生物质炭施用对水稻土有机质分子结构和组成的影响  

Effects of Biochar Application on Molecular Structure and Composition of Organic Matter in Paddy Soil

作　　者：宋凯悦 刘志伟[1,2] 刘伟 马睿凌 李世贤 卞荣军 郑聚锋[1,2] 潘根兴 SONG Kaiyue;LIU Zhiwei;LIU Wei;MA Ruiling;LI Shixian;BIAN Rongjun;ZHENG Jufeng;PAN Genxing(Institute of Resource,Ecosystem and Environment of Agriculture,Nanjing Agricultural University,Nanjing 210095,China;Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization,Nanjing 210095,China)

机构地区：[1]南京农业大学农业资源与生态环境研究所,江苏南京210095 [2]江苏省有机固体废弃物资源化协同创新中心,江苏南京210095

出　　处：《环境科学研究》2023年第10期1979-1987,共9页Research of Environmental Sciences

基　　金：国家自然科学基金项目(No.42277330,41877097);江苏省碳达峰碳中和科技创新专项资金项目(No.BE2022423)。

摘　　要：农田土壤施用生物质炭(BC)被认为是提高表层土壤固碳潜力的有效措施,但其对深层土壤有机质分子结构和组成特征的影响还认识不足.本文以BC施用4年后的水稻土为研究对象,基于傅里叶变换红外光谱(FTIR)和热裂解气质联用(Py-GC/MS)技术,探究BC施用对耕作层(A层,0~15 cm)、犁底层(Ap层,15~28 cm)和潴育层(W,28~50 cm)土壤有机碳(SOC)含量和有机质分子结构与组成的影响.结果表明:①与不施炭的对照(CK)处理相比,BC处理下A层SOC和可溶性有机碳(DOC)含量分别显著增加了13.0%和22.3%,Ap层DOC含量增加了20.8%,而W层SOC和DOC含量均无显著性变化.②从有机质化学结构来看,BC施用增加了各土层芳香族碳组分的相对峰强度,而降低了A层和Ap层多糖等碳水化合物的相对峰强度,有机质结构趋于芳香化.③BC施用明显增加了不同深度水稻土有机质分子的相对丰度并改变了分子组成.与CK处理相比,BC处理降低了各土层中氨基酸、氨基化合物、二元羧酸、羟基酸和糖类的相对丰度,特别是Ap层和W层;而BC处理则增加了各土层中烷烃类、胺类、杂环氮化合物、苯酚酯和多酚类的相对丰度.研究显示,施用BC增加了表层土壤中疏水性分子和芳香性化合物向深层土壤的迁移,增强了深层土壤碳库的稳定性.Biochar(BC)application has been regarded as an effective measure to increase soil carbon sequestration potential of topsoil,but its effect on the molecular structure and composition characteristics of deep soil organic matter has not been clearly understood.Paddy soil samples after 4 years of BC amendment were collected to investigate the effects of BC application on soil organic carbon content(SOC),molecular structure and composition of organic matter in the cultivation layer(A layer,0-15 cm),plowpan(Ap layer,15-28 cm)and hydrogric(W layer,28-50 cm)using Fourier transform infrared(FTIR)spectroscopy and pyrolysis gas chromatography-mass spectrometry(Py-GC/MS).The results showed that:(1)Compared with non-biochar amended soil,the contents of SOC and dissolved organic carbon(DOC)in layer A significantly increased by 13.0%and 22.3%,respectively,and the content of DOC in layer Ap increased by 20.8%,while the contents of SOC and DOC in layer W had no significant change in the BC treatment.(2)As far as the chemical structure of organic matter fractions were concerned,BC application increased the relative absorption peak intensities of aromatic carbon fractions in each soil layer,while decreasing the relative absorption peak intensities of carbohydrates such as polysaccharides in the A and Ap layers,and the organic matter structure tended to be aromatic.(3)BC application significantly increased the relative molecular abundance and changed the molecular composition of organic matter in paddy soils at different depths.Compared with the CK treatment,the relative abundance of amino acids,amino compounds,dicarboxylic acids,hydroxyl acids and sugars in BC treatment decreased in each soil layer,especially in the Ap and W layers.However,the relative abundance of alkanes,amines,heterocyclic nitrogen compounds,phenol esters and polyphenols in the BC treatment increased significantly in soil layers A,Ap and W.This study indicates that BC application increases the migration of hydrophobic molecules and aromatic compounds from the su

关 键 词：生物质炭 水稻土 土壤有机质分子组成 深层土壤 固碳 

分 类 号：X53[环境科学与工程—环境工程] S153.6[农业科学—土壤学]