Table 3 Soil enzymes as affected by N fertilizer and green manures. Data are means ± standard errors.
Dehydrogenase (INTF mg kg−1 24 h−1) | Urease (NH4+-N mg kg−1 4 h−1) | Acid phosphatase (p-nitrophenol mg kg−1 2 h−1) | β-glucosidase (p-nitrophenol mg kg−1 2 h−1) | |
|---|---|---|---|---|
2012 | ||||
Control | 9.61 ± 0.42 cd | 216.73 ± 9.58b | 396.75 ± 1.48d | 207.62 ± 8.33b |
Alfalfa | 13.30 ± 0.30a | 258.72 ± 4.81ab | 451.24 ± 14.08abc | 254.83 ± 9.95a |
Broad bean | 10.86 ± 0.43bc | 237.64 ± 23.28b | 463.5 ± 5.58ab | 251.30 ± 18.19a |
N fertilizer | 9.02 ± 0.50d | 230.05 ± 11.25b | 436.25 ± 4.51c | 193.23 ± 8.79b |
Alfalfa + N | 11.23 ± 0.88b | 296.98 ± 17.42a | 470.26 ± 1.76a | 269.00 ± 14.48a |
Broad bean + N | 10.23 ± 0.38bcd | 248.72 ± 7.14b | 445.52 ± 5.51bc | 247.47 ± 13.70a |
2014 | ||||
Control | 11.50 ± 0.68bc | 193.95 ± 0.90d | 428.35 ± 5.49c | 208.18 ± 12.14bc |
Alfalfa | 13.25 ± 0.83a | 223.57 ± 9.63abc | 451.08 ± 9.48a | 220.96 ± 15.73b |
Broad bean | 11.82 ± 0.50abc | 220.01 ± 6.73bc | 440.77 ± 8.86abc | 264.56 ± 8.73a |
N fertilizer | 10.97 ± 0.46c | 213.09 ± 3.14 cd | 430.43 ± 5.18bc | 182.38 ± 13.44c |
Alfalfa + N | 12.82 ± 0.21ab | 242.85 ± 8.32a | 460.05 ± 3.83a | 261.14 ± 6.51a |
Broad bean + N | 11.56 ± 0.46abc | 239.71 ± 8.91ab | 449.26 ± 1.57ab | 240.82 ± 12.27ab |