菌剂挂膜3D-RBC联合BCO工艺处理养猪沼液废水

针对养猪沼液废水寡营养、高氨氮的水质特征，该研究采用耐高氨氮、适应贫营养生长的异养硝化-好氧反硝化（Heterotrophic Nitrification-Aerobic Denitrification，以下简称HN-AD）菌挂膜启动三维结构生物转盘+生物接触氧化反应器（3D-RBC+BCO）组合工艺对沼液进行处理。该文研究了3D-RBC+BCO组合工艺在真实沼液条件下的启动过程及污染物去除效果，重点考察了溶解氧（Dissolved Oxygen，DO）浓度和C/N比2个关键因素对组合工艺污染物去除效果的影响。同时，借助高通量测序技术对DO和C/N比优化过程中微生物群落结构的变化规律进行解析。结果表明：在真实沼液条件下，采用HN-AD菌剂挂膜启动方法，仅用12和18 d就分别完成3D-RBC和BCO反应器的挂膜启动，同时组合工艺对COD、NH4+-N和TN的去除率分别稳定在94.8%、95.7%和80.1%，出水优于城镇污水厂排放一级B标准。在对3D-RBC反应器DO和C/N比的优化过程中，增设底曝后COD、NH4+-N和TN等指标的去除率分别降低了25.4%、15.4%和15.5%。高通量测序结果显示，增加底曝后3D-RBC盘片生物膜中微生物菌属的数量小幅下降，但HN-AD优势菌属的种类与丰度显著降低，导致脱氮效率下降；贫营养型Acinetobacter、Pseudomonas菌属是3D-RBC可以对真实沼液高效脱氮的关键，提高C/N比会显著降低其丰度，进而影响脱氮效果。     

添加芽孢杆菌对草鱼池塘中真核微生物的影响

为了研究添加芽孢杆菌对池塘中真核微生物群落结构和理化因子的影响,采用高通量测序技术分析了实验组(添加芽孢杆菌池塘)与对照组(普通池塘)水体真核微生物群落结构,同时分析了两组池塘的水体理化指标。结果表明:8、9月实验组池塘水体中TN、NH_4~+-N、NO_3~--N含量显著低于对照组(P0.05)。水体中梅尼小环藻(Cyclotella meneghiniana)、红囊藻(Hedriocystis)、蓝隐藻(Chroomonas)、丝孢酵母属(Trichosporon)和小环藻属(Cyclotella)真核微生物丰度显著高于对照组(P0.05)。实验组池塘水体真核微生物Chao1指数和Shannon指数显著高于对照组(P0.05)。实验结果证实:通过向池塘添加芽孢杆菌,可以改变水体中真核微生物群落的结构,从而实现对池塘理化因子的调节。研究结果对于降低水产养殖尾水对水域环境的污染具有一定的意义。     

白三叶返园对苹果园土壤微生物群落的影响

为了解苹果(Malus pumila)园中覆盖和埋置白三叶(Trifolium repens)对土壤微生物群落的影响,采用尼龙袋法将新鲜的白三叶覆盖和埋置到苹果园中,分别在白三叶降解1、3、6个月时,利用Biolog微平板法检测土壤微生物群落的功能多样性。结果表明,覆盖和埋置白三叶均可使苹果园土壤微生物代谢活性显著提高(P0.05),微生物的多样性除6个月外显著增加、丰富度显著增加,均匀度显著降低(P0.05),群落结构发生变化,且覆草处理大于埋草,同时,白三叶降解时间的长短也影响土壤微生物群落。土壤微生物群落主成分分析结果显示,不同返园方式间主要对羧酸类碳源的利用有差异,而导致不同降解时间土壤微生物群落代谢差异的主要是糖类。说明在苹果园覆盖和埋置白三叶可改变土壤微生物群落,而覆盖白三叶对微生物群落结构的改善情况显著优于埋置白三叶。     

Sewage sludge processing determines its impact on soil microbial community structure and function

Composting and thermal drying are amongst the most commonly used post-digestion processes for allowing sanitation and biological stabilization of sewage sludge from municipal treatment plants, and making it suitable as soil conditioner for use in agriculture. To assess the impact of sludge-derived materials on soil microbial properties, fresh (LAF), composted (LAC) and thermally dried (LAT) sludge fractions, each resulting from a different post-treatment process of a same aerobically digested sewage sludge, were added at 1% (w/w) application rate on two contrasting (a loam and a loamy sand) soils and incubated under laboratory conditions for 28 days. Soil respiration, microbial ATP content, hydrolytic activities and arginine ammonification rate were monitored throughout the incubation period. Results showed that soil biochemical variables, including the metabolic quotient (qCO₂), were markedly stimulated after sludge application, and the magnitude of this stimulatory effect was dependent on sludge type (precisely LAT > LAF > LAC), but not on soil type. This effect was related to the content of stable organic matter, which was lower in LAT. Genetic fingerprinting by PCR–DGGE revealed that compositional shifts of soil bacterial and, at greater extent, actinobacterial communities were responsive to the amendment with a differing sludge fraction. The observed time-dependent changes in the DGGE profiles of amended soils reflected the microbial turnover dependent on the sludge nutrient input, whereas no indications of adverse effects of sludge-borne contaminants were noted. Our findings indicate that composting rather thermal drying can represent a more appropriate post-digestion process to make sewage sludge suitable for use as soil conditioner in agriculture.     

祁连圆柏林地不同除草方式对杂草群落及其多样性的影响

在甘肃省张掖市龙渠祁连圆柏林内采用群落生态学方法研究了化学除草、人工除草及化学除草+人工除草对祁连圆柏林杂草群落及其多样性的影响。结果表明,化学除草试验区杂草为5科15种,人工除草试验区杂草为9科20种,化学除草+人工除草试验区杂草为6科16种,对照区杂草为14科30种。化学除草处理区的杂草物种丰富度指数、Shannon多样性指数和Shannon均匀度指数最低,人工除草处理区最高,表明化学除草对祁连圆柏林杂草多样性的影响最大。在祁连圆柏林地防除杂草,采取化学除草+人工除草的方式比较适宜。     

中草药免疫活性物质对鱼类肠道菌群群落的影响研究进展

对近年来国内外有关中草药免疫活性物质对鱼类肠道菌群群落结构的影响进行了综述,旨在为开发绿色高效、营养全面的饲料提供科学的理论依据。     

Response of the soil fungal community to multi-factor environmental changes in a temperate forest

Both environmental and climatic changes are known to influence soil microbial biomes in terrestrial ecosystems. However, there are limited data defining the interactive effects of multi-factor environmental disturbances, including N-deposition, precipitation, and air temperature, on soil fungal communities in temperate forests. A 3-year outdoor pot experiment was conducted to examine the temporal shifts of soil fungal communities in a temperate forest following N-addition, precipitation and air temperature changes. The shifts in the structure and composition of soil fungal communities were characterized by denaturing gradient gel electrophoresis and DNA sequencing. N-addition regimen induced significant alterations in the composition of soil fungal communities, and this effect was different at both higher and lower altitudes. The response of the soil fungal community to N-addition was much stronger in precipitation-reduced soils compared to soils experiencing enhanced precipitation. The combined treatment of N-addition and reduced precipitation caused more pronounced changes in the lower altitude versus those in the higher one. Certain fungal species in the subphylum Pezizomycotina and Saccharomycotina distinctively responded to N fertilization and soil water control at both altitudes. Redundancy discrimination analysis showed that changes in environmental factors and soil physicochemical properties explained 43.7% of the total variability in the soil fungal community at this forest ecosystem. Variations in the soil fungal community were significantly related to the altitude, soil temperature, total soil N content (TN) and pH value (P < 0.05). We present evidence for the interactive effects of N-addition, water manipulation and air temperature to reshape soil fungal communities in the temperate forest. Our data could provide new insights into predicting the response of soil micro-ecosystem to climatic changes.     

Associations of fish with various types of littoral habitats in reservoirs

Fish associations with different types of littoral habitats were studied in four canyon‐shaped reservoirs in the Czech Republic in years 2010 and 2011 by gillnets. Two to three habitats per reservoir–beaches (former meadows), stump fields (former forest) and rubble slopes–were defined and sampled along the longitudinal axis of reservoirs. Effects of reservoir, habitat and locality (position along longitudinal axis) on fish biomass, abundance and species structure were tested for juvenile and adult fish separately. Hierarchical analysis of variance revealed that habitats differed significantly in fish biomass and abundance. Redundancy analysis showed that analysed environmental variables had significant influence on fish community structure. Most variability in community structure was explained by reservoir and then by combination of habitat and slope steepness. Locality position had the smallest influence on community structure. For both adult and juvenile fish total abundance and biomass, the most inhabited habitat was beaches; rubble slopes were the least inhabited. Habitat associations differed among species. Among adults, bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Aspius aspius and pike Esox lucius were associated with rubble slopes. Bream, white bream, bleak Alburnus alburnus, roach, ruffe and pikeperch Sander lucioperca were associated with beaches among juveniles, whereas the only juvenile associated with rubble slopes was perch. We showed that most common species are associated with distinct habitats and also that utilisation of various littoral habitats differs in general.     

基于LEED-ND认证的绿色社区开发策略分析--以上海城市最佳实践区为例

指出了中国正处在快速城市化的阶段,绿色社区开发已成为广泛关注的议题。以上海城市最佳实践区为例,通过对LEED-ND认证指标体系的分析,探讨了在LEED-ND认证体系驱动下,城市最佳实践区在场地规划、建筑节能、可再生能源和水资源利用等方面采取的开发策略和应用的绿色技术,以期为未来绿色社区的开发建设提供参考。