DOI: 10.5061/dryad.7pvmcvdxt
title: Data from: Plant traits and tissue stoichiometry explain nutrient transfer in common arbuscular mycorrhizal networks of temperate grasslands

description: Plants and mycorrhizal fungi form mutualistic relationships that affect
 how resources flow between organisms and within ecosystems. Common
 mycorrhizal networks (CMNs) could facilitate preferential transfer of
 carbon and limiting nutrients but this remains difficult to predict. Do
 CMNs favor fungal growth at the expense of plant resource demands (a
 fungi-centric view), or are they passive channels through which plants
 regulate resource fluxes (a plant-centric view)? We used stable isotope
 tracers (13CO2 and 15NH3), plant traits, and mycorrhizal DNA to quantify
 above- and belowground carbon and nitrogen transfer between 18 plant
 species along a 520-km latitudinal gradient in the Pacific Northwest, USA.
 Plant functional type and tissue stoichiometry were the most important
 predictors of interspecific resource transfer. Of “donor” plants, 98% were
 13C enriched, but we detected transfer in only 2% of “receiver” plants.
 However, all donors were 15N enriched and we detected transfer in 81% of
 receivers. Nitrogen was preferentially transferred to annuals (0.26 ± 0.50
 mg N per g leaf mass) compared to perennials (0.13 ± 0.30 mg N per g leaf
 mass). This corresponded with tissue stoichiometry differences. Our
 findings point to a simple mechanistic answer for long-standing questions
 regarding transfer of resources between plants via mycorrhizal networks.
  
description: # Title of Dataset: Agnostic fungi: plant traits and tissue stoichiometry
 explain nutrient transfer in common arbuscular mycorrhizal networks of
 temperate grasslands Authors: Hilary Rose Dawson, Katherine L. Shek, Toby
 M. Maxwell, Paul B. Reed, Barbara Bomfim, Scott Bridgham, Brendan
 Bohannan, Lucas C.R. Silva --- ## Description of the data and file
 structure Plants and mycorrhizal fungi form close mutualistic
 relationships that affect the structure and function of ecosystems. Recent
 studies show how some plant communities can form associations with the
 same mycorrhizal fungus leading to preferential transfer of carbon and
 limiting nutrients, such as nitrogen, between different species through
 common mycorrhizal networks. This phenomenon has been documented in a wide
 range of ecosystems but its mechanisms remain poorly understood. A core
 question is whether common mycorrhizal networks favor fungal growth at the
 expense of plant resource demands (i.e., a fungi-centric view) or are
 passive channels through which plants regulate resource fluxes (i.e., a
 plant-centric view). In an experimental restored prairie and pasture plant
 systems, replicated at three sites across a 520 km latitudinal gradient in
 the Pacific Northwest, USA, we identified general processes that reconcile
 competing hypotheses related to resource transfer in common mycorrhizal
 networks. We used stable isotope tracers, paired with analyses of fungal
 DNA and plant and fungal community structure and traits, to quantify
 above- and belowground allocation and transfer of carbon and nitrogen
 between 18 different plant species. We applied isotopically enriched
 carbon (13C) and nitrogen (15N) as a pulse of carbon dioxide (CO2) and
 ammonia (NH3) to the leaves of target donor species common across
 experimental sites. At each site, we performed &gt;1360 measurements of
 foliar and root isotopic enrichment, which revealed morphological traits
 and tissue stoichiometry as the most important predictors of interspecific
 resource transfer. Labeled donor plants assimilated isotopic tracers at
 similar rates between sites and experimental treatments. However, carbon
 and nitrogen was preferentially transferred to annual and forb receiver
 plants compared to perennial and grass receiver plants due to differences
 in tissue stoichiometry. Our findings point to a simple mechanistic answer
 for long-standing questions regarding mutualism and transfer of resources
 between plants via mycorrhizal networks, an explanation that can lead to
 general predictions of preferential flow of limiting resources in other
 ecosystems. ## Data Dictionary for 2023.06.01\_AgnosticFungi.csv See also
 a csv that also has this data dictionary | Variable | Full name | Unit |
 Levels | | :------------- | :--------------------------------- |
 :--------------------------------------------------------------------------------- | :--------------------------------------------------------------------------------------------------------------------------- | | sampleID | Sample ID | | | | time.point | Time point | | \`-1 = baseline/before label, 0 = time of label, 1 = \~4 days post label, 2 = \~10 days post label, 3 = \~21 days post label | | material | Sample material | | soil, leaf, root | | siteID | Site abbreviation | | DC = Deer Creek, WC = Willow Creek, TW = Tenalquot Prairie | | site.loc | Site location on latitude gradient | | north, middle, south | | restor.group | Restoration manipulation group | | restored, pasture | | drought.trt | Rain exclusion treatment | | drought, control | | plotID | Plot number | | | | dist.cm | Distance (cm) | cm | | | sci.name | Scientific name | | | | speciesID | Species code | | | | ann.per | Life history strategy | | Annual, Perennial | | grass.forb | Structural group | | Grass, Forb | | dnr.rcvr | Donor/Receiver | | Donor, Receiver | | degree.connect | Degrees of connectivity | Number of plants in the same plot that share at least one ASV with this individual | | | n.fungal.asv | Number of fungal ASVs | Number of fungal ASVs found in the roots of this plant | | | enriched.N | 15N enriched | binary | TRUE/FALSE | | d15N | $\delta ^{15}N | per mil | | | atpct.15N | ^{15}N atom percent | atm % | | | N.per | Percent N content | % | | | NDFL.per | Percent N derived from label | % | | | NDFL.mass | mg N derived from label per g leaf | mg N/g leaf | | | enriched.C | 13C enriched | binary | TRUE/FALSE | | d13C | $\delta ^{13}C | per mil | | | atpct.13C | ^{13}C atom percent | atm % | | | C.per | Percent C content | % | | | CDFL.per | Percent C derived from label | % | | | CDFL.mass | mg C derived from label per g leaf | mg C/g leaf | | | C.N | C:N ratio | | | | iWUE | Intrinsic water-use efficiency | $\mu mol/mol | | ## Sharing/access Information Links to other publicly accessible locations of the data: none Was data derived from another source? No If yes, list source(s): NA