Short-term response of soil fungal community composition and trophic mode to winter mulch management in Lei bamboo (Phyllostachys praecox) forests

Abstract

Winter mulching is a periodic short-term warming measure commonly used in agroforestry production, that has a fluctuating impact on the soil microenvironment. However, We know little about the response of fungal communities and their trophic patterns to short-term mulching. In this study, soil fungal communities in Lei bamboo (Phyllostachys praecox) forests were explored under a 4-month winter mulching period (from Month 0 to 4). Three kinds of organic compounds that can be fermented to produce similar high temperatures were used as mulch. With the extension of the mulching period, alpha diversity of the three mulching-type treatments followed a similar trend, with the values peaking in Month 1 and then decreasing sharply. Fungal community composition was clustered according to mulching time rather than mulching type. The majority of the soil fungi were Trechispora, Penicillium, and Trichoderma species before mulching, while Archaeorhizomyces became the most abundant genus, followed by Trechispora and Penicillium after mulching. Redundancy analysis strongly suggested that compositional shifts were related to dynamic alterations in the soil microenvironment, mainly soil temperature and the contents of available nutrients. The co-occurrence patterns of the fungal community were different in the three post hoc groups, with variation in keystone taxa and module populations. Wood saprotrophs were the most abundant functional guild before mulching, while soil saprotrophs were increased after mulching. These results indicated that winter mulching resulted a strong interference with soil fungal communities and that the effects of short-term agricultural disturbance on soil biodiversity cannot be ignored.