This file explains all of the variables in each of the datasets that accompany: OÕKeefe K, Nippert JB, McCulloh KA. 2019. Plant water uptake along a diversity gradient provides evidence for complementarity in hydrological niches. Oikos 10.1111/oik.06529

Code:
ÔOKeefe_et_al_2019_isotope_analyses.RÕ: This file contains isotope model (SIAR and SIBER) analyses.

 ÔOKeefe_et_al_2019_traits_analyses.RÕ: This file contains soil moisture and linear regression analyses.

ÔOKeefe_et_al_2019_isotope_posterior_comparisons.RmdÕ: This file contains comparisons of isotope mixing model posterior distributions.

Isotope_model_data:
ÔPlant_Isotopes_All_1_2.txtÕ: Plant isotope values used in SIAR mixing model measured in 1- and 2-species plots, for all months combined.
Code = grouping code used by SIAR (1: Asclepias tuberosa sampled in 1-species plots, 2: Lespedeza capitata sampled in 1-species plots, 3: Liatris aspera sampled in 1-species plots, 4: Schizachyrium scoparium sampled in 1-species plots, 5: Sorghastrum nutans sampled in 1-species plots, 6: Asclepias tuberosa sampled in 2-species plots, 7: Lespedeza capitata sampled in 2-species plots, 8: Liatris aspera sampled in 2-species plots, 9: Schizachyrium scoparium sampled in 2-species plots, 10: Sorghastrum nutans sampled in 2-species plots)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

ÔPlant_Isotopes_All_4_16.txtÕ: Plant isotope values used in SIAR mixing model measured in 4- and 16-species plots, for all months combined.
Code = grouping code used by SIAR (1: Asclepias tuberosa sampled in 4-species plots, 2: Lespedeza capitata sampled in 4-species plots, 3: Liatris aspera sampled in 4-species plots, 4: Schizachyrium scoparium sampled in 4-species plots, 5: Sorghastrum nutans sampled in 4-species plots, 6: Asclepias tuberosa sampled in 16-species plots, 7: Lespedeza capitata sampled in 16-species plots, 8: Liatris aspera sampled in 16-species plots, 9: Schizachyrium scoparium sampled in 16-species plots, 10: Sorghastrum nutans sampled in 16-species plots)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

'Plant_Isotopes_June_A.txt': Plant isotope values used in SIAR mixing model measured in 1- and 2-species plots, for June samples only.
Code = grouping code used by SIAR (1: Asclepias tuberosa sampled in 1-species plots, 2: Lespedeza capitata sampled in 1-species plots, 3: Schizachyrium scoparium sampled in 1-species plots, 4: Sorghastrum nutans sampled in 1-species plots, 5: Asclepias tuberosa sampled in 2-species plots, 6: Lespedeza capitata sampled in 2-species plots, 7: Schizachyrium scoparium sampled in 2-species plots, 8: Sorghastrum nutans sampled in 2-species plots)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

'Plant_Isotopes_June_B.txt': Plant isotope values used in SIAR mixing model measured in 4- and 16-species plots, for June samples only.
Code = grouping code used by SIAR (1: Asclepias tuberosa sampled in 4-species plots, 2: Lespedeza capitata sampled in 4-species plots, 3: Schizachyrium scoparium sampled in 4-species plots, 4: Sorghastrum nutans sampled in 4-species plots, 5: Asclepias tuberosa sampled in 16-species plots, 6: Lespedeza capitata sampled in 16-species plots, 7: Schizachyrium scoparium sampled in 16-species plots, 8: Sorghastrum nutans sampled in 16-species plots)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

'Plant_Isotopes_July_A.txt': Plant isotope values used in SIAR mixing model measured in 1- and 2-species plots, for July samples only.
Code = grouping code used by SIAR (same code as in ÔSamples_All_1_2_corrected.txtÕ)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

'Plant_Isotopes_July_B.txt': Plant isotope values used in SIAR mixing model measured in 4- and 16-species plots, for June samples only.
Code = grouping code used by SIAR (same code as in ÔSamples_All_4_16_corrected.txtÕ)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

'Plant_Isotopes_Aug_A.txt': Plant isotope values used in SIAR mixing model measured in 1- and 2-species plots, for August samples only.
Code = grouping code used by SIAR (same code as in ÔSamples_All_1_2_corrected.txtÕ)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

'Plant_Isotopes_Aug_B.txt': Plant isotope values used in SIAR mixing model measured in 4- and 16-species plots, for August samples only.
Code = grouping code used by SIAR (same code as in ÔSamples_All_4_16_corrected.txtÕ)
dD = deuterium value of water sample in per mil
d18O = heavy oxygen value of water sample in per mil

ÔSource_All.txtÕ: Source isotope values used in SIAR mixing models for all months combined.
Source = isotope sources for mixing model (Shallow, Deep, Snow)
MeandD = mean deuterium value of water source in per mil
SDdD = standard deviation of deuterium source
Meand18O = mean d18O value of water source in per mil
SDd18O = standard deviation of d18O source

ÔJune_Source.txtÕ: Source isotope values used in SIAR mixing models for June samples only.
Source = isotope sources for mixing model (Shallow, Deep, Snow)
MeandD = mean deuterium value of water source in per mil
SDdD = standard deviation of deuterium source
Meand18O = mean d18O value of water source in per mil
SDd18O = standard deviation of d18O source

ÔJuly_Source.txtÕ: Source isotope values used in SIAR mixing models for July samples only.
Source = isotope sources for mixing model (Shallow, Deep, Snow)
MeandD = mean deuterium value of water source in per mil
SDdD = standard deviation of deuterium source
Meand18O = mean d18O value of water source in per mil
SDd18O = standard deviation of d18O source

ÔAug_Source.txtÕ: Source isotope values used in SIAR mixing models for August samples only.
Source = isotope sources for mixing model (Shallow, Deep, Snow)
MeandD = mean deuterium value of water source in per mil
SDdD = standard deviation of deuterium source
Meand18O = mean d18O value of water source in per mil
SDd18O = standard deviation of d18O source

ÔTEFdata.txtÕ: Trophic enrichment factor (TEF) data file.
Source = isotope sources for mixing model (Shallow, Deep, Snow)
MeandD = mean TEF of deuterium water source (0=no TEF)
SDdD = standard deviation of deuterium TEF (0=no TEF)
Meand18O = mean TEF of d18O water source (0=no TEF)
SDd18O = standard deviation of d18O TEF (0=no TEF)

ÔIsotope_Data_SIBER.csvÕ: Raw isotope data formatted for SIBER analyses.
iso1 = deuterium value of water sample in per mil
iso2 = heavy oxygen value of water sample in per mil
group = species group code for SIBER (1: Asclepias tuberosa, 2: Lespedeza capitata, 3: Liatris aspera, 4: Schizachyrium scoparium, 5: Sorghastrum nutans)
community = diversity group code for SIBER (1: 1-species, 2: 2-species, 3: 4-species, 4: 16-species)

Isotope_posterior_analysis_data:
ÔIsotope_Posterior_All_1_2 .txtÕ: Output from SIAR mixing model that included 1- and 2-species plots, for all months combined (i.e., model that used ÔPlant_Isotopes_All_1_2.txtÕ and ÔSource_All.txtÕ data files). This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file include:

ShallowG1 = posterior distribution of proportional 5cm water use by group 1 in SIAR analysis
DeepG1= posterior distribution of proportional 35cm water use by group 1 in SIAR analysis
SnowG1= posterior distribution of proportional deep water use by group 1 in SIAR analysis
SD1G1 = residual error associated with dD for group 1 in SIAR analysis 
SD2G1 = residual error associated with d18O for group 1 in SIAR analysis 

ShallowG2 = posterior distribution of proportional 5cm water use by group 2 in SIAR analysis
DeepG2= posterior distribution of proportional 35cm water use by group 2 in SIAR analysis
SnowG2= posterior distribution of proportional deep water use by group 2 in SIAR analysis
SD1G2 = residual error associated with dD for group 2 in SIAR analysis 
SD2G2 = residual error associated with d18O for group 2 in SIAR analysis 

ShallowG3 = posterior distribution of proportional 5cm water use by group 3 in SIAR analysis
DeepG3 = posterior distribution of proportional 35cm water use by group 3 in SIAR analysis
SnowG3 = posterior distribution of proportional deep water use by group 3 in SIAR analysis
SD1G3 = residual error associated with dD for group 3 in SIAR analysis 
SD2G3 = residual error associated with d18O for group 3 in SIAR analysis 

ShallowG4 = posterior distribution of proportional 5cm water use by group 4 in SIAR analysis
DeepG4 = posterior distribution of proportional 35cm water use by group 4 in SIAR analysis
SnowG4 = posterior distribution of proportional deep water use by group 4 in SIAR analysis
SD1G4 = residual error associated with dD for group 4 in SIAR analysis 
SD2G4 = residual error associated with d18O for group 4 in SIAR analysis 

ShallowG5 = posterior distribution of proportional 5cm water use by group 5 in SIAR analysis
DeepG5 = posterior distribution of proportional 35cm water use by group 5 in SIAR analysis
SnowG5 = posterior distribution of proportional deep water use by group 5 in SIAR analysis
SD1G5 = residual error associated with dD for group 5 in SIAR analysis 
SD2G5 = residual error associated with d18O for group 5 in SIAR analysis 

ShallowG6 = posterior distribution of proportional 5cm water use by group 6 in SIAR analysis
DeepG6 = posterior distribution of proportional 35cm water use by group 6 in SIAR analysis
SnowG6 = posterior distribution of proportional deep water use by group 6 in SIAR analysis
SD1G6 = residual error associated with dD for group 6 in SIAR analysis 
SD2G6 = residual error associated with d18O for group 6 in SIAR analysis 

ShallowG7 = posterior distribution of proportional 5cm water use by group 7 in SIAR analysis
DeepG7 = posterior distribution of proportional 35cm water use by group 7 in SIAR analysis
SnowG7 = posterior distribution of proportional deep water use by group 7 in SIAR analysis
SD1G7 = residual error associated with dD for group 7 in SIAR analysis 
SD2G7 = residual error associated with d18O for group 7 in SIAR analysis 

ShallowG8 = posterior distribution of proportional 5cm water use by group 8 in SIAR analysis
DeepG8 = posterior distribution of proportional 35cm water use by group 8 in SIAR analysis
SnowG8 = posterior distribution of proportional deep water use by group 8 in SIAR analysis
SD1G8 = residual error associated with dD for group 8 in SIAR analysis 
SD2G8 = residual error associated with d18O for group 8 in SIAR analysis 

ShallowG9 = posterior distribution of proportional 5cm water use by group 9 in SIAR analysis
DeepG9 = posterior distribution of proportional 35cm water use by group 9 in SIAR analysis
SnowG9 = posterior distribution of proportional deep water use by group 9 in SIAR analysis
SD1G9 = residual error associated with dD for group 9 in SIAR analysis 
SD2G9 = residual error associated with d18O for group 9 in SIAR analysis 

ShallowG10 = posterior distribution of proportional 5cm water use by group 10 in SIAR analysis
DeepG10 = posterior distribution of proportional 35cm water use by group 10 in SIAR analysis
SnowG10 = posterior distribution of proportional deep water use by group 10 in SIAR analysis
SD1G10 = residual error associated with dD for group 10 in SIAR analysis 
SD2G10 = residual error associated with d18O for group 10 in SIAR analysis 

ÔIsotope_Posterior_All_4_16.txtÕ: Output from SIAR mixing model that included 4- and 16-species plots, for all months combined. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_All_4_16.txtÕ and ÔSource_All.txtÕ data files.

ÔIsotope_Posterior_June_A.txtÕ: Output from SIAR mixing model that included 1- and 2-species plots, for June samples only. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_June_A.txtÕ and ÔJune_Source.txtÕ data files.

ÔIsotope_Posterior_June_B.txtÕ: Output from SIAR mixing model that included 4- and 16-species plots, for June samples only. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_June_B.txtÕ and ÔJune_Source.txtÕ data files.

ÔIsotope_Posterior_July_A.txtÕ: Output from SIAR mixing model that included 1- and 2-species plots, for July samples only. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_July_A.txtÕ and ÔJuly_Source.txtÕ data files.

ÔIsotope_Posterior_July_B.txtÕ: Output from SIAR mixing model that included 4- and 16-species plots, for July samples only. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_July_B.txtÕ and ÔJuly_Source.txtÕ data files.

ÔIsotope_Posterior_Aug_A.txtÕ: Output from SIAR mixing model that included 1- and 2-species plots, for August samples only. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_Aug_A.txtÕ and ÔAug_Source.txtÕ data files.

ÔIsotope_Posterior_Aug_B.txtÕ: Output from SIAR mixing model that included 4- and 16-species plots, for August samples only. This file is used with the code included in ÔOKeefe_et_al_2019_isotope_posterior_comparisons.Rmd.Õ Columns within this file are the same as described for ÔIsotope_Posterior_All_1_2 .txtÕ but refer to the SIAR output produced with ÔPlant_Isotopes_Aug_B.txtÕ and ÔAug_Source.txtÕ data files.

Raw_data:
ÔCC_soil moisture_data.csvÕ: 2017 growing season soil moisture data.
Date = month, day, and year of sampling day
Month = sampling month (June, July, August)
DOY = day of year
Diversity = diversity treatment (1, 2, 4, and 16 species)
Plot = plot ID number
Replicate = replicate measurement within a plot
VWC_PERC = percent volumetric water content

ÔCC_isotope_anpp2017_data.csvÕ: Physiology data and shift in isotope source comparisons.
Species = species sampled (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium
scoparium, SORNU = Sorghastrum nutans)
Diversity = diversity treatment (1, 2, 4, and 16 species)
Biomass = species average biomass in grams
Observed_Expected = biomass overyielding
Photo = net photosynthesis in ?mol CO2 m2s-1 measured in July
Cond = stomatal conductance in mol CO2 m2s-1 measured in July
Trmmol = transpiration in mmol CO2 m2s-1 measured in July
PD_WP = predawn leaf water potential in MPa measured in July
MD_WP = midday leaf water potential in MPa measured in July
Shallow_Diff_fromMono_July = the difference in 5cm source water used between monocultures and higher diversity treatments, measured in July
Deep_Diff_fromMono_July = the difference in 35cm source water used between monocultures and higher diversity treatments, measured in July
Snow_Diff_fromMono_July = the difference in snow source water (= deep water proxy) used between monocultures and higher diversity treatments, measured in July

CC_2017_climate_data.csv: 2017 growing season climate data.
Date = month, day, and year
DOY = day of year
MaxTemp_C = daily maximum temperature in Celsius
MinTemp_C = daily maximum temperature in Celsius
Precip_mm = daily total precipitation in mm

CC_phys_data.csv: All physiology data.
Date = month, day, and year of sampling day
Month = sampling month (June, July, August)
DOY = day of year
Species = species sampled (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium
scoparium, SORNU = Sorghastrum nutans)
Diversity = diversity treatment (1, 2, 4, and 16 species)
Photo = net photosynthesis in ?mol CO2 m2s-1
Cond = stomatal conductance in mol CO2 m2s-1
Trmmol = transpiration in mmol CO2 m2s-1
PD_WP = predawn leaf water potential in MPa
MD_WP = midday leaf water potential in MPa
WUE = instantaneous water use efficiency (=Photo/Trmmol)

CC_raw_isotope_data: Raw isotope data with treatment factor labels.
Plot_ID = plot ID number
Month = sampling month (June, July, August)
Species = species sampled (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium scoparium, SORNU = Sorghastrum nutans)
Sample_Type = type of sample (plant, soil, snow)
Diversity = diversity treatment (1, 2, 4, and 16 species)
Depth = soil depth sampled (5 and 35 cm)
dD = ?D in per mil
d18O = ?18O

Results:
ÔSIAR_posterior_summary.csvÕ: Summary of SIAR output.
Species = species sampled (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium scoparium, SORNU = Sorghastrum nutans)
Diversity = diversity treatment (1, 2, 4, and 16 species)
Month = sampling month (June, July, August)
Source = isotope mixing model source (Shallow, Deep, Snow)
Mean = posterior distribution mean 
Difference = difference between posterior distribution mean of monocultures and higher diversity plots
Median = posterior distribution median
Low_90CI = 90% credible interval lower limit
High_90CI = 90% credible interval upper limit

ÔSIBER_Layman_results.csvÕ: Summary of SIBER Layman output.
Community = diversity treatment (1, 2, 4, and 16 species)
TA_Mean = mean convex hull area
TA_Mode = convex hull area mode
TA_Median = median convex hull area
CI_90_lower = 90% credible interval lower limit
CI_90_lower = 90% credible interval upper limit

ÔSIBER_niche_overlap_results.csvÕ: Summary of SIBER niche overlap output.
Community = diversity treatment (1, 2, 4, and 16 species).
Species1 = species 1 in pairwise comparison (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium scoparium, SORNU = Sorghastrum nutans)
Species2 = species 2 in pairwise comparison (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium scoparium, SORNU = Sorghastrum nutans)
Perc_Overlap_Bayes_Mean = Mean Bayesian percent niche overlap between species pair
Perc_Overlap_Bayes_Mode = Bayesian percent niche overlap mode between species pair
Perc_Overlap_Bayes_Median = Median Bayesian percent niche overlap between species pair
CI_90_lower = 90% credible interval lower limit
CI_90_lower = 90% credible interval upper limit

ÔSIBER_SEAB_results.csvÕ: Summary of SIBER SEAB output.
Species = species sampled (ASCTU = Asclepias tuberosa, LESCA = Lespedeza capitata, LIAAS = Liatris aspera, SCHSC = Schizachyrium scoparium, SORNU = Sorghastrum nutans)
Diversity = diversity treatment (1, 2, 4, and 16 species)
SEAB_Mean = mean Bayesian standard ellipse area
SEAB_Mode = Bayesian standard ellipse area mode
SEAB_Median = median Bayesian standard ellipse area
CI_90_lower = 90% credible interval lower limit
CI_90_lower = 90% credible interval upper limit

ÔspeciesComparisons_90CI.csvÕ: Summary of species pairwise comparisons of isotope mixing model posterior distributions, for all months.
diversity = diversity treatment (monoculture, 2sp, 4sp, 16sp)
depth = mixing model source (shallow, deep, snow)
species1 = group number of first species compared in corresponding SIAR analysis
species2 = group number of second species compared in corresponding SIAR analysis
columnname1 = mixing model source + group number of first species
columnname2 = mixing model source + group number of second species
diff.posteriorpositive = proportion of the compared distributions that are different
diff.interval90low = 90% credible interval lower limit of difference between pairwise comparison
diff.interval90high = 90% credible interval upper limit of difference between pairwise comparison
diff.median = median difference between pairwise comparison
twofolddiff.posteriorpositive = proportion of binary logarithm of the relative difference between the posterior distributions being compared that are positive
twofolddiff.interval90low = 90% credible interval lower limit of binary logarithm of the relative difference between compared posterior distributions
twofolddiff.interval90high = 90% credible interval upper limit of binary logarithm of the relative difference between compared posterior distributions
twofolddiff.median = median binary logarithm of the relative difference between compared posterior distributions

ÔdiversityComparisons_90CI.csvÕ: Summary of diversity pairwise comparisons of isotope mixing model posterior distributions, for all months.
depth = mixing model source (shallow, deep, snow)
species = group number from SIAR analysis of monoculture species in comparison

ID_num = order of groups from SIAR analysis of diverse species comparsion
diversity = diversity treatment (monoculture, 2sp, 4sp, 16sp)
mononame = group number from SIAR analysis of monoculture species in comparison
diversename = group number from SIAR analysis of diverse species in comparison
diff.posteriorpositive = proportion of the compared distributions that are different
diff.interval90low = 90% credible interval lower limit of difference between pairwise comparison
diff.interval90high = 90% credible interval upper limit of difference between pairwise comparison
diff.median = median difference between pairwise comparison
twofolddiff.posteriorpositive = proportion of binary logarithm of the relative difference between the posterior distributions being compared that are positive
twofolddiff.interval90low = 90% credible interval lower limit of binary logarithm of the relative difference between compared posterior distributions
twofolddiff.interval90high = 90% credible interval upper limit of binary logarithm of the relative difference between compared posterior distributions
twofolddiff.median = median binary logarithm of the relative difference between compared posterior distributions

ÔJune_speciesComparisons_90CI.csvÕ: Summary of species pairwise comparisons of isotope mixing model posterior distributions, for June samples only. Column descriptions are the same as described for ÔspeciesComparisons_90CI.csv.Õ

ÔJune_diversityComparisons_90CI.csvÕ: Summary of diversity pairwise comparisons of isotope mixing model posterior distributions, for June samples only. Column descriptions are the same as described for ÔdiversityComparisons_90CI.csv.Õ

ÔJuly_speciesComparisons_90CI.csvÕ: Summary of species pairwise comparisons of isotope mixing model posterior distributions, for July samples only. Column descriptions are the same as described for ÔspeciesComparisons_90CI.csv.Õ

ÔJuly_diversityComparisons_90CI.csvÕ: Summary of diversity pairwise comparisons of isotope mixing model posterior distributions, for July samples only. Column descriptions are the same as described for ÔdiversityComparisons_90CI.csv.Õ

ÔAug_speciesComparisons_90CI.csvÕ: Summary of species pairwise comparisons of isotope mixing model posterior distributions, for August samples only. Column descriptions are the same as described for ÔspeciesComparisons_90CI.csv.Õ

ÔAug_diversityComparisons_90CI.csvÕ: Summary of diversity pairwise comparisons of isotope mixing model posterior distributions, for August samples only. Column descriptions are the same as described for ÔdiversityComparisons_90CI.csv.Õ


