EM发酵饲料中主要微生物类群的动态变化

对EM发酵饲料中乳酸杆菌、酵母菌、大肠菌群、腐败菌等微生物类群的动态变化进行了研究。结果表明 :饲料经EM发酵后 ,乳酸杆菌大量增加 ,发酵第4天达到最大值(9.5×108CFU·g-1 饲料) ,大肠菌群与腐败菌被明显抑制。并认为细菌总数与酵母菌数量不能作为评价EM发酵饲料质量好坏的指标。     

大凌河流域典型水生植物微生物群落吸附特征试验分析

本文采用高通测序方法对大凌河流域五刺金鱼藻、格菱、狐尾藻、水蓼及芦苇5种水生植物不同季节的微生物群落进行试验分析,分析表明:藻类密度在沉水植物表层要高于浮叶植物表层,微生物群落在浮叶植物根部的结构与其表面存在明显差异。各水生植物的优势生物群落依次为变形菌、梭菌、柔膜菌、鞭脂杆菌、杆菌、疣微菌门,且各微生物群落在季节丰度上存在明显差异性。由此可见,水环境对生物群落的影响要高于植物类型。研究成果可为大凌河流域生态修复工程提供重要理论依据。     

Bioleaching of chalcocite by mixed microorganisms subjected to mutation

Mixed microorganisms with elevated activity of chalcocite-leaching were screened by mutation methods. The original microorganisms collected from acid mine drainage of different sites were mixed and then treated with mutagens NO₂⁻, diethyl sulfate (DES), UV and their combinations, respectively. Five groups of mixed microorganisms with much stronger ore-leaching ability were obtained by screening on the leaching media. Among them, group E of mixed microorganisms (treated with 1% DES for 60 min) with the best performance on chalcocite-leaching, increases the content of Cu²⁺ by 101.4% in 20 d of leaching compared with the control culture. In addition, group E is more tolerant to Cu²⁺ in media than the control without mutation treatment. Analysis for the diversity of microbial clones indicates that half of operational taxonomic units (OTUs) in group E are Acidithiobacillus ferrooxidans. These observations suggest that group E might have potentials for industrial application. Foundation item: Project(50321402) supported by the National Natural Science Foundation of China; Project(2004CB619201) supported by the Major State Basic Research and Development Program of China     

磺酰脲类除草剂的微生物降解

微生物降解是磺酰脲类除草剂降解的重要途径之一。笔者对磺酰脲类除草剂微生物降解途径及影响微生物降解的因素进行了分析，对磺酰脲类除草剂微生物降解的研究现状做了简要综述，提出了微生物降解领域的发展趋势和有待解决的问题。     

BOD微生物传感器关键技术及其发展

生化需氧量(BOD)是表征水中有机污染物含量的重要指标,对水质监测和生化过程控制具有重要意义.总结了构成BOD检测系统的各环节,阐述了BOD微生物传感器中微生物选取、固定化以及换能器等关键技术,分析了不同方法的特点,讨论了目前BOD微生物传感器在研究中遇到的主要问题,并对其发展方向进行了展望.     

Individual-based modeling of soil organic matter in NetLogo: Transparent,user-friendly,and open

Soil organic matter dynamics are essential for terrestrial ecosystem functions as they affect biogeochemical cycles and, thus, the provision of plant nutrients or the release of greenhouse gases to the atmosphere. Most of the involved processes are driven by microorganisms. To investigate and understand these processes, individual-based models allow analyzing complex microbial systems' behavior based on rules and conditions for individual entities within these systems, taking into account local interactions and individual variations. Here, we present a streamlined, user-friendly and open version of the individual-based model INDISIM-SOM, which describes the mineralization of soil carbon and nitrogen. It was implemented in NetLogo, a widely used and easily accessible software platform especially designed for individual-based simulation models. Including powerful means to observe the model behavior and a standardized documentation, this increases INDISIM-SOM's range of potential uses and users, and facilitates the exchange among soil scientists as well as between different modeling approaches.     

大数据时代对高校人才培养模式的影响——以信息系统专业为例

大数据具有数据量巨大、数据形式多样化等特点,大数据时代为教育和学习提供了丰富的信息资源,但也给教育模式和人才培养带来挑战。首先具体说明大数据时代的特点及对高校人才培养的影响,分析大数据时代对信息系统及相应人才的要求,结合教学实践研究大数据背景下信息系统专业的人才培养模式。     

苯磺隆和2,4-D胁迫对土壤微生物影响的研究

以盆栽试验研究了除草剂苯磺隆、2,4-D对石灰性褐土中土壤微生物群落的影响。结果表明,在供试浓度下,土壤微生物对两种除草剂的感应存在一定的差异性。苯磺隆高浓度处理在最初3d极显著地抑制细菌生长,之后对土壤细菌具有刺激作用,特别是培养结束时激活率还高达917.6%,低浓度处理呈极显著的刺激作用;苯磺隆对土壤放线菌具有显著的刺激作用,对土壤真菌有强烈的抑制作用,最高抑制率达100%,到培养结束时(60d)真菌数量还未恢复到对照水平。2,4-D处理对土壤放线菌具有明显的抑制、激活的波动性,对土壤细菌、真菌有强烈的抑制作用。     

陶瓷微滤膜微生物污染的实验研究

在陶瓷微滤膜过滤过程中,微生物以及其胞外聚合物在膜表面和孔道内的滋生和黏附造成二次污染,严重影响了陶瓷膜的使用效果及使用寿命。文章通过实验研究了受污染陶瓷膜的微生物污染情况。结果表明,陶瓷膜运行过程中,膜通量下降为初始计通量的40%左右停止使用,需进行反冲洗,陶瓷膜停止使用7 d以上未进行冲洗的无法直接使用,需进行进一步处理;膜通量衰减速度随温度升高而升高,夏季要明显快于冬季,在温度为15℃以下的冬季使用,受污染膜表面的微生物生长不明显,陶瓷膜可连续间歇运行,无需过多地冲洗;腐殖酸能够为滋生的微生物提供生长、繁殖的条件,是引起微生物污染的主要成分;投加适量的次氯酸钠,可有效提高膜通量,是控制膜管微生物污染的有效方法。