Search results for "jää"

Phylogeography, evolutionary history and effects of glaciations in a species (Zootoca vivipara) inhabiting multiple biogeographic regions

2018

[Aim]: During glaciations, the distribution of temperate species inhabiting the Northern Hemisphere generally contracts into southern refugia; and in boreo‐alpine species of the Northern Hemisphere, expansion from Northern refugia is the general rule. Little is known about the drivers explaining vast distributions of species inhabiting multiple biogeographic regions (major biogeographic regions defined by the European Environmental Agency). Here we investigate the fine‐scale phylogeography and evolutionary history of the Eurasian common lizard (Zootoca vivipara), the terrestrial reptile with the world's widest and highest latitudinal distribution, that inhabits multiple biogeographic region…

Increased survival of honeybees in the laboratory after simultaneous exposure to low doses of pesticides and bacteria

2018

Recent studies of honeybees and bumblebees have examined combinatory effects of different stressors, as insect pollinators are naturally exposed to multiple stressors. At the same time the potential influences of simultaneously occurring agricultural agents on insect pollinator health remain largely unknown. Due to different farming methods, and the drift of applied agents and manure, pollinators are most probably exposed to insecticides but also bacteria from organic fertilizers at the same time. We orally exposed honeybee workers to sub-lethal doses of the insecticide thiacloprid and two strains of the bacterium Enterococcus faecalis, which can occur in manure from farming animals. Our re…

Polar Bear in 'Fortitude'. Affective Aesthetics and Politics of Climate Change

2021

In the first season of the television Eco Noir crime series “Fortitude” (2015) the polar bear appears as a sticky object that embodies an ambiguous affective charge as an icon of global warming. This article discusses the ways in which the polar bear evokes viewer affect in the series through two discourses. The first one relates to violence, essentially present in crime narratives, and how the human and nonhuman animal are positioned in relation to global warming, violence and each other. It raises questions of place and belonging in a local and global context and examines how the polar bear is constructed in terms of stranger danger and victimization in relation to human animals and the t…

The relationship between stocking eggs in boreal spawning rivers and the abundance of brown trout parr

2015

Abstract Stocking with eggs has been widely used as a management measure to support degraded salmonid stocks. In Finland, Atlantic salmon and both sea-migrating and lake-migrating brown trout are stocked as eggs, alevins, fry, parr, and smolt, whereas trout are also stocked as mature fish. The aim of this stocking is to improve catches and to support collapsed spawning stocks. We assessed the success of stocking with brown trout eggs in a study of 17 Finnish boreal forest rivers, of which 9 were subject to egg stocking. All rivers contained some naturally spawning trout. In 16 rivers, including non-stocking years and unstocked rivers, egg stocking did not increase the total (wild and stocke…

Teaching Archaeological Heritage Management: Towards a Change in Paradigms

2018

The concept of archaeological heritage management (AHM) has been key to wider archaeological research and preservation agendas for some decades. Many universities and other education providers now offer what is best termed heritage management education (HME) in various forms. The emphasis is commonly on archaeological aspects of heritage in a broad sense and different terms are often interchangeable in practice. In an innovative working-conference held in Tampere, Finland, we initiated a debate on what the components of AHM as a course or curriculum should include. We brought together international specialists and discussed connected questions around policy, practice, research and teaching/…

Atlantic salmon survival at sea: temporal changes that lack regional synchrony

2022

Spatial and temporal synchrony in abundance or survival trends can be indicative of whether populations are affected by common environmental drivers. In Atlantic salmon (Salmo salar L.), return rates to natal rivers have generally been assumed to be affected primarily by shared oceanic conditions, leading to spatially synchronous trends in mortality. Here, we investigated the existence of parallel trends in salmon sea survival, using data on migrating smolts and returning adults from seven Canadian populations presumed to share feeding grounds. We analysed sea survival, using a Bayesian change-point model capable of detecting non-stationarity in time series data. Our results indicate that w…

Solar PAR and UVR modify the community composition and photosynthetic activity of sea ice algae

2015

The effects of increased photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) on species diversity, biomass and photosynthetic activity were studied in fast ice algal communities. The experimental set-up consisted of nine 1.44 m(2) squares with three treatments: untreated with natural snow cover (UNT), snow-free (PAR + UVR) and snow-free ice covered with a UV screen (PAR). The total algal biomass, dominated by diatoms and dinoflagellates, increased in all treatments during the experiment. However, the smaller biomass growth in the top 10-cm layer of the PAR + UVR treatment compared with the PAR treatment indicated the negative effect of UVR. Scrippsiella complex (mainly…

Elinaikamallit gerontologisessa tutkimuksessa : alkoholin käytön ja tupakoinnin vaikutus elinaikaan

1998

Interacting effects of simulated eutrophication, temperature increase, and microplastic exposure on Daphnia

2020

The effects of multiple stressors are difficult to separate in field studies, and their interactions may be hard to predict if studied in isolation. We studied the effects of decreasing food quality (increase in cyanobacteria from 5 to 95% simulating eutrophication), temperature increase (by 3 °C), and microplastic exposure (1% of the diet) on survival, size, reproduction, and fatty acid composition of the model freshwater cladoceran Daphnia magna. We found that food quality was the major driver of Daphnia responses. When the amount of cyanobacteria increased from 5 to 95% of the diet, there was a drastic decrease in Daphnia survival (from 81 ± 15% to 24 ± 21%), juvenile size (from 1.8 ± 0.…

Vulnerability of the North Water ecosystem to climate change

2021

High Arctic ecosystems and Indigenous livelihoods are tightly linked and exposed to climate change, yet assessing their sensitivity requires a long-term perspective. Here, we assess the vulnerability of the North Water polynya, a unique seaice ecosystem that sustains the world’s northernmost Inuit communities and several keystone Arctic species. We reconstruct mid-to-late Holocene changes in sea ice, marine primary production, and little auk colony dynamics through multi-proxy analysis of marine and lake sediment cores. Our results suggest a productive ecosystem by 4400–4200 cal yrs b2k coincident with the arrival of the first humans in Greenland. Climate forcing during the late Holocene, l…