Ecological Archives E089-012-A1

Jennifer A. Lau, Joachim Strengbom, Laurie R. Stone, Peter B. Reich, and Peter Tiffin. 2008. Direct and indirect effects of CO2, nitrogen, and community diversity on plant–enemy interactions. Ecology 89:226–236.

Appendix A. Summary of results for an ANCOVA testing the effects of CO2, N addition, diversity, and plant traits on amounts of damage from four classes of natural enemies.

TABLE A1. ANCOVA of the effects of the CO2, N, and diversity treatments and three plant traits: height, pubescence (“pub”), and specific leaf area (SLA), on the three classes of herbivores.


Source

Generalist

P. laevigatus

Tortriedon sp.

Disease


CO2

0.02

0.44

0.24

0.00

N

0.47

0.02

0.00

2.35

CO2 × N

0.00

0.01

0.07

2.68

Div

18.38****

9.34**

0.26

5.80*

CO2 × Div

0.04

0.60

1.10

5.95*

N × Div

0.00

0.64

0.38

3.73

CO2 × N × Div

0.03

1.43

1.38

0.98

Height

7.95**

1.59

0.01

9.16**

Ht × CO2

0.26

0.10

0.42

0.08

Ht × N

0.66

0.01

0.03

0.90

Ht × Div

8.56**

3.21

0.24

0.03

Height2

11.94***

3.87*

0.15

4.17*

Pub

0.04

4.08*

0.30

0.65

Pub × CO2

0.17

1.04

0.27

1.36

Pub × N

0.63

0.57

0.90

0.77

Pub × Div

1.42

11.19***

0.73

1.62

Pub2

0.87

4.40*

0.56

2.57

SLA

0.99

2.36

2.45

1.91

SLA *CO2

0.39

3.95*

0.14

0.01

SLA *N

3.63

0.93

0.01

3.94*

SLA *Div

0.87

0.23

0.95

1.58

SLA2

4.40*

0.60

1.87

1.84


   Notes: For the herbivore classes, F values are presented, and denominator degrees of freedom ranged from 197–546. For disease, chi-square values are presented from the logistic ANCOVA. Significance is indicated as follows: * < 0.05, ** < 0.01, *** < 0.001, **** < 0.0001.



[Back to E089-012]