水炭运筹下水稻根系对氮素吸收利用的^(15)N示踪分析  

^(15)N Tracer Analysis of Nitrogen Uptake and Utilization by Rice Roots under Water and Biochar Management

作　　者：张作合 张忠学 李铁成[1,3] 秦子元 孙迪[1,3] 宋健 ZHANG Zuohe;ZHANG Zhongxue;LI Tiecheng;QIN Ziyuan;SUN Di;SONG Jian(School of Water Conservancy and Civil Engineering,Northeast Agricultural University,Harbin 150030,China;College of Agriculture and Hydraulic Engineering,Suihua University,Suihua 152061,China;Key Laboratory of Effective Utilization of Agricultural Water Resources,Ministry of Agriculture and Rural Affairs,Northeast Agricultural University,Harbin 150030,China)

机构地区：[1]东北农业大学水利与土木工程学院,哈尔滨150030 [2]绥化学院农业与水利工程学院,绥化152061 [3]东北农业大学农业农村部农业水资源高效利用重点实验室,哈尔滨150030

出　　处：《农业机械学报》2021年第6期295-304,共10页Transactions of the Chinese Society for Agricultural Machinery

基　　金：黑龙江省省属高等学校基本科研业务费基础研究项目(YWK10236200143);国家重点研发计划项目(2016YFC0400108)。

摘　　要：为揭示水炭运筹下水稻根系对氮素的吸收利用情况,采用田间小区试验与^(15)N示踪微区结合的方法,试验设置两种灌水模式(浅湿干灌溉、常规淹灌)和4个秸秆生物炭施用水平(0、2.5、12.5、25 t/hm^(2)),以常规淹灌作为对照,研究浅湿干灌溉模式施加秸秆生物炭对水稻根系形态特征和生理特性的影响,以及根系对肥料和土壤氮素的吸收利用情况。结果表明:施加秸秆生物炭改变了水稻根系形态特征和生理特性,适量的秸秆生物炭提高了根系的主根长、根体积、根鲜质量、根系活跃吸收面积、根系伤流强度和根系活力,优化了根冠比,有利于根系对氮素的吸收;浅湿干灌溉模式水稻根系对肥料-^(15)N和土壤氮素的吸收量与根系伤流强度和根系活力呈极显著正相关(P<0.01),与活跃吸收面积呈显著正相关(P<0.05),与根冠比呈显著负相关(P<0.05);浅湿干灌溉模式根系形态特征和生理特性的变化促进了水稻根系对肥料-^(15)N和土壤氮素的吸收,提高了水稻产量和氮肥利用率。其中,浅湿干灌溉模式施加12.5 t/hm^(2)秸秆生物炭处理的水稻经济产量、氮肥吸收利用率(NUE)、氮肥农学利用率(NAE)、氮肥偏生产力(NPFP)较不施加秸秆生物炭处理分别提高了13.05%、30.54%、11.67%和13.05%。本研究可为秸秆生物炭在寒地黑土区稻田的应用提供理论依据和技术支撑。In order to reveal the nitrogen uptake and utilization of rice roots under water and biochar management,field plot experiment and^(15)N tracer micro plot were used.Two irrigation modes(dry-shallow-wet irrigation and conventional flooding irrigation)and four straw biochar application levels(0 t/hm^(2),2.5 t/hm^(2),12.5 t/hm^(2) and 25 t/hm^(2))were set up.The effects of straw biochar on the morphological and physiological characteristics of rice roots,and the absorption and utilization of fertilizer and soil nitrogen by roots under dry-shallow-wet irrigation were studied.The results showed that the application of straw biochar changed the morphological and physiological characteristics of rice roots,and the appropriate amount of straw biochar increased the main root length,root volume,root fresh weight,root active absorption area,root bleeding velocity and root activity,optimized the root-shoot ratio,which was conducive to nitrogen absorption;the uptake of fertilizer-^(15)N and soil nitrogen by rice roots under dry-shallow-wet irrigation mode was also improved.There was a significant positive correlation with root bleeding and root activity(P<0.01),a significant positive correlation with active absorption area(P<0.05),and a significant negative correlation with root-shoot ratio(P<0.05).The changes of root morphological and physiological characteristics in dry-shallow-wet irrigation mode promoted the uptake of fertilizer-^(15)N and soil nitrogen by rice roots,and improved rice yield and nitrogen use efficiency.Compared with the treatment without straw biochar,the economic yield,nitrogen absorption and utilization efficiency,agronomic utilization efficiency and partial productivity of nitrogen fertilizer in the treatment of dry-shallow-wet irrigation with 12.5 t/hm^(2) straw biochar were increased by 13.05%,30.54%,11.67%and 13.05%,respectively.The results can provide theoretical basis and technical support for the application of straw biochar in paddy field in cold and black soil region.

关 键 词：稻田 水炭运筹 根系伤流 根冠比 同位素示踪技术 

分 类 号：S511[农业科学—作物学] S143