Net nitrogen mineralization and nitrification rates in forest soil in northeastern Taiwan
Article first published online: 1 MAR 2010
© 2010 Japanese Society of Soil Science and Plant Nutrition
Soil Science & Plant Nutrition
Volume 56, Issue 1, pages 177–185, February 2010
How to Cite
OWEN, J. S., KING, H. B., WANG, M. K. and SUN, H. L. (2010), Net nitrogen mineralization and nitrification rates in forest soil in northeastern Taiwan. Soil Science & Plant Nutrition, 56: 177–185. doi: 10.1111/j.1747-0765.2009.00427.x
- Issue published online: 1 MAR 2010
- Article first published online: 1 MAR 2010
- Received 15 April 2009. Accepted for publication 8 November 2009.
- forest soil;
We used a laboratory incubation approach to measure rates of net N mineralization and nitrification in forest soils from Fu-shan Experimental Forest WS1 in northern Taiwan. Net mineralization rates in the O horizon ranged from 4.0 to 13.8 mg N kg−1 day−1, and net nitrification rates ranged from 2.2 to 11.6 mg N kg−1 day−1. For mineral (10–20 cm depth) soil, net mineralization ranged from 0.06 to 2.8 mg N kg−1 day−1 and net nitrification rates ranged from 0.02 to 2.8 mg N kg−1 day−1. We did not find any consistent differences in N mineralization or nitrification rates in soils from the upper and lower part of the watershed. We compared the rates of these processes in three soil horizons (to a soil depth of 30 cm) on a single sampling date and found a large decrease in both net N mineralization and nitrification with depth. We estimated that the soil total N pool was 6,909 kg N ha−1. The present study demonstrates the importance of the stock of mineral soil N in WS1, mostly organic N, which can be transformed to inorganic N and potentially exported to surface and ground water from this watershed. Additional studies quantifying the rates of soil N cycling, particularly multi-site comparisons within Taiwan and the East Asia–Pacific region, will greatly improve our understanding of regional patterns in nitrogen cycling.