TABLE 2.
Plant community characteristics (mean ± SE) in different treatments and the results of repeated measure ANOVA (F-value and degrees of freedom) for the effects of the fertilization and shade on plant community characteristics.
| Plant variables | Community characteristics in different treatments | Summary of the results of repeated measure ANOVA | |||||||||
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| Control | Fertilization (F) | Shade (S) | F+S | Year (Y) | Fertilization (F) | Shade (S) | Y × F | Y × S | F × S | Y × F × S | |
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| d.f. | 4 | 1 | 1 | 4 | 4 | 1 | 4 | ||||
| Species richness | 28.35 ± 0.61a | 20.98 ± 1.00b | 18.75 ± 0.88b | 11.03 ± 0.67c | 53.27*** | 161.32*** | 270.42*** | 7.22*** | 2.06ns | 0.09ns | 10.60*** |
| Shannon–Weiner index | 2.89 ± 0.03a | 2.58 ± 0.05b | 2.55 ± 0.05b | 1.89 ± 0.06c | 49.48*** | 172.13*** | 189.92*** | 14.65*** | 7.19*** | 21.38*** | 6.20*** |
| Number of individual | 199.0 ± 5.9a | 132.5 ± 8.9b | 83.7 ± 3.6c | 55.5 ± 2.8d | 76.31*** | 114.21*** | 470.80*** | 5.28** | 19.08*** | 18.71*** | 7.17*** |
| Aboveground biomass | 100.7 ± 3.6b | 154.1 ± 5.3a | 50.1 ± 1.4d | 69.3 ± 2.5c | 7.39*** | 202.37*** | 705.82*** | 2.87* | 5.35** | 44.72*** | 3.45* |
| Belowground biomass | 736.1 ± 50.7a | 745.1 ± 36.3a | 414.8 ± 23.0b | 332.1 ± 25.0b | – | 1.08ns | 106.95*** | – | – | 1.67ns | – |
| Root:Shoot ratio | 7.71 ± 0.60a | 4.32 ± 0.34b | 8.00 ± 1.04a | 7.66 ± 0.63a | – | 7.12* | 6.75* | – | – | 4.76* | – |
| SRA (Gramineae) | 22.82 ± 1.20d | 43.90 ± 2.32b | 34.05 ± 1.93c | 55.41 ± 2.54a | 21.34*** | 190.01*** | 54.56*** | 3.82** | 7.32*** | 0.01ns | 20.68*** |
| SRA (Non-Gramineae) | 77.18 ± 1.20a | 56.10 ± 2.32c | 65.95 ± 1.93b | 44.59 ± 2.54d | 21.34*** | 190.02*** | 54.56*** | 3.82** | 7.32*** | 0.01ns | 20.68*** |
| SRA (Fabaceae) | 11.96 ± 0.88a | 4.58 ± 0.75b | 1.34 ± 0.33c | 0.21 ± 0.10c | 6.45** | 50.23*** | 155.50*** | 2.08ns | 2.42ns | 50.17*** | 3.94* |
| SRA (Cyperaceae) | 12.41 ± 0.88a | 6.86 ± 0.99b | 5.65 ± 1.21bc | 2.95 ± 0.82c | 27.83*** | 21.71*** | 36.41*** | 1.40ns | 3.66* | 38.42*** | 2.96* |
Community characteristics were collected and calculated with the data (n = 40) across 5 experimental years (2008–2012) except for that belowground biomass and root:shoot ratio were collected and calculated using the data (n = 8) from the last year of the experiment (2012). Significant differences of each community characteristic among treatments were determined using the least-significant difference (LSD) test (P ≤ 0.05) and indicated by different letters. The value of species richness and number of individuals are numbers per 0.25 m2 (a quadrat area), and biomass is denoted in grams per 0.25 m2. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001; ns, not significant. SRA, species relative abundance; d.f., degree of freedom.