Dialogue about “learning” across the Northern Norway-Russia border: An analysis of textbooks in kindergarten teacher education

This paper is the first in a series of three studies that explore the pedagogy used in the Norwegian and Russian early childhood settings by examining texts that are part of the syllabus in two early childhood teacher education programs that participated in our project with student international exchanges. The study explores how Mikhail Bakhtin’s notion of dialogue relates to the concept of ‘learning’ in the context of early childhood teacher educations in Northern Norway and Northern Russia. The data sources are textbooks used as syllabi for kindergarten teacher education in those countries. These national dialogues are understood as authoritative discourses on the concepts of learning to which the students in both countries have to relate. By being inspired by Bakhtin’s notion of dialogue, we consider that the ideas in textbooks areas are in a dialogic relationship as they are parts of a regulating battle between centrifugal and centripetal forces. A constructivist perspective on learning and the division of the learning process into subject, knowledge and education areas are identified as the centripetal forces in the dialogue on learning. Activities, tools, and the role of adults are identified as centrifugal forces. Based on the hypothetical premise that textbooks influence practices and that practice may unfold as textbooks describe, we have created hypothetical discussions between educators and students in these countries. The study provides better insight on the premises for the dialogue about learning across international borders which can be useful in internalization and exchange programs in kindergarten teacher educations in different countries

Size-fractioned zooplankton biomass in the Barents Sea: Spatial patterns and temporal variations during three decades of warming and strong fluctuations of the capelin stock (1989–2020)

Zooplankton biomass has been monitored on joint Norwegian-Russian surveys in late summer and autumn since the 1980s. We report here on zooplankton biomass in three size fractions ( 2 mm in screen mesh opening) obtained with WP-2 plankton net (180 μm mesh size) hauled vertically over the water column from near bottom to the surface for the period 1989–2020. The number of samples (stations) collected each year has been about 100–200, with a total number of 4543 stations for the whole data set. The size composition of zooplankton reflected by the three fractions has shown remarkable stability, with about 50% of biomass contained in the medium fraction (made up largely of Calanus species), about 1/3 in the small fraction (36%), and 16% in the large fraction. The depth integrated biomass was generally larger in basins compared to shallower bank areas. The temporal (interannual) pattern of change was characterized by a marked peak in biomass in 1994 and 1995 with values up to >20 g dry weight (dw) m−2, driven to large extent by the small size fraction. Subsequently the biomass decreased to lower values but with a divergence of relatively high values (10–15 g dw m−2) in the inflow area of Atlantic water in southwest, and low values (2–6 g dw m−2) in the central area. The difference is interpreted to reflect an increase in a second summer generation of Calanus finmarchicus in the Atlantic water and a decrease of C. glacialis in the central area. The zooplankton biomass fluctuated inversely with the biomass of the Barents Sea capelin (Mallotus villosus) stock, reflecting a top-down predation effect. However, biomass was also negatively correlated with temperature of the Atlantic water, suggesting an additional and confounding effect of climate variability and change. The decrease in biomass of the central area used as a forage area by capelin, was associated with a shift to dominance by the small size fraction. This is likely an effect of predation and could be associated with a lower trophic conversion efficiency from phytoplankton to planktivorous fish and higher trophic levels by smaller zooplankton (smaller copepods such as Pseudocalanus and others) compared to the larger Calanus species.publishedVersio

Abundance and mortality of Northeast Arctic cod and haddock during their first years of life

For Northeast Arctic cod and haddock in the Barents Sea, long time series of year-class abundance are available at several stages before they recruit to the fishery, i. e. before they reach age 3. Several studies have already been made of the influence of various factors on the abundance and survival of these stocks during the first three years of life, in particular for cod. However, revision of existing data series as well as availability of longer data series makes a new analysis worthwhile. The analysis includes VPA estimates of recruitment, as well as estimates of total egg production and survey estimates from pelagic and bottom trawl surveys. The mortality between various life stages is found to vary considerably between cohorts for both stocks. Although and the mortality is highest during the first months of life, the year-class strength can also be affected considerably by processes taking place between the 0-group stage (ca. 6 months) and age 3. The mortality in this period of life seems to be strongly density –dependent for both stocks. The estimates of 0- and 1-group abundance of cod and haddock from different sources (0-group pelagic trawl and acoustic, 1-group XSA and trawl) give numbers which are compatible with each other. The ratio between haddock and cod recruitment at age 3 is higher in the period after 1980 than before 1980, this may be due to higher temperature in the latter period. High haddock recruitment never occurs when cod recruitment is low

Polar cod in jeopardy under the retreating Arctic sea ice

The Arctic amplification of global warming is causing the Arctic-Atlantic ice edge to retreat at unprecedented rates. Here we show how variability and change in sea ice cover in the Barents Sea, the largest shelf sea of the Arctic, affect the population dynamics of a keystone species of the ice-associated food web, the polar cod (Boreogadus saida). The data-driven biophysical model of polar cod early life stages assembled here predicts a strong mechanistic link between survival and variation in ice cover and temperature, suggesting imminent recruitment collapse should the observed ice-reduction and heating continue. Backtracking of drifting eggs and larvae from observations also demonstrates a northward retreat of one of two clearly defined spawning assemblages, possibly in response to warming. With annual to decadal ice-predictions under development the mechanistic physical-biological links presented here represent a powerful tool for making long-term predictions for the propagation of polar cod stocks.publishedVersio

Key processes regulating the early life history of Barents Sea polar cod

The polar cod (Boreogadus saida) in the Barents Sea is one of the main stocks of this species in the Arctic, reaching a total biomass of almost 2 million tonnes in some years. It has been fluctuating considerably in abundance, and in recent years, it has been at a low level. Only small catches have been taken from the stock over the last four decades, and consequently, the observed variation in abundance must be caused by natural (environmental and/or biological) changes in the ecosystem. Sea temperatures have been rising in the Barents Sea in recent years, possibly causing changes to the living conditions of this true Arctic stock. Consequently, there is a need for investigating how the observed changes might affect polar cod in this area. One important aspect of the environmental impact on the stock is possible effect on the recruitment, which has been varying considerably from year to year. In this modelling study, we thus recreate and analyse the environmental and developmental histories of the observed 0-group individuals in the Barents Sea (young of the year), with emphasis on the importance of ice cover, ice breakup time, maximum temperature, and spawning stock biomass. Our simulations indicate that the environmental conditions experienced by individuals successfully “recruited” to the 0-group are characterized by high ice concentration well into summer, and low temperatures throughout the pelagic juvenile phase, and any perturbations from the Arctic ocean climate typically found in the northern and eastern Barents Sea appears to be detrimental to stock recruitment. In light of the projected warming of the Barents Sea in the next decades and the potential reduction in ice cover, this will entail, the mechanisms investigated herein might lead to future marginalization of polar cod in the Barents Sea.publishedVersio

Ecosystem-related monitoring, assessments and management advices for the Norwegian, Barents and North Seas

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Recruitment variability of fish stocks in the Barents Sea: Spatial and temporal variation in 0-group fish length of six commercial species during recent decades of warming (1980–2017)

Young-of-the-year (0-group) fish in the Barents Sea have been investigated in an annual joint Norwegian-Russian pelagic trawl survey in autumn, using a standardized procedure since 1980. We use a conceptual framework of ‘upstream’ spawning areas and ‘downstream’ nursery areas, recorded as 0-group distribution in the Barents Sea, to address spatial (geographical) and temporal (1980–2017) variation in 0-group length. Four boreal species (cod Gadus morhua, haddock Melanogrammus aeglefinus, herring Clupea harengus, and deepwater redfish Sebastes mentella) tended to have smaller 0-group individuals in the northern and eastern parts of the Barents Sea, with the largest individuals found in the central part where they were also most abundant. We interpret this to reflect slower growth as the ‘fore-runners’ of the seasonal cohort of juveniles are transported into colder waters (through lateral mixing). The Arctic species (capelin Mallotus villosus and polar cod Boreogadus saida) showed a different pattern with increasing 0-group length with increasing distance away from the spawning areas, seen most clearly for capelin. The longer juveniles in northern areas are probably older and stemming from early spawning.publishedVersio