The conversion of cropland to plantation is important ecological engineering in the Loess Plateau, China. Moreover, the extent of cropland abandonment and fallow is gradually increasing in this area, which probably affects the soil bacterial composition. Therefore, we applied Illumina MiSeq sequencing targeting the V3–V4 region of the 16S rRNA gene to analyze the bacterial community from different land-use types (cropland, plantation, cropland fallow and abandonment). The results showed that the plantation soil had the highest bacterial diversity. Biomarkers that strongly differentiated land-use types were found. The plantation, cropland fallow and abandonment were primarily associated with Proteobacteria, Nitrospirae, Acidobacteria, Firmicutes and Verrucomicrobia. The dominant populations from different land-use types had high similarity at the genus level, but there were still significant differences on the relative abundance of bacteria among some populations. Moreover, Pearson's correlations indicated that soil available phosphorus (SAP), soil available K (SAK) and vegetation biomass were the important factors affecting the bacterial community. These results suggested that bacterial community structure differed among different land-use types, which was closely related to soil environmental factors, such as SAP and SAK.

退耕还林是黄土高原地区重要的生态工程。此外，该地区农田的废弃和休耕程度正在逐渐增加，这可能会影响土壤细菌的组成。因此，我们针对16S rRNA基因的V3-V4区应用了Illumina MiSeq测序，以分析来自不同土地利用类型（农田，种植园，休耕地和废弃地）的细菌群落。结果表明，人工林土壤的细菌多样性最高。发现了高度区分土地利用类型的生物标记。人工林，农田休耕和废弃主要与Proteobacteria，Nitrospirae，Acidobacteria，Fimicutes相关。和Verrucomicrobia。不同土地利用类型的优势种群在属水平上具有高度相似性，但某些种群之间细菌的相对丰度仍然存在显着差异。而且，Pearson的相关性表明，土壤有效磷（SAP），土壤有效钾（SAK）和植被生物量是影响细菌群落的重要因素。这些结果表明，不同土地利用类型之间的细菌群落结构不同，这与土壤环境因素如SAP和SAK密切相关。