Search results for "boreaalinen"
showing 8 items of 58 documents
Plant biodiversity in boreal wood-pastures : impacts of grazing and abandonment
2016
Microbial controls of greenhouse gas emissions from boreal lakes
2015
Feeding ecology and behaviour of pikeperch, Sander lucioperca (L.) in boreal lakes
2008
Kuhakannat ovat parin viime vuosikymmenen aikana vahvistuneet. Samalla myös tiedontarve kuhan perusekologiasta on kasvanut. FK Tapio Keskisen väitöskirjassa tutkittiin kuhan merkitystä järvien kalayhteisöissä. Erityisesti rehevissä järvissä kuha on tärkeä petokala.Telemetrialähettimellä merkittyjä kuhia seurattiin Päijänteen vesistössä. Osa kuhista oli paikallisia liikkuen vain parin kilometrin säteellä, kun taas osa vaelsi pisimmillään yli parikymmentä kilometriä. Kesäaikaan kuhat suosivat kahta erillistä elinympäristöä: virtaavia, lämpötilakerrostumattomia alueita ja lämpötilakerrostuneita selkävesiä. Kuhat hakeutuivat lämpimimpään tarjolla olevaan veteen vuorokaudenajasta riippumatta. Va…
Subtropical streams harbour higher genus richness and lower abundance of insects compared to boreal streams, but scale matters
2018
Aim: Biological diversity typically varies between climatically different regions, and regions closer to the equator often support higher numbers of taxa than those closer to the poles. However, these trends have been assessed for a few organism groups, and the existing studies have rarely been based on extensive identical surveys in different climatic regions. Location: We conducted standardized surveys of wadeable streams in a boreal (western Finland) and a subtropical (south-eastern Brazil) region, sampling insects identically from 100 streams in each region and measuring the same environmental variables in both regions. Taxon: Aquatic insects. Methods: Comparisons were made at the scale…
Eco-epidemiology of tick- and rodent-borne pathogens in boreal forests
2017
Infectious diseases are amongst the ten major causes of human mortality worldwide, 60% of them being animal-borne. Variations of abiotic and biotic conditions are likely to modify the transmission of parasites and pathogens within reservoir species, and, as a consequence, alter the zoonotic risk for human. My thesis aims at elucidating the dynamics and mechanisms of the maintenance of ticks, tick-borne pathogens (TBPs) and the Puumala hantavirus (PUUV) in the reservoir host, the bank vole (Myodes glareolus, BV). In Northern Europe, tick-borne diseases are growing in importance to human because of the latitudinal expansion of the tick Ixodes ricinus. Field monitoring revealed that I. ricinus…
Management diversification increases habitat availability for multiple biodiversity indicator species in production forests
2022
Context Forest biodiversity is closely linked to habitat heterogeneity, while forestry actions often cause habitat homogenization. Alternative approaches to even-aged management were developed to restore habitat heterogeneity at the stand level, but how their application could promote habitat diversity at landscape scale remains uncertain. Objectives We tested the potential benefit of diversifying management regimes to increase landscape-level heterogeneity. We hypothesize that different styles of forest management would create a diverse mosaic of forest habitats that would in turn benefit species with various habitat requirements. Methods Forest stands were simulated under business-as-usua…
Interpreting wind damage risk-how multifunctional forest management impacts standing timber at risk of wind felling
2022
AbstractLandscape multifunctionality, a widely accepted challenge for boreal forests, aims to simultaneously provide timber, non-timber ecosystem services, and shelter for biodiversity. However, multifunctionality requires the use of novel forest management regimes optimally combined over the landscape, and an increased share of sets asides. It remains unclear how this combination will shape stand vulnerability to wind disturbances and exposed timber volume. We combined forest growth simulations and multi-objective optimization to create alternative landscape level forest management scenarios. Management choices were restricted to 1) rotation forestry, 2) continuous cover forestry, and 3) a…