DOI: 10.5061/dryad.63xsj3v86
title: Plant species composition and key-species abundance drive ecosystem multifunctionality

description: Global biodiversity loss has generated great interest in the role of plant
 communities in driving ecosystem functions. There is limited understanding
 of how soil properties, plant richness, and plant community composition
 interact to affect ecosystem multifunctionality. We conducted a
 constructed-ecosystem experiment by simultaneously manipulating soil
 origin (i.e., fertile farmland soil and relatively infertile bare land
 soil), plant richness, and community composition (one-species monoculture,
 and all possible two-, three-, and four-species combinations of five
 plants) to evaluate their influence on ecosystem multifunctionality
 related to the accumulation of biomass, carbon (C) and nitrogen (N) in
 plants, greenhouse gas emissions, soil nutrients, soil N fixation, and
 mineralization of N and phosphorus (P). We found that ecosystem
 multifunctionality was significantly affected by soil origin, plant
 community composition, and the community-weighted mean (CWM) of plant
 biomass, but not by plant richness. We grouped the community composition
 into the N-fixing group (including N-fixing plants) and the non-N-fixing
 group (excluding N-fixing plants). The N-fixing plant group exhibited
 significantly higher multifunctionality than the non-N-fixing species
 group in both soil origins. For bare land soil, multifunctionality
 increased with the increasing relative abundance and biomass ratio of
 Albizia julibrissin (N-fixing species) in communities, but decreased with
 the biomass ratio of Platycladus orientalis (non-N-fixing species). For
 farmland soil, multifunctionality increased with the abundance of Toona
 sinensis (non-N-fixing species) and the biomass ratio of Albizia
 julibrissin, but decreased with the abundance and biomass ratio of Morus
 alba (non-N-fixing species). These results indicate that the key-species
 determining ecosystem multifunctionality vary under different soil
 conditions. Synthesis and applications. We propose that plant community
 composition and the relative abundance and biomass ratio of key-species
 drive ecosystem multifunctionality. We suggest that selecting the
 appropriate plant combination under different soil conditions should be
 emphasized in ecological restoration projects. Our study highlights the
 differentiated roles of key-species on ecosystem functions under different
 resource conditions. The N fixation in general plays a crucial role in
 driving ecosystem multifunctionality and the N-fixing plants can serve as
 restoration tools in nutrient-poor degraded lands.
description: We conducted a
 constructed-ecosystem experiment by simultaneously manipulating soil
 origin (i.e., fertile farmland soil and infertile bare land soil), plant
 richness (from one to four species), and composition (five single species,
 all possible two-, three-, and four- species combinations of the five
 species). The goal was to assess how each manipulation drives ecosystem
 multifunctionality related to C and N accumulation, greenhouse gas
 emissions, soil nutrients, soil N-fixing, and mineralization rates of N
 and P.
description: # Plant species composition and key-species abundance drive ecosystem
 multifunctionality
 [https://doi.org/10.5061/dryad.63xsj3v86](https://doi.org/10.5061/dryad.63xsj3v86) We conducted a constructed-ecosystem experiment by simultaneously manipulating soil origin (i.e., fertile farmland soil and infertile bare land soil), plant richness (from one to four species) and composition (five single species, and all possible two-, three-, and four- species combinations of the five species) to evaluate their importance for driving multiple ecosystem functions related to accumulation of biomass, carbon (C) and nitrogen (N) in plants, greenhouse gas emissions, soil nutrients, soil N fixation, and mineralization of N and phosphorus (P). The constructed-ecosystem experiment was conducted in an experimental field of Wuhan Botanical Garden. We used square PVC pots with a bottom inner area of 19 cm, upper area of 25 cm, height of 16 cm, and small holes in the bottom. Five plant species, i.e., Albizia julibrissin (AJ), Toona sinensis (TS), Morus alba (MA), Platycladus orientalis (PO), and Pinus tabuliformis (PT), were selected in the experiment. The five species are typical indigenous plants in the study region, which can form communities together in abandoned farmlands and bare lands. There were 30 plant treatments in each soil origin: one-species treatments for each species (AJ, TS, MA, PO, and PT), all possible two-species combination treatments (AJ+TS, AJ+MA, AJ+PO, AJ+PT, TS+MA, TS+PO, TS+PT, MA+PO, MA+PT, and PO+PT), all possible three-species combination treatments (AJ+TS+MA, AJ+TS+PO, AJ+TS+PT, AJ+MA+PO, AJ+MA+PT, TS+MA+PO, TS+MA+PT, TS+PO+PT, MA+PO+PT, and AJ+PO+PT), and all possible four-species combination treatments (AJ+TS+MA+PO, AJ+TS+MA+PT, TS+MA+PO+PT, AJ+MA+PO+PT, and AJ+TS+PO+PT). In addition, a blank control (i.e., unplanted) was set for each soil origin. Totally, 248 constructed-ecosystems, i.e., 2 soil origins × 31 treatments (plant treatments + unplanted) × 4 replicates, were established in our experiment. Ecosystem multifunctionality index was calculated using the method of Byrnes et al. (2014) and Maestre et al. (2012a). Ecosystem multifunctionality was evaluated based on 17 ecosystem function variables, including plant biomass, plant N stock, plant C stock, CO2 emission, CH4 emission, N2O emission, soil net N mineralization rate, soil net P mineralization rate, soil N-fixation rate, soil microbial biomass, MBC, MBN, and the concentrations of soil organic C, soil total N, NO3--N, NH4+-N, and available P. DATA-SPECIFIC INFORMATION FOR: data1004.csv 1\. Number of variables: 40 2\. Number of cases/rows: 240 3\. Variable List: * number : Serial number of the pot experiment * composition: composition * soiltype: soil type * sprichness: plant species richness * spcomposition: plant species composition * block: spatial block * Nfixingtype: N fixing type * leavetype: leaf type * multifunctionality index: ecosystem multifunctionality index * bacteriabiomass: bacteria biomass based on PLFA. * Fungibiomass: Fungi biomass based on PLFA. * Amfungibiomass: Amfungi biomass based on PLFA. * ratioGG: The ratio of gram-positive to Gram-negative bacteria. * ratioBF: The ratio of bacteria to fungi * Total_microbial_biomass: Total microbial biomass based on PLFA. * albizia_relative_abundance: Albizia relative abundance in each of the 240 POTS. * toona_relative_abundance: Toona relative abundance in each of the 240 POTS. * morus_relative_abundance: Morus relative abundance in each of the 240 POTS. * platycladus_relative_abundance: Platycladus relative abundance in each of the 240 POTS. * pinus_relative_abundance: Pinus relative abundance in each of the 240 POTS. * albizia_relative_biomass  : Albizia relative biomass in each of the 240 POTS. * toona_relative_biomass: Toona relative biomass in each of the 240 POTS. * morus_relative_biomass: Morus relative biomass in each of the 240 POTS. * platycladus_relative_biomass: Platycladus relative biomass in each of the 240 POTS. * pinus_relative_biomass: Pinus relative biomass in each of the 240 POTS. * TN: Soil total nitrogen * TOC: Soil organ carbon * ARA: soil N-fixation rate * NO3: Soil NO3--N * NH4: Soil NH4+-N * AP:  Soil available phosphorus  * Nmin: Soil net N mineralization rate * Pmin: soil net P mineralization rate * MSC: Soil microbial biomass carbon * MN: Soil microbial biomass nitrogen * plantbiomass：Plant biomass * Cstock： Plant carbon stock * Nstock： Plant nitrogen stock * CWMbiomass：community-weighted mean (CWM) of plant biomass * M：Ecosystem multifunctionality --- All statistical analyses were performed using R (4.3.0).