Lin Litao, Jing Xin, Lucas-Borja Manuel Esteban, Shen Congcong, Wang Yugang, Feng Wenting
Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
Front Microbiol. 2022 May 23;13:862245. doi: 10.3389/fmicb.2022.862245. eCollection 2022.
Salinization poses great threats to soil fungal communities that would cause the losses of ecosystems services. Soil fungal communities are composed of different functional guilds such as saprotrophic, symbiotrophic, and pathotrophic fungi, and each guild includes many rare taxa and a few abundant taxa. Despite of low abundance, rare taxa may be crucial in determining the responses of entire soil fungal communities to salinization. However, it remains poorly understood how rare taxa mediate the impacts of soil salinization on soil fungal community structure. Here, we took advantage of a salinity gradient in a desert ecosystem ranging from 0.60 to 31.09 g kg that was created by a 12-year saline-water irrigation and assessed how the rare vs. abundant taxa of soil saprotrophic, symbiotrophic, and pathotrophic fungi respond to soil salinization through changes in the community biodiversity and composition. We found that the rare taxa of soil saprotrophic, symbiotrophic, and pathographic fungi were more sensitive to changes in soil salinity compared to the abundant taxa. In addition, the community composition of rare taxa of the saprotrophic and pathotrophic fungi not the symbiotrophic fungi was positively associated with soil salinity change. However, the symbiotrophic fungi showed greater variations in the species richness along the salinity gradient. These findings highlight the importance to differentiate rare taxa in predicting how the biodiversity and functional groups of soil fungal communities respond to soil salinization.
盐渍化对土壤真菌群落构成了巨大威胁，这会导致生态系统服务功能的丧失。土壤真菌群落由不同的功能类群组成，如腐生真菌、共生真菌和致病真菌，每个类群都包括许多稀有分类单元和少数优势分类单元。尽管稀有分类单元丰度较低，但它们在决定整个土壤真菌群落对盐渍化的响应方面可能至关重要。然而，关于稀有分类单元如何介导土壤盐渍化对土壤真菌群落结构的影响，目前仍知之甚少。在此，我们利用了一个沙漠生态系统中由12年盐水灌溉形成的0.60至31.09 g/kg的盐度梯度，评估了土壤腐生真菌、共生真菌和致病真菌的稀有分类单元与优势分类单元如何通过群落生物多样性和组成的变化来响应土壤盐渍化。我们发现，与优势分类单元相比，土壤腐生真菌、共生真菌和致病真菌的稀有分类单元对土壤盐度变化更为敏感。此外，腐生真菌和致病真菌而非共生真菌的稀有分类单元的群落组成与土壤盐度变化呈正相关。然而，共生真菌沿盐度梯度的物种丰富度变化更大。这些发现凸显了在预测土壤真菌群落的生物多样性和功能群如何响应土壤盐渍化时区分稀有分类单元的重要性。
