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The measurement of faecal glucocorticoid metabolites is used as a non-invasive technique to study stress in animal populations. They have been used most widely in mammals, and mammalian studies have also treated issues such as sample stability and storage methods. In birds, faecal corticosterone metabolite (CM) assays have been validated for a small number of species, and adequate storage under field conditions has not been addressed explicitly in previous studies. Furthermore, while it is well-established that baseline plasma corticosterone levels in birds rise with declining body condition, no study so far investigated if this relationship is also reflected in faecal samples. We here present data of a field study in wild Upland geese Chloephaga picta leucoptera on the Falkland Islands, testing different storage methods and investigating the relationship of faecal CM concentrations to body condition and reproductive parameters. We found that faecal CM measures are significantly repeatable within individuals, higher in individuals with lower body condition in both male and female wild Upland geese and higher in later breeding females with smaller broods. These results suggest that measuring faecal CM values may be a valuable non-invasive tool to monitor the relative condition or health of individuals and populations, especially in areas where there still is intense hunting practice.  相似文献   
473.
This article discusses nitrogen oxide emissions from various types of boilers in Finland. The boilers have been classified into 61 classes according to their size, combustion technique, and main fuel. A specific emission coefficient (ng NO2/J = mg NO2/MJ) for each class has been determined, based on literature surveys and actual measurements. The total NOX emission has been calculated for each class, using the emission coefficient and energy statistics. The effect of various techniques for emission reduction has also been investigated. The development of NOX emissions has been estimated for both the case where no preventing actions have been taken and for four defined cases where alternative reduction measures are assumed

The total NOX emission from energy production in Finland was 107,000 tons NO2 in 1987. Seventy-five percent of this amount originated in boilers larger than 1 MWfuel effect (input effect), and the rest in smaller boilers and industrial processes. The most important boiler classes from the NOX emission’s point of view were coal-fired boilers, with an emission of approximately 38,000 tons NO2, peat-fired boilers and boilers fired with a mixture of fuels, emitting approximately 12,000 tons NO2 each.

By 2005, the total NOX emission from energy production would increase 50 percent to approximately 160,000 tons if left uncontrolled. The emission level would be 140,000 tons if primary reduction techniques are applied, and 110,000 tons NO2, if catalytic NOX reduction devices are installed in boilers larger than 300 MW.  相似文献   
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