Sun He-Yang, Wan Zhong-Mei, Liu De-Yan, Liao Xia, Ding Wei-Xin
College of Earth Sciences, Jilin University, Changchun 130061, China.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Huan Jing Ke Xue. 2020 Mar 8;41(3):1474-1481. doi: 10.13227/j.hjkx.201908008.
The North China Plain is an important grain production area in China. Due to the low content of soil organic carbon, increasing the application rate of nitrogen fertilizer would not lead to a continuous increase of maize yield at present. The combined application of organic fertilizer and inorganic fertilizer is widely regarded as a measure to simultaneously increase grain yield and soil organic carbon; however, the effect of organic fertilizer and inorganic fertilizer application on NO emissions from farmland in the North China Plain is unclear. Here, NO emissions and crop yields in cropland under the combined application of different types and rates of organic fertilizers plus inorganic N fertilizer were measured in the North China Plain. The field experiment included eight treatments:no N fertilizer (CK), inorganic fertilizer (NPK), 40% cow manure N plus 60% inorganic fertilizer N (CM), 40% chicken manure N plus 60% inorganic fertilizer N (FC), 40% pig manure N plus 60% inorganic fertilizer N (FP), 20% cow manure N plus 80% inorganic fertilizer N (1/2CM), 20% chicken manure N plus 80% inorganic fertilizer N (1/2FC), and 20% pig manure N plus 80% inorganic fertilizer N (1/2FP). The NO fluxes were significantly correlated with soil water-filled pore space during the maize season (<0.05). There was a significant linear relationship between NO fluxes and soil dissolved organic carbon content during the maize season in all treatments except the NPK treatment. In the maize season, NO emission was 0.50 kg·hm under CK treatment, and increased to 2.28 kg·hm under NPK treatment. However, when the proportion of manure N to total N applied was reduced from 40% to 20%, NO emissions were significantly reduced by 33.6%, 43.7%, and 12.1% under 1/2CM, 1/2FC, and 1/2FP treatments, respectively. The difference in application rate of organic manure N did not significantly affect maize yield. The reduction of NO emission at the low manure application rate compared with the high manure application rate was likely due to the decrease in dissolved organic carbon in soils.
华北平原是中国重要的粮食产区。由于土壤有机碳含量较低，目前增加氮肥施用量不会导致玉米产量持续增加。有机肥料与无机肥料配合施用被广泛认为是一种既能提高粮食产量又能增加土壤有机碳的措施；然而，有机肥料和无机肥料施用于华北平原农田对一氧化氮（NO）排放的影响尚不清楚。在此，对华北平原不同类型和施用量的有机肥料与无机氮肥配合施用下农田的NO排放和作物产量进行了测定。田间试验包括8个处理：不施氮肥（CK）、无机肥（NPK）、40%牛粪氮 + 60%无机肥氮（CM）、40%鸡粪氮 + 60%无机肥氮（FC）、40%猪粪氮 + 60%无机肥氮（FP）、20%牛粪氮 + 80%无机肥氮（1/2CM）、20%鸡粪氮 + 80%无机肥氮（1/2FC）、20%猪粪氮 + 80%无机肥氮（1/2FP）。在玉米生长季，NO通量与土壤充水孔隙度显著相关（<0.05）。除NPK处理外，所有处理在玉米生长季NO通量与土壤溶解有机碳含量之间均存在显著的线性关系。在玉米生长季，CK处理下NO排放量为0.50 kg·hm，NPK处理下增加到2.28 kg·hm。然而，当粪肥氮占总施氮量的比例从40%降至20%时，1/2CM、1/2FC和1/2FP处理下的NO排放量分别显著降低了33.6%、43.7%和12.1%。有机肥氮施用量的差异对玉米产量没有显著影响。与高粪肥施用量相比，低粪肥施用量下NO排放量的降低可能是由于土壤中溶解有机碳的减少。
