Data

This dataset contains first‑order root trait raw data collected from three global root trait databases—Fine Root Ecological Database (FRED), Global Root Trait Database (Groot), and TRY Plant Trait Database (TRY)—spanning the years 2000 to 2025. It also includes derived indicators calculated from the raw data. The dataset is used to validate the model proposed in the accompanying paper. File content: This Excel file consists of 5 worksheets (Sheets). The structure of each sheet is similar. The main fields are described below (columns marked with * are derived data calculated from raw data; blank cells in the table indicate that no raw measurement value is available for that data point, marked as blank or NA): Sheet 1 – First‑order root data of herbs on the Qinghai‑Tibet PlateauRaw variables: species name, growth form, stele diameter (Ds), total cortex thickness (TCT), originally measured root diameter (ORD), root length (RL). Derived variables: calculated root diameter (RD), root cross‑sectional area (RCSA), stele cross‑sectional area (SCSA), cortex cross‑sectional area (CCSA), root volume (Vc), product of root volume and root length (Vc·L), and the fourth power of stele diameter (*Ds4). Sheet 2 – First‑order root data of herbs in Inner MongoliaRaw variables: species name, taxonomic family, growth form, originally measured root diameter (ORD), root length (RL). Derived variable: calculated stele diameter (*Ds), obtained by back‑calculation from the raw root diameter data in Sheet 2 using the allometric relationship between stele diameter and root diameter established from Sheet 3. Sheet 3 – Global first‑order root data of herbs (Note: Sheet 3 contains global herb data and does not include the samples from Sheet 1 (Qinghai‑Tibet) and Sheet 2 (Inner Mongolia) because the former has special site conditions and the latter lacks some indicators.)Raw variables: species name, stele diameter (Ds), total cortex thickness (TCT), originally measured root diameter (ORD). Derived variables: calculated root diameter (RD), root cross‑sectional area (RCSA), stele cross‑sectional area (SCSA), cortex cross‑sectional area (CCSA). Sheet 4 – First‑order root data of subtropical woody plantsRaw variables: species name, taxonomic family, growth form, mycorrhizal type, location, stele diameter (Ds), total cortex thickness (TCT), originally measured root diameter (ORD), root length (RL). Derived variables: calculated root diameter (RD), root cross‑sectional area (RCSA), stele cross‑sectional area (SCSA), cortex cross‑sectional area (CCSA), root volume (Vc), product of root volume and root length (Vc·L), and the fourth power of stele diameter (*Ds4). Sheet 5 – Global first‑order root data of woody plants (Sheet 5 contains global woody data, and Sheet 4 data are a subset of it.)Raw variables: species name, mycorrhizal type, stele diameter (Ds), total cortex thickness (TCT), originally measured root diameter (ORD). Derived variables: calculated root diameter (RD), root cross‑sectional area (RCSA), stele cross‑sectional area (SCSA), cortex cross‑sectional area (CCSA).