Short-term response of soil microbial respiration,enzyme activities,bacteria population and PCR-DGGE profiles of bacterial communities to cefotaxime pollution
采用常规土壤酶活力测定方法、平板菌落计数法以及PCR-DGGE技术,分析头孢噻肟污染对土壤呼吸作用、部分酶活性、细菌数量以及细菌多样性的短期影响。结果表明:①头孢噻肟明显刺激处理后1~14d土壤呼吸强度,处理21d后刺激作用消失;头孢噻肟明显提高处理后1、18d土壤脲酶活性,处理后3、7d抑制作用明显;不同浓度头孢噻肟处理初期,土壤过氧化氢酶活力均受到抑制,随着培养时间的延长抑制率下降,并且低、中浓度头孢噻肟处理分别在处理后3、7d开始表现出对过氧化氢酶一定程度的刺激作用。②培养1~3d,各处理对土壤细菌数量具有一定的刺激作用,7d后中、高浓度处理对土壤细菌有一定抑制作用,而18d后各浓度处理土壤细菌数量基本恢复到对照水平。③采用Quantity One 4.6(Bio-Rad)软件,对PCR-DGGE图谱中各处理1、18d条带进行分析,发现头孢噻肟处理对样品可检测条带数没有影响,但对处理初期细菌优势种群丰度产生影响,此后逐渐恢复到对照水平。总之,头孢噻肟污染对供试土壤微生物活性、细菌数量以及优势种群的丰度具有不同程度的短期影响,但随着时间的延长,影响逐渐消失。
【英文摘要】
The short-term effect of cefotaxime at three dosage levels:low(LC,10 mg·kg-1),medium(MC,50mg·kg-1) and high(HC,200mg·kg-1) on the soil microbial respiration,enzyme activities,bacteria population and PCR-DGGE profiles of bacterial communities were studied by general measuring methods of soil respiraition and enzyme activity,plate culture count methods and PCR-DGGE techniques.Results showed that:① The soil microbial respiration was significantly stimulated by cefotaxime treated after 1 to 14 days but turned t...