棕色石灰土和红壤碳释放对添加矿物质(Fe(OH)_3和CaCO_3)的响应  

Carbon release from brown limestone and red soils in response to addition of Fe(OH)_3 and CaCO_3

作　　者：肖谋良[1,2] 陈香碧[1,3] 李杨[1,3] 何寻阳[1,3] 申燕 苏以荣[1,3] 

机构地区：[1]中国科学院亚热带农业生态研究所,亚热带农业生态过程重点实验室,长沙410125 [2]广西师范大学生命科学学院,广西桂林541004 [3]中国科学院环江喀斯特农业生态试验站,广西环江547100 [4]贵州省烟草公司毕节市公司,贵州毕节551700

出　　处：《生态学杂志》2014年第11期2936-2942,共7页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(41301273;41171246);国家科技支撑计划项目(2012BAD05B03-6);中国科学院西部之光人才培养计划"西部博士资助项目";贵州省烟草公司毕节市公司科技项目(BJYC-201301)资助

摘　　要：为阐明喀斯特地区土壤演变过程（脱钙镁富铁铝化作用）中土壤特有矿物对碳释放的影响,本文以喀斯特区典型的高和低有机碳含量水平的棕色石灰土和红壤为研究对象,通过80 d室内培养试验,研究土壤碳释放（有机碳和无机碳）对添加土壤中特有矿物质（Ca14CO3和Fe（OH）3）的响应。结果表明：添加Ca14CO3和Fe（OH）3均对棕色石灰土和红壤中原有碳的释放有正激发效应,以前者（培养结束时土壤原有碳累积释放量为823.8～1367.2 mg·kg-1）显著大于后者（502.5～635.7 mg·kg-1）,说明喀斯特地区土壤由富钙镁的石灰土向富铁铝的红壤演变过程可能是土壤碳库逐渐稳定的过程。添加Ca14CO3和Fe（OH）3后,土壤原有碳的累积释放量的大小与土壤有机碳本身含量水平密切相关,均以高量有机碳红壤〉低量有机碳红壤和石灰土〉高量有机碳石灰土（P〈0.05）。培养过程中,无论是添加Ca14CO3还是Fe（OH）3,土壤可溶性有机碳（DOC）含量与碳释放激发效应的变化趋势一致,表明DOC可用于指示棕色石灰土和红壤激发效应强弱。土壤微生物生物量碳与碳释放激发效应的变化趋势不一致,说明添加Ca14CO3或Fe（OH）3对土壤原有碳的激发效应主要源于外源物添加后改变了土壤物理和化学环境,而土壤微生物的贡献相对较少。To clarify the effects of minerals on soil organic carbon mineralization in soil evolution, typical brown limestone soil and red soil with both high and low organic carbon contents were collected from a subtropical karst region. An 80-day incubation experiment （25 ℃ ） by adding either Ca14CO3 or Fe（OH）3 to the test soils was conducted to study the release process of original organic and inorganic carbon. Results showed that the addition of either Ca14 CO3 or Fe （OH） 3 promoted the carbon release. At the end of the incubation, the accumulatively released amounts of the original carbon （organic and inorganic carbon） were 823.8-1367.2 mg·kg-1 and 502.5-635.7 mg·kg-1 after the additions of Ca14CO3 and Fe（OH）3, respectively. This result indicates that the soil evolution from brown limestone soil to red soil in karst region may increase the stability of carbon stock. After adding Cal4CO3 and Fe（ OH）3, the priming effect on soil carbon was strongly related to the original soil carbon content, and this correlation was in the

关 键 词：红壤 棕色石灰土 碳释放 碳酸钙 氢氧化铁 

分 类 号：S153.6[农业科学—土壤学]