Climate-driven changes in air quality over Europe by the end of the 21st century,with special reference to Portugal

Climate change alone may deeply impact air quality levels in the atmosphere because the changes in the meteorological conditions will induce changes on the transport, dispersion and transformation of air pollutants. The aim of this work was to evaluate the impact of climate change on the air quality over Europe and Portugal, using a reference year (year 1990) and a IPCC SRES A2 year (year 2100). The Hadley Centre global atmospheric circulation model (HadAM3P) was used to provide results for these two climatic scenarios, which were then used as synoptic forcing for the MM5-CHIMERE air quality modelling system. In order to assess the contribution of future climate change on O₃ and PM concentrations, no changes in regional emissions were assumed and only climate change forcing was considered. The modelling results suggest that the O₃ monthly mean levels in the atmosphere may increase almost 50 μg m^?3 across Europe in July under the IPCC SRES A2 scenario. In Portugal, this increase may reach 20 μg m^?3. The changes of PM10 monthly average values over Europe will depend on the region. The increase in PM10 concentrations during specific months could be explained by the average reduction of the boundary layer height and wind speed.     

An energy–distance trade-off in a central-place forager,the Antarctic fur seal (<Emphasis Type="Italic">Arctocephalus gazella</Emphasis>)

We tested the prediction that lactating fur seals (Arctocephalus gazella) at South Georgia will take prey of greater energy density with increasing distance of foraging from the colony. The study investigated the differences in diet of fur seals foraging within two regions, one near the breeding colony and the other at greater distance. Diet varied significantly in relation to foraging location. Dietary items of low quality were eaten in both regions but more food items with a high-energy content appeared in the diet of seals travelling to distant oceanic waters. We conclude that there is likely to be a trade-off between energy gain and distance travelled which enables female fur seals to maintain a relatively constant rate of energy delivery to their offspring irrespective of the distance travelled to find food.     

Traffic noise, work noise and cardiovascular risk factors: The Caerphilly and Speedwell collaborative heart disease studies

As part of two large heart surveys, associations between traffic noise exposure and cardiovascular risk factors were studied. The Caerphilly sample (small town, total sample) consisted of 2512 men aged 45 to 59 years and the Speedwell sample (suburb of a major city, random sample) of 2030 men of same age group. Both studies have a prospective design; cross-sectional results are presented here. Acoustic measurements were carried out in both areas. Among the possible risk factors for ischaemic heart disease studied were blood pressure, blood coagulation, blood lipids and other biochemical factors. Statistically significant noise effects were detected for systolic blood pressure, total cholesterol, HDL cholesterol, total triglycerides, blood viscosity, platelet count and glucose level, although not all of these were consistent with noise being a risk factor for heart disease. In a subsample, the additional influence of work noise as determined by noise dosimetry was studied in 255 men, taking the use of ear protection into account. The associations between traffic noise and risk factors were more pronounced in men who also were exposed to high work noise levels.     

Does the effect of low temperature on osmoregulation by the prawn Palaemon elegans Rathke, 1837 explain winter migration offshore?

Osmoregulation by the European glass prawn Palaemon elegans Rathke, 1837 was impaired at low temperature (2°C) and high salinities (full strength sea water 35 PSU). Under these conditions, small individuals showed stronger osmoregulatory ability than larger individuals. This observation could partially explain differences in winter migrations off the UK coast where mainly large P. elegans go offshore, leaving smaller individuals in high shore rock pools, a finding consistent with winter experiments in situ.     

Distribution of radionuclides among the main components of Lake Chervyanoe in the Eastern Ural Radioactive Trace

Radioecological conditions have been estimated in Lake Chervyanoe located on the central axis of the Eastern Ural Radioactive Trace (EURT) about 100–110 km northeast of the Mayak Production Association. Data on the ⁹⁰Sr and ¹³⁷Cs contents in the main components of the lake, the distribution of these radionuclides over the profile of bottom sediments, and their amounts in the lake are presented. The experimental data have been used to construct mathematical models for estimating changes in the radionuclide concentrations and amounts in the water and bottom sediments of the lake over a long period after the nuclear accident, as well as the tritium content of the lake water in different periods of time.     

Clean catalytic technology for liquid phase hydrocarbon oxidation

 Liquid phase hydrocarbon oxidation is one of the principal routes towards industrial organic chemicals. However, low product selectivity and associated by-product formation are major problems in several oxidation processes. As a result of the increasingly stringent environmental regulations, the development of oxidation catalysts has been a major challenge in the last decade. An overview of novel selective and clean oxidation catalysts and processes is presented. Received: 27 July 1998 / Accepted: 8 September 1998