Ecological Archives E087-091-A2

David G. Jenkins. 2006. In search of quorum effects in metacommunity structure: species co-occurrence analyses. Ecology 87:1523–1531.

Appendix B. Species co-occurrence analysis results. Temporal-spatial classes correspond to one of the four temporal-spatial categories (Table 1 of text) and systems correspond to Appendix A. Systems differed in sample design, which determined the null model used (Gotelli 2000). Each analysis tested the calculated C-score against random distributions obtained with 5000 iterations, and obtained a standardized effect score (SES) with an associated confidence level (P). The effect of weighted analyses relative to unweighted analyses were evaluated by the change in SES (ΔSES). The additional effect of study scale was evaluated by regression, and residuals were evaluated as approximating a Z distribution (see Methods for further details).

 
       

Unweighted analyses

Weighted analyses

  

Study scale : area-weighted SES relationship
       
 

Temporal-spatial class

System

Sample design

C-score

SES

P

Factor

SES

P

Δ SES

Residual

Approx. P

Further Δ SES
 

1. Early local

A

Sample

1.24

0.80

0.24

area

 2.77

0.002

+1.97

  

1.21

n.s.

-0.76
 

B

Island

2.43

1.45

0.13

2o production

 1.82

0.019

+0.371

  

- -

- -

- -
 

C

Island

18.56

14.18

<0.001

area

hydroperiod

 5.12

-6.24

<0.001

1.000

-9.06

-20.42

  

-10.62

- -

n.s.

- -

-1.56

- -
 

D

Island

0.51

1.60

0.07

area

days connected

-1.00

-2.55

0.84

0.99

-2.60

-3.55

  

-3.32

- -

n.s.

- -

-0.72

- -
 

E

Sample

0.70

-0.06

0.63

area

 1.95

0.034

+2.01

  

0.39

n.s.

-1.62

2. Early regional

A

Island

5.57

5.26

<0.001

latitude

-14.82

1.000

-20.64

  

- -

- -

- -
 

B

Sample

48.62

0.57

0.30

area

22.18

<0.001

+21.61

  

4.90

<0.001

-16.71
 

C

Island

2.30

2.14

0.032

area

connectivity

-0.27

 8.80

0.608

<0.001

-2.41

+6.66

  

-5.28

- -

n.s.

- -

-2.87

- -
 

D

Sample

8.63

2.11

0.007

area

14.78

<0.001

+12.67

  

3.25

<0.001

-9.42
 

E

Island

5.66

0.59

0.253

area

regional S

 1.61

-0.51

0.052

0.71

+1.06

-1.07

  

-8.00

n.s.

–9.06

3. Late local

A

Island

3.69

1.66

0.071

hydroperiod

-4.82

1.000

-6.48

  

- -

- -

- -
 

B

Island

0.72

-0.40

0.640

salinity

area

-1.34

 0.22

0.903

0.450

-0.94

+0.62

  

- -

-1.72

- -

n.s.

- -

-2.34
 

C

Island

0.55

1.00

0.154

area

 4.55

<0.001

+3.55

  

1.84

n.s.

-1.71
 

D

Island

0.48

0.60

0.237

area

 6.47

<0.001

+5.87

  

4.91

<0.001

-0.96
 

E

Sample

2.35

0.78

0.23

area

 3.87

<0.001

+3.09

  

0.01

n.s.

-3.08

4. Late regional

A

Island

74.56

4.72

<0.001

area

max. depth

hydroperiod

43.15

16.34

-1.70

<0.001

<0.001

  0.948

+29.51

+2.70

-15.34

  

6.70

- -

- -

<0.001

- -

- -

-22.81

- -

- -
 

B

Island

19.54

10.00

<0.001

salinity

area

19.04

15.39

<0.001

<0.001

+9.04

+5.39

  

- -

-3.42

- -

n.s.

- -

-8.81
 

C

Sample

75.53

-15.37

1.00

area

39.13

<0.001

+54.50

  

-9.59

n.s.

-64.09
 

D

Island

20.67

8.55

<0.001

area

50.65

<0.001

+42.10

  

28.39

<0.001

-13.71
 

E

Sample

24.16

-0.13

0.57

area

11.07

<0.001

+11.20

  

-9.66

n.s.

-20.86

LITERATURE CITED

Gotelli, N. J. 2000. Null model analysis of species co-occurrence patterns. Ecology 81:2606–2621.

[Back to E087-091]