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Using the long-tailed tit (Aegithalos c. caudatus) as an example of the so-called irruptive species, the ecophysiological characteristics (body mass, fat reserves) and migration
speed during autumn period were analyzed. The mean body mass and the median fat score did not depend on the number of migrating
individuals. There was no evidence of the so-called stress in birds, participating in migration: migrants had even higher
fat reserves than residents, while no significant difference in the body mass was recorded. The increase in fat reserves in
the long-tailed tit during migration period was similar to the seasonal changes in energy reserves known for typical migrants.
This makes it possible for late-migrating individuals to maintain higher total speed of migration compared to early-migrating
ones. Basing on the obtained data, we conclude that the ecophysiological characteristics of the long-tailed tits migrating
in autumn are similar to those of regular migrants. 相似文献
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James D. MacNeil Mitsuru Hikichi 《Journal of environmental science and health. Part. B》2013,48(5):375-385
Abstract Two cover sprays of phosmet were applied to an orchard adjoining a camping area and a bird sanctuary with a resident goose population. Insecticide residues were monitored on orchard leaves, orchard ground cover, ground cover in the camp‐site and along the adjacent lakeshore. Despite attempts to minimize drift, significant spray residues were found outside the target area. Residues on ground cover and leaves were reduced by sprinkler irrigation subsequent to spray application. 相似文献
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M. S. Christin L. Ménard I. Giroux D. J. Marcogliese S. Ruby D. Cyr M. Fournier P. Brousseau 《Environmental science and pollution research international》2013,20(2):601-611
There is evidence that over the last 30 years, there have been mass declines in diverse geographic locations among amphibian populations due to disease outbreaks. Multiple causes have been suggested to explain this increase in disease incidence. Among these, climate changes, environmental pollution and reduced water quality are gaining attention. Indeed, some chemicals of environmental concerns are known to alter the immune system. It is possible that exposure to these pollutants could alter the immune system of anurans and render them more susceptible to different pathogens. In this study, we sampled Rana pipiens in five different sites near St. Lawrence River (Quebec, Canada) during the months of July and September in 2001. Two of these sites were protected areas, in which low levels of pesticides were detected, while the remaining three sites were located in areas with intensive corn and soybeans cultivations. Our results demonstrated that frogs living in agricultural regions are smaller in size and weight than frogs living in areas with lower levels of pesticides at both sampling times. Moreover, we have observed a significant decrease in the number of splenocytes (cellularity) and the phagocytic activity in frogs sampled in impacted sites. Taken together, these results suggest that frogs living in agricultural regions might be more vulnerable to infections and diseases through their smaller size and alteration of their immune system. Our results also contribute to the overall discussion on factors involved in amphibian declines. 相似文献
396.
PAH air pollution at a Portuguese urban area: carcinogenic risks and sources identification 总被引:1,自引:1,他引:0
K. Slezakova J. C. M. Pires D. Castro M. C. M. Alvim-Ferraz C. Delerue-Matos S. Morais M. C. Pereira 《Environmental science and pollution research international》2013,20(6):3932-3945
This study aimed to characterize air pollution and the associated carcinogenic risks of polycyclic aromatic hydrocarbon (PAHs) at an urban site, to identify possible emission sources of PAHs using several statistical methodologies, and to analyze the influence of other air pollutants and meteorological variables on PAH concentrations.The air quality and meteorological data were collected in Oporto, the second largest city of Portugal. Eighteen PAHs (the 16 PAHs considered by United States Environment Protection Agency (USEPA) as priority pollutants, dibenzo[a,l]pyrene, and benzo[j]fluoranthene) were collected daily for 24 h in air (gas phase and in particles) during 40 consecutive days in November and December 2008 by constant low-flow samplers and using polytetrafluoroethylene (PTFE) membrane filters for particulate (PM10 and PM2.5 bound) PAHs and pre-cleaned polyurethane foam plugs for gaseous compounds. The other monitored air pollutants were SO2, PM10, NO2, CO, and O3; the meteorological variables were temperature, relative humidity, wind speed, total precipitation, and solar radiation. Benzo[a]pyrene reached a mean concentration of 2.02 ng?m?3, surpassing the EU annual limit value. The target carcinogenic risks were equal than the health-based guideline level set by USEPA (10?6) at the studied site, with the cancer risks of eight PAHs reaching senior levels of 9.98?×?10?7 in PM10 and 1.06?×?10?6 in air. The applied statistical methods, correlation matrix, cluster analysis, and principal component analysis, were in agreement in the grouping of the PAHs. The groups were formed according to their chemical structure (number of rings), phase distribution, and emission sources. PAH diagnostic ratios were also calculated to evaluate the main emission sources. Diesel vehicular emissions were the major source of PAHs at the studied site. Besides that source, emissions from residential heating and oil refinery were identified to contribute to PAH levels at the respective area. Additionally, principal component regression indicated that SO2, NO2, PM10, CO, and solar radiation had positive correlation with PAHs concentrations, while O3, temperature, relative humidity, and wind speed were negatively correlated. 相似文献
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