掺混氮肥配施抑制剂对土壤氮库的调控作用  

Effects of the blended nitrogen fertilizers combined with inhibitors on soil nitrogen pools

作　　者：白杨 杨明 陈松岭[1] 朱晓晴 蒋一飞[1] 邹洪涛[1] 张玉龙[1] BAI Yang;YANG Ming;CHEN Song-ling;ZHU Xiao-qing;JIANG Yi-fei;ZOU Hong-tao;ZHANG Yu-long(College of Land and Environment,Shenyang Agricultural University/Key Laboratory of Arable Land Conservation(Northeast China),Ministry of Agriculture/National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources,Shenyang 110866,China)

机构地区：[1]沈阳农业大学土地与环境学院/农业部东北耕地保育重点实验室/土肥资源高效利用国家工程实验室

出　　处：《应用生态学报》2019年第11期3804-3810,共7页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31572206);国家科技支撑计划项目(2015BAD23B0203);辽宁省“百千万人才工程”(2016921066);辽宁省高等学校创新人才支持计划项目(RC1705580)资助~~

摘　　要：采用冬小麦盆栽试验,探讨掺混氮肥(缓释肥N∶普通尿素N=1∶1)配施氮肥抑制剂NAM对冬小麦土壤铵态氮、硝态氮、微生物生物量氮和固定态铵含量及小麦产量、氮肥利用率的影响,分析不同处理土壤矿质氮库、微生物生物量氮库和固定态铵库的动态变化特征.试验共设6个处理,不施氮肥(CK)、普通尿素(U)、掺混氮肥(MU)、MU+2.5‰NAM(MUN1)、MU+5‰NAM(MUN2)和MU+7.5‰NAM(MUN3).结果表明:与MU处理相比,MUN2和MUN3处理推迟了NH4^+-N峰值出现的时间;小麦整个生长季,添加NAM处理的土壤矿质氮平均含量比MU处理下降了5.3%~11.7%;分蘖期至抽穗期,MU处理的微生物生物量氮矿化量和矿化率分别为38.96 mg·kg^-1和91.5%,均高于U处理,而MUN1、MUN2和MUN3处理分别为58.73 mg·kg^-1和83.3%、94.20 mg·kg^-1和94.6%、104.46 mg·kg^-1和96.3%,添加NAM处理固定态铵的释放量比MU处理提高了2.83~9.19 mg·kg^-1.通径分析结果显示,与MU处理相比,添加NAM减弱了土壤NH4^+-N库对NO3^--N库的直接影响,增强了固定态铵库通过影响NH4^+-N库对NO3^--N库的间接作用.同时,MUN1、MUN2和MUN3处理的小麦籽粒产量较MU处理分别提高了31.6%、21.5%和22.9%,氮肥利用率分别提高了8.1%、13.5%和3.1%.综上,配施NAM通过对氮素释放及在土壤中转化的双重调控,延迟土壤NH4^+-N峰值出现的时间及后续向NO3^--N的转化,提高微生物生物量氮和固定态铵的供氮作用,从而提高了作物产量和氮肥利用率.Pot experiment with winter wheat was conducted to investigate the effects of blended nitrogen(N)fertilizer(slow-release fertilizer-N:urea-N=1:1)combined with N fertilizer inhibitor NAM on soil ammonium(NH4^+-N),nitrate(NO3^--N),microbial biomass nitrogen(MBN)and fixed-ammonium(FN)contents.We analyzed dynamic characteristics of soil mineral N,MBN,FN pools under different treatments.There were six treatments,including no N fertilizer(CK),conventional urea(U),blended N fertilizer(MU),MU plus 2.5‰NAM(MUN1),MU plus 5‰NAM(MUN2),and MU plus 7.5‰NAM(MUN3).Our results showed that,compared to that of MU treatment,MUN2 and MUN3 delayed the appearance time of NH4^+-N peak.Averaged across the whole wheat growing period,soil mineral N content for NAM treatments decreased by 5.3%-11.7%.From tillering to maturity stage,MBN mineralization and mineralization rates were 38.96 mg·kg^-1 and 91.5%,which was higher than that of U treatment;MBN mineralization and mineralization rates for MUN1,MUN2 and MUN3 treatments were 58.73 mg·kg^-1,83.3%,94.20 mg·kg^-1,94.6%,104.46 mg·kg^-1 and 96.3%,respectively.The FA mineralization release for NAM treatments were higher by 2.83^-9.19 mg·kg^-1 than that of MU treatment.The results of path analysis showed that NAM addition weakened the direct effect of soil NH4^+-N pool on NO3^--N pool but enhanced the indirect effects of FN pool on NO3^--N pool through affecting NH4^+-N pool.The wheat grain yields of the MUN1,MUN2 and MUN3 treatments were significantly higher by 31.6%,21.5%and 22.9%than that of MU treatment.Nitrogen use efficiencies were increased by 8.1%,13.5%and 3.1%,respectively.In summary,through double regulation for N release and transformation in soil,NAM delayed the appearance time of soil NH4^+-N peak and retarded its transformation into NO3^--N,and increased the roles of MBN and FN in supplying N,thereby increased crop yield and N-fertilizer use efficiency.

关 键 词：掺混肥 硝化抑制剂 脲酶抑制剂 土壤氮库 调控作用 

分 类 号：S51[农业科学—作物学]