Effects of long-term litter removal on soil organic carbon and multiple components in subtropical Cunninghamia lanceolata forest
Aims Leaf litter and root input are two major resource of soil organic carbon(SOC)accumulation.Quantifying the effects of leaf litter and root removal on SOC pool and its multiple components has implication for understanding the mechanisms of SOC stabilization in forest ecosystem.Methods Based on a long-term(12 years)litter removal experiment including control(CK),leaf litter removal(NL),root removal(NR),and both leaf litter and root removal(NLR)that conducted in Hunan Huitong Forest Ecosystem National Field Scientific Observation and Research Station,Chinese Academy of Sciences,we compared the relative importance of leaf litter and root removal on multiple components of SOC pool in a subtropical Cunninghamia lanceolata plantation in different season.Important findings Although leaf litter and root removal both reduced SOC content,the relative contribution of leaf litter and root removal on multiple SOC components were different.Specifically,the NL reduced more SOC,soil mineral-associated organic carbon(MAOC),heavy fraction organic carbon(HFOC)and readily oxidizable carbon(ROC)contents than NR and NLR.While,the NR decreased more soil particulate organic carbon(POC)content than NL and NR.In contrast,the NLR had more negative effect on light fraction organic carbon(LFOC)content than other two treatments.Correlation analysis and redundancy analysis showed that SOC components contents were positively correlated with soil total nitrogen content and carbon to nitrogen ratio.Besides,seasonal variability had significant effects on POC,LFOC contents,and their contribution of multiple carbon components to SOC.Moreover,the correlation between SOC component contents and total phosphorus content and carbon to phosphorus ratio was enhanced in winter compared with summer.Taken together,our study provides new evidence for the long-term effects of long-term litter removal on SOC and its multiple components in Chinese fir plantation,which has implications for predicting the response and feedback of SOC accumulation to global changes.
leaf litter removalroot removalsoil organic carboncarbon componentseasonal variabilityChinese fir plantation
万方数据
维普
