中国东北黑土土壤剖面微生物群落碳源代谢特征

发布时间：2018-04-01 19:11

本文选题：黑土　切入点：剖面　出处：《生态学报》2016年23期

【摘要】：利用Biolog Eco微平板培养法,对中国科学院海伦农田生态系统国家野外科学观测研究站农田(CL)、恢复草地(GL)和人工林地(FL)土壤剖面不同深度土壤中微生物群落碳源代谢特征进行研究。理化性质结果显示,有机碳、全氮和碱解氮含量随深度增加逐渐减少,p H则是上层土壤低于底层。可培养微生物数量从表层(0—20 cm)到底层(180—200 cm)逐渐减少,在表层(0—20 cm)3种可培养微生物数量均为草地农田林地。可培养微生物主要生活在近地表0—60 cm土层中,在60—200cm土层中3种利用方式下可培养细菌、真菌和放线菌数量基本相同。Biolog结果显示,在0—40 cm土层中微生物群落活性最大,底层(180—200 cm)土壤微生物群落活性最小。3种利用方式剖面微生物群落Shannon多样性指数和碳源利用数量从表层到底层逐渐减少,并且与SOC和TN呈极显著正相关关系(P0.05)。与农田相比恢复草地和人工林地剖面20—40 cm土层中微生物群落对各类碳源的利用强度都较高,说明没有农业机械作业的植被自然生长条件下根系会打破原来农田中的犁底层,促进表层(0—20 cm)以下微生物群落活性。碳源利用率和主成分分析结果表明长期不同植被覆盖已经改变了剖面微生物群落碳源代谢特征,而且根系已经影响到100 cm的微生物群落,但还没有影响到180—200cm中的微生物群落。
[Abstract]:Biolog Eco microplate culture method was used. The characteristics of carbon source metabolism of microbial community in soil profile of Helene farmland ecosystem observation station of Helen, Chinese Academy of Sciences were studied in this paper. The contents of organic carbon, total nitrogen and alkali-hydrolyzed nitrogen gradually decreased with the increase of depth. The amount of culturable microorganisms decreased from 0-20 cm to 180-200 cm. The number of culturable microbes from 0 to 20 cm)3 in surface layer were all grassland farmland and woodland. The culturable microbes mainly lived in 0-60 cm soil layer near the surface, and the bacteria could be cultivated in three kinds of utilization modes in 60-200cm soil layer. The number of fungi and actinomycetes was the same. Biolog showed that the microbial community activity was the highest in 0-40 cm soil layer. Soil microbial community activity was the lowest in the bottom layer (180-200 cm). The microbial community Shannon diversity index and the amount of carbon source utilization gradually decreased from the surface layer to the bottom layer. There was a significant positive correlation with SOC and TN. Compared with farmland, the microbial communities in the 20-40 cm soil layer of grassland and artificial forest land had higher utilization intensity of various carbon sources. It shows that the root system will break the bottom of the plow in the original farmland under the condition of natural growth of vegetation without agricultural machinery operation. The results of carbon source utilization and principal component analysis showed that long-term vegetation cover had changed the characteristics of carbon source metabolism of microbial community in profile, and the root system had affected the microbial community of 100 cm. However, the microbial community in 180-200cm has not been affected.
【作者单位】：东北农业大学资源与环境学院;中国科学院东北地理与农业生态研究所海伦农田生态系统国家野外科学观测研究站;
【基金】：国家自然基金资助项目(41371296)
【分类号】：S154.3

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