不同区域稻田土壤复合体有机碳分配及δ^(13)C特征  

Distribution and δ^(13)C Characteristics of Organic Carbon in Soil Organo-mineral Complexes of Paddy Fields Located in Different Regions

作　　者：朱洁[1,2] 慈恩[1,2] 杨林章[3] 马力[3] 谢德体[1,2] 

机构地区：[1]西南大学资源环境学院,重庆400716 [2]重庆市三峡库区农业面源污染控制工程技术研究中心,重庆400716 [3]中国科学院南京土壤研究所,南京210008

出　　处：《水土保持学报》2011年第2期173-176,共4页Journal of Soil and Water Conservation

基　　金：中国博士后科学基金(20090460716201003306);重庆市自然科学基金资助项目(CSTC;2009BB1108);中央高校基本科研业务费专项资助项目(XDJK2009C060);重庆高校优秀成果转化资助项目;重庆市环境保护局环保科技项目(环科字2010第26号)

摘　　要：选取位于5个不同区域(吉林龙井、河南封丘、浙江慈溪、江西进贤和海南海口)的代表性稻田,对其土壤复合体有机碳分配及δ13C特征进行了研究。结果表明,不同区域稻田土壤中各粒级复合体含量(质量百分比)变化主要体现在<2μm和>50μm粒级部分。南方稻田0-20 cm土层中<2μm复合体含量较20-40 cm土层低,而北方稻田0-20 cm土层则较20-40 cm土层高。稻田0-20 cm和20-40 cm土层中,<50μm各粒级土壤复合体有机碳含量的变化趋势基本一致;>50μm复合体有机碳含量则在稻田20-40 cm土层中出现急剧下降,显著低于表层。农田土壤有机碳主要集中在<10μm复合体中。气候条件、耕作制度和起源土壤对农田土壤复合体有机碳分配有显著影响,其中稻田耕作环境更有利于表层粗有机体的累积。不同区域稻田0-20 cm土层中,土壤复合体粒级越小,其有机碳δ13C值越高,碳库活性越低;而20-40 cm稻田土层中复合体有机碳库活性则并非严格遵循粗粒活性高于细粒的规律,在>50μm粗粒复合体中表现尤为明显。Representative paddy fields were selected in five regions（Longjing of Jilin Province,Fengqiu of Henan province,Cixi of Zhejiang province,Jinxian of Jiangxi province and Haikou of Hainan province）.Distribution and δ13C characters of organo-mineral complexes in these paddy soils were studied.The results showed that the content（mass percent） changes of complexes 2 μm and 50 μm were more obvious than other particle-sizes complexes in paddy soils located in different regions.In southern paddy fields,the content of complex 2 μm in the 0-20 cm layer was lower than the 20-40 cm layer,and conversely in soil profiles of northern paddy fields.Distribution of organic carbon content in different particle-sizes complexes 50 μm kept consistent in the 0-20 cm layer and the 20-40 cm layer of paddy fields.Organic carbon content of complexes 50 μm in the 20-40 cm layer of paddy fields declined sharply,and was significantly lower than the topsoil.Soil organic carbon of cropland was mainly accumulated in complexes 10 μm.Climate conditions,cultivation system and original soil would have significant influence on distribution of organic carbon in soil organo-mineral complexes of cropland,and water culture was propitious to accumulation of coarse organism in the topsoil of paddy fields.In the 0-20 cm layer of paddy fields located in different regions,organic carbon with higher δ13C value and lower activity was contained in smaller particle-size complexes.The rule wasn＇t strictly followed in the 20-40 cm layer that the activity of organic carbon in coarse complex was higher than fine complex,and especially in coarse complex 50 μm.

关 键 词：稻田 有机无机复合体 有机碳 δ13C 剖面 

分 类 号：S153.62[农业科学—土壤学] P597.2[农业科学—农业基础科学]