摘要
为探讨玉米秸秆分解对土壤微生物残留物积累和稳定化过程的影响,通过室内培养试验研究了玉米秸秆施入后土壤氨基糖的动态变化和粒级分布特征,利用氨基葡萄糖(Glu N)与胞壁酸(Mur A)含量的比值探讨了不同来源微生物残留物在土壤养分循环中的相对贡献。结果表明,秸秆添加有利于氨基糖在土壤中的积累,并且真菌残留物对土壤有机质积累的贡献逐渐增加。氨基糖在高有机质土壤中的积累数量显著高于低有机质土壤,但其相对增加比例低于后者。培养过程中氨基糖首先在砂粒中合成,然后由粗粒级向细粒级迁移,尤其在黑土中粉粒对氨基糖的固持能力显著高于低有机质含量的棕壤。土壤黏粒对氨基糖的保持能力最强,且细菌细胞壁残留物向黏粒中迁移的能力显著高于真菌。
The impact of maize residue decomposition on accumulation and stabilization of microbial residues in soils was investigated through laboratory incubation. Dynamics and distributions of amino sugars in soil particle size fractions were determined. Relative contribution of microbial residues to soil organic matter(SOM) accumulation was evaluated according to ratios of glucosamine and muramic acid. Results showed that the addition of maize residues was favorable for the accumulation of amino sugars in soil due to enhanced microbial utilization efficiency of substrates.With the decomposition stagnant, the relative contribution of fungi residues increased gradually. The contents of amino sugars in the black soil were larger than that in brown soil with low organic matters, but the increase rate was higher in the later. During the decomposition of maize residues, the amino sugars were synthesized in sand fraction, and then translocated from coarser fractions to finer. The high SOM content in black soil enhanced the retention of amino sugars in silt fraction. Clay fraction was with the greatest capability of sequestering amino sugars, especially fungi residues.
出处
《土壤通报》
CAS
CSCD
北大核心
2014年第6期1402-1409,共8页
Chinese Journal of Soil Science
基金
国家自然科学基金重点项目(41130524)
国家自然科学基金面上项目(41271250)资助
中国科学院战略性先导科技专项子课题(XDA05050501)
关键词
氨基糖
作物秸秆
棕壤
黑土
土壤粒级
Amino sugar
Crop residue
Brown soil
Black soil
Soil particle size fraction
