DOI: 10.5061/dryad.t1g1jwtfj
title: Structural diversity surpasses species diversity in regulating the spatial variation of grassland productivity

description: Understanding the influence of biodiversity on ecosystem productivity
 remains an important question in ecology. Recent evidence indicated that
 structural diversity plays a critical role in regulating plant
 productivity. However, empirical studies examining the relationship
 between community structure and plant productivity across different
 environments in grassland ecosystems remain limited. This is partly
 because of the perceived simplicity of grassland structure and
 methodological challenges inherent in conducting detailed structural
 surveys. In this study, we investigated the contributions of structural
 and species diversity to grassland productivity and their associated
 interactions along a precipitation gradient on the Mongolian Plateau. We
 collected precise coordinate and height data for 55,311 individual plants
 across distinct grassland types, enabling a systematic assessment of both
 vertical and horizontal structural dimensions. We hypothesized that
 structural diversity, encompassing both axes, would be a primary
 determinant of grassland productivity, with the dominant structural
 dimensions shifting across the moisture gradient. We revealed that the
 relative contribution of structural diversity to productivity (77%) was
 much higher than that of species diversity (23%) in the grassland
 ecosystems of the Mongolian Plateau. However, the relative importance of
 species diversity, vertical structure, and horizontal structure varied
 across the grassland types. Specifically, along the precipitation gradient
 from the desert to meadow steppe, the key factors influencing productivity
 changed from species diversity to vertical structure and ultimately to
 horizontal structure. Synthesis. These findings highlight the important,
 yet often overlooked, role of structural diversity in predicting grassland
 productivity and confirm the hypothesized shift in dominant structural
 dimensions along environmental gradients. Technological advancements in
 remote sensing, particularly the application of Light Detection and
 Ranging (LiDAR), provide promising avenues for large-scale,
 high-resolution structural assessments. These tools may substantially
 enhance our understanding of grassland ecosystem dynamics and inform more
 effective management and conservation strategies.
description: # Structural diversity surpasses species diversity in regulating the
 spatial variation of grassland productivity Dataset DOI:
 [10.5061/dryad.t1g1jwtfj](10.5061/dryad.t1g1jwtfj) ## Description of the
 data and file structure Species diversity and structural diversity
 information of all plots. ### Files and variables #### File:
 grass_plants_data.xlsx **Description:**  ##### Variables * Plot: plot ID
 of the data, categorical variable * Site: site ID of the data, categorical
 variable * AGB: above ground biomass, kg m^-2  * Species_Richness: species
 richness of grassland community at each plot, count * Shannon_Index:
 species diversity index of Shannon, unitless * Simpson_Index: species
 diversity index of Simpson, unitless * Pielou_Evenness: species diversity
 index of evenness, unitless * Mean_height: the mean height of grass plants
 in each plot, cm * GC: Gini coefficient, unitless * CV: coefficient of
 variation of plants height, unitless * VSR: vertical structural richness,
 count * H-Shannon: height-based Shannon–Wiener index, unitless *
 M: mingling index of grassland communtiy, unitless * W: the uniform angle
 index of grassland communtiy, unitless * ph: the pH of soil sample, pH
 units * OM: soil organic matter, % * AP: soil available phosphorus, mg
 kg^-1 * AN: soil available nitrogen, mg kg^-1 ## Code/software Excel