Quinteros-Urquieta Carolina, Francois Jean Pierre, Aguilar-Muñoz Polette, Molina Verónica
Programa de Doctorado Interdisciplinario en Ciencias Ambientales, Universidad de Playa Ancha, Avenida Leopoldo Carvallo 270, Playa Ancha, Valparaíso 2340000, Chile.
Departamento de Ciencias y Geografía, Universidad de Playa Ancha, Avenida Leopoldo Carvallo 270, Playa Ancha, Valparaíso 2340000, Chile.
Microorganisms. 2024 Dec 3;12(12):2487. doi: 10.3390/microorganisms12122487.
The Parque Nacional La Campana (PNLC) was recently recognized for its high soil surface microbial richness. Here, we explored the microbial community structure in soil profiles from contrasting facing slopes where sclerophyllous forest (SF) and xerophytic shrubland (XS) develop. Soil physicochemical conditions (dry density, pH, and organic matter C and N isotopic soil signatures) were determined at three depths (5, 10, and 15 cm depths). Amplicon sequencing (16S rRNA and ITS1-5F) and specific quantification (qPCR bacteria, archaea and ammonia-oxidizing archaea, fungi) were used to profile the microbial community. Our results indicate that opposite slopes, with different vegetation types and soil conditions studied potentially explained the spatial variability of the microbial community composition, especially between sites than through soil depth. Discriminative taxa were observed to vary between sites, such as, . nitrososphaera (ammonia-oxidizing archaea) and Sphingomonas, and bacteria associated with Actinobacteria and Bacteroidetes were predominant in SF and XS, respectively. Fungi affiliated with Humicola and Preussia were more abundant in SF, while Cladosporium and Alternaria were in XS. Higher ASV richness was observed in SF compared to XS, for both prokaryotes and fungi. Furthermore, SF showed a higher number of shared ASVs, while XS showed a decrease in unique ASVs in deeper soil layers. In XS, the genus DA101 (Verrucomicrobia) increases with soil depth, reaching higher levels in SF, while Kaistobacter shows the opposite trend. PNLC soils were a reservoir of redundant microbial functions related to biogeochemical cycles, including symbiotic and phytopathogenic fungi. In conclusion, as with the predominant vegetation, the structure and potential function of microbial life in soil profiles were associated with the contrasting the effect of facing slopes as toposequence effects.
拉坎帕纳国家公园（PNLC）最近因其土壤表面微生物丰富度高而受到认可。在此，我们探索了硬叶林（SF）和旱生灌木丛（XS）发育的相反坡面土壤剖面中的微生物群落结构。在三个深度（5厘米、10厘米和15厘米深度）测定了土壤理化条件（干密度、pH值以及有机碳和氮的同位素土壤特征）。采用扩增子测序（16S rRNA和ITS1 - 5F）和特异性定量（qPCR检测细菌、古菌、氨氧化古菌、真菌）来分析微生物群落。我们的结果表明，所研究的具有不同植被类型和土壤条件的相反坡面可能解释了微生物群落组成的空间变异性，尤其是不同地点之间的变异性，而非土壤深度造成的差异。观察到不同地点的判别分类群有所不同，例如，亚硝化球菌属（氨氧化古菌）和鞘氨醇单胞菌属，与放线菌门和拟杆菌门相关的细菌分别在SF和XS中占主导地位。与腐质霉属和普列斯尼亚克氏菌属相关的真菌在SF中更为丰富，而枝孢属和链格孢属在XS中更为丰富。与XS相比，SF中观察到原核生物和真菌的扩增子序列变体（ASV）丰富度更高。此外，SF显示出更多共享的ASV，而XS在较深土壤层中独特ASV数量减少。在XS中，DA101属（疣微菌门）随土壤深度增加，在SF中达到更高水平，而凯斯氏菌属则呈现相反趋势。PNLC土壤是与生物地球化学循环相关的冗余微生物功能的储存库，包括共生真菌和植物致病真菌。总之，与主要植被一样，土壤剖面中微生物生命的结构和潜在功能与作为地形序列效应的相反坡面的影响相关。
