Terpenoids of the essential oil from Molopospermum peloponnesiacum roots

The investigation of the essential oil from Molopospermum peloponnesiacum roots afforded, in addition to some well known terpenoids, two aromatic aldehydes, which were found for the first time as volatile oil components. Their structures were elucidated by spectroscopic methods. The formation of these aldehydes during steam distillation from unstable precursors is discussed.     

Does off-trail backcountry skiing disturb moose?

The advancement of recreational activities into wildlife habitat calls for a better knowledge about the effects of human-induced disturbances, particularly in systems where humans dominate wildlife mortality. We exposed nine adult free-ranging female moose repeatedly to off-trail backcountry skiing to study moose behavior and habituation using a controlled field experiment in Northern Sweden. Moose response was short-term, but distinct. Moose moved 33-fold faster during the first hour following disturbance, resulting in almost a doubling of the energetic usage per kilogram body weight. Movement rates increased 3 h following disturbances, came along with enlarged activity ranges at the day of disturbance, and resulted in moose leaving the original area. We found no evidence for habituation. Because of the short-term response, the effect of single skiing disturbance events on the overall energy budget of large-bodied animals in good body condition is likely to be negligible. We recommend off-trail skiers to avoid following wildlife tracks because such disturbances bear risk for more severe consequences on wildlife's energy budget if wildlife resists habituation, if an animal's risk perception is high, or when the frequency of disturbance increases.     

Regeneration growth of the invasive clonal forb Rorippa austriaca (Brassicaceae) in relation to fertilization and interspecific competition

A special type of clonal growth, spread by lateral roots, ishypothesized to be a favourable trait of invasive, opportunistic plant speciesof disturbed habitats. We tested this hypothesis for the invasive forbRorippa austriaca (Brassicaceae). Regenerationfrom root fragments, subsequent vegetative spread and allocation patterns inrelation to varied nutrient supply and intensity and pattern of interspecificcompetition were analyzed in container experiments. Regeneration success fromroot fragments was 100% and clonal spread was rapid but vegetativeperformance was strongly reduced under unfertilized conditions and,particularly, when interspecific competition was present. While the ratio ofabove- to belowground bio-mass did not differ considerably betweentreatments, R. austriaca allocated a high amount ofresources to belowground growth resulting in low aboveground but highbelowground biomass at harvest time relative to the matrix vegetation.Differences in shoot number or biomass between simulated gaps and denselyvegetated quadrants in the containers were (relatively) weak.Reproductive effort was less reduced under low resource levels, and the clonesdid not set seed at all, irrespective of the treatment. Our results show thatclonal growth by lateral roots and plasticity in clonal growth patterns inR. austriaca promote both exploitation of gaps andnutrient-rich microsites and resistance to competitors. Such plasticity,combined with its ability to regenerate from widely-dispersed rootfragments, contribute to the ability of the species to invade and persistwithindisturbed and spatially heterogeneous habitats.