Table 1: Soil physicochemical properties and microbial abundance data reported as means and standard errors.

DateSitePlantSoil moisture (%)Redox (mV)pHOrganic matter (%)C : N ratioBacterial abundanceDenitrifier abundance

November 2011RiceReference soil66 (8)b−15 (3)b6.6 (0.5)16 (4)B15.7 (1.0)A230 (74)9.0 (3.5)C
Juncus46 (2)c276 (60)a6.9 (0.3)6 (1)C15.5 (0.7)A378 (59)22.1 (1.4)B
Peltandra76 (2)ab−42 (12)b7.3 (0.5)21 (1)A15.1 (1.3)AB232 (42)16.3 (2.2)B
Typha78 (2)ab2 (22)b7.8 (0.1)25 (2)A13.8 (0.5)B417 (81)42.0 (6.5)A
Overall67 (4)55 (36)7.2 (0.2)17 (2)15.0 (0.4)314 (37)22.3 (3.6)
JamesReference soil80 (1)ab77 (17)6.0 (0.1)18 (2)B15.7 (0.8)A160 (40)4.8 (0.6)C
Juncus84 (1)a88 (34)6.1 (0.1)15 (2)C16.3 (0.4)A101 (27)12.5 (5.8)B
Peltandra81 (1)ab−3 (25)5.8 (0.1)26 (2)A14.9 (0.3)AB153 (38)24.6 (7.4)B
Typha78 (3)b−8 (35)6.0 (0.1)24 (2)A13.1 (0.6)B486 (162)114.5 (47.4)A
Overall81 (1)39 (17)6.0 (0.0)21 (1)15.0 (0.4)189 (60)39.1 (15.7)

June 2012RiceReference soil55 (3)B2 (40)B5.3 (0.2)b13 (1)A13.9 (0.7)B5 (1)C0.6 (0.2)C
Juncus39 (6)C321 (45)A4.8 (0.1)c9 (2)B19.4 (2.4)A39 (13)A2.1 (0.8)B
Peltandra56 (1)AB−29 (34)B5.7 (0.1)ab13 (2)A15.6 (0.6)B15 (2)B5.9 (0.9)B
Typha62 (2)A16 (40)B5.8 (0.0)a14 (1)A13.8 (1.0)B13 (4)B6.3 (0.4)A
Overall53 (3)77 (37)5.4 (0.1)12 (1)15.7 (0.8)18 (4)3.7 (0.6)
JamesReference soil62 (5)B−61 (31)B6.2 (0.1)b15 (2)A13.2 (0.5)B21 (7)C12.8 (4.3)C
Juncus37 (3)C210 (21)A6.6 (0.1)a10 (2)B16.1 (1.0)A129 (25)A70.8 (22.0)B
Peltandra70 (2)AB−37 (20)B6.6 (0.1)a24 (2)A12.9 (0.4)B63 (11)B63.8 (16.1)B
Typha75 (2)A−37 (19)B6.7 (0.1)a24 (2)A12.4 (0.3)B55 (14)B65.6 (20.2)A
Overall61 (4)11 (26)6.5 (0.1)18 (2)13.6 (0.4)67 (12)53.2 (9.5)

Each sampling date was analyzed using a two-factor ANOVA testing for site and plant effects. Whenever a significant site-by-plant interaction was obtained (), each site was reanalyzed separately, and Tukey’s HSD post hoc tests are reported using lowercase letters to distinguish plant effects at each location. In cases where the interaction effect was not significant, main effects are reported using uppercase letters (Tukey’s) for differences across plant types, and †/‡overall site effects. Units for abundance data are (×106) gene copies gDW soil−1.