PJB-2017-604
Soil labile and recalcitrant organic carbon under different forest types in China
Zhao Juan
Abstract
The influence of forest type on soil organic carbon (C) quantity and quality was studied in Pinus koraiensis–Quercus mongolica mixed forest, Larix olgensis forest and P. tabulaeformis forest in Northeast China and in Phyllostachys pubescens, P. massoniana and Castanopsis fargesii forests in Southeast China. To obtain a thorough understanding of the interaction between forest type and soil C fraction, we used a path analysis to determine the responses of labile and recalcitrant organic C to forest type. The results showed that there were substantial differences in the size and distribution of C content and fractions. Soil total organic C (TOC) ranged from 27.72 to 145.78 g kg-1 at the depth of 0–10 cm and was the lowest in the P. massoniana forest and the highest in the mixed P. koraiensis–Q. mongolica forest. Microbial biomass carbon (MBC) ranged from 0.28 g kg-1 in P. massoniana to 1.52 g kg-1 in mixed P. koraiensis–Q. mongolica, whereas the recalcitrant organic carbon (ROC) ranged from 7.47 to 55.01 g kg-1. MBC/TOC was lower whereas ROC/TOC was higher in Northeast than in Southeast China. The path analysis indicated that ROC had the highest direct effect on the TOC, followed by MBC. Therefore, ROC and MBC can be used as selection criteria for the responses of soil C fractions to forest type. Moreover, the response of ROC to forest type will determine the magnitude of the feedback to global climate change due to substantial storage of ROC in soils.
To Cite this article:
Download
