DataSheet_1_Intraspecific variation in fine-root traits is larger than in aboveground traits in European herbaceous species regardless of drought.docx

Differences within species (Intraspecific trait variation - ITV) contribute substantially to overall trait variability and environmental harshness can reduce among-species variation. While aboveground traits have received considerable attention, knowledge about ITV in fine-root traits and how it differs from ITV in aboveground traits remains limited. This study examined the partitioning of trait variation aboveground and fine-root traits in 52 European herbaceous species and how such proportions change in response to drought, offering valuable insights for accurate functional species characterization and inter-species comparisons. We studied seven morphological aboveground and fine-root traits under drought and well-watered conditions in a greenhouse experiment. Linear mixed effect models and permutational multivariate analysis of variance (PERMANOVA) were employed to decompose trait variation, ensuring the robustness of our results. We also calculated variance partitioning for the combination of aboveground traits and the combination of fine-root traits, as well as pairs of analogous leaf and fine-root traits (i.e., traits that fulfill similar functions) for each treatment (control and drought). Among-species trait differences explained a greater proportion of overall variance than within-species variation, except for root dry matter content (RDMC). Height and leaf area stood out, with species’ identity accounting for 87-90% of total trait variation. Drought had no significant effect on the proportions of variation in any of the traits. However, the combination of fine-root traits exhibited higher intraspecific variability (44-44%) than aboveground traits (19-21%) under both drought and control. Analogous root traits also showed higher ITV (51-50%) than analogous leaf traits (27-31%). Our findings highlight substantial within-species variation and the nuanced responses of fine-root traits, particularly RDMC, suggesting root traits’ flexibility to soil heterogeneity that fosters less differentiation among species. Among-species trait differences, especially aboveground, may underscore distinct strategies and competitive abilities for resource acquisition and utilization. This study contributes to elucidate the mechanisms underlying the multifunctionality of the above- and belowground plants compartments.</p

Trait and biomass data from plants grown in pots by themselves, monoculture, and mixture

The data file contains data on shoot biomass, root biomass, average leaf area, average root diameter, specific leaf area, specific root length, and root to shoot ratios for 15 species. Traits were collected on plants grown alone, in monoculture, and in mixture

Supplement 1. Data about seed dispersal distances and related traits for 576 plant species used in the analyses, and references for data sources.

<h2>File List</h2><div> <p><a href="DispersalDistanceData.csv">DispersalDistanceData.csv</a> (Md5: 9f51b823e51b7570a42a832bed1fbf07)</p> </div><h2>Description</h2><div> <p>DispersalDistanceData.csv – Data about seed dispersal distances and related traits for 576 plant species. For some species dispersal distance data is available for different dispersal syndromes and thus 600 data points are included. Missing values are denoted by empty cells. 601 rows (with headers), 22 columns, separator "," , decimal ".".</p> <p>Columns are as follows:</p> <blockquote> <p><b>Species</b>: accepted binomial name (without authorship) of a species, validated using Taxonstand (Cayuela et al. 2012) library </p> <p><b>Original</b>: binomial name of a species in a referenced study if different from accepted binomial name</p> <p><b>Genus</b>: taxonomic genus of a species</p> <p><b>Family</b>: taxonomic family of a species, obtained using Taxonstand (Cayuela et al. 2012) library</p> <p><b>Order</b>: taxonomic order of a species, following APG III for angiosperms (The Angiosperm Phylogeny Group 2009) and Christenhuzs and others (2011) for gymnosperms</p> <p><b>Dispersal_syndrome</b>: species’ dispersal syndrome corresponding to the dispersal distance data, derived from the referenced study, categories include ‘animal’, ‘ant’, ‘ballistic’, ‘wind (none)’, ‘wind (special)’</p> <p><b>Growth_form</b>: growth form data derived from the referenced study or databases LEDA (Kleyer et al. 2008) and PLANTS (USDA and NRCS 2011), categories include ‘herb’, ‘shrub’, ‘tree’</p> <p><b>Seed_weight_(mg)</b>: seed mass (mg) data derived from the referenced study or Seed Information Database (Royal Botanic Gardens Kew 2008)</p> <p><b>Seed_release_height_(m)</b>: seed releasing height (m) data derived from the referenced study or LEDA (Kleyer et al. 2008) database</p> <p><b>Seed_terminal_velocity_(m/s)</b>: seed terminal velocity (m/s) data derived from the referenced study or LEDA (Kleyer et al. 2008) database</p> <p><b>Maximum_recorded_dispersal_distance_(m)</b>: species’ maximum dispersal distance (m) found in the literature corresponding to a specific dispersal syndrome</p> <p><b>99th_percentile_dispersal_distance_(m)</b>: 99th percentile of a species’ dispersal distance distribution (m) corresponding to a specific dispersal syndrome</p> <p><b>90th_percentile_dispersal_distance_(m)</b>: 90th percentile of a species’ dispersal distance distribution (m) corresponding to a specific dispersal syndrome</p> <p><b>Mean_dispersal_distance_(m)</b>: species’ mean dispersal distance (m) corresponding to a specific dispersal syndrome<b> </b></p> <p><b>Mode_dispersal_distance_(m)</b>: mode of a species’ dispersal distance distribution (m) corresponding to a specific dispersal syndrome</p> <p><b>Median_dispersal_distance_(m)</b>: median of a species’ dispersal distance distribution (m) corresponding to a specific dispersal syndrome</p> <p><b>Maximum_dispersal_distance_(m)</b>: equals to maximum_recorded_dispersal_distance_(m) if given, otherwise equals to 99th_percentile_dispersal_distance_(m) or 90th_percentile_dispersal_distance_(m)</p> <p><b>Calculated_maximum_dispersal_distance_(m)</b>: when no maximum dispersal distance data was available, we estimated maximum dispersal distance using the formula log10(maximum) = 0.795 + 0.984 * log10(mean); if mean dispersal distance was not available, we used the mode or median of a species’ dispersal distance distribution </p> <p><b>Maximum_dispersal_distance_analysis_(m)</b>: data used in the analyses, equals to Maximum_dispersal_distance_(m) or (if maximum was not available) to Calculated_maximum_dispersal_distance_(m)</p> <p><b>Data_type</b>: denotes whether data source was an observational (‘field’) or modeling (‘model’) study</p> <p><b>Region</b>: region of the case study, categories include ‘temperate’ or ‘tropics’</p> <p><b>Reference</b>: reference for a data source</p> </blockquote> <p> </p> </div

Appendix A. Overview of the results for linear models to explain maximum dispersal distances using different combinations of plant traits, and histograms of maximum dispersal distance data for different dispersal syndromes and growth forms.

Overview of the results for linear models to explain maximum dispersal distances using different combinations of plant traits, and histograms of maximum dispersal distance data for different dispersal syndromes and growth forms

Appendix B. Overview of the predictive power of models with random and fixed effects included in the models.

Overview of the predictive power of models with random and fixed effects included in the models

Plant dispersal data

Plant dispersal dat