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421.
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Suvi Monni Paula Perälä Kristiina Regina 《Mitigation and Adaptation Strategies for Global Change》2007,12(4):545-571
According to the United Nations Framework Convention on Climate Change (UNFCCC) and Kyoto Protocol under it, industrial countries
have to estimate their greenhouse gas emissions annually, and assess the uncertainties in these estimates. In Finland, agricultural
methane (CH4) and nitrous oxide (N2O) emissions represent 7% of anthropogenic greenhouse gas emissions, and globally the share is much higher. Agriculture is
one of the most uncertain emission categories (representing over 20% of greenhouse gas inventory uncertainty in Finland),
due to both high natural variability of the emission sources and poor knowledge of the emission-generating processes. In this
paper, we present an uncertainty estimate of agricultural CH4 and N2O emissions from Finland in 2002. Uncertainties were estimated based on measurement data, literature and expert judgement,
and total uncertainty in agriculture was calculated using Monte Carlo simulation. According to the calculations, agricultural
CH4 and N2O emissions from Finland were 3.7 to 7.8 Tg carbon dioxide (CO2) equivalents, 5.4 Tg being the mean value.Estimates of CH4 emissions are more reliable than those of N2O. N2O from agricultural soils was the most uncertain emission category, and the uncertainty was not reduced by using available
national measurement data of N2O fluxes. Sensitivity study revealed that the uncertainty in total agricultural inventory could be 7% points lower, if more
accurate emission estimation methods were used, including 1) improved data collection in area estimates of organic soils,
2) climate-specific methods for N2O from agricultural soils as already presented in literature, and 3) more detailed CH4 estimation methods for enteric fermentation which can be achieved by investigating national circumstances and digestible
systems of animals in more detail. 相似文献
423.
DM Peter Lorenz Rainer Bollmann Georg Klaus Hinkel Marco Mächler Gabriele Siegert Gudrun Stamminger Jörg Wendisch Sabine Ziemer 《黑龙江环境通报》1991,11(11):819-825
The study of the fetal platelet count and size can, according to the literature, be used for the prenatal diagnosis of the Wiskott-Aldrich syndrome (WAS). So far, no affected fetuses have been identified by this method. All pregnancies in which this method had been applied to resulted, as correctly predicted, in the birth of normal children. Here we report on a familial case of WAS where the haematological parameters failed to reveal the affected second child. Hence we assume that the platelet count and size of platelets remain normal in fetuses with WAS to the gestational age of 22 weeks and cannot be used for prenatal diagnosis. 相似文献
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