Welcome to Acta Prataculturae Sinica ! Today is Share:

Acta Prataculturae Sinica ›› 2015, Vol. 24 ›› Issue (5): 53-65.DOI: 10.11686/cyxb20150507

Previous Articles     Next Articles

Effect of Citrus tree/Stropharia mushrooms intercropping on “purple soil” labile organic carbon in the Three Gorges Reservoir region

ZHANG Yang, LIU Yue-Jiao, NI Jiu-Pai*, XIE De-Ti   

  1. College of Resources and Environment, Southwest University, Chongqing 400716, China
  • Received:2014-11-26 Online:2015-05-20 Published:2015-05-20

Abstract: In order to provide basic data and a theoretical basis for soil carbon cycle and climate change mitigation research, the effect of Citrus tree/Stropharia mushrooms intercropping on “purple soil” labile organic carbon was analyzed. Five tillage practices: high density intercropping (HD), traditional cultivation (TC), sparse intercropping (SP), bare ground tillage (BT) and straw mulching tillage (ST) were examined to analyze the soil total organic carbon (TOC), dissolved organic carbon (DOC), rapidly oxidized organic carbon (ROC), light fraction organic carbon (LFOC) and soil microbial biomass carbon (SMBC) in citrus groves. During the growing season of Stropharia mushrooms, the density of Citrus tree/Stropharia mushrooms intercropping significantly affected the labile carbon (including DOC, ROC, LFOC, SMBC). As expected, the content of total organic carbon and labile carbon in the upper layer (0-10 cm soil depth) was significantly higher than in the lower layer (30-50 cm soil depth). The content of labile carbon (including DOC, ROC, LFOC, SMBC) in the upper soil layer under high density intercropping (HD) practice was significantly higher than under the other treatments (P<0.05), while the contents of dissolved organic carbon (DOC), light fraction organic carbon (LFOC) and soil microbial biomass carbon (SMBC) in lower soil layer under sparse intercropping (SP) were higher than under the other treatments. Intercropping density was significantly negatively correlated with total organic carbon (TOC) and rapidly oxidized organic carbon (ROC). There was a significant negative correlation between the intercropping density and dissolved organic carbon (DOC), light fraction organic carbon (LFOC) and soil microbial biomass carbon (SMBC). In addition, there was a significant positive correlation among different fractions of labile carbon. Citrus tree/Stropharia mushrooms intercropping enhanced the soil carbon pool management index in the upper soil layer, but decreased the same index in the lower soil layer. Citrus tree/Stropharia mushrooms intercropping enhanced formation and accumulation of soil labile carbon and increased soil carbon storage in this soil type in the Three Gorges Reservoir region.