岩溶地貌部位对土壤微生物丰度与酶活性的影响

Effect of Karst Physiognomy on Soil Microbial Abundance and Enzyme Activities

以中国地质科学院岩溶地质研究所桂林丫吉岩溶试验场为研究区,单氨加氧酶的编码基因amoA的部分序列作为氨氧化细菌(AOB)指示基因,利用荧光定量PCR技术,结合平板菌落计数法和土壤酶活性测定,探讨了岩溶地貌部位及土壤成因对微生物群落丰度和酶活性的影响。结果发现,受岩溶地貌部位和土壤成因的影响,土壤酶活性、土壤微生物总数在垭口、坡地、洼地呈增加的趋势,而氨氧化细菌丰度则呈现降低的趋势。结果表明,土壤氨氧化细菌丰度与真菌数呈极其显著的正相关,而与蔗糖酶活性呈极其显著负相关。

The Yaji experimental site of Institute of Karst Geology, Chinese Academy of Geology Science, was selected as the study area to discuss the effects of karst physiognomy on soil microbial abundance and enzyme activity. The gene abundances of amoA, as the index of ammonia-oxidizing bacteria（AOB） communi- ties, were determined by real-time quantitative PCR（qPCR）, while microbial community population and soil enzymes were analyzed using dilute plate incubation counting and colorimetric methods, respectively. Results show that the enzyme activities and total microbial numbers of soils in saddle back, piedmont slope and karst depression increased while the soil AOB decreased. Moreover, the abundances of AOB communities had a significantly positive correlation with fungi, while it had a significantly negative correlation with sucrase activity.