Table 2.
Effects of species richness, treatment, and their interactions
| Ecosystem stability |
Ecosystem μ |
Ecosystem σ2 |
Asynchrony |
Evenness |
H′ |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| d.f. | F | P | F | P | F | P | F | P | F | P | F | P | |
| N | 1276 | 42·5 | <0·001 | 609·3 | <0·001 | 138·6 | <0·001 | 7·8 | 0·006 | 0·7 | 0·405 | 4·8 | 0·029 |
| F | 1276 | 2·6 | 0·110 | 1·0 | 0·317 | 1·8 | 0·182 | 5·0 | 0·026 | 0·2 | 0·690 | 0·9 | 0·334 |
| M | 1276 | 5·4 | 0·021 | 3·2 | 0·076 | 7·0 | 0·009 | 8·9 | 0·003 | 1·5 | 0·226 | 0·4 | 0·515 |
| R | 26 276 | 2·3 | 0·001 | 1·8 | 0·011 | 2·6 | <0·001 | 0·8 | 0·739 | 2·3 | 0·001 | 7·1 | <0·001 |
| F × M | 1276 | 0·1 | 0·781 | 1·2 | 0·265 | 0·0 | 0·980 | 0·0 | 0·881 | 0·8 | 0·373 | 0·7 | 0·397 |
| F × R | 22 276 | 0·9 | 0·660 | 0·8 | 0·671 | 0·8 | 0·706 | 1·3 | 0·166 | 1·1 | 0·327 | 1·3 | 0·145 |
| M × R | 18 276 | 1·5 | 0·074 | 2·0 | 0·009 | 1·8 | 0·021 | 1·0 | 0·439 | 1·0 | 0·436 | 1·3 | 0·191 |
| F × M × R | 13 276 | 1·4 | 0·152 | 0·6 | 0·848 | 1·5 | 0·114 | 1·0 | 0·462 | 1·3 | 0·200 | 1·6 | 0·073 |
Results of the three-way ANCOVA (with the treatment × species richness interaction term) for the effects of the rate (N) and the frequency (F) of N addition, mowing (M), species richness (R), and their interactions on the temporal stability of ecosystem above-ground net primary productivity, ecosystem mean (μ), ecosystem variance (σ2), species asynchrony, evenness, and Shannon-diversity (H'), using the rate of N addition as a continuous variable. d.f., degrees of freedom. F- and P-values are given.