Purpose <p>N₂O is an agriculture-induced greenhouse gas with a high warming potential that is highly susceptible to tillage practices. In coastal reclaimed zones, extensive soil desalination measures may influence N₂O production, but few studies have focused on this aspect.</p> Methods <p>A 3-year field trial was conducted with four exogenous ameliorants (biochar [c + b], chicken manure [c + c], pig manure [c + p], and biochar-pig manure mixed [b + p]) combined with conventional fertilization (CK).</p> Results <p>After 3 consecutive years of input, all four exogenous ameliorants significantly promoted soil N₂O fluxes (compared to CK, mean N₂O fluxes of the c + b, c + c, c + p, and b + p treatments were increased by 262.34%, 257.19%, 118.93%, and 186.54%, respectively). Their promotion effect tended to increase as the experimental period progressed. With increased chicken manure, soil N₂O tended to increase gradually, whereas applying biochar, pig manure, and mixed biochar-pig manure significantly decreased N₂O fluxes. N₂O fluxes in the biochar treatment was primarily driven by the ever-decreasing soil salt content, whereas N₂O fluxes in the chicken manure treatment were primarily caused by the enhancement of vegetation activities. Pig manure input weakened the influence of both soil salts and nutrients on N₂O fluxes.</p> Conclusions <p>The addition of high-level of pig manure can help to desalinate soil while also reducing N₂O emissions.</p>