Hämähäkkieläimet : Arachnida

Impacts of elevated CO2 and temperature on the soil fauna of boreal forests

Abstract Responses of dominant soil decomposer animals in northern coniferous forests, enchytraeids and microarthropods, to elevated CO 2 concentration and temperature were studied by sampling an experiment consisting of closed field chambers with a ground area of 5.9 m 2 . Six species of enchytraieds were found in the study, with Cognettia sphagnetorum comprising 87% of all individuals. The treatments did not significantly affect the numbers of C. sphagnetorum . No treatment induced changes were found in oribatid mites, but numbers of acaridid mites were lowest in the chambers with elevated CO 2 concentration and in those with elevated temperature. The chambers had lower densities of actin…

The arthropod community of boreal Norway spruce forests responds variably to stump harvesting

Forest fuel harvesting increases the need to collect not just logging residues but also tree stumps from harvested stands. This biomass removal has raised concern over forest biodiversity. Here, the effects of stump harvesting on spiders, ants, harvestmen, ground beetles and epiedaphic springtails occupying boreal Norway spruce (Picea abies) forest floor were studied two and five years after harvesting by comparing pitfall trap samples from clear-cut sites with and without subsequent stump harvesting and from unharvested mature forests in central Finland. At harvested sites, traps were placed both on intact and exposed mineral soil surface. Open-habitat and generalist ground beetles benefit…