Premium
Litter type control on soil C and N stabilization dynamics in a temperate forest
Author(s) -
Hatton PierreJoseph,
Castanha Cristina,
Torn Margaret S.,
Bird Jeffrey A.
Publication year - 2015
Publication title -
global change biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.146
H-Index - 255
eISSN - 1365-2486
pISSN - 1354-1013
DOI - 10.1111/gcb.12786
Subject(s) - temperate forest , litter , temperate climate , temperate rainforest , soil organic matter , organic matter , plant litter , chemistry , cycling , biogeochemical cycle , soil horizon , nutrient , environmental science , soil water , agronomy , environmental chemistry , botany , ecology , ecosystem , soil science , biology , forestry , geography
While plant litters are the main source of soil organic matter ( SOM ) in forests, the controllers and pathways to stable SOM formation remain unclear. Here, we address how litter type ( 13 C/ 15 N‐labeled needles vs. fine roots) and placement‐depth (O vs. A horizon) affect in situ C and N dynamics in a temperate forest soil after 5 years. Litter type rather than placement‐depth controlled soil C and N retention after 5 years in situ , with belowground fine root inputs greatly enhancing soil C (x1.4) and N (x1.2) retention compared with aboveground needles. While the proportions of added needle and fine root‐derived C and N recovered into stable SOM fractions were similar, they followed different transformation pathways into stable SOM fractions: fine root transfer was slower than for needles, but proportionally more of the remaining needle‐derived C and N was transferred into stable SOM fractions. The stoichiometry of litter‐derived C vs. N within individual SOM fractions revealed the presence at least two pools of different turnover times (per SOM fraction) and emphasized the role of N‐rich compounds for long‐term persistence. Finally, a regression approach suggested that models may underestimate soil C retention from litter with fast decomposition rates.