摘要
以江汉平原四湖地区的果园、旱地、水田和水旱轮作等土壤为研究对象,通过分析其总有机碳与活性有机碳含量、腐殖质与轻重组组成特点,以期阐明不同土地利用方式对农田土壤有机碳组成的影响。结果表明:不同利用方式下表层土壤有机碳含量差异较大,其中以水田最高、果园最小,随着土壤剖面深度的增加,有机碳含量逐步降低;腐殖质占总有机碳比例较高,其中果园和旱地大于0.91,水旱轮作略低,而水田仅为0.78;不同利用方式下,各形态的腐殖质碳含量存在差异,活性较高的富里酸在水田和水旱轮作土壤中含量相对较高;稳定性有机碳占总有机碳的百分比大小顺序为:水旱轮作≈旱地>果园>水田,轻组组分在各利用方式下表现为:水田>旱地>果园>水旱轮作,而水旱轮作下重组碳容量占总有机碳的百分比最高。这表明水旱轮作既有利于土壤有机碳的积累,又利于土壤有机碳稳定性的增加。上述结果可为该区土壤管理措施的制订提供科学参考。
The soil samples in orchard,dryland,paddy,and the field with dryland and paddy rotation were collected from Houhu state farm of Qianjiang City,Hubei Province,where is the centre of Jianghan plain.The total and active organic carbon,composition of humus,and light and heavy fractions were measured.The contents of organic carbon（OC） in topsoil were different under land use changes.The OC content for paddy soil was the highest and that for orchard soil was the lowest.The ratios of OC in humus to total SOC for orchard,dryland,paddy,and rotation soil were 0.98,0.91,0.78 and 0.86,respectively.The contents of OC in fulvic acid for paddy and rotation soils were higher than those in other soils.The proportion of stable organic carbon in total SOC was in the order of rotation≈drylandorchardpaddy,and the light fraction followed the sequence of paddydrylandorchardrotation.It was suggested that the SOC content would be increased under water culture.However,the SOC stability decreased under water culture,and it would lost easily when the environment changed.Rotation soil should be paid attention,which was both high in total and stable OC content.It indicates that rotation culture will not only increase SOC content,but also increase SOC stability.These results will be helpful to provide scientific references to develop rational ways of soil management and cultivation.
出处
《水土保持研究》
CSCD
北大核心
2012年第6期24-28,共5页
Research of Soil and Water Conservation
基金
国家自然科学基金项目(40971144,41201231)
