Litter inputs are expected to have a strong impact on soil N
2O efflux. This study aimed to assess the effects of the litter decomposition process and nutrient efflux from litter to soil on soil N
2O efflux in a tropical rainforest. A paired study with a control (L) treatment and a litter-removed (NL) treatment was followed for 2 years, continuously monitoring the effects of these treatments on soil N
2O efflux, fresh litter input, decomposed litter carbon (LCI) and nitrogen (LNI), soil nitrate (NO
3 ?–N), ammonium (NH
4 +–N), dissolved organic carbon (DOC), and dissolved nitrogen (DN). Soil N
2O flux was 0.48 and 0.32 kg N
2O–N ha
?1 year
?1 for the
L and NL treatments, respectively. Removing the litter caused a decrease in the annual soil N
2O emission by 33%. The flux values from the litter layer were higher in the rainy season as compared to the dry season (2.10 ± 0.28 vs. 1.44 ± 0.35 μg N m
?2 h
?1). The N
2O fluxes were significantly correlated with the soil NO
3 ?–N contents (
P < 0.05), indicating that the N
2O emission was derived mainly from denitrification as well as other NO
3 ? reduction processes. Suitable soil temperature and moisture sustained by rainfall were jointly attributed to the higher soil N
2O fluxes of both treatments in the rainy season. The N
2O fluxes from the
L were mainly regulated by LCI, whereas those from the NL were dominated jointly by soil NO
3 ? content and temperature. The effects of LCI and LNI on the soil N
2O fluxes were the greatest in the 2 months after litter decomposition. Our results show that litter may affect not only the variability in the quantity of N
2O emitted, but also the mechanisms that govern N
2O production. However, further studies are still required to elucidate the impacting mechanisms of litter decomposition on N
2O emission from tropical forests.
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