Soil microbial communities and biophysical properties were analyzed in an irrigated maize monoculture after the introduction of three legume cover crops under conventional and reduced tillage, revealing that soil management had a stronger impact on microbial structure than cover crop species.

Cover cropping is a practice commonly associated with regenerative agriculture that has been implemented with greater or lesser intensity for approximately a century. Cover crops do not only provide a series of benefits and ecosystem services to the cash crops, but also contribute to the regeneration of the microbial component of soils and contribute to overcoming their microbiological exhaustion when they are subjected to very intensive cultural practices. The present work analyzes certain soil biophysical properties and the composition and structure of microbial communities associated with the introduction of cover crops based on three different leguminous species (Vicia villosa, Vicia sativa and Pisum sativum) in a 2-ha field cropped with maize during the last five years under two different soil management systems for the cover crop sowing, namely conventional tillage and reduced tillagedirect sowing. No significant differences were detected between management strategies and cover crops in terms of soil organic carbon and nitrogen contents, and microbial biomass in the topsoil. Concerning the microbiome, characterized through Next Generation Sequencing methods, this study showed that soil management type was the main factor defining the structure of fungal and bacterial populations. The effect of the leguminous species was smaller, although differences were observed in the composition and frequency of appearance of the different OTUs characterized.

覆盖作物种植（Cover cropping）是一类与再生农业密切相关的耕作实践，其应用强度参差不齐，迄今已有约百年历史。覆盖作物不仅可为经济作物提供多重益处与生态系统服务，还能促进土壤微生物组分的修复，缓解土壤在遭受高强度耕作措施后出现的微生物耗竭问题。本研究针对一块过去五年间持续种植玉米的2公顷田块，设置了基于三种不同豆科物种（Vicia villosa、Vicia sativa及Pisum sativum）的覆盖作物种植试验，并采用两种覆盖作物播种土壤管理模式——常规耕作与少免耕直接播种，分析了相关土壤生物物理特性，以及覆盖作物引入后土壤微生物群落的组成与结构。就表层土壤的有机碳、全氮含量与微生物生物量而言，未观测到不同管理策略与覆盖作物种类间存在显著差异。针对通过下一代测序（Next Generation Sequencing）技术表征的微生物组，本研究显示土壤管理模式是决定真菌与细菌种群结构的核心影响因素；豆科物种的影响相对较弱，但在所表征的不同操作分类单元（Operational Taxonomic Unit，OTU）的组成与出现频率上仍存在差异。