有机无机配施体系中有机肥腐熟程度对化肥氮利用率的影响机制  

Effects of organic fertilizer maturity degree on nitrogen utilization efficiency of chemical fertilizer

作　　者：张勇 徐智[1] 王宇蕴[1] 邓亚琴 刘美菊 尹元萍[1] 郑魁 娄义晟 赵兵 ZHANG Yong;XU Zhi;WANG Yuyun;DENG Yaqin;LIU Meiju;YIN Yuanping;ZHENG Kui;LOU Yisheng;ZHAO Bing(College of Resources and Environment,Yunnan Agricultural University,Kunming 650201,China)

机构地区：[1]云南农业大学资源与环境学院,昆明650201

出　　处：《中国生态农业学报（中英文）》2021年第6期1051-1060,共10页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(31760609);中央引导高校发展校杰出人才专项(A3012020017013);云南省万人计划青年拔尖人才项目(A3012020057)资助。

摘　　要：为探究有机肥腐熟度对配施化肥氮利用率的作用机制,利用^(15)N标记技术进行意大利生菜盆栽试验,从堆肥过程中选取不同腐熟度的有机肥[按照种子发芽指数(GI值)为50%、80%和100%进行堆肥的腐熟度区分],研究施^(15)NPK化肥(对照,CK)、^(15)NPK+GI 50%有机肥(GI50)、^(15)NPK+GI 80%有机肥(GI80)、^(15)NPK+GI 100%有机肥(GI100)4个处理对意大利生菜化肥氮的转化、吸收和利用的影响。结果表明,与CK处理相比,添加有机肥处理意大利生菜生物量、^(15)N吸收量与^(15)N利用率分别显著提高30.5%~56.1%、40.0%~91.0%和15.5%~41.8%(P<0.05),GI80处理较GI50处理生物量、^(15)N吸收量与利用率分别显著提高17.1%、31.8%和35.4%(P<0.05),GI100处理较GI50处理生物量、^(15)N吸收量与利用率分别显著提高19.6%、15.8%和22.8%(P<0.05)。试验期间,添加有机肥处理较CK处理土壤^(15)NH_(4)^(+)-N显著提高44.9%~74.2%(P<0.05),^(15)NO_(3)^(-)-N显著降低8.4%~38.1%(P<0.05),净硝化率显著降低10.8%~24.6%(P<0.05);GI80处理较GI50处理土壤^(15)NH_(4)^(+)-N提高7.9%~11.5%,^(15)NO_(3)^(-)-N显著降低18.5%~50.4%(P<0.05),净硝化率显著降低15.0%~28.2%(P<0.05);GI100处理较GI50处理土壤^(15)NH_(4)^(+)-N显著提高11.5%~26.9%(P<0.05),^(15)NO_(3)^(-)-N显著降低15.8%~22.7%(P<0.05),净硝化率显著降低12.5%~23.9%(P<0.05)。土壤微生物量氮(MB^(15)N)缓慢上升,添加有机肥处理较CK处理显著提高67.3%~94.1%(P<0.05),GI80处理较GI50处理提高6.0%~23.8%,GI100处理较GI50处理显著提高6.9%~25.5%(P<0.05)。各处理MB^(15)N占MBN的54.9%~71.6%(P<0.05)。相关分析结果表明,MB^(15)N、^(15)NH_(4)^(+)-N与^(15)N吸收量、^(15)N利用率呈现极显著正相关关系,且RDA分析结果说明MB^(15)N是影响化肥^(15)N吸收利用的关键驱动因子。因此,有机无机配施体系中适当增加有机肥的腐熟度(GI≥80%)能够明显增强土壤微生物的固氮能力,提高土壤氮素水平,减缓土壤铵态氮向硝态氮的转The application of organic fertilizers promotes efficient chemical fertilizer use,but the effects and mechanisms of organic fertilizers with different maturation degrees are unresolved.To explore the effects of applying organic fertilizer with different maturity degrees on chemical nitrogen utilization efficiency for a practice of combined organic-inorganic fertilizers application,a pot experiment of lettuce(Lactuca sativa var.ramosa Hort.)was conducted using nitrogen-15(^(15)N)tracer technology.The organic fertilizers with different maturity degrees,which indicated by the germination index of cress(Lepidium sativum L.)(GI),were applied with^(15)N-labelled chemical fertilizer.A treatment without organic fertilizer application(CK)was set up as the control and following the principle of equal nutrient and carbon input,three treatments with different maturity degrees of organic fertilizer:^(15)NPK(nitrogen-15,phosphorus,potassium)+50%GI organic fertilizer(GI50),^(15)NPK+80%GI organic fertilizer(GI80),and^(15)NPK+100%GI organic fertilizer(GI100)were tested.The results showed that,compared to CK,the GI50,GI80,and GI100 treatments significantly(P<0.05)increased lettuce biomass,^(15)N uptake and^(15)N use efficiency by 30.5%–56.1%,40.0%–91.0%,and 15.5%–41.8%,respectively.The biomass,^(15)N uptake,and^(15)N use efficiency of GI80 significantly(P<0.05)increased by 17.1%,31.8%,and 35.4%,respectively;those of GI100 significantly(P<0.05)increased by 19.6%,15.8%,and 22.8%,respectively,compared to GI50.Compared to CK,ammonium-nitrogen(^(15)NH_(4)^(+)-N)in GI50,GI80,and GI100 treatments significantly increased by 44.9%–74.2%(P<0.05),nitrate-nitrogen(^(15)NO3-N-)significantly decreased by 8.4%–38.1%(P<0.05),and net nitrification rate significantly decreased by 10.8%–24.6%(P<0.05).Compared to GI50,GI80 increased ^(15)NH_(4)^(+)-Nby 7.9%–11.5%,significantly decreased ^(15)NO3-N-and net nitrification rate by 18.5%–50.4%(P<0.05)and 15.0%–28.2%(P<0.05),respectively;GI100 significantly increased ^(15)NH_(4)^(+)-Nby 1

关 键 词：有机无机肥配施 有机肥腐熟度 化肥氮利用率 土壤氮含量 净硝化率 ^(15)N标记技术 

分 类 号：S141.4[农业科学—肥料学] S143.1[农业科学—农业基础科学]