Back to Search
Start Over
N isotopes and N cycle in the TieShanPing subtropical forest ecosystem, Southwestern China.
- Source :
- Environmental Monitoring & Assessment; Jul2009, Vol. 154 Issue 1-4, p301-308, 8p, 4 Charts, 1 Graph
- Publication Year :
- 2009
-
Abstract
- Nitrogen is essential for forest growth and forest stand development. It is commonly a limited factor for forest productivity. We examined δ<superscript>15</superscript>N values in soils and plants by studying the sources of N used by vegetation and cycles of N in a 43-year-old plantation of the TieShanPing forest ecosystem in southwestern China, dominated by massone pine ( Pinus massoniana). The N concentration of plant materials ranges from 1.1% to 2.2%. The nitrogen concentration of P. massoniana was 1.3% while soils showed the concentration of 0.04–0.15%. Regarding natural abundance of <superscript>15</superscript>N, large significant variation (−6.0‰ to −3.8‰) in δ<superscript>15</superscript>N values was observed among shrub and tree leaves. δ<superscript>15</superscript>N values were also significantly varied from −4.7‰ to −3.8‰ among the pioneer species in the plantation. Soil δ<superscript>15</superscript>N values (3.1–6.3‰) were significantly enriched compared to those values in plant samples. Despite the negative δ<superscript>15</superscript>N values of the vegetation cover, the high δ<superscript>15</superscript>N values in the topsoil indicate that return of N to soils by litter-fall is minimal on TieShanPing and the present forests do not change very much the soil <superscript>15</superscript>N signals at the surface layer. The positive δ<superscript>15</superscript>N values may also indicate large N losses from the soil system vial leaching, volatilization and plant uptake. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 01676369
- Volume :
- 154
- Issue :
- 1-4
- Database :
- Complementary Index
- Journal :
- Environmental Monitoring & Assessment
- Publication Type :
- Academic Journal
- Accession number :
- 42993003
- Full Text :
- https://doi.org/10.1007/s10661-008-0398-z