DOI: 10.5061/dryad.1ns1rn938
title: A global dataset on paired leaf Na and root Na contents

description: Aim: Plants allocate sodium (Na) to leaves and roots as an adaptation to
 salinity and drought, potentially modulating herbivory and ecosystem
 carbon cycling. However, large-scale spatial pattern and environmental
 drivers of plant Na allocation remain unclear.Location: China and the
 world.Time period: Field data were collected between 2013 and 2019.
 Literature data were collected between 1970 and 2024.Major taxa studied:
 Vascular plants.Methods: We compiled a global database of paired leaf Na
 (NaLeaf) and root Na (NaRoot) content, combining field observations from
 2183 species across 72 Chinese ecosystems with global synthesized
 literature records.Results: The spatial pattern of plant Na allocation
 between leaves and roots is primarily regulated by aridity. Generally,
 plants allocate more Na to roots in humid zone but more to leaves in arid
 zone. Furthermore, aridification leads to abrupt and nonlinear increases
 in the NaLeaf to NaRoot ratio (NaLeaf: Root) when aridity exceeds critical
 threshold (0.814 for the Chinese plant species and 0.774 for the Chinese
 plant community). Importantly, the threshold response is consistently
 observed from species to community levels and from China to global
 biomes.Main conclusions: Our findings demonstrate the flexible allocation
 of plant Na in response to salinity and drought on a large scale.
 Projected aridification could amplify leaf Na allocation in
 threshold-exceeding regions, possibly enhancing activity of herbivores and
 decomposers and triggering cascading impacts on plant community structure
 and carbon cycling rate.
description: Based on a field investigation following the consistent method,
 we compiled a regional dataset of the Na content in paired leaves
 (Na<sub>Leaf</sub>) and roots (Na<sub>Root</sub>),
 which included 2183 species from 72 natural ecosystems in China. We also
 synthesized literature data on paired NaLeaf and NaRoot contents across
 global terrestrial ecosystems at the species level. First, we used ISI Web
 of Science (https://webofscience.clarivate.cn/wos) and Google Scholar
 (http://scholar.google.com) for a 1970–2024 literature search with the
 following keywords: “sodium” OR “Na” OR “mineral element” OR “beneficial
 element” AND “leaf and root” OR “plant organ” AND “forest” OR “grassland”
 OR “desert.” Second, we screened all literature and extracted leaf and
 root Na contents based on the following criteria: (i) reported paired
 observations of NaLeaf and NaRoot from mature individuals; (ii) plants
 were collected from terrestrial ecosystems, specifically forests,
 grasslands, and deserts; and (iii) plants were sampled in the field rather
 than through greenhouse experiments. Third, ancillary information,
 including the species name, life form (tree, shrub, and herb), vegetation
 type (forest, grassland, and desert), and geographical location (latitude
 and longitude), was collected. Data from multiple years at the same
 sampling site were averaged to ensure independence of observations. When
 data were only available as figures, the GetData Graph Digitizer
 (http://www.getdata-graph-digitizer.com) was used. Overall, 70 independent
 publications were included. The final global dataset contained 175 paired
 measurements of NaLeaf and NaRoot from 169 species (56 families) spanning
 70 sites worldwide.
description: # Data on paired leaf Na and root Na content across global terrestrial
 ecosystems
 [https://doi.org/10.5061/dryad.1ns1rn938](https://doi.org/10.5061/dryad.1ns1rn938) ## Description of the data and file structure We synthesized literature data on paired NaLeaf and NaRoot contents across global terrestrial ecosystems at the species level. First, we used ISI Web of Science ([https://webofscience.clarivate.cn/wos](https://webofscience.clarivate.cn/wos)) and Google Scholar ([http://scholar.google.com](http://scholar.google.com)) for a 1970–2024 literature search with the following keywords: “sodium” OR “Na” OR “mineral element” OR “beneficial element” AND “leaf and root” OR “plant organ” AND “forest” OR “grassland” OR “desert.” Second, we screened all literature and extracted leaf and root Na contents based on the following criteria: (i) reported paired observations of NaLeaf and NaRoot from mature individuals; (ii) plants were collected from terrestrial ecosystems, specifically forests, grasslands, and deserts; and (iii) plants were sampled in the field rather than through greenhouse experiments. Third, ancillary information, including the species name, life form (tree, shrub, and herb), vegetation type (forest, grassland, and desert), and geographical location (latitude and longitude), was collected. Data from multiple years at the same sampling site were averaged to ensure independence of observations. When data were only available as figures, the GetData Graph Digitizer ([http://www.getdata-graph-digitizer.com](http://www.getdata-graph-digitizer.com)) was used. Overall, 70 independent publications were included. The final global dataset contained 175 paired measurements of NaLeaf and NaRoot from 169 species (56 families) spanning 70 sites worldwide. All missing data represented as NA. Please find more information in the paper by Guo et al., (2025) in Global Ecology and Biogeography. DOI: 10.1111/geb.70025 ### Files and variables **Document: 1-China species Na** **Description:**  Paired species leaf Na and root Na contents across 72 Chinese terrestrial ecosystems (average value of each site) ##### Variables SiteID: ID of the sampling sites Name: Name of the sampled sites Latitude: Latitude (°) Longitude: Longitude (°) Leaf Na: Leaf sodium content (g/kg) Root Na: Root sodium content (g/kg) MAT: Mean annual temperature (℃) MAP: Mean annual precipitation (mm) Aridity: Aridity level of site (1 − AI) VPD: Atmospheric vapor pressure deficit (hPa) Soil Na: Soil sodium content (g/kg) (0-10cm) Soil pH: Soil pH (0-10cm) Soil moisture: Soil moisture (0-10cm) Soil clay: Soil clay fraction (%) (0-10cm) **Document: 2-China community Na** **Description:**  Paired community-weighted-mean (CWM) leaf Na and root Na contents across 72 Chinese terrestrial ecosystems (average value of each site) ##### Variables SiteID: ID of the sampling sites Name: Name of the sampled sites Latitude: Latitude (°) Longitude: Longitude (°) Leaf Na: Leaf sodium content (g/kg) Root Na: Root sodium content (g/kg) MAT: Mean annual temperature (℃) MAP: Mean annual precipitation (mm) Aridity: Aridity level of site (1 − AI) VPD: Atmospheric vapor pressure deficit (hPa) Soil Na: Soil sodium content (g/kg) (0-10cm) Soil pH: Soil pH (0-10cm) Soil moisture: Soil moisture (0-10cm) Soil clay: Soil clay fraction (%) (0-10cm) **Document: 3-Global species Na** **Description:** Paired species leaf Na and root Na contents across global terrestrial ecosystems (raw data from publication) ##### Variables Study: Original literature Latitude: Latitude (°) Longitude: Longitude (°) Vegetation type: Dominant vegetation type of the sampled sites Species name: Species name MAT: Mean annual temperature (℃) MAP: Mean annual precipitation (mm) Aridity: Aridity level of site (1 − AI) BC: Broad leaves or coniferous leaves DE: Deciduous leaves or evergreen leaves Life form: Tree or shrub or herb Leaf Na: Leaf sodium content (g/kg) Root Na: Root sodium content (g/kg) ## Code/software R code used for analysis.