Selection effects of air pollution on gene pools of Norway spruce, European silver fir and European beech.

The effects of industrial pollution on allelic and genotypic structures of Norway spruce. European silver fir and European beech were investigated by means of isozyme analysis. In a mixed Norway spruce-silver fir forest stand in an area heavily polluted by sulphur dioxide and heavy metals in the region of Spis (eastern Slovakia), pairs of neighbouring damaged and apparently healthy trees were selected in two replicates (44 and 69 pairs in a heavily and moderately damaged stand, respectively). Pairwise sampling of trees with contrasting vitality was applied to reduce potential effects of site heterogeneity on the vitality of sampled trees. No significant differences in allelic and genotypic frequencies were found between sets of healthy and declining trees. There were differences in the single-locus heterozygosities, but these were not consistent between the replicates. However, the set of damaged trees exhibited higher levels of genetic multiplicity and diversity, possibly due to the deleterious effect of rare alleles under the conditions of air pollution. Consequently. following the decline of pollutant-sensitive trees, the remaining stand will be depleted of a part of alleles with unknown adaptive value to future selection pressures.     

The natives are restless, but not often and mostly when disturbed

The argument that the threat posed by introduced species is overblown is often buttressed by the observation that native species sometimes also become invasive. An examination of the literature on plant invasions in the United States shows that six times more nonnative species have been termed invasive than native species, and that a member of the naturalized nonnative pool is 40 times more likely than a native species to be perceived as invasive. In the great majority of instances in which a native plant species is seen as invasive, the invasion is associated with an anthropogenic disturbance, especially changed fire or hydrological regime, livestock grazing, and changes wrought by an introduced species. These results suggest that natives are significantly less likely than nonnatives to be problematic for local ecosystems.     

Collocated comparisons of continuous and filter-based PM2.5 measurements at Fort McMurray,Alberta, Canada

Collocated comparisons for three PM_2.5 monitors were conducted from June 2011 to May 2013 at an air monitoring station in the residential area of Fort McMurray, Alberta, Canada, a city located in the Athabasca Oil Sands Region. Extremely cold winters (down to approximately ?40°C) coupled with low PM_2.5 concentrations present a challenge for continuous measurements. Both the tapered element oscillating microbalance (TEOM), operated at 40°C (i.e., TEOM₄₀), and Synchronized Hybrid Ambient Real-time Particulate (SHARP, a Federal Equivalent Method [FEM]), were compared with a Partisol PM_2.5 U.S. Federal Reference Method (FRM) sampler. While hourly TEOM₄₀ PM_2.5 were consistently ~20–50% lower than that of SHARP, no statistically significant differences were found between the 24-hr averages for FRM and SHARP. Orthogonal regression (OR) equations derived from FRM and TEOM₄₀ were used to adjust the TEOM₄₀ (i.e., TEOM_adj) and improve its agreement with FRM, particularly for the cold season. The 12-year-long hourly TEOM_adj measurements from 1999 to 2011 based on the OR equations between SHARP and TEOM₄₀ were derived from the 2-year (2011–2013) collocated measurements. The trend analysis combining both TEOM_adj and SHARP measurements showed a statistically significant decrease in PM_2.5 concentrations with a seasonal slope of ?0.15 μg m^?3 yr^?1 from 1999 to 2014.Implications: Consistency in PM_2.5 measurements are needed for trend analysis. Collocated comparison among the three PM_2.5 monitors demonstrated the difference between FRM and TEOM, as well as between SHARP and TEOM. The orthogonal regressions equations can be applied to correct historical TEOM data to examine long-term trends within the network.     

Sexual conflict over fertilizations: female bluethroats escape male paternity guards

Extra-pair copulations create a potential for sexual conflict in pair-bonding birds. Here we report an experimental study of the bluethroat, Luscinia s. svecica, in which the throat ornament of males was blackened with Nyanzol D in order to reduce their sexual attractiveness and thus increase the sexual conflict over fertilizations. In an earlier study, we showed that males blackened before pairing had a lower success in attracting social mates than controls, whereas males blackened after pairing guarded their mates more intensely and sang less than controls. Here we add behavioural data from one more year on males blackened after pairing and corroborate our previous finding that the manipulation caused males to guard their mates more intensely and advertise less for additional mates. Blackened males did not suffer more intrusions from neighbouring males than did controls. Paternity analyses of the combined data set, using multilocus DNA fingerprinting and microsatellite typing, revealed that blackened males lost significantly more paternity than controls. There was also a tendency for blackened males to show a lower success in achieving extra-pair fertilizations. These results indicate that females have the upper hand in the sexual conflict over fertilizations, as females paired with unattractive males can achieve more extra-pair paternity despite the greater constraint posed by the intensified mate guarding. Still, within the blackened group, there were some indications that males guarding more intensely and singing less had higher paternity than males guarding less and singing more, suggesting a marginal positive effect of guarding for unattractive males. Male mate guarding must nevertheless be considered a best-of-a-bad-job strategy in this species. Received: 4 December 1997 / Accepted after revision: 14 June 1998     

The chemical industry's commitment to continuous improvement in environmental performance

One of the greatest challenges facing the chemical industry today is regaining the lost confidence of the public. This concern led to the Chemical Manufacturers Association's (CMA's) adoption of the Responsible Care® initiative—not a slick new promotional campaign but a commitment to continuous improvement in environmental performance. The author highlights components of the program, which is seen as an outgrowth of Total Quality Management.     

A comparison of meal size and feeding rate of the lysianassid amphipods Anonyx nugax,Onisimus (=Pseudalibrotus) litoralis and Orchomenella pinguis

Lysianassid amphipods were collected in 1987 from Frobisher Bay, Baffin Island, and from the Mingan Archipelago, Gulf of St Lawrence. Meal size and feeding rate of Anonyx nugax (Phipps), Onisimus (=Pseudalibrotus) litoralis (Krøyer) and Orchomenella pinguis (Boeck) were estimated directly, gravimetrically and/or from predictive equations. Size-specific ingestion was greatest in A. nugax, which fed swiftly and efficiently in comparison to O. litoralis and O. pinguis. These two latter species dispersed some bait while feeding and crawling on its surface. Groups of lysianassids fed more wastefully than single individuals. Meal size of females of O. litoralis decreased with increasing maturity, while berried females of O. pinguis consumed less food than mature males. Up to 30 d of starvation had no effect on survival and feeding ability of A. nugax, but 10 to 15 d of starvation dramatically reduced feeding ability or killed O. litoralis and O. pinguis. Differences between meal size, feeding rate and survival point to divergent feeding patterns, which also have been evidenced elsewhere by analysis of gut contents. O. litoralis and O. pinguis are best characterized as facultative scavengers, while large A. nugax are possibly obligate carnivores. Results emphasize the importance of lysianassid amphipods, particularly A. nugax, as bait stealers and as predators of commercial species trapped by various fishing gear.     

Growth responses of Populus tremuloides clones to interacting elevated carbon dioxide and tropospheric ozone.

The Intergovernmental Panel of Climate Change (IPCC) has concluded that the greenhouse gases carbon dioxide (CO2) and tropospheric ozone (O3) are increasing concomitantly globally. Little is known about the effect of these interacting gases on growth, survival, and productivity of forest ecosystems. In this study we assess the effects of three successive years of exposure to combinations of elevated CO2 and O3 on growth responses in a five trembling aspen (Populus tremuloides) clonal mixture in a regenerating stand. The experiment is located in Rhinelander, Wisconsin, USA (45 degrees N 89 degrees W) and employs free air carbon dioxide and ozone enrichment (FACE) technology. The aspen stand was exposed to a factorial combination of four treatments consisting of elevated CO2 (560 ppm), elevated O3 (episodic exposure-90 microl l(-1) hour(-1)), a combination of elevated CO2 and O3, and ambient control in 30 m treatment rings with three replications. Our overall results showed that our three growth parameters including height, diameter and volume were increased by elevated CO2, decreased by elevated O3, and were not significantly different from the ambient control under elevated CO2 + O3. However, there were significant clonal differences in the responses; all five clones exhibited increased growth with elevated CO2, one clone showed an increase with elevated O3, and two clones showed an increase over the control with elevated CO2 + O3, two clones showed a decrease, and one was not significantly different from the control. Notably. there was a significant increase in current terminal shoot dieback with elevated CO2 during the 1999-2000 dormant season. Dieback was especially prominent in two of the five clones, and was attributed to those clones growing longer into the autumnal season where they were subject to frost. Our results show that elevated O3 negates expected positive growth effects of elevated CO2 in Populus tremuloides in the field, and suggest that future climate model predictions should take into account the offsetting effects of elevated O3 on CO2 enrichment when estimating future growth of trembling aspen stands.     

Social learning and sustainable communities: An interim assessment of research into sustainable communities projects in the UK

Abstract

The delivery of many of the most pressing environmental issues will rely on changes in environmental attitudes and behaviour at community level. At a UN Special Session in 1997, the British Government highlighted its initiatives on Local Agenda 21 (LA21) and Going for Green (GFG) as significant advances. This paper adds a new perspective, drawing on the range of experiences of some of the research teams that have been working with local authorities on pilot Sustainable Community Projects (SCPs) in England and Scotland. It sheds light on three substantive themes: the tensions inherent in the implementation of internationally and nationally agreed goals through local action; the ambiguity of local agencies acting as facilitators of community ownership of processes, and the requirements for successful partnership between local authorities and higher education.