Chen Jian, Shi Zuomin, Liu Shun, Zhang Miaomiao, Cao Xiangwen, Chen Miao, Xu Gexi, Xing Hongshuang, Li Feifan, Feng Qiuhong
Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing 100091, China.
Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County 623100, China.
J Fungi (Basel). 2022 Jul 30;8(8):807. doi: 10.3390/jof8080807.
Soil fungi play an integral and essential role in maintaining soil ecosystem functions. The understanding of altitude variations and their drivers of soil fungal community composition and diversity remains relatively unclear. Mountains provide an open, natural platform for studying how the soil fungal community responds to climatic variability at a short altitude distance. Using the Illumina MiSeq high-throughput sequencing technique, we examined soil fungal community composition and diversity among seven vegetation types (dry valley shrub, valley-mountain ecotone broadleaved mixed forest, subalpine broadleaved mixed forest, subalpine coniferous-broadleaved mixed forest, subalpine coniferous forest, alpine shrub meadow, alpine meadow) along a 2582 m altitude gradient in the alpine-gorge region on the eastern Qinghai-Tibetan Plateau. Ascomycota (47.72%), Basidiomycota (36.58%), and Mortierellomycota (12.14%) were the top three soil fungal dominant phyla in all samples. Soil fungal community composition differed significantly among the seven vegetation types along altitude gradients. The α-diversity of soil total fungi and symbiotic fungi had a distinct hollow pattern, while saprophytic fungi and pathogenic fungi showed no obvious pattern along altitude gradients. The β-diversity of soil total fungi, symbiotic fungi, saprophytic fungi, and pathogenic fungi was derived mainly from species turnover processes and exhibited a significant altitude distance-decay pattern. Soil properties explained 31.27-34.91% of variation in soil fungal (total and trophic modes) community composition along altitude gradients, and the effects of soil nutrients on fungal community composition varied by trophic modes. Soil pH was the main factor affecting α-diversity of soil fungi along altitude gradients. The β-diversity and turnover components of soil total fungi and saprophytic fungi were affected by soil properties and geographic distance, while those of symbiotic fungi and pathogenic fungi were affected only by soil properties. This study deepens our knowledge regarding altitude variations and their drivers of soil fungal community composition and diversity, and confirms that the effects of soil properties on soil fungal community composition and diversity vary by trophic modes along altitude gradients in the alpine-gorge region.
土壤真菌在维持土壤生态系统功能方面发挥着不可或缺且至关重要的作用。关于海拔变化及其对土壤真菌群落组成和多样性的驱动因素的理解仍相对不清楚。山脉为研究土壤真菌群落在短海拔距离内如何响应气候变异性提供了一个开放的自然平台。利用Illumina MiSeq高通量测序技术，我们研究了青藏高原东部高山峡谷地区沿2582米海拔梯度的七种植被类型（干谷灌木、谷山交错带阔叶混交林、亚高山阔叶混交林、亚高山针叶阔叶混交林、亚高山针叶林、高山灌丛草甸、高山草甸）之间的土壤真菌群落组成和多样性。子囊菌门（47.72%）、担子菌门（36.58%）和被孢霉门（12.14%）是所有样本中排名前三的土壤真菌优势门类。沿海拔梯度，七种植被类型之间的土壤真菌群落组成存在显著差异。土壤总真菌和共生真菌的α多样性呈现出明显的空心模式，而腐生真菌和致病真菌沿海拔梯度未表现出明显模式。土壤总真菌、共生真菌、腐生真菌和致病真菌的β多样性主要源于物种更替过程，并呈现出显著的海拔距离衰减模式。土壤性质解释了沿海拔梯度土壤真菌（总真菌和营养模式）群落组成变异的31.27 - 34.91%，且土壤养分对真菌群落组成的影响因营养模式而异。土壤pH是沿海拔梯度影响土壤真菌α多样性的主要因素。土壤总真菌和腐生真菌的β多样性及更替组分受土壤性质和地理距离影响，而共生真菌和致病真菌的β多样性及更替组分仅受土壤性质影响。本研究加深了我们对海拔变化及其对土壤真菌群落组成和多样性驱动因素的认识，并证实了在高山峡谷地区，土壤性质对土壤真菌群落组成和多样性的影响沿海拔梯度因营养模式而异。
