科尔沁沙地樟子松人工林土壤真菌群落结构和功能特征

[Objective]To explore a firm basis for sustainable management of Pinus sylvestris var.mongolica,soil fungal community structure and functional characteristics as well as the driving soil properties were revealed in different stand ages of P.sylvestris plantations in the Horqin Desert.[Method]We sampled the soil of P.sylvestris plantations with young-mature(13 a),half-mature(22 a),nearly-mature(34 a),mature(41 a)and over-mature(55 a),and soil fungal communities were identified by Illumina MiSeq high-throughput sequencing and FUNGuild platform.[Result](1)In the Horqin Desert,922 fungal OTUs were obtained from soil samples of P.sylvestris plantations,and belonged to 254 genera,98 families,67 orders,25 classes,and 14 phyla.Ascomycota and Basidiomycota were predominated,and the dominant genera were Calostoma and Amphinema.(2)With stand aging,the proportion of symbiotic fungi and the dominated functional groups ectomycorrhizal fungi climbed up and then declined,with a minimum in the mature plantations;the proportion of saprophytic fungi and the dominated functional groups undefined saprophytic fungi decreased after a little increase,with a maximum in mature plantations;the distribution of pathotrophic fungi was relatively uniform.(3)With stand aging,soil fungal network showed a differentiated tendency which simplified first and then complicated.The network of nearly-mature plantations was the simplest,and the over-mature plantations was the most complex followed by the mature plantations.(4)Soil organic matter,pH,alkali-hydrolyzable nitrogen and nitrate nitrogen were the most important driving factors for soil fungal community structure.The relative abundance of saprophytic fungi was positively and negatively correlated with soil total phosphorus and pH,respectively(P<0.05),and the relative abundance of saprophytic fungi had a significant positive correlated with soil organic matter(P<0.01).[Conclusion]Stand age and soil properties play a key role in the soil fungal community construction associated with P.sylvestris plantations in the Horqin Desert.From young to nearly-mature plantations,the dominant symbiotic fungi accumulation,which benefit the rapid growth of plantations.In mature and over-mature plantations,the soil fungal community structure is similar,saprophytic fungi are the dominant species,and the soil fungal community network tend to complex and stable,which contribute to the resistance improvement of plantations to changeable environments.This improved information will provide a better understanding of soil fungal functions of P.sylvestris plantations in the Horqin Desert,as well as the forest and soil health from the perspective of soil fungi.