Monitoring E. coli and total coliforms in natural spring water as related to recreational mountain areas

Natural spring water has unique properties, as it is rich in minerals that are considered to be beneficial to human health. A survey of the microbiological quality of natural spring water was conducted to assess possible risks from the consumption of the water by visitors in recreational mountain areas located in Seoul, South Korea. The densities of total coliforms and Escherichia coli were measured during the spring and the summer of 2002 to investigate the presence of coliform bacteria in the drinking spring waters. Total coliforms were detected in all samples and the mean density of total coliforms was up to a maximum of 228 CFU/mL. Detectable E. coli was found in 78% of all samples and the mean densities of E. coli varied from a minimum of 0 CFU/mL to a maximum of 15 CFU/mL in all samples. Malfunctioning septic systems and wildlife population appear to be the main source of E. coli contamination. Presence of E. coli in natural spring water indicates potential adverse health effects for individuals or populations exposed to this water. The fecal contaminated spring water may present an unacceptable risk to humans if it is used as raw drinking water.     

浅谈城市粪便的可持续利用

从可持续发展的概念出发提出了城市粪便可持续利用的发展战略,分析了城市粪便可持续利用存在的障碍,提出了相应的对策.     

渤、黄海沿岸几种经济贝类及其生存环境中的粪大肠菌群

报道了渤、黄海 6个重点沿岸海域 (吕泗、青岛、北戴河、盘锦、大连和庄河 )表层海水和几种经济贝类中的粪大肠菌群 (FC)检测结果。结果表明 ,16个表层海水样品中的FC含量波动范围为 <4 0～≥ 4 80 0 0 /L。 36个经济贝类样品中的FC数为 <2～≥ 2 4 0 0 /g鲜重。上述结果说明 ,渤、黄海某些重点沿岸海域 (如青岛、北戴河沿岸 )受人畜粪便等生活污水和人为活动影响较严重 ,海域环境卫生状况不容乐观 ,需加强规划和治理力度。     

基于拟杆菌16S rRNA基因进行微生物溯源的研究进展

微生物溯源方法可利用粪便中的微生物区分来自人或动物的粪便污染.其中,拟杆菌以其丰度高、不能体外繁殖和宿主特异性强等优势被广泛应用于微生物溯源研究中.本文以拟杆菌16S rRNA基因为标记物,总结了拟杆菌及其标记物在环境中的衰减、拟杆菌引物的敏感性和特异性以及分子生物学技术在微生物溯源中的运用,可为粪便污染源解析提供一定的科学参考依据.     

抗生素抗性分析法在粪便污染源示踪技术中的应用

伴随着沿海人口的递增和养殖业的发展,粪便污染已成为近岸海域污染的一个重要污染源,日益威胁着人类的生存和经济发展。抗生素抗性分析法(Antibiotic Resistance Analysis,ARA)凭借对不同物种粪便源中相同示踪因子特异性抗生素抗性的检测,可以达到识别粪便污染源的目的。作为一种经济有效的粪便污染源示踪工具,ARA研究在欧美等国已开展并得到了应用。简要介绍了ARA原理、着重阐述了ARA的应用方法学,并概括了目前ARA在国内外发展现状。以期为同领域专家学者提供参考,促进中国利用ARA法在识别粪便源技术中的应用。     

Ecosystem evolution of seal colony and the influencing factors in the 20th century on Fildes Peninsula,West Antarctica

As the topmost predator in Antarctica, the seal is a unique indicator of Antarctic environment and climate changes. In this study, we collected a sediment core from the Fildes Peninsula of West Antarctica, and used cholesterol, cholestanol, epicoprostanol, coprostanol, and seal hair numbers as the proxy indicators of seal population size and phytol as of general vegetation, and we reconstructed the 20th century history of variation of the seal population and vegetation abundance on this island. The sealing industry in the early 20th century caused the dramatic decline of seal population, and the ban of seal hunting since the 1960s led to its recovery of seal population. The seal population during the past century was primarily controlled by human activities and krill density. The reconstructed relation between seal population and vegetation abundance may oifer new insights into Antarctic environment and ecology.     

城市地表水中肠道病原微生物与粪便污染指示菌的关系研究

本研究选择肠道病毒、伤寒沙门氏菌、志贺氏菌、大肠埃希氏菌作为城市水体中典型的肠道病原微生物,分别建立起相应的实时荧光定量PCR检测方法.对水源水、景观娱乐用水以及城市河流样品进行长期监测,考察典型肠道病原微生物的分布特征和变化规律.肠道病毒在各地表水体中都有检出,浓度大都在103copy·L-1以下.大肠埃希氏菌的含量在保护良好的水体和接纳城市污水的水体中有明显差别,而伤寒沙门氏菌和志贺氏菌通常出现在受粪便污染较重的水体中.统计学的分析结果显示各种水体中的肠道病原微生物检出浓度均符合对数正态分布规律.粪便污染指示菌与肠道病毒之间不存在显著的相关性,但却能在一定程度上反映典型肠道病原菌的存在情况.在大肠菌群或粪大肠菌群浓度为104CFU·L-1以上的样品中,伤寒沙门氏菌、志贺氏菌具有较高的阳性率.     

Septic tank and agricultural non‐point source pollution within a rural watershed

This investigation addresses the problem of Non‐Point Source (NPS) pollution in the rural Lake Weatherford watershed in Parker County, Texas. This reservoir is the primary municipal water supply for the City of Weatherford, Texas. The principal method of wastewater disposal is the on‐site system or septic tanks for the small residential areas surrounding the reservoir.

Sources of NPS pollution of interest in this watershed include agricultural operations as well as the residential areas. These sites were identified with the aid of aerial photography and field investigation. Suspected NPS problems were substantiated through a sampling program involving chemical and biological testing of the reservoir. Results indicate that there is significant NPS pollution contamination of Lake Weatherford from agricultural sources and seepage from on‐site wastewater disposal systems. Excessive fecal coliform and fecal streptococcus counts (>500 bacteria/100 ml) were generally associated with rainfall events and several samples showed values > 100000 bacteria/100 ml. The fecal coliform/fecal streptococcus ratios indicated contamination from human sources, animal sources, and a combination of both. Nutrient concentrations fluctuated from quite low to high with ammonia as the most consistent problem. High ammonia values were also associated with rainfall events.     

Estimation of fecal Coliform removal from domestic sewage in two sand filter column systems

The objective of the present research is to compare fecal coliform removal from two different sand column systems treating septic tank effluent over a range of hydraulic loading rates. Drain time measurements were performed to compare the hydraulic characteristic of the column systems at different hydraulic loading rates. Biochemical oxygen demand (BOD), total suspended solids (TSS), and pH were also measured for the septic tank effluent. A removal of the order of 99% for fecal coliform, TSS, and BOD in column effluent was achieved using the sand filter columns. The ‘break‐in’ period for determining the effectiveness of the sand filter columns is also discussed.     

沼液贮存及田间施用后大肠菌群的消长动态

以猪场粪污水厌氧发酵产生的沼液为材料,分别在冬春季和夏秋季对其采用加盖和无盖2种方式贮存,定期检测沼液中大肠菌群数量;通过田间生菜种植试验,定期施用大肠菌群数量(以下均以CFU计)分别为104(WF)、105(LF)、106(MF)和107g-1(HF)的沼液,在沼液施用完毕后第3、10、17和24天检测土壤、生菜表面和生菜体内大肠菌群数量。结果表明:夏秋季大肠菌群存活时间较长,沼液无盖贮存可使大肠菌群数量减少。沼液贮存50 d后,除冬春季无盖贮存的沼液中大肠菌群数量达到GB 8978—2002《污水综合排放标准》中三级排放要求,可以排放以外,其他处理均未达到排放要求。沼液中大肠菌群数量越高,经农田施用后土壤中大肠菌群数量越多,生菜表面和体内大肠菌群数量也越高,但随时间延长大肠菌群数量变化略有不同。检测期内,WF处理农田土壤中大肠菌群数量显著低于其他处理;沼液施毕后第3天,WF处理生菜表面及体内大肠菌群数量均显著小于HF和MF处理;24 d时各处理生菜体内大肠菌群数量均检测不到,达到GB 4789.3—2010《食品安全国家标准食品微生物学检验大肠菌群计数》要求,生菜表面大肠菌群数量对数值小于3.51,但未达GB 4789.3—2010要求。