Soil organic carbon stratification ratio as an indicator of carbon sequestration and soil quality in ecological restoration
Stratification ratio of soil organic carbon (SOC) pools with soil depth is widely recognized as a valid indicator of soil quality and soil ecosystem functioning in farmland. The purpose of this study was to assess the feasibility of using SOC stratification ratio (SR) as an index to estimate the dynamics of SOC sequestration and soil quality during ecological restoration. Typical rehabilitation types in the hilly Loess Plateau including three re-vegetation types with different stand ages and slope transects and three kinds of agriculture managements were selected. The result showed that SOC density (SOCD) and SR had a consistent significant linear growth trend along re-vegetation chronosequence, and annual increase rates of SR (0-5:5-10cm) and SR (0-5:20-30cm) to that of SOCD were about 1:5 and 1:15, which meant that SR of shallow soil layer (0-10cm) could estimate SOC accumulation of 0-30cm depth. Soil quality parameters (i.e., soil organic matter (SOM), total N (TN) and available N) improved significantly during rehabilitation and had the same variation as SR with re-vegetation years. SR also indicated the differences of SOC sequestration and soil quality (i.e., SOM, TN and available N) among different re-vegetation types. SOCD and SR had a similar spatial distribution under different landforms except the case influenced by un-uniform effects of landform and microclimate. But SR could not precisely indicate the variation of SOC sequestration and soil quality of different agricultural managements in our study, because all these managements contented soil disturbance or surface organic matter loss. SR (0-5:5-10cm, 0-5:20-30cm) strongly correlated with SOCD of all sites in this study (R2=0.5214, 0.7915), as well as main soil quality parameters (i.e., SOM, TN and available N). The results showed that SR was an efficient indicator of SOC sequestration and soil quality, and SR (0-5:20-30cm)＞2 could indicate a distinct improvement of SOC sequestration and soil quality as ecosystem rehabilitated in the hilly Loess Plateau.
Soil organic carbon (SOC) SOC stratification ratio (SR) soil quality ecological restoration re-vegetation hilly Loess Plateau
Zheng Wang Guo-Bin Liu Ming-Xiang Xu
College of Forestry, Northwest A&F University, Yangling, 712100, China College of Forestry, Northwest A&F University, Yangling, 712100, China;State Key Laboratory of Soil
国际会议
西安
英文
973-978
2010-10-11（万方平台首次上网日期，不代表论文的发表时间）