Northeast Iceland Research Articles

Tooth wear with an erosive component in a Mediaeval Iceland population

ObjectivesDental erosion is generally thought of as a modern phenomenon, but there is emerging evidence that the condition has always been present in the human dentition to some degree. The aim of this study was to quantitatively evaluate the severity of tooth wear observed in skeletal material from a mediaeval population of the farm at Hofstaðir, Mývatnssveit, in northeast Iceland. MethodsThe teeth were examined and tooth wear was quantified using the Smith and Knight Tooth Wear Index. All surfaces of the teeth were examined by a single trained examiner from 53 adult skulls available (24 males and 29 female). The majority of the skulls were examined at the stores of Þjóðminjasafn Íslands (The National Museum of Iceland) using good lighting and magnification. ResultsThere were a total of 1696 possible teeth and 6784 surfaces, and from this 69.5% were scored. There was a higher overall rate of wear in the mandibular dentitions and that the highest wear rates were seen on the occlusal/incisal surfaces of the 1st and 2nd molars and the premolars. For the group, and from those surfaces available for scoring, dentine was exposed on 1464 surfaces (31%). There was no evidence of cervical wear. ConclusionHigh levels of tooth wear were observed in this Icelandic assemblage and the appearance was characteristic of both chemical and physical wear.

Application of 34S analysis for elucidating terrestrial, marine and freshwater ecosystems: Evidence of animal movement/husbandry practices in an early Viking community around Lake Mývatn, Iceland

Carbon and nitrogen stable isotope ratios (δ13C and δ15N) have been used widely in archaeology to investigate palaeodiet. Sulphur stable isotope ratios (δ34S) have shown great promise in this regard but the potential of this technique within archaeological science has yet to be fully explored. Here we report δ34S, δ13C and δ15N values for 129 samples of animal bone collagen from Skútustaðir, an early Viking age (landnám) settlement in north-east Iceland. This dataset represents the most comprehensive study to date of its kind on archaeological material and the results show a clear offset in δ34S values between animals deriving their dietary resources from terrestrial (mean=+5.6±2.8‰), freshwater (mean=−2.7±1.4‰) or marine (mean=+15.9±1.5‰) reservoirs (with the three food groups being significantly different at 2σ). This offset allows reconstruction of the dietary history of domesticated herbivores and demonstrates differences in husbandry practices and animal movement/trade, which would be otherwise impossible using only δ13C and δ15N values. For example, several terrestrial herbivores displayed enriched bone collagen δ34S values compared to the geology of the Lake Mývatn region, indicating they may have been affected by sea-spray whilst being pastured closer to the coast, before being traded inland. Additionally, the combination of heavy δ15N values coupled with light δ34S values within pig bone collagen suggests that these omnivores were consuming freshwater fish as a significant portion of their diet. Arctic foxes were also found to be consuming large quantities of freshwater resources and radiocarbon dating of both the pigs and foxes confirmed previous studies showing that a large freshwater radiocarbon (14C) reservoir effect exists within the lake. Overall, these stable isotope and 14C data have important implications for obtaining a fuller reconstruction of the diets of the early Viking settlers in Iceland, and may allow a clearer identification of the marine and/or freshwater 14C reservoir effects that are known to exist in human bone collagen.

Modelling of temperature conditions near the bottom of well IDDP-1 in Krafla, Northeast Iceland

The transient temperature conditions near the bottom of well IDDP-1 in Krafla, which was drilled into a magma intrusion, have been simulated by some simple models of: (i) evolution of temperature conditions at the magma intrusion, (ii) cooling of the producing zone, a permeable layer above the intrusion, due to circulation losses during drilling and subsequent injection, (iii) reheating of the permeable layer after drilling and (iv) temperature evolution during the early phases of discharge testing in 2010. The modelling is not definitive, and does not consider later, more long-term flow testing (2011–2012), because the necessary down-hole data are lacking. However, results indicate that the evolution of the temperature conditions can be explained by these models. If the magma was emplaced during the most recent Krafla volcanic episode 25–35 years ago, the intrusion must have a thickness of at least 50–100m. The effective thickness of the permeable layer is estimated to be about 45m and its equilibrium temperature to be 390–400°C. No direct contact of the fluid with the magma is needed to explain the superheated steam discharged by the well. The situation near the bottom of the well clearly warrants further study, both through more advanced modelling and input of further data. The IDDP-1 well had to be quenched in July 2012. Whether it can maintain in the long-term the high energy output (15–40MWe), achieved during discharge testing, depends on sufficient recharge and efficient heat-exchange, if it can be rehabilitated. Carefully executed reinjection may be the solution if long-term recharge is not sufficient.

Long-term frequency and characteristics of dust storm events in Northeast Iceland (1949–2011)

Long-term records of meteorological dust observations from Northeast Iceland were analysed and frequency of dust events from Icelandic deserts calculated. A total of 1033 dust days were reported during the period 1949–2011 with an annual mean of 16.4 dust days year−1, placing the area among the dustiest areas in the world. The most active decades were the 2000s, 1990s and 1950s. Monthly dust event frequency is bimodal with primary and secondary maxima in June and September. A total of 14 severe dust storms (visibility < 500 m) occurred during the period. Median dust event concentration was calculated as 106 μg m−3 from the visibility observations. The frequency and severity of dust events depend on Sea Level Pressure (SLP) oscillation which controls the southerly winds in NE Iceland. The availability of fine sediments susceptible to dust production in outwash plains controlled by the flow rate of glacial river is also important. Volcanic ash from eruptions in 2010 and 2011 barely affected the dust event frequency in NE Iceland. Icelandic dust may be substantial source for large scale air pollution in the Arctic.

Dating of the Viking Age Landnám Tephra Sequence in Lake Mývatn Sediment, North Iceland

Abstract Soil profiles and archaeological sites in Northeast Iceland contain a sequence of basaltic tephra layers coinciding in time with the first human settlement of the area during the Viking Age, known as the Landnam tephra sequence. The chronology of these layers is useful when reconstructing the history of human settlement in Iceland and its environmental impact. The only properly dated tephra layer from this tephra sequence is the Landnam tephra layer (LTL), formed in the A.D. 870s. Sedimentation rates calculated from the interval between tephra layers of known age (A.D. 871 ± 2, 1158, and 1300) in high-resolution sediment cores from Lake Mývatn were used to establish the approximate age of six tephra layers in the medieval period. One of the main objectives of the study was to improve dating of a younger tephra layer, formed in the mid-10th century according to previous studies. This tephra layer, originating from the Veiðivotn volcanic system, has proven to be a very important marker bed for arch...

Influence of increased cod abundance and temperature on recruitment of northern shrimp (Pandalus borealis)

Despite an increase in northern shrimp (Pandalus borealis) female biomass in the past years, the recruitment of the offshore population north and northeast of Iceland has remained very low. In this study, the influence of abiotic and biotic factors was studied in relation to shrimp recruitment. Two factors, cod (Gadus morhua) abundance and summer sea surface temperature (SST), were found to have a negative effect on offshore shrimp recruitment, explaining 71 % of the observed variation. Both cod abundance and temperature on the offshore shrimp grounds have increased in the past years, while recruitment has decreased and been at historically low levels since 2005. No significant relationship was found between recruitment and spawning biomass, indicating that recruitment variability is mainly driven by other factors. Cod abundance and summer SST are likely to affect different life stages of shrimp, as SST influences shrimp during its planktonic phase while cod abundance influences the demersal stage.

Connectivity in a pond system influences migration and genetic structure in threespine stickleback.

Neutral genetic structure of natural populations is primarily influenced by migration (the movement of individuals and, subsequently, their genes) and drift (the statistical chance of losing genetic diversity over time). Migration between populations is influenced by several factors, including individual behavior, physical barriers, and environmental heterogeneity among populations. However, drift is expected to be stronger in populations with low immigration rate and small effective population size. With the technological advancement in geological information systems and spatial analysis tools, landscape genetics now allows the development of realistic migration models and increased insight to important processes influencing diversity of natural populations. In this study, we investigated the relationship between landscape connectivity and genetic distance of threespine stickleback (Gasterosteus aculeatus) inhabiting a pond complex in Belgjarskógur, Northeast Iceland. We used two landscape genetic approaches (i.e., least-cost-path and isolation-by-resistance) and asked whether gene flow, as measured by genetic distance, was more strongly associated with Euclidean distance (isolation-by-distance) or with landscape connectivity provided by areas prone to flooding (as indicated by Carex sp. cover)? We found substantial genetic structure across the study area, with pairwise genetic distances among populations (DPS) ranging from 0.118 to 0.488. Genetic distances among populations were more strongly correlated with least-cost-path and isolation-by-resistance than with Euclidean distance, whereas the relative contribution of isolation-by-resistance and Euclidian distance could not be disentangled. These results indicate that migration among stickleback populations occurs via periodically flooded areas. Overall, this study highlights the importance of transient landscape elements influencing migration and genetic structure of populations at small spatial scales.

History of Gas in Geothermal Fluids, Krafla, Northeast Iceland

From 1871 to 1975 there was little change in the gas composition of Krafla fluids. Parts of the system were affected by magmatic gas during the Krafla fires of 1975-1984. In some parts the gas composition has gradually come back to the pre-1975 levels, but gas concentrations have risen elsewhere, apparently due to heating in parts that were not directly affected by volcanic gas.

The impact of past climate change on genetic variation and population connectivity in the Icelandic arctic fox

Previous studies have suggested that the presence of sea ice is an important factor in facilitating migration and determining the degree of genetic isolation among contemporary arctic fox populations. Because the extent of sea ice is dependent upon global temperatures, periods of significant cooling would have had a major impact on fox population connectivity and genetic variation. We tested this hypothesis by extracting and sequencing mitochondrial control region sequences from 17 arctic foxes excavated from two late-ninth-century to twelfth-century AD archaeological sites in northeast Iceland, both of which predate the Little Ice Age (approx. sixteenth to nineteenth century). Despite the fact that five haplotypes have been observed in modern Icelandic foxes, a single haplotype was shared among all of the ancient individuals. Results from simulations within an approximate Bayesian computation framework suggest that the rapid increase in Icelandic arctic fox haplotype diversity can only be explained by sea-ice-mediated fox immigration facilitated by the Little Ice Age.

Mobile Communities: The Gathering and Sorting of Sheep in Skútustaðarhreppur, Northeast Iceland

This paper concerns the mobilities associated with the gathering and sorting of sheep within the community of Skutustarðarhreppur, northeast Iceland in the recent historic period. It examines the relationships between people, animals, and landscape in terms of their movements. It presents an argument based on examining the mobilities on the surface and in the depths of a continual, in-the-making landscape, and considers the dwelling of farmers and their movements in attending to sheep as both place-forming and identity-forming processes. I present a hypothetical gathering and sorting of sheep based on historical and archaeological sources and explore the relations that are formed on-the-move.

The composition of adult overwintering and juvenile aggregations of Atlantic cod (Gadus morhua) around Iceland using neutral and functional markers: a statistical challenge

The collapse of marine fisheries worldwide has forced recognition of the fact that sustainable fisheries management cannot be achieved without a reasonable understanding of stock structure. Fisheries focusing on species that exhibit seasonal migrations between spawning and feeding grounds should consider the composition of feeding aggregations of presumed mixed origin. Using nine microsatellites and the Pan I locus, we assess the contribution of two previously described major spawning components of Icelandic cod Gadus morhua (southwest and northeast) to two large feeding and two large juvenile aggregations of presumed mixed origin and situated in the northwest and northeast of Iceland. The Bayesian approaches (STRUCTURE and BAYES) revealed that, with the exception of the juvenile samples collected in 2002 and 2003 in the northeast, most of the individuals originated from the southwest. These results confirmed that the Icelandic cod exhibit a complex biological pattern involving spawning site fidelity and migration to and from feeding aggregations. The sustainable management of the Icelandic cod is likely to be compromised if its complex dynamics is not properly integrated into fisheries management plans.

Floor formation processes and the interpretation of site activity areas: An ethnoarchaeological study of turf buildings at Thverá, northeast Iceland

The importance of identifying activity areas on archaeological sites has focussed much ethnoarchaeological and geoarchaeological research on floor formation processes, especially the cultural practices and preservation conditions affecting the distributions of artefacts, organic residues, and elements. In order to broaden the understanding of site formation processes in northern regions, an ethnoarchaeological study integrating geoarchaeological methods was conducted at abandoned 19th- and early 20th-century turf buildings at the farm of Thverá, northeast Iceland. Micromorphological analysis of the floor deposits in different rooms, compared to the former resident’s descriptions of how space had been used and how floors had been maintained, revealed that only a few activities resulted in the accumulation of residues that were diagnostic of how space had been used on a daily basis. Instead, floor layers were dominated by residues associated with maintenance events, such as the intentional spreading of ash, and the laying of fresh turf. This study highlighted the fact that “dirty”, “clean”, “comfortable”, and “waste”, are socially constructed concepts that have a significant impact on the composition of occupation surfaces and must be given careful consideration by archaeologists attempting to spatially analyse residues in floor deposits to interpret site activity areas.

The Parasite Fauna of Rock Ptarmigan (Lagopus muta) in Iceland: Prevalence, Intensity, and Distribution Within the Host Population

One hundred rock ptarmigan (Lagopus muta), including 30 each of juvenile males and females, and 20 each of adult males and females, were collected in October 2006 in northeast Iceland to study their parasite fauna. Fourteen different parasite species were identified: 6 endoparasites (including the protozoans Eimeria muta, Eimeria rjupa; the heterokontophyt Blastocystis sp.; the nematodes Capillaria caudinflata and Trichostrongylus tenuis; and the cestode Passerilepis serpentulus) and 8 ectoparasites (including the feather mites Metamicrolichus islandicus, Strelkoviacarus holoaspis, Tetraolichus lagopi, and Myialges borealis; the feather lice Goniodes lagopi, Lagopoecus affinis, and Amyrsidea lagopi; and the louse fly Ornithomya chloropus). Blastocystis sp., P. serpentulus and A. lagopi are new host records. All parasite species showed aggregated distributions. Six species, E. rjupa, P. serpentulus, M. islandicus, G. lagopi, L. affinis, and O. chloropus, were more prevalent in juveniles than in adults, and 2 species, Blastocystis sp. and T. tenuis, were more prevalent in adults than in juveniles. The remaining species did not show age-related differences in prevalence. Blastocystis sp. is the only possible zoonotic parasite.

Gendered Outcomes of Socio-economic Restructuring: A Tale from a Rural Village in Iceland

Demographic dynamics are immanent in societal changes. However, recent research on work-related mobility and regional development indicate that translocal commodity chains have changed the formation of class and gender to such an extent that spatial constructions of belonging have not only become more complex in local communities but are also, to an increased extent, the main deciding factor in women's reflective decision-making processes on where to live. This article explores the reasoning behind women's choices about how to live and work, across functional occupations, age, and educational background, in a small peripheral village in north-east Iceland. The community aspect is crucial in this respect. How do they perceive their own function and embeddedness in the community? The findings indicate that the key reason for staying and living in a community with few occupational opportunities is the existence of family and social ties, although jobs suited to their educational backgrounds and economic needs are also of crucial importance.

Developing Wellness in Iceland. Theming Wellness Destinations the Nordic Way

This paper deals with the development of Iceland as a wellness destination with specific focus on a development project in the north‐east (NE) of the country. Iceland is known as a destination for nature‐based tourism with the vast majority of people visiting the country for the wilderness or natural elements. Complementing the nature‐based tourism on offer, especially in the uninhabited highland interior, has been the occasional dip into a natural geo‐thermal pool, often to be found in unique settings and of a great variety when it comes to water qualities. Since the 1970s, Icelanders have been very actively using these geo‐thermal waters for the build up of heating utilities in the country, in swimming pools and for producing electricity. The most famed tourism consequence of these developments is undoubtedly the Blue Lagoon. In the NE of Iceland a similar service facility has been built but under wholly different terms. This paper demonstrates a lack of a vision in the development of Iceland as a wellness destination on the entrepreneurial level. Moreover, in terms of the case outlined, these entrepreneurs find little commonalities with a specific Nordic wellbeing concept and have a much more internationally‐oriented comparative outlook.

Separated determination of the velocity structure and earthquake hypocenter parameters on the basis of the differentiated approach

The problem of seismic tomography, in its linearized statement, is characterized by models consisting of many parameters for velocity structures and hypocenters. The standard approach solves this problem by simultaneously finding both seismic parameters. In the present communication, we present evidence that the velocity structure can be determined at fixed values of the earthquake hypocenter parameters. Instead of the standard approach, we use differential one, which allows us to built inversion solutions stable in relation to significant noise, including errors in the hypocenter parameters as well. We conclude that the greater the number of hypocenters involved in inversion, the better the tomography result. This conclusion is proved by testing the Tjornes fault zone in the northeast of Iceland.

Growth and Energy Budget Models of the BivalveArctica islandicaat Six Different Sites in the Northeast Atlantic Realm

We compared lifetime and population energy budgets of the extraordinary long-lived ocean quahog Arctica islandica from 6 different sites—the Norwegian coast, Kattegat, Kiel Bay, White Sea, German Bight, and off northeast Iceland—covering a temperature and salinity gradient of 4-10C (annual mean) and 25-34, respectively. Based on von Bertalanffy growth models and size-mass relationships, we computed organic matter production of body (PSB) and of shell (PSS), whereas gonad production (PG) was estimated from the seasonal cycle in mass. Respiration (R) was computed by a model driven by body mass, temperature, and site. A. islandica populations differed distinctly in maximum life span (40 y in Kiel Bay to 197 y in Iceland), but less in growth performance (f# ranged from 2.41 in the White Sea to 2.65 in Kattegat). Individual lifetime energy throughput, as approximated by assimilation, was highest in Iceland (43,730 kJ) and lowest in the White Sea (313 kJ). Net growth efficiency ranged between 0.251 and 0.348, whereas lifetime energy investment distinctly shifted from somatic to gonad production with increasing life span; PS/PG decreased from 0.362 (Kiel Bay, 40 y) to 0.031 (Iceland, 197 y). Population annual energy budgets were derived from individual budgets and estimates of population mortality rate (0.035/y in Iceland to 0.173/y in Kiel Bay). Relationships between budget ratios were similar on the population level, albeit with more emphasis on somatic production; PS/ PG ranged from 0.196 (Iceland) to 2.728 (White Sea), and P/B ranged from 0.203-0.285/y. Life span is the principal determinant of the relationship between budget parameters, whereas temperature affects net growth efficiency only. In the White Sea population, both growth performance and net growth efficiency of A. islandica were lowest. We presume that low temperature combined with low salinity represent a particularly stressful environment for this species.

Investigation of Li/Ca variations in aragonitic shells of the ocean quahog Arctica islandica, northeast Iceland

Interannual and intra‐annual variations in lithium‐to‐calcium ratio were investigated with high temporal resolution in the aragonitic outer shell layer of juvenile Arctica islandica (Mollusca; Bivalvia) collected alive in 2006 off northeast Iceland. Li/Cashell ranged between 7.00 and 11.12 μmol mol−1 and presented well‐marked seasonal cycles with minimum values recorded at the annual growth lines; a general pattern was a progressive increase in Li/Cashell from March to May, followed by a plateau in June and a decrease down to minimum values in July–August. Li/Cashell was correlated with δ18Oshell‐derived temperature, but the strength of this relationship was weak (r2 &lt; 0.25 and p &lt; 0.05). It covaried significantly with microgrowth increment width and with the discharge from one of the closest rivers. Seasonal variations of Li/Cashell in A. islandica may most likely be explained (1) by calcification rate and/or (2) by significant river inputs of Li‐rich silicate particles flowing to the sea as soon as snow melts. In the first case, Li/Cashell may be a useful proxy for addressing seasonal variations of growth rate in bivalves that lack discernable microgrowth patterns. Abrupt decreases of Li/Cashell may, in turn, help identify growth retardations due to harsh environmental conditions. Alternatively, if Li/Cashell variations are linked to particulate Li inputs by rivers, this could be a new proxy for the intensity of mechanical weathering of Icelandic basalts, with interesting perspectives for the reconstruction of frequency and intensity of past jökulhlaups (subglacial outburst floods). Further works, including experimental studies, are needed to test these hypotheses.

From good to eat to good to watch: whale watching, adaptation and change in Icelandic fishing communities

Arctic and North Atlantic fishing communities may seem unlikely candidates for a viable whale-watching industry, because of the prevalent traditional consumptive attitudes towards marine mammals and their uses. The topic of this paper is the introduction of an internationally growing industry of whale watching in a fishing village in north-east Iceland, and how local inhabitants reconcile opposing views on whales, whaling and the new cetacean tourism. The paper also discusses the conflict between fishermen and marine mammals, and how it is managed in an area where fishing is still a mainstay of the economy, and where marine mammals are seen by many as competitors for scarce resources, and even as pests. This anthropological case study is used to address wider issues of adaptation, community viability and resilience in small resource-dependent coastal settlements, coping with rapid social and ecological change.

From good to eat to good to watch: whale watching, adaptation and change in Icelandic fishing communities

Arctic and North Atlantic fishing communities may seem unlikely candidates for a viable whale-watching industry, because of the prevalent traditional consumptive attitudes towards marine mammals and their uses. The topic of this paper is the introduction of an internationally growing industry of whale watching in a fishing village in north-east Iceland, and how local inhabitants reconcile opposing views on whales, whaling and the new cetacean tourism. The paper also discusses the conflict between fishermen and marine mammals, and how it is managed in an area where fishing is still a mainstay of the economy, and where marine mammals are seen by many as competitors for scarce resources, and even as pests. This anthropological case study is used to address wider issues of adaptation, community viability and resilience in small resource-dependent coastal settlements, coping with rapid social and ecological change.