河岸过滤中氨氮的削减及其浓度对细菌与氨氧化微生物的影响

通过小试滤柱模拟河岸过滤,结合荧光定量PCR和高通量测序等手段研究了河岸过滤对氨氮的削减效能和进水氨氮浓度对细菌与氨氧化微生物的影响.结果表明,低浓度（0.2 mg·L^-1）氨氮未被削减,较高浓度（1.0 mg·L^-1和2.0 mg·L^-1）氨氮的削减率可达70%.进水处细菌丰度随氨氮浓度升高而增加,细菌群落组成随氨氮浓度升高发生规律性变化.出水处氨氧化古菌（Ammonia oxidizing archaea,AOA）丰度与氨氮浓度呈负相关,氨氧化细菌（Ammonia oxidizing bacteria,AOB）丰度与氨氮浓度无显著相关关系;进水处AOA-α多样性与氨氮浓度呈正相关,但AOB-α多样性与氨氮浓度呈负相关;进水处AOA群落组成受氨氮浓度影响,而进、出水处AOB群落组成均受氨氮浓度影响.可见,进水氨氮浓度会影响河岸过滤对氨氮的削减效能,还会影响细菌、氨氧化微生物的丰度及群落结构,AOB对氨氮浓度的变化比AOA更敏感.     

Influence of floc dynamic protection layer on alleviating ultrafiltration membrane fouling induced by humic substances

Cake layer formation is inevitable over time for ultrafiltration (UF) membrane-based drinking water treatment. Although the cake layer is always considered to cause membrane fouling, it can also act as a “dynamic protection layer”, as it further adsorbs pollutants and dramatically reduces their chance of getting to the membrane surface. Here, the UF membrane fouling performance was investigated with pre-deposited loose flocs in the presence of humic acid (HA). The results showed that the floc dynamic protection layer played an important role in removing HA. The higher the solution pH, the more negative the floc charge, resulting in lower HA removal efficiency due to the electrostatic repulsion and large pore size of the floc layer. With decreasing solution pH, a positively charged floc dynamic protection layer was formed, and more HA molecules were adsorbed. The potential reasons were ascribed to the smaller floc size, greater positive charge, and higher roughness of the floc layer. However, similar membrane fouling performance was also observed for the negative and positive floc dynamic protection layers due to their strong looseness characteristics. In addition, the molecular weight (MW) distribution of HA also played an important role in UF membrane fouling behavior. For the small MW HA molecules, the chance of forming a loose cake layer was high with a negatively charged floc dynamic protection layer, while for the large MW HA molecules it was high with a positively charged floc dynamic protection layer. As a result, slight UF membrane fouling was induced.     

福建崇安─宁化地区金锡多金属成矿地球化学研究

本文较系统地研究了成矿元素。稀土元素和铅、硫、氢、氧同位素以及流体包裹体等成矿地球化学特征。探讨了成矿物质和成矿溶液来源。研究结果表明．不同成因类型矿床的成矿物质和成矿溶液来源存在很大差异。     

再论次生石英岩型非金属矿床

次生石英岩型非金属矿床明显受不同级别的火山构造控制,是中—酸性火山岩区一套很有特色的矿床组合;热源、水源、地层产状有机组合生成的环流热液是成矿的前提之一;成矿流体以重碳酸盐型、硫酸盐型为主,属中—低盐度热液;温度、pH值、fo_2等物理化学条件是矿床及矿种类刑的重要控制因素。本文在《次生石英岩容矿型非金属矿床系列的矿种、组合及其成矿作用特征》(1986)一文基础上,进一步总结这类矿床的成矿机理和地质地球化学模式。     

Shaping effects of rice,wheat, maize,and soybean seedlings on their rhizosphere microbial community

The rhizosphere microbiome plays critical roles in plant growth and is an important interface for resource exchange between plants and the soil environment. Crops at various growing stages, especially the seedling stage, have strong shaping effects on the rhizosphere microbial community, and such community reconstruction will positively feed back to the plant growth. In the present study, we analyzed the variations of bacterial and fungal communities in the rhizosphere of four crop species: rice, soybean, maize, and wheat during successive cultivations (three repeats for the seedling stages) using 16S rRNA gene and internal transcribed spacer (ITS) high-throughput sequencing. We found that the relative abundances of specific microorganisms decreased after different cultivation times, e.g., Sphingomonas, Pseudomonas, Rhodanobacter, and Caulobacter, which have been reported as plant-growth beneficial bacteria. The relative abundances of potential plant pathogenic fungi Myrothecium and Ascochyta increased with the successive cultivation times. The co-occurrence network analysis showed that the bacterial and fungal communities under maize were much more stable than those under rice, soybean, and wheat. The present study explored the characteristics of bacteria and fungi in crop seedling rhizosphere and indicated that the characteristics of indigenous soil flora might determine the plant growth status. Further study will focus on the use of the critical microorganisms to control the growth and yield of specific crops.

     

DGGE、T-RFLP 、LH-PCR对两种活性污泥的微生物种群多样性分析的比较

采用基于PCR扩增的分子生态技术DGGE、T-RFLP和LH-PCR，对2种典型污水处理系统中的活性污泥（生活污泥、焦化污泥）进行微生物种群多样性分析；并以此比较3种技术的优劣，提出不同应用条件下研究方法的选择依据。根据实验结果：DGGE得到的条带较多，但误差来源也最多；T-RFLP技术较为灵敏，但需要选择适当的内切酶，严格控制酶切条件，并且文库比对误差较大；而LH-PCR操作简单，结果稳定性较高。虽然目前尚无法判断3种方法的准确性，但LH-PCR在活性污泥的微生物种群多样性分析中已显示出潜在优势。     

恶臭假单胞菌好氧降解高氯联苯的蛋白质组分析

利用固相pH梯度双向凝胶电泳分离恶臭假单胞菌以葡萄糖和Aroclor1260作为营养基质生长的菌株总蛋白,凝胶经银蓝显色后,采用PDQuest图像分析软件比较、分析识别差异表达蛋白,应用MOLDI-TOF-MS得到相应的肽质量指纹图谱,然后搜索数据库鉴定部分差异蛋白点.结果表明,获得了分辨率较高、重复性较好的不同营养基质条件下菌株蛋白的双向凝胶电泳图谱,比较分析共发现80个差异蛋白点,成功鉴定14个差异表达蛋白,包括应激应答蛋白、蛋白质生物合成、运载体和代谢相关酶类.提示与葡萄糖作为生长基质相比,菌体以多氯联苯作为碳源和能源生长时,产生应激,通过增强应激响应蛋白、蛋白质生物合成相关蛋白和相关代谢酶类的表达使细胞在胁迫条件下维持自身的稳定性与生长代谢.     

微电解+Fenton氧化+二级A/O组合工艺处理农药杀菌剂废水

杀菌剂生产废水含有大量三环唑、无机盐、高毒性物质和难生物降解有机物,对生化细菌有较强的抑制和毒害作用,且BOD5/COD值较小,采用传统生化处理工艺无法进行。现采用微电解、Fenton氧化和二级A/O组合工艺建成的废水处理工程,运行良好,出水各项指标达到环太湖流域排放标准DB 32/1072—2007。     

水平基因转移及其在污染修复中的应用

水平基因转移加速了部分生物体基因组的进化和革新;但随着基因改造生物的大量运用,由水平基因转移引起的生态安全问题越来越成为人们争论的焦点.由于大量异生污染物的产生,污染地区成为细菌水平基因转移的一个"热点"区域.为了实现污染地区的生物修复及强化难降解废水处理的效果,人为的制造和加快特定降解基因的水平转移被认为是解决这些问题的一个新思路.图2参57     

福建浦城一三都澳铜金银多金属成矿带成矿地球化学研究

本文校系统地研究了成矿元素及微星元素．稀土元素和铅、硫、氢、氧同位素等成矿地球化学特征．研究结果表明，研究区内成矿物质来源是多方面的；成矿过程中的介质水在成矿主要阶段是大气降水与再平衡岩浆水的混会，在成矿晚期则主要来自大气降水；成矿是多阶段的，可依据各阶段的矿化程度来确定今后应侧重的矿种．