红壤丘陵区不同地类活性有机碳分布特征及与草本生物量关系

以南方红壤丘陵区荒地、松林、草地坡地小区为研究对象,在研究了土地利用方式对土壤活性有机碳和草本生物量分布特征影响规律的基础上,深入探讨了不同土地利用方式下土壤活性有机碳与草本生物量的定量关系.结果表明不同土地利用方式对土壤易氧化有机碳(ROC)、水溶性有机碳(DOC)、微生物量碳(MBC)以及草本生物量的分布特征均有重要影响,其中草地坡面小区的活性有机碳各组分和草本生物量均高于荒地和松林小区;定量关系研究表明,影响荒地、松林和草地草本生物量的活性有机碳组分分别为DOC,ROC,DOC和MBC,其中荒地坡面DOC主要通过土壤有机碳(SOC)对草本生物量产生影响.

Effect of Land Use Type on the Distribution of Labile Organic Carbon and Its Relationship to Herb Biomass in Red Soil Hilly Region

The different land use plots (i.e., wasteland, pinewood land and grassland in this study) of red soil hilly region were selected as the research regions.On the basis of detecting the effects of land use type on the distribution properties of soil labile organic carbon and herb biomass, this research investigated the quantitative relation between soil labile organic carbon and herb biomass under the different land use types.The results showed that land use types had significant effects on the distribution of soil readily oxidized organic carbon(ROC), dissolved organic carbon (DOC), microbial biomass carbon (MBC) and herb biomass at plot scale, and all labile organic carbon components and herb biomass of grassland plot were higher than those of wasteland and pinewood land plots.Quantitative analysis showed that the soil labile organic carbon components, which had statistically affected the herb biomass of the three plots, were DOC (wasteland plot), ROC (pinewood plot), DOC and MBC (grassland plot).In addition, the influence of DOC on herb biomass in wasteland plot was generally through SOC.