Technology Lnnovation Center for Land Engineering and Human Seutlements, Xi'an Jiaotong University, Xi'an, 713599, China.
Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an, 710054, China.
Sci Rep. 2024 Sep 11;14(1):21265. doi: 10.1038/s41598-024-71927-w.
The ecological function of biological crusts in arid and semi-arid areas is of great importance. Bacteria, as a crucial microbial group in biological crusts, play a key role in the formation, nutrient cycling, and regulation of these crusts. However, the succession of biological crusts and the diversity of bacterial communities, along with key environmental factors in the Loess Plateau's hilly and gully areas, remain unclear. This study investigated soil bacterial abundance and diversity in bare soil (BS), alga-lichen mixed crust (MC), and alga-lichen mixed crust subsoil (MCS) using high-throughput sequencing methods. It explored the relationship between the bacterial community in biological crusts and key environmental factors. The results indicated that the Chao1, Shannon index, and phylogenetic diversity of bacteria significantly increased with the succession of biological crusts. There were notable differences in the community composition and structure of bacteria at different stages of crust development, with Rubrobacteria and Cyanobacteriia dominating in MCS. Effective phosphorus, available potassium, nitrogen, pH, and total organic carbon were identified as key environmental factors affecting soil bacterial communities. In summary, the succession of biological crusts alters soil physicochemical characteristics and creates different ecological niches for bacterial communities. Soil nutrients and pH play a crucial role in the selection of bacterial species and the shaping of bacterial communities in the Loess Plateau's hilly and gully areas.
生物结皮在干旱半干旱地区具有重要的生态功能。细菌作为生物结皮中的关键微生物群，在结皮的形成、养分循环和调节中起着关键作用。然而，黄土高原丘陵沟壑区生物结皮的演替过程、细菌群落的多样性以及关键环境因子仍然不清楚。本研究采用高通量测序方法，研究了裸土（BS）、藻菌混合结皮（MC）和藻菌混合结皮下层土（MCS）中的土壤细菌丰度和多样性，探讨了生物结皮中细菌群落与关键环境因子的关系。结果表明，细菌的 Chao1、Shannon 指数和系统发育多样性随着生物结皮的演替而显著增加。在结皮发育的不同阶段，细菌的群落组成和结构存在显著差异，Rubrobacteria 和 Cyanobacteriia 是 MCS 的优势菌群。有效磷、速效钾、氮、pH 和总有机碳被确定为影响土壤细菌群落的关键环境因子。综上所述，生物结皮的演替改变了土壤理化性质，为细菌群落创造了不同的生态位。土壤养分和 pH 值在黄土高原丘陵沟壑区细菌物种的选择和群落的形成中起着关键作用。
