硝化抑制剂双氰胺对菜地土壤N_2O排放的影响

采用原状土柱试验研究了施用硝化抑制剂双氰胺（DCD）对菜地（小白菜和辣椒）土壤N2O排放的影响.结果表明,施用DCD能显著降低菜地土壤N2O排放通量和排放总量,小白菜未施用DCD时施氮处理土壤N2 O排放总量为0.22 kg.hm-2,施用DCD后则显著减少至0.11 kg.hm-2,相当于减少了49.33%的土壤N2...

Mitigation of Nitrous Oxide Emissions in Vegetable System by Treating Soil with Dicyandiamide, a Nitrification Inhibitor

Undisturbed soil monolith lysimeter was used to investigate the effectiveness of DCD (dicyandiamide) in reducing N2O emissions in vegetable (Chinese cabbage and pepper) field. Results showed that DCD significantly reduced total N2O emission in vegetable field. Total N2O emissions from the urea treatment without DCD reached 0.215 kg x hm(-2) for Chinese cabbage, and it reduced to 0.109 kg x hm(-2), equivalent to a 49.3% reduction. The total N2O emissions for pepper were much higher compared with those for Chinese cabbage. The total N2O emitted from the urea treatment was 2.32 kg x hm(-2) (without DCD) and it was reduced to 1.14 kg x hm(-2) with DCD application, representing a 50.9% reduction. In the control treatments where no urea was applied, the daily N2O flux was very low and it never exceeded 9 microg x (m2 x h) (-1) for Chinese cabbage and 22 microg x (m2 x h) (-1) for pepper, respectively, but DCD also reduced N2O emissions (33.5% for Chinese cabbage and 33.4% for pepper). In addition, the urea-N emission factor (EF) was 0.15%, 0.99% for Chinese cabbage and pepper without DCD, respectively, and it was reduced to 0.07%, 0.52% when DCD was applied. These results demonstrated the potential of using nitrification inhibitors (DCD) to mitigate N2O emissions in vegetable system.