不同耕作模式下麦田土壤温室气体排放和小麦产量

  【目的】  研究不同耕作模式对麦田土壤温室气体排放和小麦产量的影响，以期为实现小麦生产中固碳减排、绿色高产提供参考。  【方法】  供试小麦品种为‘济麦22’。本研究基于2007年的耕作模式田间定位试验，于2020—2021年小麦生长季选择4种耕作模式，即常年翻耕 (P)、常年旋耕 (R)、常年少免耕 (S)和隔两年深松+少免耕 (SS)。采集0—45 cm土层土壤样品，测定不同耕作模式下直径>0.25 mm的土壤团聚体、土壤有机碳和土壤微生物量碳含量，利用静态暗箱—气相色谱法测定温室气体排放通量，成熟期测定籽粒产量及产量构成因素。  【结果】  SS处理0—15 cm土层直径>0.25 mm的土壤团聚体含量与S处理无显著差异，显著高于P和R处理，15—45 cm土层显著高于其他处理；0—45 cm土层土壤有机碳含量和土壤微生物量碳含量最高；小麦生长季温室气体全球变暖潜力SS处理较S处理增加了7.9%，较P和R处理分别降低了12.2%和7.3%；SS处理温室气体排放强度较P、R和S处理分别减少了28.6%、28.6%和16.7%。在成熟期，SS处理的千粒重较P、R和S处理分别提高了4.7%、8.7%和9.6%，籽粒产量较P、R和S处理分别增加了7.1%、14.2%和19.4%。  【结论】  隔两年深松+少免耕 (SS) 处理增加了0—45 cm土层直径>0.25 mm的土壤团聚体含量，提高了土壤有机碳和微生物量碳含量，降低了温室气体排放强度，并获得小麦高产。综上所述，隔两年深松+少免耕 (SS) 处理是兼顾产量和环境效益的最佳耕作模式。

Soil greenhouse gas emission and yield in wheat fields under different tillage patterns

  【Objectives】  The effects of different tillage patterns on soil greenhouse gas emission and yield in wheat fields were studied in order to provide a reference for achieving high carbon sequestration and yield.   【Methods】  The Jimai 22 wheat variety was tested under four tillage treatments (perennial plowing tillage, P; perennial rotary tillage, R; perennial minimum and no tillage, S; and minimum and no tillage with a 2-year subsoiling interval, SS) during the wheat growing seasons of 2020 and 2021. Soil samples of 0–45 cm soil layers were collected in each to determine the content of soil aggregates with diameter >0.25 mm as well as the content of soil organic carbon and microbial biomass carbon across the tillage treatments. Greenhouse gas emission fluxes were measured using static closed chamber-gas chromatography. Grain yield and yield components were measured at maturity.   【Results】  The content of soil aggregate with diameter >0.25 mm in the 0–15 cm soil layer under SS treatment was similar to that under S treatment, but higher than those in P and R treatments. The soil aggregate in 15–45 cm soil layer was significantly higher than those of other treatments. The content of soil organic carbon and microbial biomass carbon in the 0–45 cm soil layer treated with SS was the highest. In the wheat growing season, the global warming potential of greenhouse gases under SS treatment increased by 7.9%, compared with S treatment, and decreased by 12.2% and 7.3% compared with P and R treatments, respectively. Compared with P, R, and S treatments, the greenhouse gas emission intensity of SS treatment decreased by 28.6%, 28.6%, and 16.7%, respectively. At maturity, the 1000-kernel weight under SS treatment increased by 4.7%, 8.7%, and 9.6%, compared with P, R, and S treatments, while the grain yield of SS treatment increased by 7.1%, 14.2%, and 19.4%, respectively.   【Conclusions】  SS treatment increased the content of aggregates with diameter >0.25 mm in the 0–45 cm soil layer, as well as the content of soil organic carbon and microbial biomass carbon, reduced the intensity of greenhouse gas emissions and promoted higher yield. To sum up, the SS pattern is the best tillage treatment for better yield and environmental benefits.