DOI: 10.5061/dryad.sqv9s4nfw
title: Dominant species drive ecosystem multifunctionality under changed precipitation timing in a semi-arid steppe

description: Biodiversity significantly affects ecosystem multifunctionality,
 particularly in the context of changing precipitation patterns. However,
 the relative importance of multiple dimensions of diversity (e.g.,
 taxonomic, functional, and phylogenetic diversity) on ecosystem
 multifunctionality under different precipitation patterns remains unclear.
 In this study, we conducted a seven-year field manipulation precipitation
 experiment in the semi-arid steppe to examine the effects of taxonomic,
 functional, and phylogenetic diversity on total ecosystem
 multifunctionality (EMF), aboveground ecosystem multifunctionality
 (AGEMF), and belowground ecosystem multifunctionality (BGEMF) under
 changed precipitation in different periods. The results showed that
 decreased precipitation in the early (DEP), late (DLP), and entire growing
 season (DP) reduced EMF by 6.5%, 8.4%, and 11.6%, respectively, whereas
 increased precipitation in different periods had no effect on EMF. DEP,
 DLP, and DP decreased AGEMF by 10.0%, 9.7%, and 19.0%, respectively. In
 contrast, increased precipitation in the early (IEP) and entire (IP)
 growing season enhanced AGEMF by 5.1% and 6.9%, respectively. However,
 increased precipitation during the late growing season (ILP) did not
 affect AGEMF. DLP and DP decreased BGEMF by 13.3% and 11.2%, respectively,
 whereas other precipitation treatments had no effect on BGEMF. Species
 dominance was the major driver of AGEMF and BGEMF under precipitation
 decreases while soil moisture was the best predictor of AGEMF under
 precipitation increases. In contrast, functional and phylogenetic
 diversity had no effect on ecosystem multifunctionality. The greater
 sensitivity of EMF, AGEMF, and BGEMF to precipitation decreases than to
 precipitation increases indicates an asymmetric response of ecosystem
 multifunctionality to precipitation changes, highlighting that decreased
 precipitation during the late growing season weakens ecosystem
 multifunctionality by reducing the roles of dominant species in the
 semi-arid steppe. The findings are crucial for informing effective
 grassland management policies and maintaining stable ecosystem provisions.
description: # Dominant species drive ecosystem multifunctionality under changed
 precipitation timing in a semi-arid steppe Dataset DOI:
 [10.5061/dryad.sqv9s4nfw](10.5061/dryad.sqv9s4nfw) ## Description of the
 data and file structure Dominant species drive ecosystem
 multifunctionality under changed precipitation timing in a semi-arid
 steppe: Open Source Data ### Files and variables | Variable | **Full
 name** | **Description** | \*\*Units \*\* | | :-------- |
 :--------------------------------------- |
 :---------------------------------------------------------------------------------------------------------- | :------------------------------------------------------------------------- | | Treat | Treat | Experimental treatment group(see treatment codes below)  | n/a | | PD | Faith’PD | Phylogenetic diversity: sum of branch lengths in the phylogenetic tree spanning all species in a community | n/a (higher values indicate greater evolutionary divergence among species) | | SR | Species richness | Taxonomic diversity: total number of species recorded per plot | `species m⁻²` | | Dominance | Dominance\_D | Taxonomic diversity: the relative abundance of dominant species | n/a (range: 0–1) | | PSR | Phylogenetic species richness | Phylogenetic diversity: phylogenetic diversity after controlling for species richness | n/a (0-20) | | CWMtraits | Community weighted mean (CWM) trait |  Functional diversity: CWM traits (n=5) were PCA-reduced to identify key functional axes | n/a (first principal component (scaled)) | | FDis | Functional dispersion |  Functional diversity: the degree of dispersion of functional traits in multi-dimensional space | n/a (range: 0–3) | | EMF | Total ecosystem multifunctionality | Total ecosystem multifunctionality was calculated as the mean value of 13 ecosystem functional metrics | n/a (calculated as mean of normalized functions) | | AGEMF | Aboveground ecosystem multifunctionality | Aboveground ecosystem multifunctionality was calculated as the mean value of 6 ecosystem functional metrics | n/a (calculated as mean of normalized functions) | | BGEMF | Belowground ecosystem multifunctionality | Belowground ecosystem multifunctionality was calculated as the mean value of 7 ecosystem functional metrics | n/a (calculated as mean of normalized functions) | | SM | Soil moisture | soil moisture | V/V% | | Treatment Codes | | | :-------------- | :-------------------------------------------------------------------------------------------------- | | C | control | | DEP | precipitation in the early growing season (from mid-April to the end of June) was decreased by 60% | | DLP | precipitation in the late growing season (from early July to mid-September) was decreased by 60% | | DP | precipitation in the entire growing season (from mid-April to mid-September) was decreased by 60% | | IEP | precipitation in the early growing season (from mid-April to the end of June) was  increased by 60% | | ILP | precipitation in the late growing season (from early July to mid-September) was  increased by 60% | | IP | precipitation in the entire growing season (from mid-April to mid-September) was  increased by 60% | ## Code/software We analyzed PD, SR, Dominance, PSR, CWMtraits, FDis, EMF,AGEMF,  BGEMF, and SM, using one-way variance analysis (ANOVA), and the LSD multiple comparisons was used to evaluate differences among precipitation treatments. In addition, linear regression analysis was used to test the influences of PD, SR, Dominance, PSR, CWMtraits, FDis, EMF,AGEMF,  BGEMF, and SM. R is required to run *Code_for_Dominant species drive ecosystem multifunctionality under changed precipitation timing in a semi-arid steppe*; the script was created using version 4.2.2.Annotations are provided throughout the script through 1) library loading, 2) dataset loading and cleaning, 3) analyses, and 4) figure creation. **Version changes** July 8, 2025: Corrected an issue with the data range by aligning it with the original paper's dataset.