Five-year study of the effects of simulated nitrogen deposition levels and forms on soil nitrous oxide emissions from a temperate forest in northern China.

PLoS One · 2017 · PMC5734751 · PMID 29253001

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a decreasing trendno p-value reported

The NH 4 + –N/NO 3 – –N ratio showed a decreasing trend in our study area [ 29 ], and so clarifying the response of soil N 2 O emission to different forms and levels of N addition now is necessary.

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