紫色丘陵区不同土地利用方式下土壤活性有机碳垂直分布特征  

Vertical Distribution of Labile Soil Organic Carbon on Different Land Use in Purple Hill Area

作　　者：何鹏[1,2] 邓良基[1,2] 苟曦[1,2] 任秋容[1,2] 

机构地区：[1]四川农业大学资源环境学院 [2]四川省土地信息重点实验室,四川雅安625014

出　　处：《山地学报》2006年第B10期21-26,共6页Mountain Research

基　　金：四川省教育厅自然科学重点项目资助（2003A009）.

摘　　要：用KMnO4氧化法测定了紫色丘陵区疏林地、荒草地和坡耕地三种土地利用方式下土壤活性有机碳含量和分配比例，分析了土壤活性有机碳在土壤剖面垂直方向上的分布特征。结果表明：不同土地利用方式下各坡位土壤剖面有机碳含量均是在0—5cm层富集，之后随着深度的增加逐渐降低；土壤活性有机碳含量总体上随土层加深而递减，其中疏林地土壤活性有机碳含量最高，为2．01±0．49—0．36±0．07gC／kg，荒草地土壤活性有机碳含量较少，为1．54±0．44—0．16±0．04gC／kg，坡耕地活性有机碳含量最低，为1．29±0．28—0．17±0．01gC／kg，不同土地利用方式下活性有机碳的含量为疏林地〉荒草地〉坡耕地；不同土地利用方式土壤活性有机碳分配比例为13．29±0．70％-5．25±0．23％，其中疏林地为12．43±0．43％-7．88±1．85％，荒草地为13．29±0．70％-5．37±0．58％，坡耕地为11．34±0．44％-5．25±0．23％，不同土地利用方式之间土壤活性有机碳分配比例差异较小。相关性分析显示，疏林地、荒草地和坡耕地土壤有机碳、全氮和活性有机碳含量之间有极显著的相关性。Soil carbon is a large component of the global carbon cycle, Soil labile organic carbon （SLOC） is the fraction of soil organic matter that is most sensitive to changes in land-use. The LOC concentrations were determined using a KMnO4（333 mmol/L） oxidation technique. The results showed that the content of SOC ondifferent land use was concentrated in 0 -5 cm profile;the content of LOC ranged from 2.01 ±0.49 g C/kg to 0.16 ±0.04 g C/kg. The content of LOC on different land use withdepth was increase, the content of LOC in open woodland was the highest between 2.01 ± 0.49 g C/kg and 0.36 ± 0.07 g C/kg, the content of LOC in grassland was between 1.54 ± 0.44 g C/kg and 0.16 ± 0.04 g C/kg, the content of LOC in slope cultivated lands between 1.29 ± 0.28 g C/kg and 0.17 ±0.01 g C/kg, The mean content of LOC on different land use was open woodland 〉 grass- land 〉 cultivated lands. The LOC fraction was between 13.29 ±0.70% and 5.25±0.23% in open woodland, the LOC fraction was between 13.29 ±0.70% and 5.37 ±0.58% in grassland, the LOC fraction was between 11.34 ± 0.44% - 5.25 ± 0.23% in slope cultivated lands, the differences of LOC fraction among the different land use were lower. The correlation coefficient of SOC, STN and LOC were significant correlation among the different land use.

关 键 词：活性有机碳 土壤有机碳 土地利用 垂直分布 紫色土 

分 类 号：S159.2[农业科学—土壤学]