To improve our understanding of early microbial colonization of pristine minerals and their group-specific C utilization, we exposed minerals (illite/goethite/quartz) amended with artificial root exudates (ARE, glucose, and citric acid) in grassland soils for a period of 24 weeks. FTIR spectra indicated that mineral-associated ARE were used within the first 2 weeks of exposure and were replaced by other carbohydrates derived from living or dead cells as well as soil-borne C sources transported into the mineralosphere after heavy rain events. Fungi and Gram-positive bacteria incorporated ARE-derived C more rapidly than Gram-negative bacteria. Gram-negative bacteria presumably profited indirectly from the ARE by cross-feeding on mineral-associated necromass of fungi and Gram-positive bacteria. The Gram-negative bacterial phyla Verrucomicrobia, Planctomycetes, Gemmatimonadetes, Armatimonadetes, and Chloroflexi showed a positive correlation with Gram-negative PLFA abundances. After 24 weeks of exposure in the grassland soils, abundances of soil microorganisms in the mineralosphere reached only 3.1% of the population density in soil. In conclusion, both bacteria and fungi slowly colonize new surfaces such as pristine minerals, but quickly assimilate artificial root exudates, creating an active microbial community in the mineralosphere.

为了增进我们对原始矿物质的早期微生物定植及其特定组C利用率的了解，我们在草地土壤中暴露了用人工根系分泌物（ARE，葡萄糖和柠檬酸）修正的矿物质（伊利石/针铁矿/石英）。 24周。FTIR光谱表明，与矿物质有关的ARE在暴露的前两周内被使用，并被暴雨事件后从活细胞或死细胞衍生的其他碳水化合物以及土壤中C来源的碳源替代。真菌和革兰氏阳性细菌掺入ARE衍生的C比革兰氏阴性细菌更快。革兰氏阴性菌大概是通过交叉饲喂与矿物相关的真菌和革兰氏阳性菌坏死而从ARE中间接获利的。革兰氏阴性菌门Verrucomicrobia，Planctomycetes，Gemmatimonadetes，Armatimonadetes和Chloroflexi与革兰氏阴性PLFA含量呈正相关。在草原土壤中接触24周后，矿物层中土壤微生物的丰度仅达到土壤人口密度的3.1％。总之，细菌和真菌都在新表面（例如原始矿物质）上缓慢繁殖，但很快吸收了人工根系分泌物，从而在矿床中形成了活跃的微生物群落。