【摘要】 为了解重金属污染土壤中微生物的群落状况,摸索土壤微生物改良方法,试验对不锈钢厂排污口周边土壤中的铅(Pb)、铬(Cr)、镍(Ni)、铜(Cu)、铁(Fe)、锌(Zn)采用火焰原子吸收光谱法进行检测,针对土壤重金属含量设计选择培养基进行微生物分离,然后采用基质解析飞行时间质谱(MALDI-TOF MS)方法对分离的微生物进行鉴定,并在重金属培养基中采用数学方法建立生长模型。结果表明,不锈钢厂污水污泥中Fe含量高达2.0×10~5 mg/kg,Cr含量也达到4.7×10~4 mg/kg。采用高Fe培养基在污染土壤中筛选到1株微生物,经质谱鉴定为希瓦氏菌;在高Cr培养基中筛选到1株微生物,经鉴定为短小芽孢菌;2株微生物在高浓度重金属盐培养基中可耐受,但无重金属高营养培养基传代培养2代后重金属耐受能力消失。更多还原

【Abstract】 To understand the community status of microorganisms in soils contaminated with heavy metal and to explore ways to improve soil by microorganisms, Pb, Cr, Ni, Cu, Fe and Zn in soils around the outfall of a stainless steel plant were detected by Fire Atomic Absorption Spectrometry(FAAS). Selective medium was designed to isolate microorganisms according to the content of heavy metals and Matrix Discrimination Time-of-Flight Mass Spectrometry(MALDI-TOF MS)was adopted to identify the microorganism, the growth model was established mathematically in heavy metal medium. The experimental results showed that the content of Fe in the sewage sludge of stainless steel plant was as high as 2.0 ×10~5 mg/kg and the Cr content also reached 4.7 ×10~4 mg/kg. A strain of microorganism was screened from contaminated soil with high Fe medium and identified as Shewanella sp. by mass spectrometry.Besides, a strain of identified as Bacillus pumilus was screened out in high Cr medium. The two strains of microorganisms could survive in medium with high concentrations of heavy metal salts, but this capability disappeared after they were subculturedin highly nutritious medium with no heavy metals.更多还原