Clone-Specific Response in Leaf Nitrate Reductase Activity among Unrelated Hybrid Poplars in relation to Soil Nitrate Availability

Table 3

Nitrification and ammonification rates measured during a 24 days period at the two riparian sites (July 17–August 9, 2007). Nitrate and ammonium concentrations at the beginning (initial) and at the end (final) of the in situ incubation period are also presented.

Sites	NO3^− initial; (mg kg^−1)	NO3^− final; (mg kg^−1)	Nitrification rate; (mg kg^−1 24 d^−1)	NH4^+ initial; (mg kg^−1)	NH4^+ final; (mg kg^−1)	Ammonification rate; (mg kg^−1 24 d^−1)
Bromptonville	5.07	16.95	11.87	1.23	0.29	−0.93
Magog	3.13	6.29	3.15	2.92	2.71	−0.21
SE	0.38	1.76	1.55	0.26	0.30	—
𝑃<	0.01	0.001	0.001	0.001	0.001	NS