Abstract
Plant traits determine how individual plants cope with heterogeneous environments. Despite large variability in individual traits, trait coordination and trade-offs1,2 result in some trait combinations being much more widespread than others, as revealed in the global spectrum of plant form and function (GSPFF3) and the root economics space (RES4) for aboveground and fine-root traits, respectively. Here we combine the traits that define both functional spaces. Our analysis confirms the major trends of the GSPFF and shows that the RES captures additional information. The four dimensions needed to explain the non-redundant information in the dataset can be summarized in an aboveground and a fine-root plane, corresponding to the GSPFF and the RES, respectively. Both planes display high levels of species aggregation, but the differentiation among growth forms, families and biomes is lower on the fine-root plane, which does not include any size-related trait, than on the aboveground plane. As a result, many species with similar fine-root syndromes display contrasting aboveground traits. This highlights the importance of including belowground organs to the GSPFF when exploring the interplay between different natural selection pressures and whole-plant trait integration.
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Data availability
The datasets generated and analysed during the current study are available in the Figshare repository: https://doi.org/10.6084/m9.figshare.13140146.
Code availability
The R code used in the current study is available in the Figshare repository: https://doi.org/10.6084/m9.figshare.13140146.
References
Grime, J. P. Plant Strategies, Vegetation Processes, and Ecosystem Properties (John Wiley and Sons, 2001).
Reich, P. B. et al. The evolution of plant functional variation: traits, spectra, and strategies. Int. J. Plant Sci. 164, S143–S164 (2003).
Díaz, S. et al. The global spectrum of plant form and function. Nature 529, 167–171 (2016).
Bergmann, J. et al. The fungal collaboration gradient dominates the root economics space in plants. Sci. Adv. 6, eaba3756 (2020).
Wright, I. J. et al. The worldwide leaf economics spectrum. Nature 428, 821–827 (2004).
Kattge, J. et al. TRY plant trait database — enhanced coverage and open access. Glob. Chang. Biol. 26, 119–188 (2020).
Iversen, C. M. et al. A global Fine-Root Ecology Database to address below-ground challenges in plant ecology. New Phytol. 215, 15–26 (2017).
Guerrero-Ramírez, N. R. et al. Global root traits (GRooT) database. Glob. Ecol. Biogeogr. 30, 25–37 (2021).
McCormack, M. L. et al. Redefining fine roots improves understanding of below-ground contributions to terrestrial biosphere processes. New Phytol. 207, 505–518 (2015).
Rasse, D. P., Rumpel, C. & Dignac, M. F. Is soil carbon mostly root carbon? Mechanisms for a specific stabilisation. Plant Soil 269, 341–356 (2005).
Eissenstat, D. M. Costs and benefits of constructing roots of small diameter. J. Plant Nutr. 15, 763–782 (1992).
Freschet, G. T., Cornelissen, J. H. C., van Logtestijn, R. S. P. & Aerts, R. Evidence of the ‘plant economics spectrum’ in a subarctic flora. J. Ecol. 98, 362–373 (2010).
Reich, P. B. The world-wide ‘fast–slow’ plant economics spectrum: a traits manifesto. J. Ecol. 102, 275–301 (2014).
Shen, Y. et al. Linking aboveground traits to root traits and local environment: implications of the plant economics spectrum. Front. Plant Sci. 10, 1412 (2019).
Kramer-Walter, K. R. et al. Root traits are multidimensional: specific root length is independent from root tissue density and the plant economic spectrum. J. Ecol. 104, 1299–1310 (2016).
Bergmann, J., Ryo, M., Prati, D., Hempel, S. & Rillig, M. C. Root traits are more than analogues of leaf traits: the case for diaspore mass. New Phytol. 216, 1130–1139 (2017).
Weemstra, M. et al. Towards a multidimensional root trait framework: a tree root review. New Phytol. 211, 1159–1169 (2016).
Ma, Z. et al. Evolutionary history resolves global organization of root functional traits. Nature 555, 94–97 (2018).
de la Riva, E. G. et al. Root traits across environmental gradients in Mediterranean woody communities: are they aligned along the root economics spectrum? Plant Soil 424, 35–48 (2018).
Craine, J. M., Lee, W. G., Bond, W. J., Williams, R. J. & Johnson, L. C. Environmental constraints on a global relationship among leaf and root traits of grasses. Ecology 86, 12–19 (2005).
Liese, R., Alings, K. & Meier, I. C. Root branching is a leading root trait of the plant economics spectrum in temperate trees. Front. Plant Sci. 8, 315 (2017).
Carmona, C. P. et al. Erosion of global functional diversity across the tree of life. Sci. Adv. 7, eabf2675 (2021).
Niklas, K. J. Modelling below- and above-ground biomass for non-woody and woody plants. Ann. Bot. 95, 315–321 (2005).
Liu, G. et al. Coordinated variation in leaf and root traits across multiple spatial scales in Chinese semi-arid and arid ecosystems. New Phytol. 188, 543–553 (2010).
Galland, T., Carmona, C. P., Götzenberger, L., Valencia, E. & de Bello, F. Are redundancy indices redundant? An evaluation based on parameterized simulations. Ecol. Indic. 116, 106488 (2020).
Valverde‐Barrantes, O. J., Maherali, H., Baraloto, C. & Blackwood, C. B. Independent evolutionary changes in fine‐root traits among main clades during the diversification of seed plants. New Phytol. 228, 541–553 (2020).
Cornwell, W. K. et al. Plant species traits are the predominant control on litter decomposition rates within biomes worldwide. Ecol. Lett. 11, 1065–1071 (2008).
Freschet, G. T. et al. Climate, soil and plant functional types as drivers of global fine-root trait variation. J. Ecol. 105, 1182–1196 (2017).
De Deyn, G. B. & Van der Putten, W. H. Linking aboveground and belowground diversity. Trends Ecol. Evol. 20, 625–633 (2005).
Pausas, J. G. & Bond, W. J. Humboldt and the reinvention of nature. J. Ecol. 107, 1031–1037 (2019).
Poorter, H. et al. Biomass allocation to leaves, stems and roots: meta-analyses of interspecific variation and environmental control. New Phytol. 193, 30–50 (2012).
Moora, M. Mycorrhizal traits and plant communities: perspectives for integration. J. Veg. Sci. 25, 1126–1132 (2014).
Freschet, G. T. et al. Root traits as drivers of plant and ecosystem functioning: current understanding, pitfalls and future research needs. New Phytol. https://doi.org/10.1111/nph.17072 (2021).
McCormack, M. L. & Iversen, C. M. Physical and functional constraints on viable belowground acquisition strategies. Front. Plant Sci. 10, 1215 (2019).
Wells, C. E. & Eissenstat, D. M. Beyond the roots of young seedlings: the influence of age and order on fine root physiology. J. Plant Growth Regul. 21, 324–334 (2002).
Zanne, A. E. et al. Three keys to the radiation of angiosperms into freezing environments. Nature 506, 89–92 (2014).
USDA. USDA PLANTS Database (accessed 3rd July 2020); https://plants.sc.egov.usda.gov
Engemann, K. et al. A plant growth form dataset for the New World. Ecology 97, 3243 (2016).
BGCI. GlobalTreeSearch online database (accessed 3rd July 2020); https://www.bgci.org/globaltree_search.php
The Plant List. The Plant List (accessed 17th February 2020); http://www.theplantlist.org
Cayuela, L., Macarro, I., Stein, A. & Oksanen, J. Taxonstand: Taxonomic Standardization of Plant Species Names. R package version 2.2. https://CRAN.R-project.org/package=Taxonstand (2019).
Stekhoven, D. J. & Buhlmann, P. MissForest—non-parametric missing value imputation for mixed-type data. Bioinformatics 28, 112–118 (2012).
Oliveira, B. F., Sheffers, B. R. & Costa, G. C. Decoupled erosion of amphibians’ phylogenetic and functional diversity due to extinction. Glob. Ecol. Biogeogr. 29, 309–319 (2020).
Penone, C. et al. Imputation of missing data in life-history trait datasets: which approach performs the best? Methods Ecol. Evol. 5, 961–970 (2014).
Jin, Y. & Qian, H. V.PhyloMaker: an R package that can generate very large phylogenies for vascular plants. Ecography 42, 1353–1359 (2019).
Smith, S. A. & Brown, J. W. Constructing a broadly inclusive seed plant phylogeny. Am. J. Bot. 105, 302–314 (2018).
Whittakker, R. H. Communities and Ecosystems (Macmillan, 1975).
Stefan, V. & Levin, S. plotbiomes: Plot Whittaker biomes with ggplot2. R package version 0.0.0.9001 https://github.com/valentinitnelav/plotbiomes (2021).
Ricklefs, R. E. The Economy of Nature (W. H. Freeman and Company, 2008).
GBIF. GBIF Occurrence Download (accessed 15 December 2019); https://doi.org/10.15468/dl.thlxph
South, A. rworldmap: a new R package for mapping global data. R J. 3, 35–43 (2011).
Dinno, A. paran: Horn’s Test of Principal Components/Factors. R package version 1.5.2. https://CRAN.R-project.org/package=paran (2018).
Dray, S. & Dufour, A.-B. The ade4 package: implementing the duality diagram for ecologists. J. Stat. Softw. https://doi.org/10.18637/jss.v022.i04 (2007).
Duong, T. ks: kernel density estimation and kernel discriminant analysis for multivariate data in R. J. Stat. Softw. https://doi.org/10.18637/jss.v021.i07 (2015).
Duong, T. ks: Kernel smoothing. R package version 1.11.5 https://CRAN.R-project.org/package=ks (2019).
Carmona, C. P., Bello, F., Mason, N. W. H. & Lepš, J. Trait probability density (TPD): measuring functional diversity across scales based on TPD with R. Ecology 100, e02876 (2019).
Carmona, C. P. TPD: methods for measuring functional diversity based on Trait Probability Density. R package version 1.1.0. https://CRAN.R-project.org/package=TPD (2019).
Duong, T. & Hazelton, M. L. Plug-in bandwidth matrices for bivariate kernel density estimation. J. Nonparametr. Stat. 15, 17–30 (2003).
Carmona, C. P., de Bello, F., Mason, N. W. H. & Lepš, J. Traits without borders: integrating functional diversity across scales. Trends Ecol. Evol. 31, 382–394 (2016).
Mason, N. W. H., Mouillot, D., Lee, W. G. & Wilson, J. B. Functional richness, functional evenness and functional divergence: the primary components of functional diversity. Oikos 111, 112–118 (2005).
Villéger, S., Mason, N. W. H. & Mouillot, D. New multidimensional functional diversity indices for a multifaceted framework in functional ecology. Ecology 89, 2290–2301 (2008).
Oksanen, J. et al. vegan: Community Ecology Package. R package version 2.5-5 https://CRAN.R-project.org/package=vegan (2019).
Carmona, C. P. et al. Taxonomical and functional diversity turnover in Mediterranean grasslands: interactions between grazing, habitat type and rainfall. J. Appl. Ecol. 49, 1084–1093 (2012).
Micó, E. et al. Contrasting functional structure of saproxylic beetle assemblages associated to different microhabitats. Sci. Rep. 10, 1520 (2020).
Blonder, B. et al. New approaches for delineating n-dimensional hypervolumes. Methods Ecol. Evol. 9, 305–319 (2018).
Carmona, C. P., de Bello, F., Mason, N. W. H. & Lepš, J. The density awakens: a reply to Blonder. Trends Ecol. Evol. 31, 667–669 (2016).
Mouillot, D. et al. Niche overlap estimates based on quantitative functional traits: a new family of non-parametric indices. Oecologia 145, 345–353 (2005).
de Bello, F., Carmona, C. P., Mason, N. W. H., Sebastià, M.-T. & Lepš, J. Which trait dissimilarity for functional diversity: trait means or trait overlap? J. Veg. Sci. 24, 807–819 (2013).
Traba, J., Iranzo, E. C., Carmona, C. P. & Malo, J. E. Realised niche changes in a native herbivore assemblage associated with the presence of livestock. Oikos 126, 1400–1409 (2017).
Cornwell, W. K., Schwilk, D. W. & Ackerly, D. D. A trait-based test for habitat filtering: Convex Hull Volume. Ecology 87, 1465–1471 (2006).
Blonder, B., Lamanna, C., Violle, C. & Enquist, B. J. The n-dimensional hypervolume. Glob. Ecol. Biogeogr. 23, 595–609 (2014).
Blonder, B. Hypervolume concepts in niche- and trait-based ecology. Ecography 41, 1441–1455 (2018).
Ricotta, C. et al. Measuring the functional redundancy of biological communities: a quantitative guide. Methods Ecol. Evol. 7, 1386–1395 (2016).
Mouillot, D. et al. Functional over-redundancy and high functional vulnerability in global fish faunas on tropical reefs. Proc. Natl. Acad. Sci. USA 111, 13757–13762 (2014).
Carmona, C. P., de Bello, F., Sasaki, T., Uchida, K. & Pärtel, M. Towards a common toolbox for rarity: a response to Violle et al. Trends Ecol. Evol. 32, 889–891 (2017).
Violle, C. et al. Functional rarity: the ecology of outliers. Trends Ecol. Evol. 32, 356–367 (2017).
Borcard, D., Legendre, P. & Drapeau, P. Partialling out the spatial component of ecological variation. Ecology 73, 1045–1055 (1992).
Gower, J. C. General coefficient of similarity and some of its properties. Biometrics 27, 857–871 (1971).
Carmona, C. P. et al. Agriculture intensification reduces plant taxonomic and functional diversity across European arable systems. Funct. Ecol. 34, 1448–1460 (2020).
Gherardi, L. A. & Sala, O. E. Global patterns and climatic controls of belowground net carbon fixation. Proc. Natl Acad. Sci. USA 117, 20038–20043 (2020).
Acknowledgements
This study has been supported by the TRY initiative on plant traits (http://www.try-db.org). The TRY initiative and database is hosted, developed and maintained by J. Kattge and G. Boenisch (Max Planck Institute for Biogeochemistry, Jena, Germany). TRY is currently supported by Future Earth/bioDISCOVERY and the German Centre for Integrative Biodiversity Research (iDiv) Halle–Jena–Leipzig. This study was financed by the Estonian Ministry of Education and Research (PSG293 for C.P.C., C.G.B., S.T. and R.T.; PRG609 for M.P. and R.T.; PSG505 for A.T.; and PRG1065 for M.M., M.Z. and C.G.B.), by the European Union through the European Regional Development Fund (Centre of Excellence EcolChange), the University of Tartu (PLTOM20903). S.D. received partial funding from CONICET, FONCyT and Universidad Nacional de Córdoba (Argentina), IAI SGP and the Newton Fund. Partial funding for A.D.M. is from the Natural Sciences and Engineering Research Council of Canada.
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C.P.C., C.G.B., A.T., S.T., M.M. and R.T. conceived the study. R.T. and C.P.C. collected and processed the trait data. A.T. and S.T. collected and processed the biogeographical and climate data. C.P.C. and A.T. analysed the data with input from all authors. C.G.B., S.T. and R.T. performed a literature search. C.P.C. wrote a first draft of the manuscript, assisted by C.G.B., A.T., S.T. and R.T. S.D., M.M., A.M., M.P. and M.Z. contributed to the design of analyses, interpretation of results and article writing.
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Extended data figures and tables
Extended Data Fig. 1 Correlations between traits.
Pairwise correlations between the considered traits in the different datasets (black: full dataset with 1,719 species, blue: imputed dataset with 1,218 species, orange: complete dataset with 301 species). The lower-left triangle of the matrix contains scatterplots of traits (after log-10 transformation) showing the relationship (including regression lines) between each pair of traits. The diagonal includes a probability density function showing the distribution of each individual trait. The upper-right triangle includes the value of the correlation coefficients and, in the case of the full dataset, the number of species with empirical data for both traits (imputed and complete dataset always considered the same numbers of species). Lines for each dataset have different thickness to allow visualization of the correlation and probability density function even when there is high overlap between lines corresponding to different datasets.
Extended Data Fig. 2 Geographical, climatic and phylogenetic cover of the datasets.
a, Global map (Robinson projection) showing the occurrences (according to GBIF: http://www.gbif.org) of the species in the imputed dataset (1,218 species with empirical information for at least three aboveground and two fine-root traits). b, Number of species present in the major biomes47 in the imputed dataset (in parentheses, number of species in the complete dataset). c, Distribution of species across the phylogeny of vascular plants excluding ferns (Polypodiopsida) and lycopods (Lycopodiopsida) in the complete (301 species) and imputed datasets.
Extended Data Fig. 3 Individual aboveground and fine-root functional spaces.
Probabilistic distributions of the 2,630 and 748 species with complete empirical information for aboveground (a) and fine-root (b) traits in the functional spaces defined by a PCA on the corresponding traits followed by varimax rotation. The colour gradient (red-yellow-white) depicts different density of species in the defined space (red areas are more densely populated). Arrow length is proportional to the loadings of the considered traits in the resulting space. Aboveground traits are represented in green tones and fine-root traits in brown tones. Thick contour lines indicate the 0.5 and 0.99 quantiles, and thinner lines indicate quantiles 0.6, 0.7, 0.8 and 0.9.
Extended Data Fig. 4 Functional space using the complete dataset.
Probabilistic distributions of the 301 species with complete empirical information in the functional space defined by a PCA followed by varimax rotation based on both aboveground and fine-root traits. Each panel shows a combination of two of the four components that define the full plant spectrum. The colour gradient (red-yellow-white) depicts different density of species in the defined space (red areas are more densely populated). Arrow length is proportional to the loadings of the considered traits in the resulting space. Only those traits that had a loading of at least 0.3 in any of the represented components are shown to improve visualization (see loadings of all components in table S2). Aboveground traits are represented in green tones and fine-root traits in brown tones. Thick contour lines indicate the 0.5 and 0.99 quantiles, and thinner lines indicate quantiles 0.6, 0.7, 0.8 and 0.9.
Extended Data Fig. 5 Comparison of the occupation of the functional space with multivariate normal distributions.
Functional richness profile (amount of functional space occupied by quantiles of the functional spectra), difference in % of functional space occupied with respect to the null models, and functional divergence (representing the degree to which the density of species in the trait space is distributed towards the extremes of the distribution of species; right column) considering the first and second (a), third and fourth (b) and all components (c). In the functional profile plots (top of the left column in each case) green lines represent the mean, 2.5% and 97.5% quantiles of the functional richness profiles of null models (n = 499) representing multivariate normal distributions with equivalent parameters (means and standard deviations) than the observed data; orange lines represent the functional richness profile of the observed spectra. The values of functional richness for the 0.5 and 0.99 quantiles of all profiles are shown for comparison. The difference plots (bottom of the left column in each case), represent the percentage of functional space occupied by each quantile in relation to the mean of the null models; negative percentages mean that the considered quantile of the observed distribution occupies less space than the average of the null models, and vice versa. Each repetition of the null model (n = 499) is represented with a thin green line, whereas thicker green lines represent the mean, 2.5% and 97.5% quantiles of the 499 null models, and the orange line represents the observed distribution. The right column of each case represents the observed and null values of functional divergence; two-sided p values were estimated by confronting the value of the Standardize Effect Size (SES) with the cumulative normal distribution with mean = 0 and standard deviation = 1. The centre, bounds of box, and whiskers of the boxplot represent the median, 25th and 75th percentiles, and 1.5 times the interquartile range, respectively.
Extended Data Fig. 6 Functional space using the imputed dataset.
Probabilistic distributions of the 1,218 species with information for at least three aboveground and two fine-root traits (imputed dataset) in the functional space defined by a PCA followed by varimax rotation based on both aboveground and fine-root traits of the subset of species with complete empirical information. Each panel shows a combination of two of the four components that define the full plant spectrum. The colour gradient (red-yellow-white) depicts different density of species in the defined space (red areas are more densely populated). Arrow lengths are proportional to the loadings of the considered traits in the resulting space. Only those traits that had a loading of at least 0.4 in any of the represented components are shown to improve visualization (see loadings of all components in Extended Data Table 2). Aboveground traits are represented in green tones and fine-root traits in brown tones. Thick contour lines indicate the 0.5 and 0.99 quantiles, and thinner lines indicate quantiles 0.6, 0.7, 0.8 and 0.9.
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Carmona, C.P., Bueno, C.G., Toussaint, A. et al. Fine-root traits in the global spectrum of plant form and function. Nature 597, 683–687 (2021). https://doi.org/10.1038/s41586-021-03871-y
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DOI: https://doi.org/10.1038/s41586-021-03871-y
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