模拟玉米秸秆及其生物炭还田对黑土有机质数量及化学结构特征的影响  

Effects of Simulated Maize Straw and Its Biochar Returning on Quantity and Chemical Structure of Organic Matter in Black Soil

作　　者：刘瑞雪 耿明昕 窦森[1] 关松[1] 李阳[1] LIU Ruixue;GENG Mingxin;DOU Sen;GUAN Song;LI Yang(College of Resources and Environment,Jilin Agricultural University,Changchun,130118,China)

机构地区：[1]吉林农业大学资源与环境学院,长春130118

出　　处：《吉林农业大学学报》2023年第1期51-60,共10页Journal of Jilin Agricultural University

基　　金：国家重点研发计划项目(2017YFD0200801);国家自然科学基金项目(42077022);吉林农业大学本科生科技创新基金项目(202010193079)。

摘　　要：通过365 d田间原位模拟试验,以典型黑土为研究对象,采用土壤腐殖质化学分组以及固态13C-核磁共振技术研究了全量(12 t/hm^(2))玉米秸秆还田至0~15 cm土层以模拟秸秆浅旋还田(SI15)、0~35 cm土层以模拟秸秆深混还田(SI35)、玉米秸秆覆盖(SM)、全量玉米秸秆制备的生物炭(BC4)以及与全量玉米秸秆相等碳量的生物炭施入量还田(BC12)至0~15 cm土层处理对土壤有机碳含量、土壤腐殖物质形成以及土壤有机质的化学结构特征的影响。结果表明:与ck相比,SI15与BC12处理分别显著提高土壤总有机碳(SOC)含量21.83%和20.34%,对SOC数量提升作用最大,其次为BC4处理。于活性有机碳而言,SI15、BC4和BC12均显著提高土壤水溶性有机碳、易氧化有机碳和微生物量碳含量。对于相对稳定的土壤腐殖物质而言,不同秸秆还田方式均显著增加胡敏素(HM)和胡敏酸(HA)含量(SI35处理HA除外),不同秸秆还田方式之间相比,SI15、BC4和BC12处理对提高HM的作用最大。玉米秸秆及其制备的生物炭还田对土壤有机质(SOM)的化学结构特征影响不同,SM、SI15和SI35的玉米秸秆还田处理增强了SOM脂族性,对改善SOM品质,提升土壤肥力具有重要作用;而BC4和BC12玉米秸秆生物炭还田处理明显增强SOM的芳香性和疏水性,对于提升SOM的稳定性和固碳具有重要作用。因此,相比较而言,SI15、BC12和BC4处理更有利于提升黑土SOM数量,改善SOM品质,发挥土壤肥力提升和固碳的协同作用。因此秸秆资源需要有效利用,秸秆还田既是改善土壤有机质、保持土壤肥力,又是一种环境友好、高效、低成本的重要措施之一。Straw resources are effectively utilized,and returning straw to the field is not only an im⁃portant measure to improve soil organic matter(SOM)and maintain soil fertility,but also one of the most environmentally friendly,efficient and low-cost measures.Through the field in-situ simulation experiment for 365 d,taking the typical black soil as the research object,chemical grouping of soil humus and solid-state 13C-NMR technique was used to study the effects of total amount of corn straw(12 t/hm^(2))returning to 0-15 cm soil layer(SI15)to simulate straw shallow rotation returning,return⁃ing to the field in 0-35 cm soil layer by simulating straw deep mixing(SI35),corn straw mulching(SM),total corn straw biochar(BC4)and biochar application equal to total corn straw to 0-15 cm soil layer(BC12)treatments on soil organic carbon,soil humic matter formation and chemical structure characteristics of SOM.The results showed that compared with ck,SI15 and BC12 treatments signifi⁃cantly increased the total soil organic carbon(SOC)content by 21.83%and 20.34%,respectively,with the greatest effect on the quantity of SOC,followed by BC4 treatment.As for active organic car⁃bon,SI15,BC4 and BC12 treatments significantly increased water-soluble organic carbon,easily oxi⁃dizable organic carbon and microbial biomass carbon content in soil.In the composition of soil humic substances,different straw returning methods significantly increased the content of HM.For rela⁃tively stable soil humus,the contents of humin(HM)and humic acid(HA)were almost significantly increased by different straw returning methods(except for HA in SI35 treatment).Compared with dif⁃ferent straw returning methods,SI15,BC4 and BC12 treatments had the greatest effect on the im⁃provement of HM.The effects of simulated corn straw and its biochar on the chemical structure of SOM were different.The treatments of corn straw returning of SM,SI15 and SI35 enhanced the lipoid property of SOM.Among them,SI15 was more beneficial to improving the hydrophobicity o

关 键 词：黑土 秸秆还田 生物炭 土壤有机碳 腐殖质组成 13C核磁共振 

分 类 号：S153.6[农业科学—土壤学]