农业环境科学学报2012，Vol.31Issue(10)：1956-1964,9.
喀斯特高原典型小流域土壤有机碳及其组分的分布特征
Characteristics of the Distributions of Soil Organic Carbon and Main Components in a Typical Catchment in the Karst Plateau
摘要
Abstract
Understanding the distributions of soil organic carbon(SOC) and its main fractions in a typical Karst catchment is a fundamental issue for restoring and reconstructing the degraded Karst ecosystems in Southwest China. 248 regular grid designed soil samples were collected at the Wangjiazhai Village of Qingzhen County in Guizhou Province( a typical Karst plateau) in Jan. 2010, and their SOC, dissolved organic carbon( DOC), and microbial biomass carbon( MBC) were determined. The results showed that the contents of SOC, DOC and MBC in the topsoils(0～20 cm) of shrub land were 56.86 g·kg-1, 68.74 mg·kg-1 and 264.12 mg·kg-1, respectively and they were significantly higher than those in the topsoils of upland and paddy field (P<0.05 ). The ratios of SOC/MBC ranged from 0.45% to 0.55% in the topsoils under different land use types. SOC and its main fractions were significantly influenced by the land use types. Covariance analysis showed that MBC was apparently influenced by land use type and pH, while SOC and DOC were influenced by geographic latitude. No significant correlation was found between SOC and MBC, but the correlations between DOC and MBC were variable under different land use types. The MBC contents were significantly decreased with the increase of soil depths within 0～30 cm for shrub land(P<0.05). The contents of DOC for paddy field in the 20～30 cm soil were significantly lower than those in the 0～20 cm soil(P<0.05). The SOC density in the very topsoils(0～ 10 cm) in shrub land was higher than those in other land use types, but in the 1 m soil profile, the SOC densities in upland(155.97 tˉhm-2) and paddy(107.92 t·hm-2) were significantly higher than that in shrub land (76.14 t · hm-2) (P<0.05 ). Therefore, the upland and paddy field seem favor for the SOC accumulation in soils, compared with ihe shrub land. However, in a comprehensive manner, the protection of shrub land and the deployment of straw return practice in the agricultural fields are eventually helpiul for the SOC accumulation, the restoration of the regional ecological environment and the regional sustainable development.关键词
喀斯特高原区/土壤有机碳/微生物生物量碳/可溶性有机碳/分布特征Key words
Karst plateau/ soil organic carbon/ microbial biomass carbon/ dissolved organic carbon/ distribution分类
资源环境引用本文复制引用
邱虎森,苏以荣,陈香碧,黎蕾,李杨,何寻阳..喀斯特高原典型小流域土壤有机碳及其组分的分布特征[J].农业环境科学学报,2012,31(10):1956-1964,9.基金项目
中国科学院知识创新重要方向项目(KSCX2-YW-436) （KSCX2-YW-436）
中国科学院战略性先导科技专项(XDA05070403) （XDA05070403）
中国科学院西部行动计划项目(KZCX2-XB3-10) （KZCX2-XB3-10）
国家基金项目(41171246) （41171246）
