Insects produce less ammonia than pig and poultry farming, ten times less methane than livestock, and 300 times less nitrous oxide.

昆虫产生的氨比猪和家禽少，它们产生的甲烷比家畜少十倍，而产生的一氧化二氮比家畜少三百倍。

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The problem with this method is that methane and nitrous oxide emissions fluctuate strongly in time and space.

这种方法的问题是，甲烷和一氧化氮的排放量在不同时间和空间波动很大。

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The emission of methane and nitrous oxide is largely the result of agricultural activities; nitrous oxide from fertilisers and methane mostly from cows.

甲烷和一氧化二氮的排放主要是农业活动的结果：一氧化二氮源于化肥而甲烷主要来自奶牛。

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The WMO data, meanwhile, confirms that atmospheric concentrations of the three gases principally responsible for the man-made component of the greenhouse effect - carbon dioxide, methane, and nitrous oxide - all rose during 2009.

BBC: Modest hopes for climate summit, as gas levels rise

The greenhouse gases surveyed include not only carbon dioxide but also methane (CH4), nitrous oxide (N2O), ozone (O3), and fluoride-containing gases that contribute to climate change.

FORBES: EPA Greenhouse Gas Inventory Shows 6 Percent Drop In CO2