We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Addition of nitrogen enhances stability of soil organic matter in a temperate forest.
- Authors
Chen, Z. J.; Geng, S. C.; Zhang, J. H.; Setälä, H.; Gu, Y.; Wang, F.; Zhang, X.; Wang, X. X.; Han, S. J.
- Abstract
Physicochemical protection of soil carbon provided by soil aggregates is critical to carbon ( C) sequestration in terrestrial ecosystems. However, the stability of soil organic matter ( SOM) in terrestrial ecosystems in response to atmospheric nitrogen ( N) deposition is unclear. In this study, N was added to a forest soil dominated by deciduous trees on Changbai Mountain, China, at three different rates (0, 25 and 50 kg N ha−1 year−1) from 2007 to 2012. Its effect on C content and stabilization was evaluated by soil fractionation and stable isotope ( δ 13C) analyses. The results showed that large macroaggregates (2-8 mm) decreased and small macroaggregates (0.25-2 mm) increased with increasing rates of N addition, whereas soil C content remained unchanged. Irrespective of the N treatments, the C content of soil organic matter ( SOM) fractions differed significantly between large and small macroaggregates, which suggests that the size of aggregate classes regulates C content in the SOM fractions. A slight increase in the C content of microaggregates within macroaggregates ( Mm) and that of silt and clay fractions was recorded with the addition of N at 50 kg N ha−1 year−1. This increase also occurred in the silt and clay fraction within microaggregates ( Intra- SC). Unprotected C (comprising the free light fraction ( Free- LF) and coarse particulate organic matter ( CPOM)) accounted for 18.9% only of the total C and decreased in response to the addition of N. The δ 13C signature and C/N ratios obtained for SOM fractions showed that newly formed C was transferred from POM to Intra- SC. Overall, our results suggested that long-term addition of N might promote stabilization of C by increasing small macro- and micro-aggregation within macroaggregates in temperate forest soil. Highlights Investigated stability of soil organic matter in response to long-term N addition in a deciduous forest., Physicochemical protection of soil organic matter by aggregates changed after N addition., Soil organic carbon in microaggregates within macroaggregates increased with N addition., Long-term N addition might promote C stabilization in temperate forest soil.
- Subjects
CARBON in soils; NITROGEN in soils; HUMUS; FOREST soils; SOIL structure
- Publication
European Journal of Soil Science, 2017, Vol 68, Issue 2, p189
- ISSN
1351-0754
- Publication type
Article
- DOI
10.1111/ejss.12404