Straw return has been found to benefit soil fertility and crop yield, however, by which it affects microbial communities to mediate soil factors driving crop yields under maize continuous cropping systems in dryland areas is still unclear. To fill this gap, a 6-year field experiment was established with five straw return amounts (T0, T1, T2, T3, and T4, representing 0, 3000, 6000, 9000, and 12,000 kg ha−1 of straw, respectively), and investigated the effects of on soil properties, enzymes, bacterial community composition and diversity, and crop yields. Our analysis showed that soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents significantly increased by 1–8 %, 5–25 %, and 2–9 % under straw return treatments, respectively, compared to the T0, and soil catalase, urease, and alkaline phosphatase activities increased by at least 34.00 %. Additionally, crop yield significantly increased by 4.23–12.00 % under T1-T4 treatments, and showed highly significant relationships with SOC, TN, and TP. Importantly, we found straw return significantly altered the community of bacteria involved in the carbon and nitrogen cycle, and their abundance of strong responses depending on the amounts of straw return. For example, straw input increased the abundance of Proteobacteria (+2.64–5.57 %), Acidobacteria (+3.82–13.83 %), and Bacteroidetes (+15.37–30.49 %). Similarly, the amount of straw application increased the bacterial diversity indexes (Shannon, 2.65–10.93 %; Chao1, 13.47–18.50 %), and had significant positive correlations with SOC, TN, and TP contents. Structural equation models (SEM) revealed that straw return management practice had positive and indirect effects on crop yields by influencing soil properties or the bacteria community. In conclusion, our findings revealed common associations and variations of bacterial community diversity with soil factors and crop yields at different straw return rates, and these findings provide insights and options for the development of better straw return strategies and sustainable agriculture in semi-arid regions.

中文翻译：

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秸秆还田可以通过调节土壤细菌和改善干旱和半干旱地区的土壤特性来提高玉米产量


已发现秸秆还田有利于土壤肥力和作物产量，然而，在旱地玉米连作系统中，秸秆还田会影响微生物群落以介导驱动作物产量的土壤因素，目前尚不清楚。为了填补这一空白，建立了一个为期 6 年的田间试验，使用了 5 个秸秆还田量（T0、T1、T2、T3 和 T4，分别代表 0、3000、6000、9000 和 12,000 kg ha-1 的秸秆），并研究了它们对土壤特性、酶、细菌群落组成和多样性以及作物产量的影响。我们的分析表明，与 T0 相比，秸秆还田处理下土壤有机碳 （SOC）、全氮 （TN） 和全磷 （TP） 含量分别显著增加了 1-8 %、5-25 % 和 2-9 %，土壤过氧化氢酶、脲酶和碱性磷酸酶活性至少增加了 34.00 %。此外，在 T1-T4 处理下，作物产量显著提高了 4.23–12.00%，并与 SOC、TN 和 TP 呈高度显著的关系。重要的是，我们发现秸秆还田显着改变了参与碳氮循环的细菌群落，以及它们根据秸秆还田量而产生的强烈反应的丰度。例如，秸秆输入增加了变形菌门 （+2.64–5.57 %）、酸杆菌门 （+3.82–13.83 %） 和拟杆菌门 （+15.37–30.49 %） 的丰度。同样，秸秆施用量增加了细菌多样性指数（Shannon，2.65–10.93 %;Chao1,13.47–18.50 %），并且与 SOC、TN 和 TP 含量呈显著正相关。结构方程模型 （SEM） 显示，秸秆还田管理实践通过影响土壤特性或细菌群落对作物产量产生积极和间接影响。 综上所述，我们的研究结果揭示了不同秸秆还田率下细菌群落多样性与土壤因子和作物产量的共同关联和变化，这些发现为在半干旱地区制定更好的秸秆还田策略和可持续农业提供了见解和选择。