The Innovation Team of Improvement and Amelioration of Soil Fertility of the Institute of Agricultural Resources and Regional Planning (IARRP), the Chinese Academy of Agricultural Sciences (CAAS) recently revealed the key processes of lime application regulating N2O emission and its response to climate warming in acidic red soil, so as to help develop appropriate management strategies for effective greenhouse gas mitigation as well as acidification alleviation.

The research results were published in the International Journal of Soil Science (Geoderma).

Due to high-intensity agricultural production and large amouts of chemical nitrogen fertilizer application, the acidification of red soil has been intensified, thus reducing soil fertility and crop yields in southern China. Lime application effectively alleviates the acidification of red soil, and improves soil fertility and crop yield. Long-term lime application can affect soil carbon availability and microbial nitrogen transformation, thus regulating greenhouse gas N2O emission and its response to climate warming. However, there remains a knowledge gap regarding how labile C addition regulates the liming effects on the emission and temperature sensitivity (Q10) of N2O from acidic soils.

In the present study, the limed and unlimed acidic soils collected from a long-term field trial, amended with and without glucose as labile C, were incubated at 15℃  and 25℃ to investigate the responses of the emission and Q10 of N2O and the underlying mechanisms. Results showed that liming had no effect on the emission and Q10 of N2O without labile C addition. While after labile C addition, the emission and Q10 of N2O were reduced by 13–28% and 17%, respectively, in the limed relative to unlimed soils. These results suggested that the mitigation effect of liming on N2O emission can mainly be seen when labile C is highly available in soils. Long-term liming potentially reduced N2O emission and its Q10 via decreased (nirK+nirS)/(nosZI+nosZII) ratio in acidic soils in the presence of labile C.

Professor Wu Lei of the IARRP is the first author of the paper, and professor Zhang Wenju is the corresponding author.

This research was financially supported by the National Natural Science Foundation of China, the Fundamental Research Funds for Central Non-profit Scientific Institution and the Innovation Talent Promotion Program of Ministry of Science and Technology.

Paper link: https://www.sciencedirect.com/science/article/pii/S0016706122003391

Liming regulates the emission and temperature sensitivity of nitrous oxide