Abstract
Northern peatlands are very sensitive to changes in climate. Impacts of increased temperatures on hydrology, vegetation structure and soil carbon are already well documented from northern peatlands. In contrast, effects of global warming on soil mites, and seasonal effects in particular, have received less attention, even though soil mites are an important component in ecosystems as they contribute to nutrient dynamics and decomposition. We investigated the impacts of long-term (16 years) experimental seasonal climate manipulations (summer warming, winter warming with snow accumulation, and year-round warming) on oribatid (Oribatida) and mesostigmatid (Mesostigmata) mite communities in a peat bog underlain by discontinuous permafrost, in Abisko, Northern Sweden. We found that (1) Year-round warming treatment had neither impact on life-history trait compositions nor on total abundances of oribatid mites, possibly because of opposite effects of summer and winter warming; (2) Small-bodied oribatid mites, in particular those belonging to genera Suctobelba, increased in abundance under the summer warming treatment; (3) The species richness of oribatid mites was negative affected by year-round warming; (4) Mesostigmatid mites, which were not identified to species level, were found to decrease in abundance under year-round warming. Because different mite taxa with different body sizes and diets play distinct roles in carbon and nutrient dynamics, the observed changes in mite communities may impact ecosystem functions in northern peatlands.
Highlights
Global mean temperatures have increased during the twentieth century and still continue to do so
Mean densities of oribatid genus Suctobelba were 65% higher in summer warming treatment plots compared to control (Tukey-Kramer post hoc test, p = 0.028) and 70% higher compared to winter warming with snow accumulation treatments (Tukey-Kramer post hoc test, p = 0.015; Table 3)
The effects of seasonal climate manipulations on oribatid mite communities In Arctic and sub-Arctic ecosystems, seasonality of climate warming effects may be important for soil-dwelling organisms, which have to cope with annual cycles of great environmental variability from season to season
Summary
Global mean temperatures have increased during the twentieth century and still continue to do so. The past decade has seen a shift from a merely taxonomic approach to assessment of ecological and life-history traits of invertebrates in response to environmental change. Functional, ecological and life-history traits are thought to be sensitive indicators of community change, and can reveal mechanisms behind the response of species to environmental manipulations The approach is increasingly used to explain the responses of microinvertebrates to environmental change, for example, the responses of Collembola to simulated warming in the sub-Arctic (Makkonen et al 2011), the impacts of natural disturbance and management intensity on forest microarthropods (Farska et al 2014a, b) and effects of climate change on microarthropod communities in boreal forests (Lindo et al 2012)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
