库布齐固定沙丘土壤微生物生物量的垂直分布研究

对库布齐固定沙丘土壤微生物生物量的垂直分布研究表明:①好气性细菌生物量的垂直分布是0~0.5cm(结皮层) > 0.5~10cm > 60~70cm > 30~40cm > 150~160cm,好气性细菌生物量的峰值在0~0.5cm(结皮层);②芽孢型细菌生物量的垂直分布是0.5~10cm > 0~0.5cm > 60~70cm > 30~40cm > 150~160cm,芽孢型细菌生物量的峰值在0.5~10cm;③厌气性细菌生物量的垂直分布是30~40cm=60~70cm > 0~0.5cm=0.5~10cm=150~160cm,厌气性细菌生物量的峰值在30~40cm和60~70cm;④丝状微生物生物量的垂直分布是0~0.5cm(结皮层) > 0.5~10cm > 30~40cm > 60~70cm > 150~160cm,丝状微生物生物量的峰值在0~0.5cm(结皮层);⑤库布齐固定沙丘土壤微生物生物量、土壤酶活性和养分含量的垂直分布相一致,均随土层深度增加而递减,具有明显的层次性。

Vertical Distribution of Soil Microbial Biomass in the Stabilized Sand Dune of the Hobq Desert

Study has been conducted on the vertical distribution of soil microorganism biomass in stabilized sand dune of the Hobq Desert, Inner Mongolia, China. The biomass and number of different microbial groups, enzymic activities and fertility factors ( organic matter, total N and P ) in sand dunes were determined.The results showed, the microbial biomass in stabilized sand dune were more than that of flowing sand dune, total microbial biomass were highest in biological crust of stabilized sand dune. The vertical distribution of different microbial groups were various, the order of vertical distribution in biomass of bacteria were 0～ 0.5 cm(biological crust)>0.5～10 cm>60～70 cm>30～40 cm>150～160 cm, and the order of biomass showed the aerophile bacteria> spore-forming bacteria>anaerophile bacteria, the order of vertical distribution in biomass of filamentous microorganisms (fungi and actinomyces) were 0～0.5 cm(biological crust)>0.5～10 cm>30～40 cm>60～70 cm>150～160 cm, the biomass was decreased with depth. Total biomass of soil microorganisms in 0～10 cm was more than other soil layers, their biomass ratio between the stabilized and flowing sand dunes in 0～10 cm showed that bacteria were 4.7 times and filamentous microorganisms were 2.0 times. There are less gap in biomass than in number between bacteria and filamentous microorganisms. 　　The vertical distribution of the microorganisms and their activities in sand dunes were related to soil fertility factors.