Alpha and beta diversities are widely used to assess microbial community dynamics. However, little is known about the optimum sampling times for microbial alpha and beta diversity analysis between various cropland management systems across seasons, and whether changes in alpha and beta diversities of bacteria and fungi in response to temporal variation are synchronized. To investigate shifts in microbial alpha and beta diversities between soil environments caused by cropland management during the transition from winter to summer, a long-term field experiment was conducted under three different conditions: (1) natural regeneration after the cropland was abandoned, (2) mineral fertilizer application alone, and (3) 7500 kg ha⁻¹ of wheat straw combined with mineral fertilizers incorporated into the cropland. Illumina HiSeq sequencing was performed, targeting the bacterial 16S rRNA V4-5 and fungal ITS1 regions. The results showed that the alpha and beta diversities of bacteria and fungi responded differently to seasonal change, and the temporal changes in beta diversity between treatments were not synchronized with those of alpha diversity. Compared to fungi, seasonal change had a more complex influence on soil bacterial beta diversity due to the interaction between land management and sampling time. Thus, using only one or a few sampling times within a season is an oversimplified approach when assessing bacterial beta diversity between land management systems and the impacts of environmental factors on bacterial diversity. For soil fungi, it was possible to assess their beta diversity between management practices without considering temporal variation. This research provides an opportunity to assess the effects of temporal variation on microbial diversity under various land management styles.

Alpha 和 Beta 多样性被广泛用于评估微生物群落动态。然而，关于不同季节农田管理系统之间微生物 α 和 β 多样性分析的最佳采样时间，以及细菌和真菌的 α 和 β 多样性响应时间变化的变化是否同步，我们知之甚少。为了研究农田管理在冬夏过渡期间土壤环境中微生物 α 和 β 多样性的变化，在三种不同条件下进行了长期田间试验：（1）耕地废弃后的自然再生，（2 ) 单独施用矿物肥料，以及 (3) 7500 kg ha ^-1小麦秸秆与矿物肥料结合到农田中。进行了 Illumina HiSeq 测序，靶向细菌 16S rRNA V4-5 和真菌 ITS1 区域。结果表明，细菌和真菌的α和β多样性对季节变化的反应不同，处理间β多样性的时间变化与α多样性的时间变化不同步。与真菌相比，由于土地管理和采样时间之间的相互作用，季节变化对土壤细菌β多样性的影响更为复杂。因此，在评估土地管理系统之间的细菌 β 多样性以及环境因素对细菌多样性的影响时，在一个季节内仅使用一个或几个采样时间是一种过于简单的方法。对于土壤真菌，可以在不考虑时间变化的情况下评估管理实践之间的 beta 多样性。这项研究为评估不同土地管理方式下时间变化对微生物多样性的影响提供了机会。