摘要
采用2种氮源并分别加入选择性微生物抑制剂进行室内培养,通过测定样品中NH4+-N和NO3--N及土壤中氨基葡萄糖和胞壁酸含量,研究土壤微生物氮素固持时间特征及其相对贡献.结果表明,加入青链霉素明显地降低了NH4+-N的转化速率,且影响远大于真菌抑制剂放线菌酮;氨基葡萄糖和胞壁酸的相对比例急剧增加,而后趋于平衡;加入放线菌酮后NO3--N转化速率持续下降,氨基葡萄糖的合成受到抑制,但加入细菌抑制剂青链霉素对其转化无显著影响.培养初期,细菌在葡萄糖存在下能快速固持NH4+-N和NO3--N,并以NH4+-N为首选氮源;培养后期,氮转化主要为真菌所推动,且真菌对NO3--N的利用能力显著大于细菌.
In an incubation test of soil with glucose amendment, two kinds of nitrogenous fertilizer and three kinds of specific microbial biocides were applied, and the contents of soil NH4^＋-N, NO3^--N, glucosamine and muramic acid were measured to differentiate the relative contribution and timing characteristics of soil microbes in nitrogen immobilization. The results showed that penicillin and streptomycin decreased the transformation rate of NH4^＋-N markedly, with more significant effects than actidione. The amount ratio of glucosamine to muramic acid after applying penicillin and streptomycin rapidly increased first, and tended to equilibrium then. With the application of aetidione, the transformation rate of NO3^--N decreased continuously, and the synthesis of glucosamine was inhibited, while penicillin and streptomycin had no significant effects on them. At the early stage of incubation, bacteria could rapidly immobilize both NH4^＋-N and NO3^--N, with NH4^＋-N preferred, while at the later stage of incubation, fungi were the dominant contributor to nitrogen transformation, and had much stronger ability of utilizing NO3^--N than bacteria.
出处
《应用生态学报》
CAS
CSCD
北大核心
2006年第5期827-830,共4页
Chinese Journal of Applied Ecology
基金
国家自然科学基金重点项目(40535028)
中国科学院知识创新工程重要方向资助项目(KZCX3-SW-433)
