Transformation Dynamics and Memory Effect of Soil Amino Sugars Amended with Available Substrates
Combination of the isotope tracing technique and the identification of amino sugars is efficient to explore the microbial immobilization of extraneous nitrogen. In the present study, the transformation dynamics and memory effect of soil amino sugars amended with available substrates were investigated. The results showed that the compound-specific 15N enrichment represented the transformation pattern of individual amino sugars and the calculated 15N-labeled portion was derived from the immobilization of the extraneous NH4+. The 15N enrichment in glucosamine was increased slowly and the unlabeled glucosamine was quite stable during the accumulation of newly-synthesized portion. The transformation of muramic acid was more rapid than glucosamine in short term, but the formation of 15Nlabeled muramic acid was concomitant with the decomposition of inherent portion. It was indicated that bacteria were more competitive than fungi to assimilate liable substrates initially, but fungus growth was dominant at later stage by utilizing the intact or metabolized substrates. Furthermore, bacterial cell wall residues were easily decomposed to be involved in the soil organic matter (SOM) turnover, while fungus-derived residue was mainly contributed to the stabilization of SOM.
15N Glucose Amino sugar Dynamics Soil
Hongbo He Xudong Zhang
Key Laboratory of Terrestrial Ecological Process,Institute of Applied Ecology,Chinese Academy of Sciences Shenyang 110016,China
国际会议
杭州
英文
304-306
2009-10-10（万方平台首次上网日期，不代表论文的发表时间）