Ditch-buried straw return (DB-SR) is a novel soil tillage and fertility-building practice, which may allow for the formation of a straw layer structure in rice–wheat rotation systems. However, it is presently unknown how the straw layer affects soil physicochemical and microbial processes in the interface between straw layer and bulk soils. Thus, we conducted a field experiment from 2008 to 2014 to determine whether there were changes in soil structure, temperature, available nitrogen, and microbial properties in the soil layer close to the straw layers (± 5 cm). Three treatments were included: control with no-till and straw removal (CK), ditch-buried straw return to a depth of 20 cm (DB-SR-20), and ditch-buried straw return to a depth of 40 cm (DB-SR-40). Our results showed that soil macroaggregate formation was increased with the duration of straw return in the soils 5 cm below the straw layers under DB-SR-20 and above the straw layers under DB-SR-40. The straw layers could significantly increase soil temperature below the straw layers, but a larger increase was observed for DB-SR-40 than DB-SR-20. We also found that DB-SR-20 largely increased the NH₄⁺ concentration in both the soil layers above and below the straw layers, but DB-SR-40 only increased NO₃⁻ in the soils above the straw layers. In addition, the catabolic profile of soil microbial communities was largely affected by the straw layers, but the effects decreased with the duration of the treatment. These findings suggest that the straw layer largely alters the spatio-temporal processes of physicochemical and microbial properties in the interface soils after long-term implementation of ditch-buried straw return. Some of the positive alterations may cascade to facilitate crop growth and enhance the productivity of rice-wheat rotation systems.

沟埋秸秆还田（DB-SR）是一种新颖的土壤耕作和增肥措施，可以在稻麦轮作系统中形成秸秆层结构。然而，目前尚不清楚秸秆层如何影响秸秆层与大块土壤之间的界面中的土壤物理化学和微生物过程。因此，我们从2008年至2014年进行了田间试验，以确定靠近稻草层（±5 cm）的土壤层中土壤结构，温度，有效氮和微生物特性是否发生变化。包括三种处理：免耕和秸秆清除（CK）对照，沟埋秸秆返回深度为20厘米（DB-SR-20）和沟埋秸秆返回深度为40厘米（DB） -SR-40）。我们的结果表明，在DB-SR-20下低于秸秆层5 cm和DB-SR-40下高于秸秆层5 cm的土壤中，随着秸秆还田时间的增加，土壤大团聚体的形成增加。稻草层可显着提高稻草层以下的土壤温度，但观察到DB-SR-40的增加幅度大于DB-SR-20。我们还发现DB-SR-20大大增加了NH₄ ⁺浓度在上方和稻草层下面的土层两者，但DB-SR-40只增加NO ₃ ^-中的吸管层以上的土壤。此外，秸秆层对土壤微生物群落的分解代谢特性影响很大，但随着处理时间的延长，其影响降低。这些发现表明，长期实施沟埋秸秆还田后，秸秆层极大地改变了界面土壤的物理化学和微生物特性的时空过程。一些积极的变化可能会级联以促进作物生长并提高稻麦轮作系统的生产力。