title: Factors controlling accumulation of soil organic carbon along vegetation succession in a typical karst region in Southwest China.
abstract: Vegetation succession enhances the accumulation of carbon in the soil. However, little is known about the mechanisms underlying soil organic carbon (SOC) accumulation in different vegetation types in the karst region of Southwest China. The goal of this study was to identify and prioritize the effects of environmental parameters, including soil physico-chemical properties, microbial biomass, enzyme activities, and litter characteristics, on SOC accumulation along a vegetation succession sere (grassland, shrubland, secondary forest, and primary forest) in the karst landscape of Southwest China. Relationships between these parameters and SOC were evaluated by redundancy analysis. The results showed that SOC accumulation was significantly different among vegetation types (P<0.01) and increased with vegetation succession (from 29.10g·kg(-1) in grassland to 73.92g·kg(-1) in primary forest). Soil biochemistry and physical characteristics significantly affected the accumulation of SOC. Soil microbial biomass showed a predominant effect on SOC in each of the four vegetation types. In addition, the soil physical property (especially the silt content) was another controlling factor in the early stages (grassland), and urease activity and saccharase activity were important controlling factors in the early-middle and middle-late stages, respectively. Litter characteristics only showed mild effects on SOC accumulation. Variation partitioning analysis showed that the contribution of sole main factors to SOC variation decreased, while the interaction effect among parameters increased along the succession gradient.
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China; Huanjiang Observation and Research Station of Karst Ecosystem, Chinese Academy of Sciences, Huanjiang, Guangxi Zhuang Autonomous Region 547100, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Shujuan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China; Huanjiang Observation and Research Station of Karst Ecosystem, Chinese Academy of Sciences, Huanjiang, Guangxi Zhuang Autonomous Region 547100, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China; Huanjiang Observation and Research Station of Karst Ecosystem, Chinese Academy of Sciences, Huanjiang, Guangxi Zhuang Autonomous Region 547100, China. Electronic address: kelin@isa.ac.cn.
authors.forename: Kelin
authors.initials: K
authors.lastname: Wang
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China; Huanjiang Observation and Research Station of Karst Ecosystem, Chinese Academy of Sciences, Huanjiang, Guangxi Zhuang Autonomous Region 547100, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Fujing
authors.initials: F
authors.lastname: Pan
authors.affiliation: Changsha university, Changsha 410003, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Yang
authors.affiliation: Changjiang Project Supervision & Consultancy Co. Ltd, Wuhan 430010, China; Changjiang Ecology (Hubei) Technology Development LLC, Wuhan 430010, China.
authors.forename: Shiyan
authors.initials: S
authors.lastname: Shu
mesh_terms: D018533:Biomass; D002244:Carbon / Q000032:analysis*; D057486:Carbon Cycle; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D065928:Forests; D012987:Soil / Q000737:chemistry*
chemical_list: D012987:Soil; D002244:Carbon
keywords: Enzyme activities; Karst peak-cluster depression; Litter; Microbial biomass; Silt content; Soil organic carbon