DOI: 10.5061/dryad.fttdz08zc
title: Changes in nitrogen and phosphorus availability driven by secondary succession in temperate forests shape soil fungal communities and function

description: Soil fungal community plays an important role in forest ecosystems, and
 forest secondary succession is a crucial driver of soil fungal community.
 However, the driving factors of fungal community and function during
 temperate forest succession and their potential impact on succession
 processes are poorly understood. In this study, we investigated the
 dynamics of the soil fungal community in three temperate forest secondary
 successional stages (shrublands, coniferous forests, and deciduous
 broadleaf forests) using high-throughput DNA sequencing coupled with
 functional prediction via the FUNGuild database. We found that fungal
 community richness, α-diversity, and evenness decreased significantly
 during the succession process. Soil available phosphorus and nitrate
 nitrogen decreased significantly after initial succession occurred, and
 redundancy analysis showed that both were significant predictors of soil
 fungal community structure. Among functional groups, fungal saprotrophs as
 well as pathotrophs represented by plant pathogens were significantly
 enriched in the early-successional stage, while fungal symbiotrophs
 represented by ectomycorrhiza were significantly increased in the
 late-successional stage. The abundance of both saprotroph and pathotroph
 fungal guilds was positively correlated with soil nitrate nitrogen and
 available phosphorus content. Ectomycorrhizal fungi were negatively
 correlated with nitrate nitrogen and available phosphorus content and
 positively correlated with ammonium nitrogen content. These results
 indicated that the dynamics of fungal community and function reflected the
 changes in nitrogen and phosphorus availability caused by the secondary
 succession of temperate forests. The fungal plant pathogen accumulated in
 the early-successional stage and ectomycorrhizal fungi accumulated in the
 late-successional stage may have a potential role in promoting forest
 succession. These findings contribute to a better understanding of the
 response of soil fungal communities to the secondary forest succession
 process and highlight the importance of fungal communities during
 temperate forest succession.
description: The soil samples were
 collected on 28 April 2021. There were three monodominant forest stands
 per forest type, each with a size of 100 × 100 m. Five individuals with
 similar diameter at breast high were chosen from each plot. Three soil
 subsamples were collected at a depth of 0–10 cm after litter removal,
 observing 1 m distance from the central tree in three directions at 120°
 angles. All five individual subsamples were homogenized to a single sample
 (Qu et al.,
 2020). Care was taken
 during tree selection to maintain at least a 10 m distance from non-target
 tree species, and each targeted tree was located farther than 20 m from
 the forest edge. A distance of at least 10 m was maintained between
 sampled trees to ensure spatial independence.
 All samples were put on ice
 and transported back to the laboratory. After removing impurities (stones,
 roots), each sample was divided into three subsamples. (1) One subsample
 was immediately air-dried for determining soil pH, TN, total carbon (TC),
 total phosphorus (TP), total potassium (TK), soil organic carbon (SOC),
 available phosphorus (AP), and available potassium (AK). (2) A -20 ℃
 storage subsample was used to analyze nitrate nitrogen
 (NO<sub>3</sub><sup>−</sup>-N) and
 ammonium nitrogen
 (NH<sub>4</sub><sup>+</sup>-N)
 within 2 weeks. (3) A -80 ℃ storage subsample was used
 to extract DNA.