Ding Xue-li, He Hong-bo, Bai Zhen, Xie Hong-tu, Zhang Bin, Zhang Xu-dong
Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Ying Yong Sheng Tai Xue Bao. 2009 Sep;20(9):2207-13.
A 38-week laboratory incubation test at 25 degrees C was conducted to examine the effects of different inorganic N supply level (0, 60.3, 167.2, and 701.9 mg N x kg(-1) soil, noted as N0, Nlow, Nmid, and Nhig, respectively) on the microbial transformation of amino sugar in a mollisol amended with maize straw. Comparing with the control, the amendment of maize straw promoted the microbial synthesis of amino sugar, and at the early period of incubation, the total amount of soil amino sugar increased with increasing inorganic N supply, being significantly higher in treatments Nmid and Nhig than in treatments N0 and Nlow. With prolonged incubation time, the total amount of soil amino sugar decreased, and the decrement was higher in treatments N0 and Nlow than in treatments Nmid and Nhig. Different inorganic N supply level also had different effects on the dynamics of various amino sugars. Muramic acid exclusively originated from bacteria was more easily to be affected by the inorganic N supply, compared with the glucosamine from fungal cell wall residues. For the amendment of higher C/N maize straw, a sufficient N supply would be necessary for the promotion of the accumulation and transformation of soil amino sugar. Soil N deficiency would restrict the growth of soil microbes, weaken the microbial synthesis of amino sugar, and decrease the captured N in microbial biomass, being not beneficial to the soil N accumulation.
进行了一项在25摄氏度下为期38周的实验室培养试验，以研究不同无机氮供应水平（0、60.3、167.2和701.9毫克氮×千克-1土壤，分别记为N0、N低、N中、N高）对添加玉米秸秆的软土中氨基糖微生物转化的影响。与对照相比，玉米秸秆的添加促进了氨基糖的微生物合成，在培养初期，土壤氨基糖总量随无机氮供应增加而增加，N中处理和N高处理显著高于N0处理和N低处理。随着培养时间延长，土壤氨基糖总量下降，N0处理和N低处理的下降幅度高于N中处理和N高处理。不同无机氮供应水平对各种氨基糖的动态变化也有不同影响。仅来源于细菌的胞壁酸比真菌细胞壁残基中的氨基葡萄糖更容易受到无机氮供应的影响。对于较高碳氮比的玉米秸秆添加物，充足的氮供应对于促进土壤氨基糖的积累和转化是必要的。土壤氮素缺乏会限制土壤微生物生长，削弱氨基糖的微生物合成，并减少微生物生物量中捕获的氮，不利于土壤氮素积累。
