Ecological Archives A016-023-A1

Charles D. Canham, Michael J. Papaik, María Uriarte, William H. McWilliams, Jennifer C. Jenkins, and Mark J. Twery. 2006. Neighborhood analyses of canopy tree competition along environmental gradients in New England forests. Ecological Applications 16:540–554.

Appendix A. Parameter estimates and two-unit support intervals for the most parsimonious models for each of the 14 target tree species.

The tables below report the parameter estimates and two-unit support intervals for the most parsimonious models (i.e., lowest AICcorr in Table 2) for each of the 14 target tree species. Species are identified with acronyms consisting of the first two letters of the genus and the specific epithet. See Table 1 of the manuscript for full names.

TABLE A1. Number of observations (n), goodness of fit (R2), error variance proportionality (1 from Eq. 8), and potential diameter growth (PDG, in mm/yr). Parameters C and D control the shape of the function describing response of a target tree to variation in NCI (Eq. 6).

Species

n

R2

1

PDG

C

D

ABBA

429

0.253

0.667

4.876

21.163

 
     

0.657 - 0.677

4.826 - 4.926

20.663 - 21.663

 

ACRU

930

0.125

0.919

4.138

116.846

 
     

0.909 - 0.929

4.088 - 4.188

113.340 - 118.014

 

ACSA

751

0.214

0.807

5.227

1.943

 
     

0.797 - 0.837

5.175 - 5.384

1.443 - 2.443

 

BEAL

333

0.148

0.770

14.788

529.473

 
     

0.750 - 0.780

14.640 - 14.936

518.884 - 534.768

 

BELE

55

0.268

0.424

3.340

1.776

2.495

     

0.414 - 0.434

3.290 - 3.390

1.276 - 2.276

2.470 - 2.500

BEPA

480

0.148

0.779

2.563

2.553

 
     

0.769 - 0.789

2.513 - 2.613

2.053 - 3.053

 

FAGR

350

0.170

0.617

4.342

4.774

 
     

0.607 - 0.627

4.292 - 4.392

4.274 - 5.274

 

FRAM

134

0.202

0.651

5.187

0.761

 
     

0.631 - 0.661

5.135 - 5.239

0.261 - 1.261

 

PIRU

440

0.195

0.719

4.168

1.574

 
     

0.709 - 0.729

4.118 - 4.218

1.074 - 2.074

 

PIST

501

0.351

1.287

11.777

317.498

 
     

1.248 - 1.300

11.659 - 11.895

314.323 - 320.673

 

POTR

104

0.232

0.639

4.925

492.981

 
     

0.629 - 0.659

4.875 - 5.075

458.472 - 497.911

 

PRSE

53

0.228

0.847

6.713

2.000

 
     

0.837 - 0.877

6.578 - 6.780

1.500 - 2.500

 

QURU

224

0.272

0.613

42.911

527.547

 
     

0.603 - 0.633

42.482 - 43.340

522.271 - 532.822

 

TSCA

425

0.284

0.587

8.128

171.671

 
     

0.577 - 0.617

8.046 - 8.209

166.521 - 173.388

 

 

TABLE A2. If the parameter is listed, then for that species the sensitivity of a target tree to competition varied as a function of target tree DBH (Eq. 7). The and parameters control the scaling of the effects of neighbor size and distance on NCI (Eq. 5). The and parameters determine the effect of target tree size on potential growth (Eq. 2).

Species

ABBA

-0.903

0.000

0.527

0.137

10.989

 

-0.912 - -0.894

0.000 - 0.002

0.522 - 0.559

0.037 - 0.237

10.550 - 11.099

ACRU

-1.535

1.763

0.381

3.163

98.223

 

-1.551 - -1.520

1.746 - 1.816

0.378 - 0.397

3.063 - 200.000

97.241 - 100.000

ACSA

 

1.315

0.506

43.109

1.141

   

1.302 - 1.380

0.486 - 0.511

40.954 - 43.540

1.091 - 1.241

BEAL

-2.000

0.317

0.474

0.001

5.523

 

-2.000 - -1.980

0.313 - 0.393

0.469 - 0.479

0.001 - 0.101

5.467 - 5.578

BELE

 

2.807

0.440

0.001

13.788

   

2.723 - 2.835

0.418 - 0.444

0.001 - 0.101

13.650 - 13.925

BEPA

 

1.194

0.316

17.925

0.865

   

1.182 - 1.230

0.284 - 0.319

17.388 - 18.105

0.815 - 0.915

FAGR

-0.491

0.803

0.363

20.943

0.820

 

-0.501 - -0.486

0.691 - 0.811

0.359 - 0.403

20.734 - 21.781

0.770 - 0.870

FRAM

 

1.930

0.000

40.045

1.129

   

1.660 - 1.950

0.000 - 0.012

39.645 - 40.846

1.079 - 1.179

PIRU

 

1.366

0.543

32.751

0.886

   

1.352 - 1.380

0.538 - 0.548

32.424 - 33.079

0.836 - 0.936

PIST

-1.598

2.084

0.248

0.284

5.846

 

-1.614 - -1.582

2.064 - 2.126

0.240 - 0.250

0.184 - 0.384

5.787 - 5.904

POTR

-2.000

0.731

0.000

195.263

97.838

 

-2.000 - -1.980

0.710 - 0.739

0.000 - 0.002

0.001 - 197.216

96.860 - 100.000

PRSE

 

1.041

0.000

40.749

0.936

   

0.999 - 1.051

0.000 - 0.002

40.342 - 41.564

0.886 - 0.986

QURU

-2.000

1.961

0.203

0.001

6.810

 

-2.000 - -1.980

1.942 - 1.981

0.136 - 0.205

0.001 - 0.101

6.742 - 6.878

TSCA

-1.482

0.493

0.658

0.001

9.736

 

-1.496 - -1.467

0.478 - 0.498

0.651 - 0.678

0.001 - 0.101

9.639 - 9.833

 

TABLE A3.  Parameters controlling variation in potential tree growth along the first 1 or 2 ordination axes, for species for which including site effect terms improved the model.  “Axis 1 Form” and “Axis 2 Form” identify whether the function used was Gaussian (G; Eq. 3) or logistic (L; Eq. 4).

     

Axis 1

Axis 2

Species

Axis 1 Form

Axis 2 Form

X0

Xb

X0

Xb

ABBA

           
             

ACRU

G

G

-2.000

5.849

2.750

4.383

     

-2.000 - -1.920

5.791 - 6.200

2.723 - 2.750

4.333 - 4.433

ACSA

G

G

-2.000

2.406

0.282

1.555

     

-2.000 - -1.980

2.356 - 2.606

0.215 - 0.285

1.505 - 1.705

BEAL

           
             

BELE

           
             

BEPA

           
             

FAGR

 

L

   

2.168

5.493

         

2.146 - 2.211

5.438 - 5.767

FRAM

 

G

   

1.267

1.726

         

1.255 - 1.280

1.676 - 1.776

PIRU

G

 

0.066

1.362

   
     

0.064 - 0.068

1.312 - 1.412

   

PIST

 

G

   

1.081

1.610

         

1.070 - 1.092

1.560 - 1.660

POTR

           
             

PRSE

           
             

QURU

G

L

-1.999

3.443

2.439

-0.388

     

-2.000 - -1.979

3.393 - 3.493

2.415 - 2.537

-0.413 - -0.363

TSCA

G

 

1.996

3.234

   
     

1.976 - 2.000

3.134 - 3.284

   

 

TABLE A4.  Estimated competition coefficients () using the Mixed model, for the 12 species for which that grouping of competitors was the most parsimonious. The Mixed model estimated separate competition coefficients for intraspecific competition and 3 groups of interspecific competitors (weak, intermediate, and strong competitors), grouped based on the magnitude of species-specific competition coefficients estimated in the full model. Table 3 of the manuscript gives the species-specific values of for neighbors of each target tree species used for the grouping. Neighboring species with  values between 0 – 0.33 were grouped as “Weak” competitors.  Species with > 0.33 and <0.67 were grouped as “Intermediate” competitors, and species with > 0.67 were grouped as “Strong” competitors.

Species

Intraspecific competition

Interspecific competitors

Weak

Intermediate

Strong

ABBA

0.357

0.174

0.484

1.000

 

0.353 - 0.360

0.170 - 0.175

0.465 - 0.489

0.990 - 1.000

ACRU

1.000

0.000

0.536

1.000

 

0.960 - 1.000

0.000 - 0.001

0.525 - 0.541

0.990 - 1.000

ACSA

1.000

0.153

0.508

0.763

 

0.990 - 1.000

0.020 - 0.154

0.483 - 0.513

0.702 - 0.771

BEAL

0.599

0.051

0.601

1.000

 

0.593 - 0.605

0.050 - 0.052

0.595 - 0.619

0.990 - 1.000

BELE

1.000

0.000

0.561

0.000

 

0.970 - 1.000

0.000 - 0.001

0.556 - 0.578

0.000 - 0.000

BEPA

0.498

0.000

0.532

1.000

 

0.493 - 0.503

0.000 - 0.001

0.505 - 0.537

0.990 - 1.000

FAGR

0.901

0.568

0.390

1.000

 

0.847 - 0.910

0.562 - 0.574

0.371 - 0.394

0.990 - 1.000

PIST

0.880

0.000

0.606

1.000

 

0.854 - 0.889

0.000 - 0.001

0.600 - 0.679

0.990 - 1.000

POTR

0.667

0.000

0.369

1.000

 

0.660 - 0.714

0.000 - 0.001

0.355 - 0.373

0.940 - 1.000

PRSE

1.000

0.003

0.471

0.246

 

0.920 - 1.000

0.003 - 0.020

0.466 - 0.513

0.000 - 1.000

QURU

1.000

0.000

0.701

1.000

 

0.810 - 1.000

0.000 - 0.001

0.694 - 0.729

0.990 - 1.000

TSCA

1.000

0.000

0.567

0.847

 

0.990 - 1.000

0.000 - 0.001

0.562 - 0.573

0.805 - 0.855



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