DOI: 10.5061/dryad.hhmgqnkwk
title: Coupled hydrological niche segregation and the leaf economic spectrum explain coexistence of woody species in a natural secondary forest

description: By contrasting water sources and diverging in leaf economic traits, plants
 regulate and balance their use of water, carbon, and nutrient resources,
 thereby potentially promoting species coexistence. However, how these
 strategies affect species coexistence is unclear. We quantified the
 relative contributions of different water sources (topsoil water, 0–20 cm;
 subsoil water, 20–200 cm), intrinsic water use efficiency (WUEi), key LES
 traits, and the importance value index (a proxy for species dominance),
 across the ten coexisting plant species in a natural secondary forest at
 Ziwuling Mountains of the Loess Plateau (LP), Northwest China. Our results
 showed the large variability in water source utilisation, WUEi, leaf N, P
 contents, and specific leaf area (SLA) among species, indicating diverse
 resource use strategies. Differences in water sources resulting in varying
 degrees of water competition between species, ranging from 47 to 81%. The
 water source utilised by plants was coordinated with the LES. Species that
 relied on topsoil water, characterised by nutrient-rich but variable water
 supply, adopted acquisitive strategies, exhibiting high leaf N, P contents
 and SLA. In contrast, species relying on subsoil water, which provides
 relatively low-nutrient availability but a stable water supply, adopted
 conservative strategies, displaying opposite traits. Notably, species with
 conservative strategies dominated in the community. Synthesis. Our
 findings highlight a tight coupling between plant water sources and the
 LES, which jointly influence species coexistence and dominance. Our study
 evaluated the persistence and coexistence strategies of the ten species in
 a natural secondary forest, which serves as a reference for the tree
 species selection of afforestation in the LP, or similar regions.
description: # Coupled hydrological niche segregation and the leaf economic spectrum
 explain coexistence of woody species in a natural secondary forest Dataset
 DOI: [10.5061/dryad.hhmgqnkwk](https://doi.org/10.5061/dryad.hhmgqnkwk) ##
 Description of the data and file structure This study was conducted in a
 natural secondary forest located in the Ziwuling Mountains of the Loess
 Plateau, Northwest China. From May to September 2023, monthly field
 sampling was carried out. We collected xylem water samples from the ten
 woody species branches, along with soil samples from eight depths (10, 20,
 30, 50, 80, 100, 150, and 200 cm) for stable hydrogen and oxygen isotope
 analysis (δ^2^H and δ^18^O). We also measured leaf δ^13^C and wood density
 (WD) to analyse the physiological regulation and hydraulic trait of plant
 species. In addition, we measured leaf nutrients (N, P), the specific leaf
 area (SLA), and leaf dry matter content (LDMC) known to be key functional
 traits in the leaf economic spectrum. ### Files and variables #### File:
 Coupled_hydrological_niche_segregation_and_the_leaf_economic_spectrum_explain_coexistence_of_woody_species_in_a_natural_secondary_forest_data_for_Dryad.xlsx **Description:** This dataset comprises three primary data sheets documenting stable isotope measurements in soil-plant systems and plant functional traits. The “data description" sheet provides a comprehensive overview of the dataset. The "Isotopic data" sheet is divided into two subsections: "Soil water" and "Plant xylem water." The soil water data includes monthly mean δ²H and δ¹⁸O values (‰) with their corresponding standard deviations (SD) across eight soil depths (10, 20, 30, 50, 80, 100, 150, and 200 cm) from May to September. The plant xylem water data provides δ²H and δ¹⁸O values (‰) with SDs for ten woody species (abbreviated as QW, PT, PO, PD, CP, VS, RX, CZ, AG, LF) during the same period, along with the calculated percentage contributions of topsoil and subsoil water to plant root uptake. The "Functional traits" sheet contains mean values and SDs for key leaf and wood traits measured across species, including Leaf Nitrogen (Leaf N) and Phosphorus (Leaf P) content (mg/g), Intrinsic Water Use Efficiency (WUEi, μmmol/mol), Leaf Dry Matter Content (LDMC, mg/g), Specific Leaf Area (SLA, m²/kg), and Wood Density (WD, cm/g). All data are presented as mean values with associated standard deviations to indicate variability. ##### Variables * Species：(*Quercus wutaishanica* Mayr, QW; *Pinus tabuliformis* Carr, PT; *Platycladus orientalis* (L.) Franco, PO; *Populus davidiana*, PD; *Cerasus pseudocerasus*, CP; *Viburnum schensianum* Maxim, VS; *Rosa xanthina* Lindl; RX; *Cotoneaster zabelii* C. K. Schneid; CZ; *Acer ginnala* Maxim, AG; *Lonicera ferdinandii* Franch, LF) * Month (May -September) ## Code/software Excel ## Access information Other publicly accessible locations of the data: * 
 
 Data was derived from the following sources: *