DOI: 10.5061/dryad.k0p2ngfj4
title: Functional traits and phylogenetic structure based on root neighborhoods shape the mechanisms of species coexistence in underground communities

description: Roots exhibit a wide range of morphological diversity and symbiotic
 relationships, which makes it challenging to find general patterns among
 different taxa under different ecological conditions. Competitive
 exclusion and environmental filtering can drive species coexistence and
 diversity maintenance mechanisms. However, it remains to be seen how these
 two mechanisms shape the functional characteristics and phylogenetic
 structure of root neighborhoods, and this lack of information hinders our
 understanding of the processes that build subterranean communities and
 maintain diversity. We randomly selected 675 root clusters from 207 soil
 samples along a latitudinal gradient in the northeastern Qinghai-Tibet
 Plateau, China. We focused on eight root functional traits of 110
 herbaceous species and analyzed root neighbors’ functional traits and
 phylogenetic structure concerning environmental factors. The root system’s
 phylogenetic structure and functional characteristics varied dramatically
 along the latitudinal gradient. First, the phylogenetic structure changed
 at a latitude of 35.2°N, diverging at a low latitude of 33.06°N and
 aggregating at a high latitude of 37.61°N. Second, root neighborhood
 functional trait aggregation was prevalent in individual root traits (72 %
 of traits). Functional divergence (28 % of traits) appeared to be
 associated with changes in environmental factors, showing a
 multidimensional adaptive synthesis. While environmental filtering can
 drive ecological niche differentiation of species to reduce competition,
 alternative rooting strategies may be equally important to promote
 resource use and species coexistence in the rooted neighborhood.
description: # Functional traits and phylogenetic structure based on root neighborhoods
 shape the mechanisms of species coexistence in underground communities
 [https://doi.org/10.5061/dryad.k0p2ngfj4](https://doi.org/10.5061/dryad.k0p2ngfj4) ## Description of the data and file structure Data Description The data in this study include data on the functional traits of herbaceous plant roots, environmental factor data, species diversity data, phylogenetic data, and mycorrhizal fungi data. They can be accessed and used at any time. Data files include: ## CWM.csv This file shows the standardised effect sizes for the weighted characteristic means (CWM) of root neighbourhood traits at different latitudes. | variables | units | description | | :-------- | :---- | :----------------------------------- | | lat | ° | Latitude value of the sampling point | | RDMC | | Root dry matter content | | RNC | | Root total nitrogen content | | RPC | | Root total phosphorus content | | RCC | | Root organic carbon content | | RTD | | Root tissue density | | SRL | | Specific root length | | AD | | Root diameter | | SRA | | Root-specific surface area | ## CWV.csv This file shows the standardised effect sizes of the weighted characteristic variance (CWV) of root neighbourhood traits at different latitudes. | variables | units | description | | :-------- | :---- | :----------------------------------- | | lat | ° | Latitude value of the sampling point | | RDMC | | Root dry matter content | | RNC | | Root total nitrogen content | | RPC | | Root total phosphorus content | | RCC | | Root organic carbon content | | RTD | | Root tissue density | | SRL | | Specific root length | | AD | | Root diameter | | SRA | | Root-specific surface area | ## env2.txt This file shows data on environmental and climatic factor factors at different sampling points. | variables | units | description | | :----------- | :---- | :------------------------------ | | Sample point | | Sampling point information | | SWC | % | Soil water content | | EC | μS/cm | Electrical conductivity of soil | | pH | | pH of soil | | STN | g/kg | Soil total nitrogen content | | STP | g/kg | Soil total phosphorus content | | SOC | g/kg | Soil organic carbon content | | MAP | mm | Mean annual precipitation | | MAT | ℃ | Mean annual temperature | | :-- | :- | :---------------------- | | ALT | m | Altitude | | :-- | :- | :------- | ## environmental factor.xlsx This file contains environmental and climatic factor data, species richness data, phylogenetic α-diversity data and the standardised effect size of the species' mean pairwise distance for each sampling site. | variables | units | description | | :----------- | :---- | :-------------------------------------------------------------- | | Sample point | | Sampling point information | | SWC | % | Soil water content | | EC | μS/cm | Electrical conductivity of soil | | pH | | pH of soil | | STN | g/kg | Soil total nitrogen content | | STP | g/kg | Soil total phosphorus content | | SOC | g/kg | Soil organic carbon content | | MAP | mm | Mean annual precipitation | | MAT | ℃ | Mean annual temperature | | ALT | m | Altitude | | LAT | ° | Latitude information for sampling points | | SR | | Mean species richness of sampling sites | | PD | | Mean phylogenetic α-diversity of sampling sites | | SESMPD | | standardised effect size of the species' mean pairwise distance | ## Fig2.csv This data represents the results of the SESMPD calculations. | variables | units | description | | :------------ | :---- | :---------------------------------------- | | ntaxa | | Number of categorical units in the sample | | mpd.obs | | Observed mean pairwise distance | | mpd.rand.mean | | Mean of randomized MPD | | mpd.rand.sd | | Standard deviation of randomized MPD | | mpd.obs.rank | | Rank of observed MPD in randomizations | | mpd.obs.z | | Z-score of observed MPD | | mpd.obs.p | | P-value of observed MPD | | runs | | Number of randomisation runs | ## Fig3.csv This data includes species richness, phylogenetic diversity, soil total nitrogen content, mean annual temperature, standardised values of SESMPD, as well as soil type and vegetation type for each sampling site. | variables | units | description | | :-------------------- | :---- | :-------------------------------------------------------------- | | Sample point | | Sampling point information | | Speciesrichness | | Standardised values of species richness | | Phylogeneticdiversity | | Standardised values for phylogenetic diversity | | STN | | Standardised value of total soil nitrogen content | | Meanannualtemperature | | Standardised values of mean annual temperatures | | SESMPD | | standardized effect size of the species’ mean pairwise distance | | Soiltype | | Soil type at the sampling site | | Vegetationtype | | Vegetation type of the sampling site | | :------------- | :- | :----------------------------------- | ## FigS6.csv This data shows the relative incidence of functional trait clustering in the root zone assessed on the basis of species mean trait values CWV. | variables | units | description | | :-------- | :---- | :----------------------------------------------------------------------------------------------------------------------------- | | sample | | Different traits of species | | val | | The relative incidence of functional trait clustering in the root zone assessed on the basis of species mean trait values CWV. | | con | | Species Mean Trait Value CWV Clustered or Overdispersed | ## FigS8.csv This data shows the magnitude of environmental and climatic factors, functional traits, species richness, genealogical diversity and SESMPD standardised values. | variables | units | description | | :----------- | :---- | :-------------------------------------------------------------- | | Sample point | | Sampling point information | | STN | | Standardised value of total soil nitrogen content | | SOC | | Standardised values for soil organic carbon content | | MAT | | Standardised values of mean annual temperatures | | MAP | | Standardised value of average annual precipitation | | ALT | | Standardised values for altitude | | SR | | Standardised values of species richness | | PD | | Standardised values for phylogenetic diversity | | SESMPD | | standardized effect size of the species’ mean pairwise distance | | RNC | | Standardised values for root total nitrogen content | | RTD | | Standardised values for root tissue density | | SRL | | Standardised values for specific root length | | AD | | Standardised values for root diameter | | LAT | | Standardised values for latitude | | :-- | :- | :------------------------------- | ## lat.csv This data shows information about the presence of different plants at different latitudes. | variables | units | description | | :-------- | :---- | :---------------------------------------------- | | ID | | Name of the plant | | Type | | Five different latitude zones | | Lat | | Latitudinal information on species distribution | ## mapping.csv This data shows the distribution of sample plots for each species and the species' order. | variables | units | description | | :------------- | :---- | :---------------------------- | | Species number | | Ranking of species | | ID | | Name of the species | | Location | | Place of belonging of species | | Group | | Order of the species | | Abundance | | Abundance of species | ## rlq$co.txt This data shows the results of RLQ analyses of plant functional traits. | variables | units | description | | :-------- | :---- | :--------------------------------------------- | | name | | Abbreviation of plant trait names | | group | | Classification of different traits in plants | | Axis1 | | First axis coordinate values for  RLQ analysis | | Axis2 | | Second axis coordinate values for RLQ analysis | ## rlq$li.txt This data shows the results of the RLQ analyses for environmental factors. | variables | units | description | | :-------- | :---- | :------------------------------------------------ | | name | | Abbreviations for different environmental factors | | group | | Classification of different environmental factors | | Axis1 | | First axis coordinate values for  RLQ analysis | | Axis2 | | Second axis coordinate values for RLQ analysis | ## spe.txt This data shows the plant community species-sample matrix, recording the abundance of different plant species in each sampling unit. Each row represents one sample unit with identifiers in the format Q1, M1, H1, L1, J1, G1, Y1, etc. First column: sample identifier. Subsequent columns: Latin name of the plant species, the number in the cell indicates the abundance of the species in the corresponding sampling unit, 0 means none. ## trait.xlsx This data shows the mean values of root traits of different plants. | variables | units | description | | :----------- | :---- | :---------------------------- | | Species name | | Name of the species | | Croot | g/kg | Root organic carbon content | | Proot | g/kg | Root total phosphorus content | | Nroot | g/kg | Root total nitrogen content | | AD | mm | Root diameter | ## trait2.txt This data shows the mean values of root traits of different plants. | variables | units | description | | :----------- | :---- | :---------------------------- | | Species name | | Name of the species | | PH | cm | Plant heights | | RCC | g/kg | Root organic carbon content | | RPC | g/kg | Root total phosphorus content | | RNC | g/kg | Root total nitrogen content | | AD | mm | Root diameter | | RTD | | Root tissue density | | SRL | m/g | Specific root length | | SRA | cm²/g | Root-specific surface area | ## tree2.tre This is a phylogenetic tree file for constructing and plotting phylogenetic trees.