The anatomical structure of roots determines their function. Coexisting species complementarily forage nutrients by roots themselves (e.g., root strategy) and their fungal partners (e.g., mycorrhizal strategy), leading to a tradeoff between root strategy and mycorrhizal strategy. However, few studies have specifically evaluated whether and how the root anatomical structures are involved in this tradeoff, especially for species in alpine ecosystems limited by extreme climate.Here, absorptive root anatomical and chemical traits and three key root traits commonly associated with nutrient foraging strategies, i.e., root strategy indicated by first-order root length and root branching intensity and mycorrhizal strategy indicated by arbuscular mycorrhizal fungal colonization, were examined across 68 herbaceous species in alpine meadows of the Tibetan Plateau.We observed that absorptive roots with higher branching intensity had more protoxylem poles, thinner cortices and smaller cortical cells, whereas absorptive roots with higher mycorrhizal colonization and longer first-order roots consistently had thicker cortices and larger cortical cells. Unexpectedly, root cortical traits responsible for nutrient uptake were decoupled from stelar traits specialized in water and nutrient transportation. The decoupling may be related to the non-coordinated changes in soil water and nutrient availability in the meadows of the Tibetan Plateau. In addition, we found that root cortical thickness and stelar radius increased at a similar rate rather than well-reported different rates with increasing root diameter. Our results demonstrate that root internal makeup plays an integral role in forming the diverse nutrient foraging strategies in belowground. These findings provide new insights into our understanding of plant coexistence and responses of alpine meadows to climate change on the Tibetan Plateau.

 

In this study we measured the anatomical traits, morphological traits and arbuscular mycorrhizal fungal colonization of absorptive roots of 68 herbaceous species in alpine meadows of the Tibetan Plateau. 

 

 

These data were collected in alpine meadows of the Tibetan Plateau. Three sites are selected. Site 1 was in Hongyuan County, Sichuan Province, and Sites 2 and 3 were in Gannan Grassland Ecosysstem National Obervation and Research Station, Gansu Province, P.R., China.  Details for each dataset are provided in the README file.

 

 

All root trait data collected in this study. Columns include species names, family names, plant growth form, and root traits. Abbreviations and units are as follows. Root diameter (RD, μm), cortical thickness (CT, μm), cortical cell diameter (CCDM, μm), cortical cell density (CCDS,×10² mm^-2), stelar diameter (SD,μm), vessel diameter (VDM,μm), vessel density, (VDS,×10² mm^-2), protoxylem pole number (PXP), nitrogen concentration(NC, %), carbon concentration (CC, %), root branching intensity(BI, cm^-1), first-order root length (RL, cm), mycorrhizal colonization (MC, %).