Search results for "Arctic"
showing 10 items of 565 documents
Combined statistical and mechanistic modelling suggests food and temperature effects on survival of early life stages of Northeast Arctic cod (Gadus …
2015
Abstract Understanding the causes of the large interannual fluctuations in the recruitment to many marine fishes is a key challenge in fisheries ecology. We here propose that the combination of mechanistic and statistical modelling of the pelagic early life stages (ELS) prior to recruitment can be a powerful approach for improving our understanding of local-scale and population-scale dynamics. Specifically, this approach allows separating effects of ocean transport and survival, and thereby enhances the knowledge of the processes that regulate recruitment. We analyse data on the pelagic eggs, larvae and post-larvae of Northeast Arctic cod and on copepod nauplii, the main prey of the cod lar…
Poleward range expansion without a southern contraction in the ground beetle Agonum viridicupreum (Coleoptera, Carabidae)
2011
We investigated the extent of poleward shifts in the distribution range of Agonum viridicupreum due to climate change in the western Palaearctic. Species' records were obtained from extensive literature sources as well as from collections, and consistent amateur entomologists' recordings. Within the general geographic range of the species, we analyzed in detail two parts of both, the northern and southern distribution range boundaries: (1 and 2) north-western Germany (leading or high-latitude edge), (3) Israel and (4) southern Italy (rear or low-latitude edge). Temporal changes in the occurrence data of the species indicated a northward shift of the leading edge of a minimum of 100 km withi…
First Nearctic Record of Hydrellia albilabris (Meigen) (Diptera: Ephydridae), a Leafminer of Duckweed (Araceae: Lemnoideae), with Comments on Related…
2019
Hydrellia albilabris (Meigen) (Diptera: Ephydridae) is recorded in the Nearctic Region for the first time. Its biology and immature stages are documented, and other miners in duckweeds (Araceae: Lemnoideae) are discussed. One new combination is proposed: Hydrellia jinpingensis (Zhang, Yang, and Hayashi) is transferred from Cavatorella.
One Species, Hundreds of Subspecies? New Insight into the Intraspecific Classification of the Old World Swallowtail (Papilio machaon Linnaeus , 1758)…
2022
The Old World swallowtail Papilio machaon Linnaeus, 1758 is one of the most well-known and most characteristic members of the family Papilionidae. Over the past two centuries, the butterfly has been the subject of many studies. P. machaon is characterised by a tendency to change the wing colour pattern. In turn, due to the great interest of collectors and amateur entomologists, these studies have been converted into the description of over 100 colour forms, aberrations and subspecies. In this study, mitochondrial DNA (mtDNA), 16S rDNA and cytochrome b sequences were used to examine the correlation between the intraspecific classification and genetic structure of P. machaon. The study used 8…
A bug's life: Delving into the challenges of helminth microbiome studies.
2020
The body of vertebrates is inhabited by trillions of microorganisms, i.e. viruses, archaea, bacteria and unicellular eukaryotes, together referred to as the ‘microbiota’. Similarly, vertebrates also host a plethora of parasitic worms (the ‘macrobiota’), some of which share their environment with the microbiota inhabiting the gastrointestinal tract [1]. Complex interactions between the helminths and the gut microbiota have been associated with establishment of parasite infection, disease manifestations, and host immune-modulation [2, 3]. Remarkably, not only enteric helminths alter the 26 gut microbiome composition [4], but also the infection with blood flukes of the genus Schistosoma has be…
Investing in indigenous multilingualism in the Arctic
2018
Abstract This article explores the dynamics between language and identity categories and the boundaries produced in a changing multilingual, indigenous context in the Arctic region of Finland. In this moment of transition, indigenous multilingualism has high stakes. It can be a resource for political and economic development but also for management and regimentation, open to winners and losers. Drawing on a longitudinal critical discourse ethnography of producing language and identity categories in the Finnish Arctic, I discuss three circulating discourses relevant for the ways in which indigenous identity boundaries are made to matter, namely strategic, aspirational and affective multiling…
Conditions of commodification : Russian as a transient commodity in an Arctic tourism resort
2022
Abstract Based on an ethnography incorporating interview, linguistic landscape and observational data, this research illustrates how temporary linguistic value is negotiated and how an Arctic tourism destination is made fit for consumption for a specific audience. Set within a tourism resort in the Finnish Arctic during two weeks in Winter when the region habitually receives a large influx of Russian-speaking visitors, we illustrate how Russian is conceptualized as a means of economic practice by stakeholders in the local tourism industry. While some offer services specifically for a Russian-speaking audience as part of a short-term high-risk/high-reward investment, others regard Russian as…
Frozen actions in the Arctic linguistic landscape: a nexus analysis of language processes in visual space
2011
Abstract This article examines the linguistic landscape (LL) of seven villages above the Arctic Circle, in the region called North Calotte. The area forms a complex nexus of contested and changing multilingualism, particularly as regards to endangered indigenous Sami languages and Kven and Meankieli minority languages. Viewing LL as a discursively constructed space and consequently signs as ‘frozed actions’ by various actors, and by adopting a Nexus analytical approach we examine three interrelated aspects of Arctic LLs: (1) the synchronic aspect by addressing the question of how languages are used in the landscapes of northern villages in the year 2008; (2) the historical aspect through id…
Cloud top altitude retrieved from Lidar measurements during ACLOUD at 1 second resolution
2021
During the ACLOUD aircraft campaign (23.5.2017 - 26.6.2017) the AMALi Lidar was installed mostly nadir pointing. This dataset contains the cloud top altitude from those measurements (altitudes with a strong signal increase) as well as a cloud mask, derived from the optical depth of the column at 1 second resolution. The majority of the data was collected northwest of the Svalbard archipelago. More details on the campaign can be found in Wendisch 2018 and Ehrlich 2019 and here (https://home.uni-leipzig.de/~ehrlich/ACLOUD_wiki_doku). Please check the data documentation (https://download.pangaea.de/reference/108729/attachments/readme_documentation_AMALi_cloudtop.pdf) before using this dataset.
Exposing the structure of an Arctic food web
2015
15 pages; International audience; How food webs are structured has major implications for their stability and dynamics. While poorly studied to date, arctic food webs are commonly assumed to be simple in structure, with few links per species. If this is the case, then different parts of the web may be weakly connected to each other, with populations and species united by only a low number of links. We provide the first highly resolved description of trophic link structure for a large part of a high-arctic food web. For this purpose, we apply a combination of recent techniques to describing the links between three predator guilds (insectivorous birds, spiders, and lepidopteran parasitoids) a…