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- Coulson, S. J., et al.
(författare)
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Introduction of invertebrates into the High Arctic via imported soils: the case of Barentsburg in the Svalbard
- 2013
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Ingår i: Biological Invasions. - : Springer Science and Business Media LLC. - 1387-3547 .- 1573-1464. ; 15:1, s. 1-5
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Tidskriftsartikel (refereegranskat)abstract
- Forty six species of invertebrate were collected from the manure enriched imported soils below the abandoned cow sheds in the Russian mining town of Barentsburg, Svalbard. Of these, 11 (24 %) were new records for Svalbard, including Collembola, gamasid mites, Enchytraeidae and the first identified Lumbricidae. Many of the new records are species not frequently observed in the Arctic. It is hypothesized that these species arrived with the chernozem soils imported to Barentsburg for the greenhouses from central or southern European Russia, or with livestock. The observations presented here are the first records of human invertebrate introductions establishing in Svalbard outside of dwellings. It is not believed that the majority of new species records described present an immediate threat to the ecology of Svalbard but they may, especially Deuteraphorura variabilis, establish in the nutrient enriched floral communities beneath bird cliffs characteristic of Svalbard.
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- Coulson, S. J., et al.
(författare)
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The invertebrate fauna of anthropogenic soils in the High-Arctic settlement of Barentsburg, Svalbard
- 2013
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Ingår i: Polar Research. - : Norwegian Polar Institute. - 0800-0395 .- 1751-8369. ; 32
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Tidskriftsartikel (refereegranskat)abstract
- The terrestrial environment of the High Arctic consists of a mosaic of habitat types. In addition to the natural habitat diversity, various human-influenced types may occur. For the resident invertebrate fauna, these anthropogenic habitats may be either unusually favourable or detrimental. In the town of Barentsburg, Svalbard, soils were imported for the greenhouses from southern Russia. These soils were subsequently discarded outside the greenhouses and have become augmented with manure from the cowsheds. Both the greenhouse and the cowsheds are now derelict. This site represents an unusually nutrient-rich location with considerable development of organic soils, in stark contrast to the naturally forming organic soils in Svalbard, which are typically thin and nutrient poor. Few previous studies have examined the soil invertebrate communities of human-disturbed or -created habitats in the Arctic. In an often nutrient-poor terrestrial environment, it is unclear how the invertebrate fauna will react to such nutrient enhancement. In these soils, 46 species of invertebrates were determined. Eleven species have not been recorded from other habitats in Svalbard and are hence likely to have been introduced. The native species assemblage in the anthropogenic soils was not atypical for many natural sites in Svalbard. Despite the enriched organic soils and highly ameliorated winter temperature conditions, the soil invertebrate fauna biodiversity does not appear to be enhanced beyond the presence of certain probably introduced species.
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- Song, Jia L, et al.
(författare)
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Select microRNAs are essential for early development in the sea urchin
- 2012
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Ingår i: Developmental Biology. - : Elsevier. - 0012-1606 .- 1095-564X. ; 362:1
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Tidskriftsartikel (refereegranskat)abstract
- microRNAs (miRNAs) are small noncoding RNAs that mediate post-transcriptional gene regulation and have emerged as essential regulators of many developmental events. The transcriptional network during early embryogenesis of the purple sea urchin, Strongylocentrotus purpuratus, is well described and can serve as an excellent model to test functional contributions of miRNAs in embryogenesis. We examined the loss of function phenotypes of major components of the miRNA biogenesis pathway. Inhibition of de novo synthesis of Drosha and Dicer in the embryo led to consistent developmental defects, a failure to gastrulate, and embryonic lethality, including changes in the steady state levels of transcription factors and signaling molecules involved in germ layer specification. We annotated and profiled small RNA expression from the ovary and several early embryonic stages by deep sequencing followed by computational analysis. miRNAs as well as a large population of putative piRNAs (piwi-interacting RNAs) had dynamic accumulation profiles through early development. Defects in morphogenesis caused by loss of Drosha could be rescued with four miRNAs. Taken together our results indicate that post-transcriptional gene regulation directed by miRNAs is functionally important for early embryogenesis and is an integral part of the early embryonic gene regulatory network in S. purpuratus.
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