溴鼠灵对美洲红隼（Falco sparverius）的毒性及后续抗凝灭鼠剂暴露增加危害性的证据

生态毒理学中的一个重要问题是污染物暴露对生理功能和健康的长期影响程度。已有系列研究探讨了美国红隼摄入第二代抗凝血灭鼠剂（AR）溴鼠灵（BROD）的环境浓度。以0.3、1.0或3.0 μg BROD/g（wt）喂养7天后,红隼表现出剂量依赖性出血、组织病理学损伤和凝血病变（凝血酶原延长和罗素毒液组）。在终止为期7天的0.5 μg BROD/g饮食的暴露后,延长的凝血时间在一周内恢复到基线值,但肝和肾中的BROD残留（最终半衰期估计值>50天）在28天的恢复期内持续存在。为了检测连续性AR暴露的危险性,红隼连续暴露于第一代AR—氯鸟嘌呤（CPN;每日饮食1.5 μg/g）或第二代AR—BROD（每日饮食0.5 μg/g）中7天,在恢复期后,用低剂量CPN（每日饮食0.75 μg/g）暴露7天。与对照组和CPN处理组的红隼相比,后续暴露明显延长了BROD处理组的凝血酶原时间。这些数据表明,第二代AR—BROD可能具有长期影响,增加了随后AR暴露的毒性。自由放养的捕食性和食腐性野生动物经常反复暴露于AR中,在进行危害和风险评估时需要考虑到这种长期的毒理学效应。     

Ambrosia artemisiifolia in an Anthropogenic Landscape of Gomel Polesye

Russian Journal of Ecology -     

The Outcome of Northern Fur Seal Harvesting: The Results of Calibration of Mathematical Models Based on Observation Data (the Example of Tyulenii Island Population)

Tendencies in the dynamics of harvested northern fur seal (Callorhinus ursinus) population on the Tyulenii Island have been analyzed in detail. The results show that retardation of reproduction (decrease in the numbers of pups) and decline in the survival of young females (up to 3 years of age) by the late 1980s resulted in a reduction of the total number of females and a significant increase in the proportion of older females. This tendency changed during the later observation period (after 1988–1989) due to increase in the survival of young females: the female population has gradually recovered, with the proportion of young females increasing at the expense of old females (aged over 10 years). The age composition of males has also changed: the proportion of young animals has decreased, while that of large mature males (bulls) has increased. Moreover, the number of bulls continues to increase and has already exceeded the level that formerly provided for the well-being of the population. This, a paradoxical situation has arisen: the numbers of females and bulls are increasing, whereas pup production remains at a low level.

     

The Effect of Vaccinium vitis-idaea on Properties of Mountain-Meadow Soil under Alpine Lichen Heath

Russian Journal of Ecology - Abstract—The study of the effect of mycorrhiza symbiosis on the transformation of carbon and nitrogen compounds in soils is important in view of the necessity to...     

The Ratio between Chronographic and Geographic Variation in the Morphofunctional Features of Bank Vole (Clethrionomys glareolus Shreb.) in the South of Its Range

Russian Journal of Ecology - A simultaneous analysis of the chronographic variation of the mandible of bank vole (Clethrionomys glareolus Shreb.) in three longitudinally distant populations that...     

Modelling local and synoptic scale influences on ozone concentrations in a topographically complex region of Southern Italy

A modelling study with the on-line coupled Eulerian chemical-weather model WRF/Chem for the Southern Italian region around Cosenza (Calabria) was conducted to identify the influences of synoptic scale meteorology, local scale wind systems and local emissions on ozone concentrations in this orographically complex region. Four periods of 5–7 days were chosen, one from each season, which had wind pattern characteristics representative of typical local climatological conditions, in order to study the local versus non-local impacts on ozone transport and formation. To account for the complex terrain, the horizontal resolution of the smallest modelling domain was 3 km. Model results were compared with measurements to demonstrate the capability of the model to reproduce ozone concentrations in the region. The comparison was favourable with a mean bias of ?1.1 ppb. The importance of local emissions on ozone formation and destruction was identified with the use of three different emission scenarios. Generally the influence of regional emissions on the average ozone concentration was small. However during periods when mountain-sea wind systems were well developed and synoptic scale winds were weak, the influence of local emissions from the urban area was at its greatest. The maximum influence of local emissions on ozone concentrations was 18 ppb.     

Educating the next generation of atmospheric scientists within a European Network of Excellence

In order to promote the next generation of atmospheric scientists, the task Training and Education (T&E) in ACCENT, the European Network of Excellence in Atmospheric Composition Change (www.accent-network.org) has developed and implemented an Integrated Learning Environment (ILE). For school teachers and their students, the Internet-based “Global Change Magazine” provides up-to-date and freely accessible scientific material in English and five other languages. Additionally, T&E has produced online teaching material for early-career scientists. These e-learning modules are now being used in University Master's courses across Europe. T&E also organised training events for early-career scientists, combining scientific content with development in transferable skills, to focus on interdisciplinary collaboration, interaction with senior scientists, communication with stakeholders, and dissemination to the general public. Evaluation based on participant feedback evidences the effectiveness of these events, e.g., in terms of motivation to remain in the field. Methodologies and materials from T&E are being published in a Handbook on Best Practice, intended for both educators and scientists around the globe who are involved in education in the field of air quality and climate change science.     

Investigation of the positive artifact formation during sampling semi-volatile aerosol using wet denuders

Wet denuders are used in several steam-based semi-continuous aerosol monitors to avoid gaseous absorption artifacts and pre-humidify the air stream, while simultaneously allowing measurements of water-soluble gaseous species. Unlike dry denuders, wet denuders saturate the sample air stream with water vapor, which can lead to re-partitioning of water-soluble volatile species to the aerosol phase, thereby causing a positive artifact in aerosol measurements. This paper investigates the magnitude of the positive artifact formation occurring in wet denuders using modeling techniques. Gaseous nitric acid was used as an example of volatile water-soluble gas in both flat and annular wet denuders. We have also verified the occurrence of the positive artifact in a flat wet denuder through a laboratory experiment. The model results indicate that the magnitude of the artifact is rather limited under typical conditions being less than 2.5% of ambient nitric acid concentration for the flat denuder and less than 0.6% for the annular denuder. The magnitude of the artifact increases with condensational sink of the aerosol (i.e. with the mean aerosol size and number concentration) and aerosol water solubility. While the artifact is relatively small in the absolute sense, it could be substantial for aerosol nitrate measurements, especially in ammonia limited conditions, when the concentration of the nitric acid is high and the concentration of nitrate is low. Therefore, we recommend that the artifact is assessed regularly by replacing the wet denuder with a dry denuder.     

Wintertime size distribution of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the urban environment: Street- vs rooftop-level measurements

The size distribution of ambient air particles and associated organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) including hexachlorocyclohexanes (HCHs), DDT and metabolites, etc., was investigated at a traffic-impacted site of Thessaloniki, Greece. Investigation took place during wintertime of 2006 at two heights above ground: at the street level (1.5 m) and at the rooftop level (15 m). Size-resolved samples (<0.95 μm, 0.95–1.5 μm, 1.5–3 μm, 3–7.5 μm and >7.5 μm) were concurrently collected from the two height levels using five-stage high volume cascade impactors. At both heights, particle mass exhibited bimodal distribution with peaks in the 0.95–1.5 μm and the 3–7.5 μm size fractions, whereas most organic pollutants exhibited one peak at 0.95–1.5 μm. Apart from the 0.95–1.5 μm fraction, particle concentrations of all size ranges were significantly higher at the street level than at the rooftop as a result of more intensive vehicular emissions and road dust resuspension. On the contrary, the concentrations of most organic pollutants did not differentiate significantly between the two elevations.     

The stable isotope signature of methane emitted from plant material under UV irradiation

Recent experiments have shown that dry and fresh leaves, other plant matter, as well as several structural plant components, emit methane upon irradiation with UV light. Here we present the source isotope signatures of the methane emitted from a range of dry natural plant leaves and structural compounds. UV-induced methane from organic matter is strongly depleted in both ¹³C and D compared to the bulk biomass. The isotopic content of plant methoxyl groups, which have been identified as important precursors of aerobic methane formation in plants, falls roughly halfway between the bulk and CH₄ isotopic composition. C3 and C4/CAM plants show the well-established isotope difference in bulk ¹³C content. Our results show that they also emit CH₄ with different δ¹³C value. Furthermore, δ¹³C of methoxyl groups in the plant material, and ester methoxyl groups only, show a similar difference between C3 and C4/CAM plants. The correlation between the δ¹³C of emitted CH₄ and methoxyl groups implies that methoxyl groups are not the only source substrate of CH₄.Interestingly, δD values of the emitted CH₄ are also found to be different for C3 and C4 plants, although there is no significant difference in the bulk material. Bulk δD analyses may be compromised by a large reservoir of exchangeable hydrogen, but no significant δD difference is found either for the methoxyl groups, which do not contain exchangeable hydrogen. The δD difference in CH₄ between C3 and C4 plants indicates that at least two different reservoirs are involved in CH₄ emission. One of them is the OCH₃ group, the other one must be significantly depleted, and contribute more to the emissions of C3 plants compared to C4 plants. In qualitative agreement with this hypothesis, CH₄ emission rates are higher for C3 plants than for C4 plants.