Journal: Polar Biology

Abbreviation

Polar Biol

Publisher

Springer

Journal Volumes

ISSN

1432-2056
0722-4060

Description

Filters

2013 - 201942020 - 20243
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Publications 1 - 7 of 7
  • Temperature modulates intra-plant growth of Salix polaris from a high Arctic site (Svalbard)
    Item type: Journal Article
    Buchwal, A.; Rachlewicz, G.; Fonti, P.; et al. (2013)
    Polar Biology
  • Year-round population dynamics of Limacina spp. early stages in a high-Arctic fjord (Adventfjorden, Svalbard)
    Item type: Journal Article
    Boissonnot, Lauris; Kohnert, Peter; Ehrenfels, Benedikt; et al. (2021)
    Polar Biology
    The thecosome pteropods Limacina helicina and L. retroversa are important contributors to the zooplankton community in high-latitude environments but little is known about their distribution and life cycle under polar conditions. We collected the early life stages (< 1 mm) of the thecosome population in 2012 and 2013 at a bi-weekly to monthly resolution in fjord highly influenced by Arctic waters as well as Atlantic inflows (Adventfjorden, Svalbard, 78°N), together with environmental parameters. L. retroversa only occurred episodically, in association with the inflow of Atlantic water, with low numbers and random size distributions. This suggests that this boreal species does not fulfill its life cycle in Adventfjorden. In contrast, young specimens of L. helicina were present during the entire study. Veligers hatched in late summer/autumn and measured 0.14 mm on average. They grew with rates of 0.0006 mm day−1 over the 10–11 months of development. Only thereafter, growth accelerated by one order of magnitude and maximal rates were reached in autumn (0.0077 mm day−1). Our results indicate that L. helicina reaches a size of 1 mm after approximately 1.5 years in Adventfjorden. We therefore suggest that L. helicina overwinters the first year as a small juvenile and that it needs at least 2 years to reach an adult size of 5 mm in Adventfjorden. This reveals an complex and delicate aspect of the life-cycle of L. helicina and further research is needed to determine if it makes the population especially vulnerable towards climate changes.
  • Environmental drivers of eukaryotic plankton and fish biodiversity in an Arctic fjord
    Item type: Journal Article
    Marques, Virginie; Hassler, Christel; Deiner, Kristy; et al. (2023)
    Polar Biology
    Arctic fjords are experiencing rapid environmental shifts due to climate change, which may have significant impacts on marine biodiversity and ecosystem functioning. However, the impact of climate change on fjord biodiversity is difficult to quantify given the low accessibility and high cost to sample these areas. In this study, we sampled locations from inside to outside an Arctic fjord and used environmental DNA metabarcoding to assess how the biodiversity of fish and eukaryotic plankton communities relate with environmental conditions. We detected a total of 12 fish taxa and 872 MOTUs for eukaryotes and found marked gradients of temperature and salinity driven by the distance to the glacier at the terminal part of the fjord and depth. Eukaryotic richness was mainly associated with lower temperature and chlorophyll a. Moreover, co-inertia analyses showed a shared structure between eukaryotes assemblages and the environmental gradients. A partial association between eukaryote and fishes suggest a potential shared effect of environmental gradients among these taxa. Our findings provide a baseline for future studies to assess how these assemblages may be impacted by ongoing environmental changes and highlight how fjord ice loss and warming might shift environmental gradients and species distribution under climate change.
  • Diversity and functionality of soil prokaryotic communities in antarctic volcanic soils: insights from penguin-influenced environments
    Item type: Journal Article
    Segura, Diego; Jordaan, Karen; Díez, Beatriz; et al. (2024)
    Polar Biology
    In the nutrient-limited Antarctic terrestrial habitat, penguins transfer a significant amount of nutrients from the marine to the terrestrial ecosystem through their depositions (i.e., guano). This guano influences soil physicochemical properties, leading to the formation of ornithogenic soil rich in nutrients and organic matter. We hypothesize that soil prokaryotic communities will be strongly influenced by the contribution of nitrogenous nutrients from penguin rookeries, maintaining the influence over long distances. The objective was to establish how the soil prokaryotic diversity and community structure change with distance from a penguin colony, which provides large amounts of guano and nitrogenous compounds, and to study the effects of these nutrients on the functional role of these communities. Methods include volcanic soil sampling along a 1200 m transect from the penguin active rookery and the characterization of soil nutrient content and soil prokaryotic communities using 16S rRNA high-throughput amplicon sequencing. In contrast to our hypothesis, the results showed that the impact of guano from the penguin colony was restricted to the first 300 m. Probably because the penguin rookery was sheltered, strong wind and wind direction did not affect the transport of nutrients from the penguin rookery. Areas close to the penguin rookery were dominated by Proteobacteria and Bacteroidetes, while areas situated further away were dominated by Acidobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes, Nitrospirae, and Planctomycetes. Beta diversity analysis among the soil prokaryotic communities revealed a high degree of community heterogeneity, strongly associated with N compound characteristics (NH4, NO3, and %N), C, and pH. Inferences from N metabolism genes suggest a high potential of the microbial community for dissimilatory nitrate reduction genes (DNRA) to ammonium, assimilatory nitrate reduction (ANR), and denitrification. Although it is assumed that the nitrogenous compounds of the penguin colonies reach long distances and affect the prokaryotic community, this effect can vary with wind directions or the morphology of the site, reducing the impact of the guano over long distances, as our results indicate. On the other hand, functional predictions give some clues about the main actors in nitrogen cycling, through processes like dissimilatory nitrate reduction, assimilatory nitrate reduction, and denitrification.
  • Underwater photogrammetry in Antarctica: long-term observations in benthic ecosystems and legacy data rescue
    Item type: Journal Article
    Piazza, Paola; Cummings, Vonda; Guzzi, Alice; et al. (2019)
    Polar Biology
  • Comparative vegetation survey with focus on cryptogamic covers in the high Arctic along two differing catenas
    Item type: Journal Article
    Kern, Ramona; Hotter, Vivien; Frossard, Aline; et al. (2019)
    Polar Biology
  • Changes in phytoplankton bloom phenology over the North Water (NOW) polynya: a response to changing environmental conditions
    Item type: Journal Article
    Marchese, Christian; Albouy, Camille; Tremblay, Jean‑Éric; et al. (2017)
    Polar Biology
Publications 1 - 7 of 7