Iron, manganese, and trace elements play an important role in the marine carbon cycle as they are limiting nutrients for marine primary productivity. Water column concentrations of these ...bio-essential elements are controlled by the balance between input and removal, with burial in marine sediments being the main sink. The efficiency of this burial sink is dependent on the redox state of the water column, with sediments underlying a sulphidic (euxinic) water column being the most efficient sinks for Fe, but also Mn and trace elements (Co, Cd, Ni, Mo, As, W, V, and U). Transient changes in ocean redox state can hence affect trace element burial, and correspondingly, the ocean’s trace element inventory, but the impact of transient oxygenation events on trace element cycling is currently not well understood.
Here, we investigate the impact of a natural oxygenation event on trace element release and burial in sediments of the Eastern Gotland Basin (EGB), a sub-basin of the Baltic Sea. After being anoxic (<0.5 µM O2) for ∼10 years, the deep waters of the EGB experienced a natural oxygenation event (Major Baltic Inflow, MBI) in 2015. Following this oxygenation event, we deployed benthic chamber landers along a depth transect in the EGB in April 2016, 2017 and 2018. We complemented these in situ flux measurements with analyses of water column, solid phase and pore water chemistry. Overall, the event increased the benthic effluxes of dissolved trace elements, though particular responses were element-specific and were caused by different mechanisms. Enhanced fluxes of Cd and U were caused by oxidative remobilisation, while Ni showed little response to the inflow of oxygen. In contrast, enhanced release of Co, Mo, As, W, and V was caused by the enhanced transient input of Mn oxides into the sediment, whereas Fe oxides were of minor importance. Following the dissolution of the oxides in the sediment, Mn and W were nearly completely recycled back to the water column, while fractions of Fe, Co, Mo, As, and V were retained in the sediment. Our results suggest that transient oxygenation events in euxinic basins may decrease the water column inventory of certain trace elements (Fe, Co, Mo, As, and V), thus potentially affecting global marine primary productivity on longer timescales.
The deep basins of the Baltic Sea experienced dramatic climate- and eutrophication-induced redox changes between oxic and euxinic water column conditions. Irregularly appearing Major Baltic Inflows ...(MBI) carrying North Sea waters to the Baltic Sea are partly able to oxygenate euxinic bottom waters within several weeks. After an absence of ~10 years, an exceptional strong inflow event in December 2014 reached the Gotland Basin in early March 2015 providing the opportunity of detailed studies on the impact of fast redox shifts on elemental cycles. Here we report on P and trace metal (Co, Mo, U, V and W) dynamics in the water column, pore water, and sediment of the central Gotland Basin over a 4.5 year-long observation period. These time series record the entire redox development including the primary MBI-related oxygenation, the transitional development to anoxia before a second inflow pulse, and the final re-establishment of euxinia. Samples obtained in August 2012 represent the previous euxinic stagnation period not affected by MBI's since nearly a decade. Concentration measurements and a budget calculation suggest only a limited impact of the MBI on the water column P inventory and the corresponding eutrophication level of the Gotland Basin. This is due to insufficient Fe availability preventing efficient trapping of phosphate during water column oxygenation. In addition, the fast recovery of reducing conditions allowed only a short-term storage of deposited Mn–Fe–P mineral phases in the surface sediment. Due to pronounced scavenging by Mn oxides, substantial water column depletion occurred intermittently for V and W, but again, re-establishing reducing conditions favored Mn oxide dissolution and the release especially of W back into the water column. Mo and U were less affected by Mn and Fe shuttling and Mo even showed an increasing water column inventory due to replenishment by intruding North Sea waters. In contrast, the water column inventory of Co remained on an approx. 50% level about 4.5 years after the inflow suggesting a significant sedimentary burial of Co within the course of the inflow event. Although sedimentary Mn carbonate layers, which were commonly formed in concert with the frequent inflows between ~1960 and 1980, were missing or only weakly developed after the single inflow events in 1994, 2003, and 2014, dated short cores from the study area reveal clear Co and less pronounced V enrichments during the latter inflows. Because Mo, U and W are synchronously depleted compared with their normal sapropel levels, the combination of these trace metals and Co may help to identify past MBIs not reflected by Mn carbonate presence.
•Inflow-related dynamics of P and trace metals were studied in the Gotland Basin.•Limited impact of water column oxygenation on P inventory during a 4.5 year period.•Intruding North Sea waters replenished Mo and U water column inventories.•A substantial fraction of Co and V was retained in the sediments after the inflow.•Different sediment signatures of Co, Mo, U, and W serve as proxy for past inflows.
При изучении развития костюма в разных странах, особенно в Европе, пока нет исследований, посвященных скандинавскому костюму Вендельской эпохи (во время которой в Гробиня была основана скандинавская ...колония). К сожалению, в это время в Скандинавии основным способом женских захоронений является кремация, в результате чего находки тканей являются редкостью, а прямые находки костюмов отсутствуют. Задача этой статьи – охарактеризовать возможные детали женского костюма, основываясь на находках из Гробиня, с острова Готланд и континентальной части Швеции, включая анализ возможного воздействия куршей на костюм в колонии в Гробиня. В то же время необходимо отметить, что эта реконструкция основана только на археологических находках и является гипотетической.
In the study of development of costume in different countries and especially in Europe, no special studies have been conducted concerning the costume during Scandinavian Vendel period, which coincides with the time when a Norse colony was founded in Grobiņa. Unfortunately, like in the rest of Scandinavia, women were usually cremated, so that the textile finds are few in number and there is no direct evidence of the dress. The aim of the paper is to characterize the possible details of women’s dress on the basis of the information from Grobiņa, Gotland and mainland Sweden, including analysis of the possible Curonian influence on the costume in the Grobiņa colony. It should be noted, however, that this hypothesis is based only on the archaeological discoveries, and the proposed reconstruction is therefore hypothetical.
Removal of fixed nitrogen in the water column of the eastern Gotland Basin, central Baltic Sea, was studied during two cruises in September 2008 and August 2010. The water column was stratified with ...anoxic sulfidic bottom water meeting oxic nitrate containing water at the oxic–anoxic interface. Anammox was never detected whereas denitrification was found in all incubations from anoxic depths and occurred immediately below the oxic–anoxic interface. Sulfide (H2S+HS−+S2−) was in most cases the only electron donor for denitrification but, in contrast to previous findings, denitrification was in some situations driven by organic matter alone. Nitrous oxide (N2O) became an increasingly important product of denitrification with increasing sulfide concentration and was >80% of the total N gas formation at 10μM sulfide. The potential rates of denitrification measured in incubations at elevated NO3- or sulfide concentrations were converted to in situ rates using the measured water column concentrations of NO3- and sulfide and the actual measured relations between NO3- and sulfide concentrations and denitrification rates. In situ denitrification ranged from 0.24 to 15.9nMN2h−1. Assuming that these rates were valid throughout the anoxic NO3- containing zone, depth integrated in situ denitrification rates of 0.06–2.11mmol Nm−2d−1 were estimated. The thickness of this zone was generally 3–6m, which is probably what can be maintained through regular turbulent mixing induced by internal waves at the oxic–anoxic interface. However, layers of up to 55m thickness with low O2 water (<10μM) were observed which was probably the result of larger scale mixing. In such a layer nitrification may produce NO3- and once the O2 has been depleted denitrification will follow resulting in enormous rates per unit area. Even with an active denitrification layer of 3–6m thickness the pelagic denitrification per unit area clearly exceeded sediment denitrification rates elsewhere in the Baltic Sea. When extrapolated to the entire Baltic Proper (BP) denitrification in the water column was in the range of 132–547ktonNyr−1 and was thus at least as important as sediment denitrification which has recently been estimated to 191ktonNyr−1. With a total external N-input of 773ktonNyr−1 it is clear that denitrification plays a significant role in the N-budget of the BP.
•Trans-Baltic geological and geophysical correlations connect the Precambrian across the Baltic Sea.•Two major deformation zones divide Gotland into three NE-SW younging segments.•A potential ...continuation of the Riga batholith is observed on northern Gotland.•Detrital zircons on northern Gotland show a specific provenance pattern without < 1.9 Ga ages.
Gotland is an island in the central part of the Baltic Sea, with up to 800 m Palaeozoic sedimentary rocks on top of a Precambrian basement belonging to the East European Craton. In this contribution, two major ductile deformation zones (Lickershamn - Östergarn and Lilla Karlsö-Ronehamn) are recognized and connected with the Vingåker-Nyköping and Linköping-Loftahammar Deformation Zones in the adjacent Fennoscandian Shield. These deformation zones constitute the borders between three main Precambrian segments that are correlated with crustal units within the Fennoscandian Shield and concealed parts of the East European Craton east of the Baltic Sea.
The Fårö-Northern Gotland segment is dominated by continental Jotnian sandstones and Svecofennian metasedimentary rocks, separated from each other by a fault and an associated dolerite dyke. The metasediments show a specific provenance pattern with 3.29 Ga, 2.95–2.63 Ga and 2.11–1.96 Ga sources, devoid of < 1.90 Ga detrital zircons. The Alby granite truncates the metasedimentary rocks of the Fårö-Northern Gotland segment and is part of the 1.58 Ga Riga rapakivi batholith. The Central Gotland segment is dominated by metabasalts and 1.90–1.88 Ga granitoids and is correlated with the Tiveden and Valdemarsvik areas in the Fennoscandian Shield. The amphibolites in the Southern Gotland segment are correlated with 1.87–1.86 Ga metabasalts, intercalated with the Västervik quartzites in the Fennoscandian Shield. They were intruded by TIB 0 granitoids, recognized at Frigsarve and correlated with the Askersund-Loftahammar granitoids in the Fennoscandian Shield. The TIB 0 granitoids on Gotland can also be followed to the east, first to the E6-1 offshore drill hole, 30 km west of the Latvian coast and further east into southwestern Latvia and western Lithuania as a major component in the Mid-Lithuanian Domain. The Kvarne granitoid on southernmost Gotland is correlated with the TIB 1a generation in the Fennoscandian Shield and with granitoids within the Mid-Lithuanian Domain.
1.48 Ga small stitching plutons on southern Gotland penetrate the TIB 0 and 1a granitoids and are correlated with the Götemar and Karlshamn plutons in the Fennoscandian Shield and several plutons in western and southern Lithuania.
This article is based on a qualitative study regarding two World Heritage Island destinations, Gotland in the Baltic Sea and Rapa Nui in the Pacific Ocean. The two islands are used as cases ...illustrating different views on the development of cruise tourism. By applying conjunctural analysis the authors are able to account for the broader context of cruise tourism. Different perspectives on cruise tourism are found to be embedded in both local and global contexts, which are associated with three kinds of challenges: cruise tourism is developing without the local community’s involvement in decision making, it is not aligned with the aims of local tourism and ignores local products and services. We therefore call for more involvement of the local community in the development of cruise tourism.
In Rone church on Gotland there was once a runic inscription scratched into the inner wall of chancel (G 54C). The inscription is now lost, but it was documented and published by Hugo Pipping in the ...year 1900. According to Pipping the meaning was Ráð rún eptir harm-b-raðum “Read the inscription after the sad lines”. Little attention has been paid to the inscription since then, but in 2002 Evert Salberger and Thorgunn Snædal independently of each other came up with new interpretations of this inscription, partly based on OWN word material. Salberger suggests “Read the runes after mischiefs” comprising a counterpart to the word harmbrǫgðom known from Atlakviða 15, whereas Snædal assumed a word harmbrāðr with the meaning ‘quick to grieve’. The present study is based on the discovery that the same text is recorded also in a plaster inscription in Lye church on Gotland (G 104Eg). By comparing this inscription with the documentation of the runes in Rone (a drawing and some photographs) it is possible to reconstruct the original text, which seems be: Rāð rūnir ok blīg(a), armbr, augum! “Read the runes and stare, wretched, with the eyes!”. According to this suggestion the inscriptions contain a direct counterpart to the OWN expression blígja augum “stare with a fixed gaze”. The aim of the text was probably to invite the readers to interpret the runes and then mocking them for foolishly staring into the wall.
Archaeology and heritage, in whatever form, can be understood today as either the past that should be managed as something outside the present and by pro- fessionals who shape a master narrative, or ...as some- thing present and open to a diversity of interpretations and narrations in the present. In this text I will exam- ine the consequences of both these perspectives and end with the conclusion that it is a question of ontolog- ical care, the kind of care which, by means of a criti- cal narrative, must be open to all the stories involved.
The style and iconography of two wellknown picture stones are reanalysed. The Hablingbo Havor II pic ture stone shows a motif that occurs frequently in Got landic art from the Vendel Period ...onwards: the“Water Dragon”. It is suggested that this relates to an ideo logical connection between the dragon and the sea, where the sea is the dragon that ferries ships to distant shores. This is reflected not only in picture stones, but in Viking Age art in general. The iconography of När Smiss III (the “Snake Witch”) has been interpreted in a variety of ways, but special consideration is given to Peel’s (1999) suggestion that it relates closely to the Vi tastjärna myth from the 13thcentury Guta Saga. The artistic style of the zoomorphs on both stones (Style II) is typically dated to the Vendel Period. It is suggested that Sune Lindqvist’s insistence that the stones date from before AD 600 comes from a longstanding de bate with Nils Åberg over the date and context of the east mound at Uppsala, and by association, the date of the artistic style found on Hablingbo Havor II and När Smiss III. This debate has been resolved in favour of Åberg’s interpretation. These two picture stones rep resent an artistic tradition that should be dated con servatively from the beginning of the 5th century AD to the middle of the 7th century AD.
PDF
