Root-centric β diversity reveals functional homogeneity while phylogenetic heterogeneity in a subtropical forest

Root-centric studies have revealed fast taxonomic turnover across root neighborhoods, but how such turnover is accompanied by changes in species functions and phylogeny (i.e. β diversity), which can reflect the degree of community-wide biotic homogenization, remains largely unknown, hindering better inference of below-ground assembly rules, community structuring, and ecosystem processes. We collected 2480 root segments from 625 0–30 cm soil profiles in a subtropical forest in China. Root segments were identified into 143 species with DNA-barcoding with six root morphological and architectural traits measured per species. By using the mean pairwise (Dpw) and mean nearest neighbor distance (Dnn) to quantify species ecological differences, we tested the non-random functional and phylogenetic turnover of root neighborhoods that would lend more support to deterministic over stochastic community assembly processes, examined the distance-decay pattern of β diversity, and finally partitioned β ..., We randomly collected root materials from 625 soil cores (i.e., root neigbourhoods) in a subtropical forest. Species were identified with DNA-barcoding and their morphologies. Soil variables were measued within a distance of 10 cm from the root-sampling core.The spatial distances of soil cores were quantified based on the coordinates of the cores. Species phylogeny was onstructed based on DNA sequence. Species root morphological and archetectural traits were measured with WinRHIZO., These datasets were collected in the Guangdong Heishiding Dynamic Forest Plot in Southern China (2016). Details for each dataset are provided in the README file., # Beta diversity among root neigbourhoods

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In this study, we looked at the functional and phylogenetic turnover rate (e.g., dissimilarity of functional traits and phylogenetic relatedness among species ) of root-centric species among root neighbourhoods (e.g., soil patches where multiple heterospecific roots cooccur) in a subtropical forest in southern China. The study aimed to compare the turnover rate of functions and phylogeny with that of plant taxonomy. Trait dissimilarity among species was quantified based on six root functional traits with species phylogenetic relatedness quantified based on a phylogeny. Multiple abiotic variables were measured at the soil core level such as topographical variables (e.g., elevation) and soil variables (e.g., soil nitrogen and phosphorus content).

## Description of the data and file structure

1. the [Root.trait.data] file is composed of 138 rows and 7 columns. Each row indicates one species named as \"species\", and the remaining rows indicat...