norway, and Ilulissat/Disko Bay in Greenland. The chapter aims to improve the understanding of the human dimensions of ES and the underlying processes that enable Arctic coastal communities to benefit from whales. It provides a starting point for further analysis of possible research and management approaches regarding whale resources in the Arctic.

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Willingness to pay for expansion of the whale sanctuary in Faxaflói Bay, Iceland: A contingent valuation study

Commercial whaling is a divisive issue in Iceland, and often considered to be irreconcilable with whale watching. The coexistence of both activities in Faxaflói Bay, adjacent to the capital city of Reykjavík, has led to the designation of part of the bay as a whale sanctuary, where whaling is banned. The study utilises the contingent valuation method to elicit the preferences of Icelanders and estimate their willingness to pay (WTP) to expand the sanctuary to the full extent of Faxaflói Bay, with an aim to inform marine spatial planning in Iceland. Using the double-bounded dichotomous approach, the mean WTP for expansion of the Faxaflói Bay Whale Sanctuary was estimated to be 5082 ISK/42 USD per person (1.32 billion ISK/10.9 million USD when multiplied by the number of taxpayers), and 29.7% of the respondents with clearly defined preferences expressed positive WTP. According to the logit regression model, statistically significant socioeconomic and attitudinal variables included age, gender, level of education, number of persons in a household, and attitudes towards environmental conservation and whaling. Policy implications of non-market valuation of marine ES are discussed, pointing to a need to further assess the multiple marine ES values applying a transdisciplinary approach to inform decision-making.

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