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911.
The link between ecology and economies is manifest over the world as a result of long-term processes. But because these processes are long term, it is hard to prove the link. On Sardinia serious economic development was late to arrive, having occurred only over the last few decades. As a case study, research was carried out for 10 years on the state of nature as well as the economic growth in one of the least developed areas abutting the Gulf of Orosei on the east coast. Based on research and lasting attention to political affairs concerning the project, we formulate general recommendations for the area. In 1995, the Italian Government will be asked by the European Government to undertake serious steps to save endemics (especially herpetofauna) of Europe's last pristine areas. 相似文献
912.
Comparative overview of indoor air quality in Antwerp, Belgium 总被引:2,自引:0,他引:2
This comprehensive study, a first in Belgium, aimed at characterizing the residential and school indoor air quality of subgroups that took part in the European Community Respiratory Health Survey and the International Study of Asthma and Allergy in Childhood [Masoli M, Fabian D, Holt S, Beasley R. Global Burden of Asthma, Medical Research Institute of New Zealand, University of Southampton; 2004.] questionnaire-based asthma and related illnesses studies. The principal aim was to perform a base-line study to assess the indoor air quality in Antwerp in terms of various gaseous and particulate pollutants. Secondly, it aimed to establish correlations between these pollutants investigated, the pollutant levels in the indoor and outdoor micro-environments, findings of the previous questionnaire-based studies and an epidemiological study which ran in conjunction with this study. Lastly, these results were compared and evaluated with current indoor and ambient guidelines in various countries This paper presents selected results on PM1, PM2.5 and PM10 mass concentrations and elemental C estimates as black smoke, as well as gaseous NO(2), SO(2), O(3) and BTEX concentrations of 18 residences and 27 schools. These are related to current guidelines of Flanders, Germany, Norway, China and Canada and evaluated with reference to selected similar studies. It was found that indoor sources such as tobacco smoking and carpets, the latter causing re-suspension of dust, are responsible for elevated indoor respirable particulate matter and place school children and residents at risk. Both PM2.5 and PM10 equalled or exceeded the current guidelines adopted by Flanders, noting that 12-h and 24-h PM2.5 were compared with an annual limit value. Indoor and ambient NO(2) concentrations in the school campaign were higher than the annual EU ambient norm. The other studied pollutant levels were below the current guidelines. 相似文献
913.
Hanneke J. M. Meijer Arike Gill Perry G. B. de Louw Lars W. Van Den Hoek Ostende Julian P. Hume Kenneth F. Rijsdijk 《Die Naturwissenschaften》2012,99(3):177-184
Since 2005, excavations at Mare aux Songes, Mauritius, have revealed the presence of a very rich, ∼4,200-year-old fossil bone
bed including dodo (Raphus cucullatus) bones and bone fragments. The recently excavated dodo assemblage comprises at least 17 individuals and is characterised
by the presence of small and fragile skeletal elements, a dominance of leg elements and an absence of juveniles. The hydrology
of the area suggests that dodos, like many other species, were probably lured to Mare aux Songes by the presence of freshwater
during times of drought. The most likely scenario for the origin of the fossil deposit is that animals became trapped in the
sediment in repeated miring events, which would favour the conservation of hindlimbs. Such a scenario is fully in accordance
with the taphonomic characteristics of the bone assemblage. 相似文献
914.
Melanin is the most common pigment in animal integuments and is responsible for some of the most striking ornaments. A central tenet of sexual selection theory states that melanin-based traits can signal absolute individual quality in any environment only if their expression is condition-dependent. Significant costs imposed by an ornament would ensure that only the highest quality individuals display the most exaggerated forms of the signal. Firm evidence that melanin-based traits can be condition-dependent is still rare in birds. In an experimental test of this central assumption, we report condition-dependent expression of a melanin-based trait in the Eurasian kestrel (Falco tinnunculus). We manipulated nestling body condition by reducing or increasing the number of nestlings soon after hatching. A few days before fledging, we measured the width of sub-terminal black bands on the tail feathers. Compared to nestlings from enlarged broods, individuals raised in reduced broods were in better condition and thereby developed larger sub-terminal bands. Furthermore, in 2?years, first-born nestlings also developed larger sub-terminal bands than their younger siblings that are in poorer condition. This demonstrates that expression of melanin-based traits can be condition-dependent. 相似文献
915.
916.
Sanne Van Beirendonck Bert Driessen Rony Geers 《Journal of Agricultural and Environmental Ethics》2013,26(1):259-272
Male piglets in Belgium are still castrated unanesthetized in the first week of life, but animal rights organizations, supermarkets, and some consumers no longer accept this method in terms of animal welfare, and are pushing the pig industry to apply available alternative methods. This major change in pig husbandry will increase production costs without a guarantee for return of investment by consumers. Therefore, it is important to know the opinion of consumers on this matter. A questionnaire was used to collect data from 1,018 people through face to face interviewing in Flanders. A Chi-square test and Fisher’s exact test were used to analyze the data. Results show that in spite of several media campaigns of animal welfare organizations over the past few years, still half of the Flemish respondents were not aware of the problem of unanesthetized piglet castration. However, after being informed, the majority wanted unanesthetized castration to be banned. Although the concern about animal welfare implications was very high, the willingness to pay extra for alternatives was low. 相似文献
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