ISSN: 0024-1148 Russian Journal of Forest Science. 2012, No. 1, pp. 65-71
| NITROGEN MINERALIZATION IN SOIL OF A HIGHLY PRODUCTIVE SOUTHERN TAIGA BIRCH FOREST |
| Razgulin S.M. Institute of Forest Science, Russian Academy of Sciences (ILAN): Sovetskaya st. 21, Uspenskoe village, Moscow Oblast, 143030 |
E-mail: root@ilan.ras.ru |
Received: 28 april 2010
The nitrogen mineralization in the A0-A1 (0-6 cm), A1 (6-11 cm), and A2 (11-21 cm) horizons of a Betuletum oxalidosum measured from May 21 to November 2, 2009 was 6.7 ± 0.9, 3.0 ± 0.4, and 5.5 ± 0.6 g N m-2; the nitrifi cation productivity was 0.4 ± 0.1, 1.1 ± 0.2, and 1.4 ± 0.1 g N m-2, respectively. A total of 15.2±1.1 g N m-2 (150 kg N ha-1) was mineralized in the 0- to 21- cm soil layer. The soil temperature and moisture correlated to the activity of ammonifi cation and ammonium accumulation in the A0-A1 and A1 horizons. The joint effect of soil temperature and moisture contolled the nitrifi cation activity in the A2 horizon and seasonal dynamics of N accumulation in all the soil horizons. The seasonal course of nitrate accumulation did not correlate with the carbon dioxide production in the soils. In the soil under the highly productive birch stand from May 21 to October 2, 150 kg N ha-1 were mineralized, the nitrifi cation contribution being 19%. For this period, the mean daily ammonia emission from the forest soil equaled 58 ± 19 μg N m-2; the nitrogen loss was 95 g N ha-1.