南极长城站生活污水处理前后的细菌监测

本文报道了 1 990年初南极长城站生活污水处理前和处理后 ,污水排海管道口水样粪大肠菌群和余氯含量的测定结果。结果表明 :在污水处理前 ,粪大肠菌群的数量较高 ,达 2 4 0 0 0 /1 0 0 0 ml,经处理后 ,菌量急剧地降低 ,低于有关水质规定的标准 ;菌量的降低与污水处理的加氯量有关 ,加氯越多 ,菌量下降也越多。余氯浓度过高 ,可能对近海生态造成影响 ,因此在对污水进行有效处理时 ,要尽量注意控制加氯量     

Gulf of Mexico hydrocarbon seep communities—IX. Sterol biosynthesis of seep mussels and its implications for host-symbiont association

The sterol analysis of six hydrocarbon seep mussels (mytilid II and mytilid Ib) from the Alaminos Canyon in the Gulf of Mexico is reported. The sterol composition of the mussel-symbiotic bacteria complex reflects a preponderant synthesis of 4α-methyl sterols (seep mytilid II), and a predominant biosynthesis of 4-desmethyl sterols with some amounts of 4α-methyl sterols (seep mytilid Ib). This suggests a methane-based symbiotic relationship between the mussels and methanotrophic bacteria. It also suggests that the biosynthesis of sterols in the mussel-bacteria complex is completed to the level of cholest-5-en-3ß-ol (mytilid II) or 5α-cholestan-3ß-ol (mytilid Ib).     

Preliminary evidence for human fecal contamination in corals of the Florida Keys,USA

Corals and reef environments are under increased stress from anthropogenic activities, particularly those in the vicinity of heavily populated areas such as the Florida Keys. The potential adverse impacts of wastewater can affect both the environment and human health; however, because of the high decay rate of bacterial indicators in coral reef waters it has been difficult to document the presence of microbial contaminants and to assign risks in these environments. Here we show initial evidence that microorganisms associated with human feces are concentrated along the surface of coral heads relative to the overlying water column in the Florida Keys. Bacterial indicators (fecal coliform bacteria, enterococci or Clostridium perfringens) were detected in 66.7% of the coral surface microlayer (CSM) samples at levels between five and 1000 CFU/100 ml, but were found infrequently and at low numbers in the overlying water column ( < or = 2.5 CFU/100 ml). Similarly, enterovirus nucleic acid sequences, an indicator of human-specific waste, were detected in 93.3% of the CSM samples and only once in the water column by cell culture. Results show that coral mucus may accumulate enteric microorganisms in reef environments, and may indicate a risk to public and environmental health despite low indicator levels in the surrounding water.     

Occurrence and Resistance of Pathogenic Bacteria Along the Tietê River Downstream of São Paulo in Brazil

The load of pathogenic bacteria, their fate and their dangerousness in the Tietê River were assessed along 100 km starting from the city of São Paulo, Brazil. The data were compared with those from two German rivers. High loads of pathogens were found in the Tietê River near the city of São Paulo (Escherichia coli O157:H7, Shigella flexneri, and Shigella boydii), which were absent 30 km downstream of São Paulo. The antibiotic resistances observed in the Tietê river were rather low and decreased after the major input in São Paulo to significantly lower levels about 30 km downstream. While the Brazilian isolates were more susceptible for ampicillin than the German ones, the reverse was observed for gentamycin. For optimal control of infections in humans critical areas where these bacteria survived longer and their elimination mechanisms should be identified as well as the extent and the origin of antibiotic resistance should be determined.     

发光细菌在渔业水域污染物急性毒性快速检测中的应用

以明亮发光杆菌为指示生物,对渔业水域中污染物的急性毒性进行了检测,同时研究了PH值、温度对试验结果的影响。研究表明,发光细菌毒性试验是一种快速、简便的毒性测试方法,在温度20～30℃,pH6.0～9.0条件下所进行的测试,其结果与鱼类毒性试验可以互相替代。     

南极长城湾及邻近水域表水异养细菌的含量估计及相关因子分析(英)

A survey was made of the number of the heterotrophic bacteria in surface seawater of Great Wall Bay and its adjacent waters, Antarctica during the period of austral summers from Dec.1993 to Feb. 1994. The result shows that the number of the heterotrophic bacteria in the surface waterof the surveyed area is about 798 CFU. cm-3, ranging from 53 to 4 250 CFU. cm-3. Comparison of thenumbers for three months shows a declining tendency month by month. Comparing with the previous results, this one shows that the heterotrophic bacteria number changes somewhat, but slightly. It is lower than that in nearshore waters but higher than that in the open area. This shows that there is a positive correlative relationship between CFU and NH4- N, which means that heterotrophic bacteria should be an important agent in NH4-N reproduction in the environment surveyed. There is an significant negative correlation both between CFU and NOZ-N, and between CFU and PO4-P. This means that the NOZ-N, PO.-P, which were decomposed and transformed by bacteria, were used rapidly by phytoplankton.     

Uncertainty in modelling of faecal coliform overland transport associated with manure application in Maryland

Concerns for microbial safety of surface water facilitate development of predictive models that estimate concentrations and total numbers of pathogen and indicator organisms leaving manure‐fertilized fields in overland flow during runoff events. Spatial variability of bacterial concentrations in applied manure introduces high uncertainty in the model predictions. The objective of this work was to evaluate the uncertainty in model predictions of the manure‐borne bacteria overland transport caused by limited information on the spatial distribution of bacteria in surface‐applied manure. Experiments were carried out at the ARS Beltsville experimental watershed site (OPE3) in Maryland. Dairy bovine manure was applied at a 59·3 t/ha rate on the 3·55 hectare experimental field. Faecal coliform (FC) concentrations in manure measured in 2004, 2005, 2007, and 2009 varied by 4 orders of magnitude each year. Both runoff volume and FC concentrations in runoff water were monitored using a runoff flume equipped with a refrigerated pump sampler. Two runoff events occurred before the manure was incorporated into the soil. A bacteria transport add‐on module simulator of transport with infiltration and runoff (STWIR) was linked with the event‐based kinematic runoff and erosion model (KINEROS2) to simulate convective‐dispersive overland transport, bacteria release from manure, reversible attachment–detachment to soil, and surface straining of infiltrating bacteria. The model was successfully calibrated with the field experiment data. Monte Carlo simulations were carried out to account for the spatial variation in FC in applied manure and uncertainty in the FC distribution in manure caused by the small number of samples. A tenfold and twofold variation in FC concentrations in the runoff were obtained within the 90% probability interval when initial FC spatial distributions in the manure were represented by 5 and 29 samples, respectively. Copyright © 2011 John Wiley & Sons, Ltd.     

Stormflow dynamics and loads of Escherichia coli in a large mixed land use catchment

Storm events are major transporters of faecal microbial contaminants, but few studies have reported storm loads or concentration dynamics in relation to discharge or other pollutants, notably fine sediment. Episodically, high loads of faecal contamination during storm flows impact downstream uses of water bodies, particularly contact recreation and shellfish harvesting. We examined the storm dynamics of Escherichia coli, turbidity and discharge in the mixed land use Motueka catchment (2047 km²; 60% forest and 19% pasture) to gain insights into E. coli sources and transport. We also explored different approaches for calculating E. coli loads. Discharge and field turbidity were recorded continuously, and E. coli concentrations were sampled during events, over a 13‐month period near the mouth of the Motueka River. E. coli loads were estimated by interpolation, averaging estimators and by using linear regression with smearing correction of the log‐transformed variables: discharge, turbidity, and both turbidity and discharge. The annual E. coli load was dominated (～98%) by export during events. Comparison of monthly monitoring with the intensive storm monitoring campaign suggests that simple stratification of the sampling into storm and baseflow would greatly improve export estimates. E. coli peak concentrations always preceded discharge and turbidity peaks (which had similar timing). Turbidity can be a useful surrogate for faecal microbes in smaller catchments, but in the Motueka turbidity was no better for predicting E. coli concentration than discharge. Runoff from grazed pasture and direct deposition from livestock are probably the ultimate E. coli sources in the Motueka catchment. However, in‐channel stores seem to dominate E. coli dynamics during events and account for the typical feature of bacterial concentrations peaking ahead of discharge and turbidity. This study demonstrates the importance of storm events to faecal microbial loads and shows that E. coli concentration dynamics may contrast with those of turbidity. Copyright © 2009 John Wiley & Sons, Ltd.     

砂粒粒径与砂层厚度对单体筐养养殖系统中三疣梭子蟹(Portunus trituberculatus)幼蟹摄食行为与生长特性的影响研究

建立了以经过遗传改造的发光细菌Acinetobacter sp. RecA为受试物种的环境污染物遗传毒性快速检测方法,该方法最快可在3h内得到毒性评价结果。采用该方法评价了环渤海排污口12份污水样品的遗传毒性。环渤海12个排污口的污水样品均表现出了不同水平的遗传毒性,并呈现出一定的分布特征。其中,高毒水质集中出现在山东半岛污水样品中,中毒水质集中出现在辽东半岛地区,而低毒水质主要集中于京津冀地区。综上,在环渤海的污水样品遗传毒性检测中,这种新型发光细菌法具有快速、灵敏、简便等优点,为以后近海环境的水质生物毒性检测提供了参考依据,具有应用于近海环境水质快速监测与评价的潜力。     

Diet of Haplognathia ruberrima (Gnathostomulida) in a Caribbean marine mangrove

Haplognathia ruberrima is a cosmopolitan gnathostomulid species found in sulfur bacterial mats in mangroves in Guadeloupe (French West Indies). Haplognathia ruberrima presents a δ¹³C value lower than all measured meiofaunal grazers and lower than the available measured food sources of this environment. This low δ¹³C value can not be due to specific ingestion of ¹³C‐depleted methanogenic bacteria because abundances of those bacteria are reduced in surficial and deep sediments as revealed by δ¹³C of bacterial fatty acid. According to scanning electron microscope observations, no bacterial ectosymbionts were observed at the surface of the gnathostomulids, and transmission electron microscope views revealed the absence of bacterial endosymbionts. Energy‐dispersive X‐ray spectroscopy analysis detected low levels of sulfur (0.32%±0.8) in biological tissues of H. ruberrima, confirming the absence of thioautotrophic bacterial symbionts in these animals. Consequently, the low δ¹³C value of H. ruberrima can not be due to the presence of sulfur‐oxidizing symbionts but more probably to the selective and exclusive consumption of free‐living, sulfur‐oxidizing bacteria.