长期施肥对旱地红壤反硝化潜势和反硝化菌的影响  

Effects of Long-term Fertilization on Denitrification Potential and Denitrifying Microorganisms in Upland Red Soils

作　　者：叶桂萍 蓝嘉惠[3] 成于恒 樊剑波 林永新[2,3] YE Guiping;LAN Jiahui;CHENG Yuheng;FAN Jianbo;LIN Yongxin(College of Geography and Oceanography,Minjiang University,Fuzhou 350108,China;Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;School of Geographical Sciences,School of Carbon Neutrality Future Technology,Fujian Normal University,Fuzhou 350117,China)

机构地区：[1]闽江学院地理与海洋学院,福州350108 [2]中国科学院南京土壤研究所,南京210008 [3]福建师范大学地理科学学院、碳中和未来技术学院,福州350117

出　　处：《亚热带资源与环境学报》2024年第4期45-52,共8页Journal of Subtropical Resources and Environment

基　　金：国家自然科学基金项目(42377301);鹰潭市学科带头人培养计划项目(202202)

摘　　要：为研究长期施肥对旱地红壤反硝化潜势和反硝化菌的影响,采集中国红壤地区有机无机肥长期定位试验土壤,采用乙炔抑制剂技术研究土壤反硝化潜势,实时荧光定量PCR技术研究土壤反硝化菌功能基因(nirK和nirS)丰度。结果表明:对照处理的反硝化潜势为18.61 ng·g^(-1)·h^(-1),长期单施化肥显著提高了红壤反硝化潜势,施用化肥+石灰和化肥+猪厩肥进一步提高了红壤反硝化潜势。与单施化肥相比,施用化肥+作物残留物(花生秸秆、水稻秸秆和萝卜菜)则对土壤反硝化潜势没有显著影响。旱地红壤nirK基因丰度显著高于nirS,长期施肥对nirK和nirS基因丰度的影响规律大致相同。其中,对照处理nirK和nirS基因丰度最高,分别达到4.39×10^(7)和8.36×10^(6) copies·g^(-1),显著高于单施化肥处理。使用化肥+石灰和化肥+猪厩肥处理的nirK和nirS丰度最低。逐步回归分析发现,pH和硝态氮分别是nirS和nirK基因丰度的关键影响因子,解释率分别达到52%和46%。旱地红壤的反硝化潜势主要受pH的影响(解释率为93%),而nirK和nirS丰度和反硝化潜势呈负相关,这可能是由于pH的主导性作用掩盖了nirK和nirS对反硝化潜势的潜在影响。To investigate the effects of long-term fertilization on denitrification potential and denitrifying bacteria in dryland red soil,soil samples were collected from a long-term organic and inorganic fertilizer field experiment in the red soil region of China.Denitrification potential was assessed using the acetylene inhibition technique,and the abundance of functional genes(nirK and nirS)of denitrifying bacteria was analyzed using real-time quantitative PCR.The results showed that the denitrification potential of the control treatment was 18.61 ng·g^(-1)·h^(-1).Long-term application of chemical fertilizers significantly increased the denitrification potential of red soil.The application of chemical fertilizers+lime and chemical fertilizers+pig manure further increased the denitrification potential of red soil.In contrast,the application of chemical fertilizers combined with crop residues(peanut straw,rice straw,and radish)had no significant effect on the denitrification potential compared to the chemical fertilizer-only treatment.The abundance of nirK gene was significantly higher than that of nirS in dryland red soil,and the effect of long-term fertilization on the abundance of nirK and nirS genes followed a similar pattern.The control treatment exhibited the highest abundance of both nirK and nirS genes,reaching 4.39×10^(7) and 8.36×10^(6) copies g^(-1),respectively,which was significantly higher than the chemical fertilizer-only treatment.The lowest abundance of nirK and nirS genes was observed in the treatments with chemical fertilizers+lime and chemical fertilizers+pig manure.Stepwise regression analysis revealed that pH and nitrate nitrogen were the primary factors influencing the abundance of nirS and nirK genes,explaining 52% and 46% of the variance respectively.The denitrification potential of dryland red soil was primarily influenced by pH(explanatory rate of 93%),and the abundance of nirK and nirS genes was negatively correlated with denitrification potential.This may be due to the dominant effect of

关 键 词：长期施肥 反硝化潜势 亚硝态氮还原基因 农田土壤 

分 类 号：S154.36[农业科学—土壤学]