title: Soil carbon and nitrogen stocks in forests along an altitudinal gradient in the eastern Himalayas and a meta-analysis of global data.
abstract: High-altitude soils potentially store a large pool of carbon (C) and nitrogen (N). The assessment of total C and N stocks in soils is vital to understanding the C and N dynamics in terrestrial ecosystems. In this study, we examined effects of altitude and forest composition on soil C and N along a transect from 317 to 3300 m a.s.l. in the eastern Himalayas. We used meta-analysis to establish the context for our results on the effects of altitude on soil C, including variation with depth. Total C and N contents of soils significantly increased with altitude, but decreased with soil depth. Carbon and N were similarly correlated with altitude and temperature, and temperature was seemingly the main driver of soil C along the altitudinal gradient. Altitude accounted for 73% of the variation in C and 47% of the variation in N stocks. Soil pH and cation exchange capacity were correlated with both soil C and N stocks. Increases in soil C and N stocks were related to forest composition, forest basal area as well as quantity of leaf litter that were in turn influenced by altitude and temperature. Concentrations of C in foliage increased by 2.1% for every 1000 m rise in altitude, while that in leaf litter increased by 2.3%.
authors: Centre for Carbon, Water and Food, Faculty of Agriculture and Environment, The University of Sydney, Eveleigh, NSW, 2015, Australia.
authors: Sonam
authors: S
authors: Tashi
authors: Centre for Carbon, Water and Food, Faculty of Agriculture and Environment, The University of Sydney, Eveleigh, NSW, 2015, Australia.
authors: Balwant
authors: B
authors: Singh
authors: Centre for Carbon, Water and Food, Faculty of Agriculture and Environment, The University of Sydney, Eveleigh, NSW, 2015, Australia.
authors: Claudia
authors: C
authors: Keitel
authors: Centre for Carbon, Water and Food, Faculty of Agriculture and Environment, The University of Sydney, Eveleigh, NSW, 2015, Australia.
authors: Mark
authors: M
authors: Adams
mesh_terms: D000531:Altitude; D001631:Bhutan; D018533:Biomass; D002244:Carbon / Q000032:analysis*; D065928:Forests; D009584:Nitrogen / Q000032:analysis*; D012987:Soil / Q000737:chemistry*
chemical_list: D012987:Soil; D002244:Carbon; D009584:Nitrogen
keywords: Himalayas; altitude; carbon stocks; forest; meta-analysis; nitrogen stocks