辽西北风沙区不同人工林土壤真菌群落结构及功能特征

[目的]为了揭示土壤真菌群落结构及功能对不同人工林的响应特征和响应机制,评估不同人工林对地下生态系统的影响。[方法]以辽西北风沙区樟子松人工林、油松人工林和杨树人工林为研究对象,对每个样地采用"S"型布点采样,采集0~10 cm表层土壤并进行混合,采用Illumina Miseq高通量测序技术和FUNGuild软件,获取并分析辽西北风沙区不同人工林土壤真菌群落组成与功能特征,并对土壤真菌群落多样性与土壤环境因子进行相关性分析。[结果]表明:杨树人工林能显著增加土壤pH值、土壤可溶性有机碳和速效磷的含量,降低土壤的C/N。该区人工林土壤优势真菌门类群是子囊菌门和担子菌门,优势真菌属类群为Guehomyces、被抱霉属及青霉菌属。NMDS和heatmap分析结果表明,不同人工林土壤真菌群落结构和功能特征差异显著,都可划分为两个聚类,其中,樟子松人工林和油松人工林土壤真菌群落结构和功能的相似性较大,而杨树人工林土壤真菌群落与针叶林土壤真菌群落结构和功能的差异较大。土壤pH、速效磷、DOC和C/N是影响土壤真菌多样性和土壤真菌群落功能的主要因子。[结论]不同人工林对土壤特性及土壤真菌群落的结构和功能特征具有不同的影响,杨树人工林显著提高土壤养分有效性,增加土壤真菌多样性。因此,在辽西北风沙区种植杨树较针叶树能更好地改善土壤。

Studies on Soil Fungal Community Composition and Function Characteristics of Different Plantations of Sandy Area,Northwest Liaoning Province

[Objective]To reveal the response characteristics and mechanism of soil fungal community structure and function to different plantations,and to evaluate the impact of different plantations on the undergroxind ecosystem.[Method]Pinus sylvestris var.mongolica plantation,Pinus tabulifbrmis plantation,and Populus x canadensis plantation in the north wind sand area of western Liaoning province were investigated.For each sampling plot,the type spot sampling method was used to collect the surface soil of 0〜10 cm at multiple points.Illumina Miseq highthroughput sequencing technology and FUN Guild software were applied to obtain and analyze the response characteristics of soil microbial community composition and function in different plantations.Meanwhile,the relationships between soil fungal community diversity,community structure and soil environmental factors were analyzed.[Result]The plantation of Populus x canadensis could significantly increase the soil pH value,soil-dissolved organic carbon and available phosphorus content,and reduce soil C/N ratio.The dominant fungal phyla in these plantations were Ascomycota and Basidiomycota,and the dominant fungal genera were Guehomyces.Mortierella and Penicillium.The results of NMDS and heatmap analysis showed that there were significant differences in the community structure and function of soil fungi among different plantations and the community composition and function could be divided into two clusters.The community structure of soil fungi in Pinus sylvestris var.mongolica,and Pinus tabulifarmis plantations were similar,while the community composition and function in plantation of Populus x canadensis Moench were significantly different from that in coniferous plantations.The soil pH,available phosphorus,dissolved organic carbon and C/N ratio were the main factors affecting soil fungal community diversity and functions・[Conclusion]The effect on soil characteristics and the soil fungal composition and function differs among different plantations.The plantation of Populus x canadensis Moench significantly increases the soil nutrient availability and soil fungal diversity.