Past Arctic aliens have passed away, current ones may stay

Published version. Source at http://doi.org/10.1007/s10530-015-0937-9.Increased human activity and climate change are expected to increase the numbers and impact of alien species in the Arctic, but knowledge of alien species is poor in most Arctic regions. Through field investigations over the last 10 years, and review of alien vascular plant records for the high Arctic Archipelago Svalbard over the past 130 years, we explored long term trends in persistence and phenology. In total, 448 observations of 105 taxa have been recorded from 28 sites. Recent surveys at 18 of these sites revealed that alien species had disappeared at half of them. Investigations at a further 49 sites characterised by former human activity and/or current tourist landing sites did not reveal any alien species. Patterns of alien species distribution suggest that greater alien species richness is more likely to be aligned with ongoing human inhabitation than sites of transient use. The probability of an alien species being in a more advanced phenological stage increased with higher mean July temperatures. As higher mean July temperatures are positively correlated with more recent year, the latter finding suggests a clear warming effect on the increased reproductive potential of alien plants, and thus an increased potential for spread in Svalbard. Given that both human activity and temperatures are expected to increase in the future, there is need to respond in policy and action to reduce the potential for further alien species introduction and spread in the Arctic

Stable Isotope Biogeochemistry of Seabird Guano Fertilization: Results from Growth Chamber Studies with Maize (Zea Mays)

Stable isotope analysis is being utilized with increasing regularity to examine a wide range of issues (diet, habitat use, migration) in ecology, geology, archaeology, and related disciplines. A crucial component to these studies is a thorough understanding of the range and causes of baseline isotopic variation, which is relatively poorly understood for nitrogen (δ(15)N). Animal excrement is known to impact plant δ(15)N values, but the effects of seabird guano have not been systematically studied from an agricultural or horticultural standpoint.This paper presents isotopic (δ(13)C and δ(15)N) and vital data for maize (Zea mays) fertilized with Peruvian seabird guano under controlled conditions. The level of (15)N enrichment in fertilized plants is very large, with δ(15)N values ranging between 25.5 and 44.7‰ depending on the tissue and amount of fertilizer applied; comparatively, control plant δ(15)N values ranged between -0.3 and 5.7‰. Intraplant and temporal variability in δ(15)N values were large, particularly for the guano-fertilized plants, which can be attributed to changes in the availability of guano-derived N over time, and the reliance of stored vs. absorbed N. Plant δ(13)C values were not significantly impacted by guano fertilization. High concentrations of seabird guano inhibited maize germination and maize growth. Moreover, high levels of seabird guano greatly impacted the N metabolism of the plants, resulting in significantly higher tissue N content, particularly in the stalk.The results presented in this study demonstrate the very large impact of seabird guano on maize δ(15)N values. The use of seabird guano as a fertilizer can thus be traced using stable isotope analysis in food chemistry applications (certification of organic inputs). Furthermore, the fertilization of maize with seabird guano creates an isotopic signature very similar to a high-trophic level marine resource, which must be considered when interpreting isotopic data from archaeological material

Eco-geographical relations of the Bjørnøya vasular flora, Svalbard

A renewed survey of the flora of Bjemeya (74" 31") has yielded a total of 54 native vascular species. Details of their distribution are provided by local maps and vertical frequency tabulations. Soil preferences of species and various plant communities are outlined. The general climate and microthermal conditions of the prevailing vegetation place Bjørnøya as a pronouncedly maritime part of the Svalbard archipelago, supporting mainly hygrophilous and chionophilous plant communitites and species. Only half of the island's vascular species persist at elevations above 200 m a.s.l., corresponding to a heat sum of July and August below approximately 190 Degree-Days. Ice-cored peat mounds coated by Rharomitrium lanuginosum were discovered on plateaux above 400 m elevation. The impact of the Vistula glaciation is discussed in view of Quaternary evidence from the Barents Sea area. Probably only one third of the present vascular flora could endure full-glacial conditions in possible ice-free cliffs on the coast of Bjørnøya

Vev og nettverk, tekst og tidrom: Liv Lundbergs roman «Nybegynnerens forutsetningsløshet»

[…][…][…

Botany of two Antarctic mountain ranges: Gjelsvikfjella and Mühlig-Hofmannfjella, Dronning Maud Land

The investigated area is located between 71"45' and 72"20'S and between l"35' and 5"33'E, from 1,080 to 2,695 m above sea level. An outline of climate, soil chemistry and main units of vegetation is provided. Of particular importance is the wet oasis area of Jutulsessen in Gjelsvikfjella which supports cyanophyceans, green algae, lichens and the mosses Grimmia lawiana and Sarconeurum glaciale, which have developed a series of distinctive communities. The nunataks fringing the Polar plateau harbour an impoverished cyanophycean and lichen vegetation up to approximately 2,500 m a.s.l., which is the highest elevation that macroscopic plant life has hitherto been reported in Antarctica. The thermal relations of the vegetation are discussed, based on the climatological record and on local measurements during the Norwegian Antarctic Research Expedition 1984/85. Some zonal and vertical belt subdivisions are indicated for this part of Greater Antarctica

Barndommens bøker i menns verden: «Guttene fra Gokkohjørnet» (1959) av Egil Rasmussen

Egil Rasmussen debuterte allerede som 20-åring med romanen Østen og Vesten (1923), og da han døde 18. juni 1964, bare 61 år gammel, hadde han skrevet 13 romaner (…).Egil Rasmussen debuterte allerede som 20-åring med romanen Østen og Vesten (1923), og da han døde 18. juni 1964, bare 61 år gammel, hadde han skrevet 13 romaner (…).Egil Rasmussen debuterte allerede som 20-åring med romanen Østen og Vesten (1923), og da han døde 18. juni 1964, bare 61 år gammel, hadde han skrevet 13 romaner (…)

Barndommens bøker i menns verden. <i>Guttene fra Gokkohjørnet</i> (1959) av Egil Rasmussen

Egil Rasmussen debuterte allerede som 20-åring med romanen Østen og Vesten&nbsp;(1923), og da han døde 18. juni 1964, bare 61 år gammel, hadde han skrevet 13 romaner (…).Egil Rasmussen debuterte allerede som 20-åring med romanen Østen og Vesten&nbsp;(1923), og da han døde 18. juni 1964, bare 61 år gammel, hadde han skrevet 13 romaner (…).Egil Rasmussen debuterte allerede som 20-åring med romanen Østen og Vesten&nbsp;(1923), og da han døde 18. juni 1964, bare 61 år gammel, hadde han skrevet 13 romaner (…)