褐煤风化过程中微生物群落的演替

对采自辽宁省前屯煤矿的6种不同风化程度的褐煤样品进行扫描电子显微镜观察发现:刚采掘出来的褐煤表面几乎没有微生物存在.经5个月、1年及4年堆积风化的褐煤中也只见到休眠孢子和少量菌丝.将褐煤样品在潮湿状态下培养10天后,扫描电镜观察发现:刚采出来的褐煤及经5个月风化的褐煤表面有大量放线菌生长,而且菌落周围有褐煤被降解迹象.经1年风化的褐煤中除有大量放线菌及细菌生长外,真菌也有所增加.而在经4年风化褐煤中主要是真菌明显增加.平板计数结果同样说明褐煤风化过程中微生物存在演替现象:放线菌为褐煤初期降解的主要微生物,随后是细菌,在风化程度较高的褐煤中,真菌则为优势降解菌.三株优势放线菌为诺卡氏菌(Nocardia Sp.),束丝放线菌(Actinosynnema Sp.)和链霉菌(Streptomyces sp.).两株优势细菌均为节杆菌(Arthrobacter sp.).两株曲霉为栖土曲霉(A.terricola)及褚曲霉(A.ochraceous),为褐煤风化过程的优势真菌.

MICROBIAL SUCCESSION ON LIGNITE ALONG WITH WEATHERING

Six different weathered lignite samples were examined by scanning electron microscopy. Few microorganisms were obsevred on lignit just excavated and only spores and short hyphae were observed on lignite samples excavated 5 months, 1 year and 4 years before sampling. When lignite samples were moistened with distilled water and incubated for 10 days, actinomycetes proliferated significantly on lignite samples that were just excavated or excavated 5 months before sampling. The growth of bacteria was observed on lignite samples excavated 1 year before sampling. Fungi increased in length and in number on lignite samples excavated 4 years before sampling. These findings of microbial succession on lignite samples along with weathering were consistent with results of the plate count method; actinomycetes are the first colonizers, then bacteria and fungi are the last degrader. The dominant microorganisms were Actinosynnema sp., Streptomyces sp. and Nocardia sp. among actinomycetes, two Arthrobacter sp. among bacteria and two Aspergillus sp. among fungi.