DOI: 10.5061/dryad.sc38s
title: Data from: The role of soil chemistry and plant neighbourhoods in structuring fungal communities in three Panamanian rainforests

description: Fungi play critical roles in ecosystem processes and interact with plant
 communities in mutualistic, pathogenic, and commensal ways. Fungal
 communities are thought to depend on both associated tree communities and
 soil properties. However, the relative importance of the biotic and
 abiotic drivers of soil fungal community structure and diversity in
 lowland tropical forests remains poorly understood. We examined the
 community structure of trees and fungi at different levels of phosphorus
 (0·17–16·3 mg kg−1) in moist tropical forests in Panama. We predicted that
 arbuscular mycorrhizal (AM) fungal composition would be more strongly
 associated with soil properties than with local tree communities while the
 composition of other fungal clades would be more strongly correlated with
 local tree communities than soil properties. We also predicted that fungal
 operational taxonomic unit (OTU) richness would be negatively correlated
 with soil fertility and positively correlated with tree species diversity
 within and among forests. We characterized soil chemistry, fine root
 biomass, and sequenced the ITS1 barcode region to describe fungal
 community composition from 70 soil cores across three 1-ha tropical
 rainforest sites in Panama. The sites vary in soil chemistry, including P,
 and in tree species community composition, but experience similar annual
 rainfall. AM fungal community composition was partially correlated with
 soil chemistry (r = 0·32, P ≤ 0·001), but not with local tree communities,
 while non-AM fungal communities were nearly equally correlated with soil
 chemistry (Partial Mantel test, r = 0·38, P ≤ 0·001) as with tree
 communities (r = 0·36, P ≤ 0·001). Linear models showed that AM OTU
 richness was not explained by any independent variable. For non-AM fungi,
 phosphorus, pH, and soil moisture better predicted OTU richness across all
 cores than other biotic and abiotic factors. Synthesis. Our results show
 that AM fungal structure is driven primarily by soil chemistry. For non-AM
 fungi, soil properties and the local tree community can play a joint role
 in structuring communities. Furthermore, we found that more diverse local
 tree communities did not harbour more fungal species. Our results suggest
 that soil properties act as an environmental filter for both trees and
 fungi, setting the stage for interactions between the two.
description: OTU_TableA table of the number of sequences per sample of all consensus OTU sequences that matched a fungal taxon in the UNITE fungal database (as of 08/22/2016). Columns are fungal taxonomic names from UNITE database and rows are samples. Column 'core' is an internal sample designation during the field collection phase. Site 'p7' in the 'site' column pertains to 'Pipeline,' 'chagres' refers to 'Campo Chagres,' and 'roubik' refers to 'Santa Rita Ridge' site names from the accompanying manuscript.all.new.filtered3_dryad.csvSoil_NutrientsSoil nutrient values listed per sample. 'Core' column refers to an internal designation of samples during the field collection phase and corresponds to 'core' columns in accompanying data files. 'p7' in the 'site' column refers to the 'Pipeline' site, 'chagres' refers to the 'Campo Chagres' site, and 'roubik' refers to the 'Santa Rita Ridge' site from the manuscript.nutrients_final.csvTree_NeighborhoodsA matrix showing the relative abundance in total DBH (mm) of tree species within a 10-m radius of soil samples, per sample. 'Core' column refers to an internal sample designation during the field collection phase and corresponds to 'core' column in other data files. 'p7' in the 'Site' column refers to 'Pipeline,' 'chagres' refers to 'Campo Chagres,' and 'roubik' refers to 'Santa Rita Ridge' site from the manuscript. These data were calculated using tree census data from Condit, R., Pẽrez, R., Aguilar, S. & Lao, S. (2013b) Data from Tree Censuses and Inventories in Panama and are available online at the Smithsonian Tropical Research Institute data repository.vegetation_final.csv