No-tillage (NT) practice is increasingly adopted to improve soil health and sustainability. However, long-term NT may increase soil organic carbon (SOC) and nutrient stratification, soil acidification, compaction, and herbicide resistance in weeds. Targeted strategic disturbance of continuous no-tillage is occasionally practiced to overcome challenges of long-term no-tillage, yet limited information is available on their impacts on SOC and nitrogen (N) components. We evaluated the response of SOC and N fractions to different tillage practices after the imposition of one-time strategic minimum tillage operation (i.e., stubble mulch tillage: SMT) in a continuous NT system in semi-arid drylands. Tillage treatments included conventional tillage (CT), NT, SMT, and strip-tillage (ST). The CT, NT, and ST plots were established in 2013, and SMT plots were established with only one pass of stubble mulch tillage in september of 2019 in long-term NT plots. Soil samples were collected from 0 to 15 and 15–30 cm depth of each plot before SMT and 2-days, 7-months, 14-months, 19-months, and 26-months after SMT implementation. The CT management resulted in 12–27% and 11–16% lower SOC concentration than under NT, SMT, and ST in 0–15 and 15–30 cm depth, respectively. The CT and ST had 22–53%, 44–79%, and 43% greater soil inorganic N than NT and SMT after 2-days, 7-months, and 19-months, respectively, in 0–15 cm depth. The 3d-carbon dioxide-carbon (CO₂-C) was 32–65%, 48–65%, 62–102%, and 122–195% greater under CT and ST than under NT and SMT after 2-days, 7-months, 19-months, and 26-months, respectively, in 0–15 cm depth. The microbial biomass carbon (MBC) showed varying responses, with 31–64% lower MBC after 2-days and 26-months, but it was 35–39% greater after 7-months under CT than under NT and SMT. There was no difference between NT and SMT systems on SOC and N fractions for most of the samplings. Further research may reveal how often SMT can be utilized in a long-term NT system without negative impacts on soil properties in semi-arid dryland cropping systems. This study showed one stubble mulch tillage after six years of continuous NT did not affect SOC and N concentrations in 0–30 cm depth.

越来越多地采用免耕 (NT) 做法来改善土壤健康和可持续性。然而，长期 NT 可能会增加土壤有机碳 (SOC) 和养分分层、土壤酸化、压实和杂草的除草剂抗性。偶尔会采用连续免耕的有针对性的战略干扰来克服长期免耕的挑战，但关于它们对 SOC 和氮 (N) 成分的影响的信息有限。我们评估了在半干旱旱地的连续 NT 系统中实施一次性战略性最少耕作操作（即残茬覆盖耕作：SMT）后，SOC 和 N 组分对不同耕作方式的响应。耕作处理包括常规耕作 (CT)、NT、SMT 和条状耕作 (ST)。CT、NT、ST地块建立于2013年，和 SMT 地块是在 2019 年 9 月的长期 NT 地块中仅通过一次茬覆盖耕作而建立的。在 SMT 之前以及 SMT 实施后 2 天、7 个月、14 个月、19 个月和 26 个月，从每个地块的 0 到 15 厘米和 15-30 厘米深度收集土壤样本。CT 管理导致 0-15 和 15-30 cm 深度的 SOC 浓度分别比 NT、SMT 和 ST 低 12-27% 和 11-16%。在 0-15 厘米深度 2 天、7 个月和 19 个月后，CT 和 ST 的土壤无机氮含量分别比 NT 和 SMT 高 22-53%、44-79% 和 43%。3d-二氧化碳-碳 (CO SMT 实施后 26 个月。CT 管理导致 0-15 和 15-30 cm 深度的 SOC 浓度分别比 NT、SMT 和 ST 低 12-27% 和 11-16%。在 0-15 厘米深度 2 天、7 个月和 19 个月后，CT 和 ST 的土壤无机氮含量分别比 NT 和 SMT 高 22-53%、44-79% 和 43%。3d-二氧化碳-碳 (CO SMT 实施后 26 个月。CT 管理导致 0-15 和 15-30 cm 深度的 SOC 浓度分别比 NT、SMT 和 ST 低 12-27% 和 11-16%。在 0-15 厘米深度 2 天、7 个月和 19 个月后，CT 和 ST 的土壤无机氮含量分别比 NT 和 SMT 高 22-53%、44-79% 和 43%。3d-二氧化碳-碳 (CO₂ -C) 在 2 天、7 个月、19 个月和 26 个月后，在 CT 和 ST 下比在 NT 和 SMT 下高 32–65%、48–65%、62–102% 和 122–195% -月，分别在 0–15 厘米深度。微生物生物量碳 (MBC) 显示出不同的反应，2 天和 26 个月后 MBC 降低 31-64%，但 CT 下 7 个月后比 NT 和 SMT 下高 35-39%。对于大多数样本，NT 和 SMT 系统在 SOC 和 N 分数方面没有差异。进一步的研究可能会揭示 SMT 在长期 NT 系统中的使用频率，而不会对半干旱旱地种植系统的土壤特性产生负面影响。这项研究表明，连续 NT 六年后，一茬覆盖耕作不会影响 0–30 cm 深度的 SOC 和 N 浓度。