摘要： 为合理利用秸秆并进行碳固定，在青岛农业大学长期定位秸秆还田试验站开展田间试验，设置5个处理，包括相同施氮条件下小麦、玉米两季秸秆还田（WCN）和一季小麦秸秆还田（WN），小麦玉米两季秸秆还田（WC），对照（CK）及单施有机肥处理（M），测定玉米-小麦轮作收获后土壤中的总有机碳、土壤的活性碳组分（轻组有机碳、颗粒有机碳、水溶性有机碳、易氧化有机碳）、土壤团聚体、土壤团聚体有机碳含量。结果表明，土壤总有机碳及各活性碳组分含量均表现为M > WCN > WN > WC > CK，其中M处理和WCN处理总有机碳含量在小麦季和玉米季较对照分别提高了99.78%，117.94%和84.73%，98.03%，差异显著；土壤水稳性团聚体0.25~2.00 mm粒级占比、团聚体几何平均直径、平均质量直径及各粒级团聚体有机碳含量亦表现为M > WCN > WN > WC > CK，与对照相比，M处理和WCN处理在0.25~2.00 mm粒级占比提高了10.2，9.6百分点，几何平均直径和平均质量直径分别提高了53.1%，45.8%和10.9%，5.4%，各粒级有机碳含量分别提高129.9%~330.2%，69.0%~188.4%。综上，有机肥处理及两季秸秆还田配施氮肥能显著提高土壤有机碳及各活性有机碳含量，有利于土壤大团聚体的形成，提高了团聚体稳定性和各粒级团聚体有机碳含量。

关键词: 秸秆还田, 土壤总有机碳, 土壤活性碳组分, 土壤团聚体

Abstract: In order to make reasonable use of straw and carbon fixation, this study conducted field experiments at a long-term straw return field trial station in Qingdao Agricultural University. Five treatments were set up, which included two seasons of wheat and corn straw return with nitrogen fertilizer application (WCN), one season of wheat straw return with the same nitrogen fertilizer application (WN), two seasons of wheat and corn straw return (WC), control (CK), and single application of organic fertilizer (M), the total organic carbon in the soil and the active carbon components (light organic carbon, particulate organic carbon, water-soluble organic carbon, easily oxidizable organic carbon), soil aggregates, and soil aggregate organic carbon content were determined. The results showed that the contents of total soil organic carbon and various active carbon components all represented as M > WCN > WN > WC > CK.Compared with the CK,the total organic carbon content of M and WCN treatment in the wheat season and maize season were significantly increased by 99.78% and 117.94%,84.73% and 98.03%, respectively. The proportion of 0.25-2.00 mm soil water-stable aggregates, the geometric mean diameter of the aggregates, the average mass diameter and the organic carbon content of each aggregate were also expressed as M > WCN > WN > WC > CK. Compared with the CK, the proportion of 0.25-2.00 mm soil water-stable aggregates of M treatment and WCN treatment in the wheat season and maize season increased by 10.2,9.6 percentage point respectively; the geometric average diameter and average mass diameter increased by 53.1% and 45.8%, 10.9% and 5.4%, the organic carbon content of each grain size increased by 129.9%-330.2%, 69.0%-188.4%. In summary, organic fertilizer treatment and two seasons of straw return to the field with nitrogen fertilizer application could significantly increase the content of soil organic carbon and various active organic carbons, which was conducive to the formation of large aggregates in the soil, and improved the stability of the aggregates and the organic carbon content of the various aggregates.

Key words: Straw returning, Soil total organic carbon, Soil activated carbon component, Soil aggregate

中图分类号: 

• S142