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The high Arctic, including the Svalbard archipelago in the North Atlantic, has been exposed to direct and indirect drivers of climatic change such as rising temperatures and associated changes in hydrology and nutrient fluxes. In addition, the number of migrating birds, particularly geese, increased remarkably in the Svalbard archipelago during the second half of the last century. The higher number of breeding birds potentially affects water quality and the biota in ponds and lakes. We aimed to investigate the potential influence of increasing goose abundance on trophic state, taxon richness, and species composition of freshwater communities in the high Arctic. We hypothesised that higher goose abundance affects the trophic state of shallow lakes and ponds and their taxon richness and species composition. We conducted a survey of selected ponds at Svalbard along a goose abundance gradient. We used the number of area‐specific goose droppings (range of 0–94 droppings m2) as a proxy of goose presence and measured proxies for productivity as well as taxon richness and composition of phytoplankton and invertebrate communities. Presence and abundance of geese were associated with higher productivity of ponds. Invertebrate and phytoplankton taxon richness correlated (positively) with goose abundance. Both phytoplankton and invertebrate taxon richness increased with increasing nitrogen (N) concentrations. Goose abundance significantly affected phytoplankton species composition, while concentrations of total‐N and total phosphorus (P) did not. Species composition of aquatic invertebrates was most strongly affected by goose abundance, but the effect of total‐N concentration was also significant. Increased goose abundance was associated with bird driven nutrient enrichment, increased phytoplankton and invertebrate taxon richness and changes of these biological communities. Thus, in addition to climate change, the higher abundances of large migratory water fowl in many polar areas may pose a major additional stress to arctic lakes and ponds. In fact, climate change and bird impact may interact, accelerating ongoing environmental change of arctic freshwater ecosystems.

This study was a joint campaign among Norwegian and Russian researchers . Both 24 partners were involved in preparing the study design, as well as participating in meetings, 25 fieldwork (2014 and 2015) and analyzing/reporting of collected material. We owe thanks to 26 UNIS (the University Centre in Svalbard), NPI (the Norwegian Polar Institute), the 27 Governor of Longyearbyen and all the people in Barentsburg and Pyramiden for their 28 valuable support during fieldwork. Thanks also to Olga L. Makarova who identified mites. 29The study of ecology and taxonomy of Cyclopoida (Copepoda) was supported by the 30 programme "Scientific bases for the creation of a national depository bank of living 31 Council of Norway projects; "Effect of climate change and related stressors on fresh and 36 brackish water ecosystems in Svalbard [227024]" and "The effect of nutrient input from 37 migrating birds on the succession of freshwater communities of different age in Svalbard 38 [246726]". 39 40 41 This is a post-peer-review, pre-copyedit version of an article published in Polar Biology. The final authenticated version is available online at: http://dx. Abstract 42The high Arctic is in a rapid transition due to climate change, and both direct 43 effects due to warming and an extended growing season, as well as an indirect effect 44 caused by increased bird activity and density (notably geese), strongly affect ponds and 45 lakes. Our study presents the hitherto most comprehensive data on invertebrate 46 freshwater diversity at Svalbard and had three main purposes: to provide a current 47 "baseline" of community composition, to compare current species distribution and 48 occurrence with older data to identify changes that have already occurred, and finally to 49 identify how diversity and community composition are related to the age of localities. 50To address these aims we conducted a survey of freshwater invertebrates in 75 ponds and 51 lakes at Svalbard in August 2014 and 2015. We provide a full report of the species 52 inventory for zooplankton, benthos and meiofauna. We also provide data for species that 53 have likely colonized the sites over the past decades. Finally, our study also clearly 54 demonstrates a diversity gradient related to ecosystem age and/or parameters 55 confounded with age (e.g. productivity), which may hint at the rate of colonization over 56 the time span from the oldest to the youngest localities.57 58 59 This is a post-peer-review, pre-copyedit version of an article published in Polar Biology. The final authenticated version is available online at: http://dx.doi.org/ 10.1007/s00300-018-2340-3.Few places on the planet have witnessed a more dramatic climate change than the 61 high Arctic, and this is expected to continue for the foreseeable future (IPCC 2013). The 62 loss of sea ice, together with increasing air and water temperatures, has also caused major 63 changes on terrestrial habitats such as of the Svalbard archipelago in the North 64 Atlantic (Bhatt et al. 2010). Climatic recordings on the ...

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Microplastic pollution has become one of the most pressing environmental issues. A fundamental criterion for risk assessment is the concentration of found microplastic that can be altered during microplastic isolating from the sample. Recovery rate (i.e. positive control) is an important feedback component that identifies accuracy, quality and efficiency of sample processing, same as physical and chemical impact. Here, using 100 µm red polystyrene (PS) beads we have tested some methodological steps that can be responsible for the possible microplastic losses during sample treatment and based on that, we provided a recovery rate threshold values. Our results support that the choice of the extraction method (vacuum filtration versus wet sieving) results in lower recoverability when vacuum filtration is used and that used separatory funnels size versus material amount impacts the efficiency or recoverability in density separation. We have also analysed microplastic recovery rate when different samples treatment steps from widely used isolation protocols (sediment and water) were applied and our results suggest that there are a number of factors affecting recovery rates, of which physical effects (loss by consecutive treatment steps due to material transfer) are more important than possible chemical degradation. Sample filtration method determines recovery rate from < 40 to > 80%. The number of sample processing steps involving transfer has a direct impact on recovery rate. As a measure of quality assurance, recovery rate thresholds are introduced.

Abstract. the studies of cyclops o.F. müller, 1776 have more than two centuries of tradition in Fennoscandinavia, yet, basic taxonomic questions remain unresolved and the limits of the distributional area are very poorly understood in the majority of the taxa (11+) occurring in the region. Based on the types and other materials we redescribe two species, C. lacustris G.o. sars, 1863 and C. bohater koźmiński, 1933, the latter being reported here for the first time from Fenno-scandinavia; lectotypes of both species have been designated herein. setulation characters of the antennal coxobasis-and maxillulary palp setae and P1 medial spine, as well as the spine formula of the terminal exopodal segments of the swimming legs (3433) in the adult female distinguish C. lacustris and C. bohater from their congeners. an identification key is provided to the Cyclops species of Fenno-scandinavia, including information about both the female and male morphology. although the limited material does not allow us to define the species range limits, our data nevertheless support a northern european distribution in C. lacustris, and northern and central european distribution in C. bohater, while the records from the southern Palearctic need further verification.

Diversity of macrobenthic communities was studied from water bodies and streams of Spitsbergen, Svalbard archipelago, Norway. All together 162 quantitative samples from different reģions of Spitsbergen were analysed in relation to environmental variables. Macrobenthic communities were found on all kinds of substrates (except for periglacial zone) representing wide range of biological communities: solid-bottom, soft-bottom, macrophytes and small brook associated. However, taxonomical structure is very simplified, with a particular dominants from Chironomidae family. The chironomids larvae dominated highly as for diversity, abundance and biomass. Overall macrobenthic communities were characteristic with remarkable dominance of one species and general omnipresent taxonomical scarcity (avg. 2.8 species per sample). All together we found 30 taxa. We distinguished 16 types of macrobenthis communities, characteristic with the dominance of different taxa: chironomids (11 types), oligochaete Enchytraeidae family (3), caddisfly Apatania zonella (1) and gammarid amphipod Gammarus setosus (1).As to environmental variables, temperature and pH had the most significant influence on the abundance of macrobenthic organisms.It is hypothesized that the structural convergence of different types of communities is their common response to extreme high Arctic living conditions. On the other hand, different chironomids may dominate in the same habitats and water bodies. This gives the effect of lower average similarity of communities and high β-diversity.

Cultural eutrophication, the process by which pollution due to human activity speeds up natural eutrophication, is a widespread and consequential issue. Here, we present the 85-year history of a small, initially Lobelia–Isoëtes dominated lake. The lake’s ecological deterioration was intensified by water pumping station activities when it received replenishment water for more than 10 years from a eutrophic lake through a pipe. In this study, we performed a paleolimnological assessment to determine how the lake’s ecosystem functioning changed over time. A multi-proxy (pollen, Cladocera, diatoms, and Chironomidae) approach was applied alongside a quantitative reconstruction of total phosphorus using diatom and hypolimnetic dissolved oxygen with chironomid-based transfer functions. The results of the biotic proxy were supplemented with a geochemical analysis. The results demonstrated significant changes in the lake community’s structure, its sediment composition, and its redox conditions due to increased eutrophication, water level fluctuations, and erosion. The additional nutrient load, particularly phosphorus, increased the abundance of planktonic eutrophic–hypereutrophic diatoms, the lake water’s transparency decreased, and hypolimnetic anoxia occurred. Cladocera, Chironomidae, and diatoms species indicated a community shift towards eutrophy, while the low trophy species were suppressed or disappeared.