Ecological Archives E096-064-A8

Xubing Liu, Rampal S. Etienne, Minxia Liang, Yongfan Wang, and Shixiao Yu. 2015. Experimental evidence for an intraspecific Janzen-Connell effect mediated by soil biota. Ecology 96:662671. http://dx.doi.org/10.1890/14-0014.1

Appendix H. (Multivariate) odds ratio regression between survival log odds ratio and nine characteristic dissimilarities.

Table H1. Results of best-fit multivariate log odds ratio regressions with log odds ratio (field soil treated pots vs. sterile soil pots) as the response variable and the characteristic dissimilarities or the principal components as explanatory variables.

Variable

AICc

R²

Estimate

1 SE of estimate

t

P

Castanopsis fissa

1. Best-fir model with the variable dissimilarities

-33.10

0.230

 

 

 

 

(Intercept)

 

 

-1.144

0.152

-7.5

<0.001

Photosynthetic rate

 

 

0.860

0.328

2.6

0.015

2. Best-fir model with the principal components

-32.11

0.317

 

 

 

 

(Intercept)

 

 

-0.843

0.098

-8.6

<0.001

PC1

 

 

-0.102

0.042

-2.4

0.025

PC4

 

 

0.189

0.135

-1.4

0.177

PC9

 

 

1.420

1.003

1.4

0.172

Canarium album

3. Best-fir model with the variable dissimilarities

-35.70

0.450

 

 

 

 

(Intercept)

 

 

-1.327

0.182

-7.3

<0.001

Spatial distance

 

 

0.551

0.346

1.6

0.127

DBH

 

 

0.619

0.350

1.8

0.093

Wood density

 

 

1.040

0.441

2.4

0.029

Seed mass

 

 

-0.852

0.588

-1.4

0.163

4. Best-fir model with the principal components

-37.71

0.451

 

 

 

 

(Intercept)

 

 

-0.790

0.087

-9.0

<0.001

PC1

 

 

-0.154

0.044

-3.5

0.002

PC6

 

 

0.293

0.179

1.6

0.117

PC8

 

 

0.499

0.249

1.4

0.167

Notes: Log odds ratios were calculated by comparing survival in field soil treated pots vs. sterile soil pots (n = 30 seedlings per treatment). Multivariate log odds ratio regression models were fitted against all the nine characteristic dissimilarities or all the nine principal components, the best-fir model with a lowest AICc value was selected by a backward stepwise algorithm.

 

Table H2. Results of best-fit log odds ratio regressions with log odds ratio (soil filtrate treated pots vs. sterile soil pots) as the response variable and the characteristic dissimilarities or the principal components as explanatory variables.

Variable

AICc

R²

Estimate

1 SE of estimate

t

P

Castanopsis fissa

1. Best-fir model with the variable dissimilarities

-33.57

0.478

 

 

 

 

(Intercept)

 

 

-1.092

0.200

-5.5

<0.001

Genetic distance

 

 

-2.260

1.098

-2.1

0.053

Spatial distance

 

 

1.403

0.547

2.6

0.018

Wood density

 

 

3.268

1.066

3.1

0.006

Seed mass

 

 

-0.985

0.389

-2.5

0.020

2. Best-fir model with the principal components

-31.66

0.437

 

 

 

 

(Intercept)

 

 

-0.875

0.097

-9.0

<0.001

PC1

 

 

-0.115

0.042

-2.7

0.013

PC2

 

 

0.094

0.071

1.3

0.201

PC4

 

 

0.225

0.134

1.7

0.108

PC8

 

 

-1.683

0.908

-1.9

0.079

Canarium album

3. Best-fir model with the variable dissimilarities

-21.58

0.442

 

 

 

 

(Intercept)

 

 

-1.148

0.253

-4.5

<0.001

Genetic distance

 

 

-3.082

1.774

-1.7

0.100

Spatial distance

 

 

3.254

1.693

1.9

0.072

 DBH

 

 

1.134

0.484

2.3

0.031

Photosynthetic rate

 

 

0.965

0.607

1.6

0.130

Wood density

 

 

2.668

1.174

2.3

0.036

Seed mass

 

 

-2.490

1.140

-2.2

0.043

LNC

 

 

-0.856

0.465

-1.8

0.083

4. Best-fir model with the principal components

-25.94

0.405

 

 

 

 

(Intercept)

 

 

-0.811

0.109

-7.4

<0.001

PC1

 

 

-0.131

0.054

-2.4

0.026

PC5

 

 

-0.257

0.164

-1.6

0.133

PC6

 

 

0.356

0.223

1.6

0.126

PC8

 

 

0.725

0.434

1.7

0.111

Notes: Log odds ratios were calculated by comparing survival in soil filtrate treated pots vs. sterile soil pots (n = 30 seedlings per treatment). Multivariate log odds ratio regression models were fitted against all the nine characteristic dissimilarities or all the nine principal components, the best-fir model with a lowest AICc value was selected by a backward stepwise algorithm.

 

 

 

Fig. H1. Odds ratio regression between survival log odds ratio and trait dissimilarities for Castanopsis fissa seedlings. Log odds ratios were calculated by comparing survival in field soil treated pots vs. sterile soil pots (first and third columns) or soil filtrate treated pots vs. sterile soil pots (second and fourth columns) (n = 30 seedlings per treatment). For each trait/variable, the dissimilarity between any two populations was defined as their standardized absolute difference diAB (see Data analysis section for details). Log-transformed survival odds ratios above 0 indicate positive effects and log odds ratios that are significantly lower than 0 indicate negative effects. Best-fit odds ratio regression lines are shown, P values indicate significant departure from no relationship with trait dissimilarities. DBH: diameter at breast height; SLA: specific leaf area, LNC: leaf nitrogen concentration.


 

 

Fig. H2. Odds ratio regression between survival log odds ratio and trait dissimilarities for Canarium album seedlings. Log odds ratios were calculated by comparing survival infield soil treated pots vs. sterile soil pots (first and third columns) or soil filtrate treated pots vs. sterile soil pots (second and fourth columns) (n = 30 seedlings per treatment). For each trait/variable, the dissimilarity between any two populations was defined as their standardized absolute difference diAB (see Data analysis section for details). Log-transformed survival odds ratios above 0 indicate positive effects and log odds ratios that are significantly lower than 0 indicate negative effects. Best-fit odds ratio regression lines are shown, P values indicate significant departure from no relationship with trait dissimilarities. DBH: diameter at breast height; SLA: specific leaf area, LNC: leaf nitrogen concentration.


 

 

Fig. H3. Odds ratio regression between survival log odds ratio and trait dissimilarities measured on seedlings.


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