黑土根际土壤有机碳及结构对长期施肥的响应  

Changes of soil organic carbon and its structure in rhizosphere of black soil under long-term fertilization

作　　者：陈磊[1,2] 郝小雨[1] 马星竹[1] 周宝库[1] 王爽[1] 魏丹[3] 周磊 刘荣乐[5] 汪洪 Chen Lei;Hao Xiaoyu;Ma Xingzhu;Zhou Baoku;Wang Shuang;Wei Dan;Zhou Lei;Liu Rongle;Wang Hong(Institute of Soil and Fertilizer and Environment Resources,Heilongjiang Academy of Agricultural Sciences,Harbin 150086,China;Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Qualityof Arable Land/Key Laboratory of Plant Nutrition and Fertilizer,Ministry of Agriculture and Affairs,Beijing 100081,China;Institute of Plant Nutrition and Resources,Beijing Academy of Agriculture and Forest,Beijing 100097,China;Heilongjiang Academy of Sciences,Harbin 150001,China;Agro-Environmental Protection Institute of Ministry of Agriculture and Rural Affairs,Tianjin 300191,China)

机构地区：[1]黑龙江省农业科学院土壤肥料与资源环境研究所,哈尔滨150086 [2]中国农业科学院农业资源与农业区划研究所/耕地培育技术国家工程实验室/农业农村部植物营养与肥料重点实验室,北京100081 [3]北京农林科学院植物营养与资源研究所,北京100097 [4]黑龙江省科学院,哈尔滨150001 [5]农业农村部环境保护科研监测所,天津300191

出　　处：《农业工程学报》2022年第8期72-78,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：科技部科技基础资源调查专项(2021FY100406);黑龙江省博士后资助项目(LBH-Z20093)。

摘　　要：由于人类农业措施的干扰,氮肥和畜禽粪污大量输入到黑土中,对土壤有机碳库产生了较大负面影响。根际有机碳在调控土壤碳循环和养分转化中发挥着重要的作用。探明根际有机碳对不同养分的生态响应,可为不同施肥处理下黑土农田生态系统碳固持和农田可持续利用提供理论依据。该研究以黑土长期定位试验为基础,采集长期不施肥(CK)、常量氮(N)、二倍量氮(N2)、常量有机肥(M)、二倍量有机肥(M2)、常量有机肥+常量氮(MN)、二倍量有机肥+二倍量氮(M2N2)7个处理下大豆根际土壤,分析了根际有机碳和活性有机碳特征,同时利用固态核磁共振技术分析其光谱特征。结果表明,N、M2、MN和M2N2处理的根际土壤有机碳含量显著高于非根际水平,且以MN和M2N2处理的根际效应最显著,分别比非根际增加了18.3%和26.7%。分析核磁共振光谱显示,与非根际土壤相比,根际土壤具有较高的烷氧基碳比例和较低芳香碳比例,表明根际效应能够改变土壤有机碳结构比例。与不施肥处理相比,大部分施肥处理提升了黑土根际有机碳含量,其中以氮肥马粪配施和二倍量马粪(M2N2)处理提升幅度最高。由核磁共振图谱可知,M2和M2N2处理均增加根际土壤难降解成分烷基碳比例、芳香基碳比例、烷基碳与烷氧基碳比值、芳香碳与总碳比值,而MN处理仅增加烷基碳比例、烷氧基碳比例以及烷基碳与烷氧基碳比值。二倍量氮肥(N2)处理降低烷基碳比例、芳香碳比例和烷氧基碳比例,根际土壤难降解成分降低,不利于土壤固碳,同时证明固态^(13)C-核磁共振技术结合半定量分析能够准确地分析不同有机碳结构组分变化,深刻认识根际土壤有机碳的稳定机制。A large amount of nitrogen fertilizer and manure can be input into the arable land of black soil in agricultural production,thus resulting in a serious negative impact on the soil’s organic carbon pool.Nearly 40%of plant primary products are transferred to the soil as substantial rhizodeposits.There is also an important carbon source for the soil microorganism surrounding the root of the plant.The rhizosphere soil can be often the zone of the highest soil microbial activity,further regulating the soil carbon cycle and nutrient transformation in terrestrial ecosystems.Therefore,it is necessary to clarify the responses of soil organic carbon content and structure to the intensification of nitrogen fertilizer and manure.In this study,a 38-year(1979-2017)long-term fertilization experiment of wheat-soybean-maize rotation was conducted at Harbin County,Heilongjiang Province,China.The rhizosphere soil of soybean was collected from nine treatments,including no fertilization(CK),nitrogen fertilizer(N),two times of nitrogen fertilizer(N2),horse manure(M),two times of horse manure(M2),horse manure plus nitrogen fertilizer(MN),and two times of horse manure plus nitrogen fertilizer(M2N2).Each treatment was performed on the 36 m^(2)(4 m×9 m)plot area.The soil organic carbon and labile organic carbon were also characterized in the 0-20 cm profile soil.A carbon-13(C^(13))nuclear magnetic resonance(^(13)C-NMR)spectroscopy was used to analyze the spectral pattern of the organic carbon in the rhizosphere soil.The results showed that the organic carbon content of rhizosphere soil was higher than that in the bulk soil for most treatments.About 18.3%and 26.7%of exogenous organic carbon contents were supplemented in the MN and M2N2 treatments,respectively.The ^(13)C-NMR spectroscopy showed that there were a higher proportion of O-alkyl C and the lower proportion of aromatic C than those in the bulk soil,indicating that the soil organic carbon structures were changed by the rhizosphere effect.Furthermore,the organic carbon content of

关 键 词：氮 有机碳 有机肥 核磁共振 大豆根际 黑土 

分 类 号：S153[农业科学—土壤学]