Modeling the effects of climate change and management on the dead wood dynamics in boreal forest plantations

The present research examines the joint effects of climate change and management on the dead wood dynamics of the main tree species of the Finnish boreal forests via a forest ecosystem simulator. Tree processes are analyzed in stands subject to multiple biotic and abiotic environmental factors. A special focus is on the implications for biodiversity conservation thereof. Our results predict that in boreal forests, climate change will speed up tree growth and accumulation ending up in a higher stock of dead wood available as habitat for forest-dwelling species, but the accumulation processes will be much smaller in the working landscape than in set-asides. Increased decomposition rates driven by climate change for silver birch and Norway spruce will likely reduce the time the dead wood stock is available for dead wood-associated species. While for silver birch, the decomposition rate will be further increased in set-aside in relation to stands under ordinary management, for Norway spruce, set-asides can counterbalance the enhanced decomposition rate due to climate change thereby permitting a longer persistence of different decay stages of dead wood.     

No Effect of Social Competition on Sham Dustbathing in Furnished Cages for Laying Hens

The wire-mesh netting used as the floor material in cages is often claimed to cause walking problems for foxes. The validity of this claim was tested in 96 15-year-old secondary school pupils. They were shown five separate 2 min fragments of videotapes showing the cage pairs with randomized floor material (solid or wire mesh) but with an obstructed view of the floor. The pupils were asked to evaluate the flooring material based on what they actually saw. The mean proportion of correct answers out of 5 for individuals were slightly more than half correct (0.54), but this did not differ significantly from the random value (0.5). When the pairs of foxes had different flooring material, the pupils answered correctly (0.58, P <0.05). Thus, the pupils were not able to identify a specific floor type (wire-mesh or solid floor) but were able to differentiate between two different types of floor based solely on the behaviour of the foxes.     

The Origin of Amniotic Polymorphonuclear Leucocytes in the Mare

The objective of this study was to investigate the presence and origin of polymorphonuclear leucocytes (PMNLs) in the amniotic fluid of mares giving birth to healthy foals. Material from 25 mares was included. Amniotic fluid was collected during parturition before breakage of the amniotic vesicle. Manual microscopic cytologic evaluation was made on cytospin preparations after staining. PMNLs were found in all amniotic samples examined. The genomic DNA was extracted from 12 of the amniotic fluid samples and was genotyped. The results indicate that the PMNLs originate from the foetus.     

Waves of larch budmoth outbreaks in the European alps

Spatially extended population models predict complex spatiotemporal patterns, such as spiral waves and spatial chaos, as a result of the reaction-diffusion dynamics that arise from trophic interactions. However, examples of such patterns in ecological systems are scarce. We develop a quantitative technique to demonstrate the existence of waves in Central European larch budmoth (Zeiraphera diniana Gn.) outbreaks. We show that these waves travel toward the northeast-east at 210 kilometers per year. A theoretical model involving a moth-enemy interaction predicts directional waves, but only if dispersal is directionally biased or habitat productivity varies across the landscape. Our study confirms that nonlinear ecological interactions can lead to complex spatial dynamics at a regional scale.