不同施肥和保水措施对油茶土壤N2O排放的影响

为探究不同施肥和保水措施对油茶土壤N_2O排放的影响,采用静态暗箱-气相色谱法,设置对照(B0CK)、氮肥(N,0.13 g N·kg~(-1))、磷肥(P,0.065 g P·kg~(-1))、氮磷肥(NP,0.13 g N·kg~(-1)+0.065 g P·kg~(-1))、低复合保水材料(生物炭和聚丙烯酰胺,B1,每盆13.65 g炭+1.35 g聚丙烯酰胺)、高复合保水材料(生物炭和聚丙烯酰胺,B2,每盆27.30 g炭+2.70 g聚丙烯酰胺)、低复合保水材料和N(NB1)、高复合保水材料和N(NB2)、低复合保水材料和P(PB1)、高复合保水材料和P(PB2)、低复合保水材料和NP(NPB1)、高复合保水材料和NP(NPB2),共12个处理,进行不同施肥和保水措施下土壤N_2O排放的差异比较。结果表明,N、P添加均显著增加土壤N_2O的累积排放量,NP添加与对照无差异。施加复合保水材料抑制土壤N_2O的排放,随着复合保水材料施用量的增加,土壤N_2O的排放显著降低,与对照相比,B1和B2处理N_2O减排50%以上。N添加条件下,与对照相比,添加复合保水材料NB1、NB2的N_2O累积排放显著降低。P与复合保水材料无交互作用。N、P和复合保水材料对土壤N_2O累积排放量具有显著作用,在NP同施时,与对照相比,添加复合保水材料NPB1、NPB2的N_2O累积排放分别降低了1.18%、30.69%。因此,高复合保水材料类型的施肥措施对减少油茶土壤N_2O排放具有重要意义,从而对缓解全球气候变化具有重要影响。

Effects of different fertilization and water retention measures on N2O emission from Camellia oleifera soil

To investigate the effects of different fertilization and water conservation measures on N₂O emissions from Camellia oleifera soil, tests were conducted using Camellia seedings, with a static dark box-gas chromatography method, a total of 12 treatments of different fertilizer and water conservation, including control(B0CK), nitrogen fertilizer(N), phosphate fertilizer(P), nitrogen and phosphorus fertilizer(NP), composite water-retaining material (biochar and polyacrylamide, B1), high composite materials (biochar and polyacrylamide, B2), low composite materials and nitrogen fertilizer(NB1)and high composite materials and nitrogen fertilizer(NB2), low composite materials and phosphate(PB1), high composite materials and phosphate(PB2), low composite materials and high nitrogen and phosphate(NPB1), composite materials and nitrogen phosphorus(NPB2), was set to determine the difference of soil N₂O emissions. Results showed that the addition of N and P significantly increased the cumulative emissions of soil N₂O, while the addition of N and P showed no difference with the control sample. Composite water-retaining materials were applied to inhibit soil N₂O emissions. With the increase of application amount of composite water-retaining materials, soil N₂O emissions were significantly reduced. Compared with the control, B1 and B2 reduced N₂O emissions by more than 50%, respectively. When N was added, compared with control, the cumulative N₂O emissions of NB1 and NB2 with composite water-retaining materials were significantly reduced, respectively. P had no interaction with the composite water-retaining material. N, P, and composite water-retaining materials had significant effects on the cumulative N₂O emissions of soil. When N and P was applied together, compared with the control, the cumulative N₂O emissions of composite water-retaining materials NPB1 and NPB2 were reduced by 1.18% and 30.69%, respectively. Therefore, the application of fertilizer with high composite water-retaining materials is of great significance in reducing the N₂O emissions of Camellia oleifera soil, thereby having an important impact on mitigating global climate change.