Occurrence and persistence of bacterial pathogens and indicator organisms in beach sand along the California coast

This report documents the presence of fecal indicators and bacterial pathogens in sand at 53 California marine beaches using both culture-dependent and -independent (PCR and quantitative PCR [QPCR]) methods. Fecal indicator bacteria were widespread in California beach sand, with Escherichia coli and enterococci detected at 68% and 94% of the beaches surveyed, respectively. Somatic coliphages and a Bacteroidales human-specific fecal marker were detected at 43% and 13% of the beaches, respectively. Dry sand samples from almost 30% of the beaches contained at least one of the following pathogens: Salmonella spp., Campylobacter spp., Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA), which were detected at 15%, 13%, 14%, and 3% of tested beaches, respectively. Fecal indicators and pathogens were poorly correlated to one another and to land cover. Sands were dry at the time of collection, and those with relatively high moisture tended to have higher concentrations or a more frequent occurrence of both indicators and pathogens. Using culture-dependent assays, fecal indicators decayed faster than pathogens in microcosm experiments using unaltered beach sand seeded with sewage and assessed by culture-dependent assays. The following order of persistence was observed (listed from most to least persistent): Campylobacter > Salmonella > somatic coliphages > enterococci > E. coli > F(+) phages. In contrast, pathogens decayed faster than fecal indicators in culture-independent assays: enterococci > Bacteroidales human-specific marker > Salmonella > Campylobacter. Microcosm experiments demonstrated that both indicators and pathogens were mobilized by wetting with seawater. Decay rates measured by QPCR were lower than those measured with culture-dependent methods. Enterococcal persistence and possible growth were observed for wetted microcosms relative to unwetted controls.     

Transport and distribution of sediments along the Ligurian coast

A study of the granulometric, mineralogical and chemical composition of surface sediments and suspended particulate matter in the coastal area between Varazze and Cape Noli (Ligurian Sea), provided useful information on transport and sedimentation processes in the area. Sediments samples from the shelf were highly heterogeneous, ranging from pelites to sands. Minerals typical of individual river basins were found close to river mouths, indicating a limited sediment transport along the coast. Chemical and textural characteristics of the suspended particulate matter indicated that the longshore sediment transport is influenced by the presence of a submarine canyon; material coming from the east, following the Ligurian current, is partially diverted offshore along the canyon axis. The coastline pattern, some harbor artifacts, and the peculiar morphology of the shelf are all factors controlling the direction of sediment transport.     

Copepod communities in karstic mediterranean lakes along the eastern Adriatic coast

The copepod communities of karstic lakes along the eastern Adriatic coast were studied. Lakes were divided in several groups according to their morphology (deep, shallow, barrage and reservoirs), production (oligotrophic, mesotophic and eutrophic), and salinity of water: freshwater and brackish. Copidodiaptomus steueri, Eucyclops serrulatusand Macrocyclops albidus belong to the group that inhabited most of the lakes under the study, regardless of lake type. The shallow karstic lakes are usually inhabited by Thermocyclops dybowskii, T. oithonoides, Cyclops vicinus and Eudiaptomus padanus etruscus in freshwater biotopes, and Calanipedia aquaedulcis and Copidodiaptomus steueri in brackish biotopes. The last two species can also be found in deep karstic lakes with brackish water (Bacina lakes in the Neretva River delta). Species like Cyclops abyssorumcan be found in most deep freshwater lakes. Some Calanoida were recorded in only one lake, like Eudiaptomus transsylvanicusin the deep Lake Vrana on the island of Cres, or Eudiaptomus hadzici in the barrage Lake Visovac. Production of the lakes, expressed as copepod biomass, depends on lake trophy, and in some lakes also on hydrology and salinity. Most of the meso-eutrophic lakes in the study area had Calanoida dominating, while Cyclopoida dominated in some oligotrophic and eutrophic lakes as well.     

Rocky shore distribution patterns along the Somerset coast

Along the coast of Somerset, the numbers of animal and plant species progressively decline from west to east. Changes in zonation patterns thus reflect a decrease in species richness as well as the direct influences of increasing tidal range and turbidity. The patterns are also complicated by the differing rock types: quartzite to the west, limestone to the northeast with softer marls and shales inbetween. The overall appearance of some shores has changed in recent years as a result of fucoid responses to hot summers and cold winters. This has greatly influenced community structure. In contrast to the Quoddy Region (Bay of Fundy), Ascophyllum nodosum is confined to sheltered sites whilst Nucella lapillus (together with several other gastropods) becomes increasingly restricted to lower levels – especially where a fucoid canopy is present.     

Occurrence and levels of indicators and selected pathogens in different sludges and biosolids

AIMS: Determine the occurrence and levels of pathogens and indicators in raw and treated sludges and compare their persistence after two different treatments. METHODS AND RESULTS: Helminth ova, Cryptosporidium spp., Salmonella spp., enteroviruses, and bacterial and viral indicators were determined in raw sludges and biosolids produced after mesophilic and thermophilic treatments. Except Salmonella, all of the parameters were quantified. Helminth ova were found at very low concentrations even in raw sludges. Viable Cryptosporidium oocysts were still present in most samples of treated sludges. Faecal coliforms, spores of sulphite-reducing clostridia (SSRC), and somatic coliphages were the only indicators with values above their detection limits in most of the samples. CONCLUSIONS: Pathogens were still detected in some treated sludge samples. SSRC were the most resistant micro-organisms to treatments and hence may be an indicator for the reduction of protozoan oocysts. Somatic coliphages constitute an alternative as viral indicators due to their detection in sludges before and after treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: Because of the persistence of some pathogens after sludge treatments, additional indicators are needed. SSRC and somatic coliphages are good candidates. Easy and inexpensive methods for the determination of these indicators are feasible both in industrialized and developing countries.     

Occurrence of enteroviruses in marine sediment along the coast of Barcelona, Spain

A survey of the occurrence of enteroviruses in marine sediment was undertaken in an area receiving polluted effluents. Enteroviruses were detected in 21 out of 38 samples (55%). Viruses were found as far as 5 km from the shoreline and at a depth of 82 m. Multiple correlations between enteroviruses and bacteria, detected in the same samples, were computed. No correlation could be demonstrated between virus numbers and any other parameter in sediment samples collected south of Barcelona. This lack of correlation is probably due to the different decay rates shown by bacteria and viruses. In contrast, the cases where pollution resulted from a more recent deposition, as in sediment samples collected north of Barcelona, enterovirus levels were correlated with fecal streptococci levels.     

Community outreach as an iterative dialogue among scientists and communities in the Texas gulf coast region

In response to significant environmental health challenges in Southeast Texas, a National Institute for Environmental Health Sciences Center at the University of Texas Medical Branch at Galveston was created to promote and conduct inter-disciplinary research in the areas of: (1) the molecular biology of DNA repair, replication and mutagenesis, (2) asthma pathogenesis in response to oxidative stress and viral exposures, and (3) environmental toxicant biotransformation. In addition, the NIEHS Center maintains close ties with neighboring communities through an active Community Outreach & Education Program (COEP) that develops and disseminates translational materials for use in environmental health awareness outreach, toxicology consultation, K-12 curriculum enrichment and in developing site-specific Community Partnership projects. The COEP core service divisions include: Environmental Arts & Sciences, Asthma Outreach & Education, Theater Outreach & Education, and Public Forum & Toxics Assistance. Public Forums focus on the use of Augusto Boal's Forum Theater dramaturgy to include the voices and local knowledge of communities within the process of Participatory Research. Forums create the preconditions for significant partnerships that link the hazardous risk perceptions and environmental health needs of communities with the expertise of NIEHS Center investigators and translational services provided through COEP outreach programs. The Forum process also creates leadership cores within environmentally challenged communities that facilitate the ongoing translational process and maintain the vital linkage between the health needs of communities and the analytic tools and the field and clinical technologies of the environmental sciences.     

Occurrence of halotolerant/halophilic bacterial communities in deteriorated monuments

The use of traditional microbiological methods provides the isolation of a large number of heterotrophic bacteria on deteriorated monuments. However, the spectrum of isolated bacteria changed when the protocols used in studies of halophilic bacteria were applied to mural paintings, efflorescences or mineral deposits. In fact, enumeration of the heterotrophic viable bacteria indicates that the higher counts were, generally, obtained in media with 10% of salt concentration. Media with magnesium sulphate always yielded higher counts than sodium chloride, particularly in environments where magnesium salts were abundant. The predominance of bacilli communities was remarkable. Four cases, in search of halophilic bacteria, are described.     

Salinity stratified benthic macrofaunal communities and long-term monitoring along the west coast of Sweden

Benthic macrofauna was quantitatively sampled in 12 coastal areas along the west coast of Sweden in 1971–1976. The Baltic Current creates a halocline at ≈15m depth which acts as a barrier between two differently structured benthic communities, one of which has a wide extension along the coast below the halocline and the other above the halocline. Physical and chemical factors, e.g., variations in salinity and temperature, have a great influence on the faunal structure above the halocline, whereas biological processes are the main determinating factors of the faunal composition in the comparatively more stable environment below the halocline. The sub-halocline community contains significantly more species (60%), a significantly higher mean abundance (4200 compared with 2000 ind. m^?2) and a significantly greater mean biomass (146 compared with 71 g m^?2 wet wt) than that above the halocline. Diversity measured by the Shannon-Wiener formula and its evenness had approximately the same means in both these habitats, 3.3–3.7 and 0.62, respectively.Four of the areas investigated in 1976 were also studied in the 1920's by approximately the same methods. The number of species, abundance, and biomass were significantly greater in the recent samples than in those taken half a century ago. and the community structures differed between the two periods. These differences are attributed to seasonal and natural long-term changes and different methods in processing the samples obtained. It is concluded that the halocline is a habitat divider and creates a vertical discontinuity for benthic communities on the west coast of Sweden.     

Occurrence and diversity of bacterial communities in Tuber magnatum during truffle maturation

Tuber magnatum, an ascomycetous fungus and obligate ectomycorrhizal symbiont, forms hypogeous fruit bodies, commonly called Italian white truffles. The diversity of bacterial communities associated with T. magnatum truffles was investigated using culture-independent and -dependent 16S rRNA gene-based approaches. Eighteen truffles were classified in three groups, representing different degrees of ascocarp maturation, based on the percentage of asci containing mature spores. The culturable bacterial fraction was (4.17 +/- 1.61) x 10(7), (2.60 +/- 1.22) x 10(7) and (1.86 +/- 1.32) x 10(6) cfu g(-1) for immature, intermediate and mature ascocarps respectively. The total of bacteria count was two orders of magnitude higher than the cfu g(-1) count. Sequencing results from the clone library showed a significant presence of alpha-Proteobacteria (634 of the 771 total clones screened, c. 82%) affiliated with Sinorhizobium, Rhizobium and Bradyrhizobium spp. The bacterial culturable fraction was generally represented by gamma-Proteobacteria (210 of the 384 total strains isolated, c. 55%), which were mostly fluorescent pseudomonads. Fluorescent in situ hybridization confirmed that alpha-Proteobacteria (85.8%) were the predominant components of truffle bacterial communities with beta-Proteobacteria (1.5%), gamma-Proteobacteria (1.9%), Bacteroidetes (2.1%), Firmicutes (2.4%) and Actinobacteria (3%) only poorly represented. Molecular approaches made it possible to identify alpha-Proteobacteria as major constituents of a bacterial component associated with T. magnatum ascoma, independently from the degree of maturation.     

Composition and ecology of the Quercus coccifera L. communities along the eastern Adriatic coast (NE Mediterranean)

The aim of this study is to classify and describe all plant communities with Quercus coccifera covering the entire eastern Adriatic coast and islands from north Croatia to south Albania, and to relate their species composition, chorotypes and life forms to environmental factors using Pignatti ecological indicator values. From total 70 phytosociological relevés, we identified and described four floristically and ecologically distinctive vegetation communities (two new proposed subassociations, one association and stand each) using TWINSPAN and the Braun-Blanquet classification scheme. In Croatia and Montenegro, Q. coccifera is forming macchia within the Fraxino orni–Quercetum cocciferae pistacietosum lentisci. Quercus coccifera occurs only sparsely in south Croatia as a shrubland within Fraxino orni–Quercetum cocciferae nerietosum oleandri subassociation or macchia within the Erico arboreae–Arbutetum unedonis association. Despite the difference in biogeographic position and bioclimates, low shrubby Albanian Q. coccifera stands are more closely related to the Q. coccifera communities from the western Mediterranean. Eastern Adriatic communities appear exclusively within the Querceta ilicis vegetation zone and spread within the meso-Mediterranean belt. They nevertheless are an important part of the region's natural heritage and management plans must ensure that all forms of land are used in a sustainable way.     

Occurrence and densities of bacteriophages proposed as indicators and bacterial indicators in river waters from Europe and South America

AIMS: To evaluate the feasibility of bacteriophages as a complementary tool for water quality assessment in surface waters from different parts of the globe. METHODS AND RESULTS: Faecal coliform bacteria, enterococci, spores of sulphite-reducing clostridia, somatic coliphages, F-specific RNA bacteriophages and bacteriophages infecting Bacteroides fragilis were determined by standardized methods in raw sewage and in 392 samples of river water from 22 sampling sites in 10 rivers in Argentina, Colombia, France and Spain, which represent very different climatic and socio-economic conditions. The results showed that the indicators studied maintained the same relative densities in the raw sewage from the different areas. Classifying the river water samples according to the content of faecal coliform bacteria, it can be observed that the relative densities of the different bacterial indicators and bacteriophages changed according to the concentration of faecal coliform bacteria. There was a relative increase in the densities of all groups of bacteriophages and sulphite-reducing clostridia with respect to faecal coliforms and enterococci in the samples with low counts of faecal coliform bacteria. CONCLUSIONS: The numbers of bacterial indicators and bacteriophages were similar in the different geographical areas studied. Once released in rivers, the persistence of the different micro-organisms differed significantly. Bacteriophages and spores of sulphite-reducing clostridia persisted longer than faecal coliforms and enterococci. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriophages in river water samples provide additional information to that provided by bacteria about the fate of faecal micro-organisms in river water. The easy, fast and cheap methods for phage determination are feasible both in industrialized and developing countries.     

A comparative study on socio-economic indicators and viability in small-scale fisheries of six districts along the Turkish coast

The study evaluates the status of small-scale fishermen and fishing operations, using socio-economic indicators and economic viability estimates in six selected fishing areas of Turkey during the 2002–2003 fishing season. Fifty-six percent of all small-scale fishing boats investigated achieved a positive net profit, fully recovering their operational and investment costs. Considering the viability of the fishery, 56% can be considered as economically viable. Percentages of negative gross cash flow (GCF) for each of the vessels in the district was 56% in Foça, 57% in Karaburun, 15% in Mordoğan, 16% in Akyaka, 65% in Akçapınar, and 44% in Marmaris. On the other hand, when sustainability is defined with more than an economic performance ratio of 10%, only 41% of the small-scale fishing vessels seem to have shown favourable results. Criteria such as comparatively higher catch, smaller crew size and lower labour costs, structure of the fishery or misreporting might have had a slight role in affecting the overall results which indicate that livelihood and economic viability are threatened by irregular and relatively low income levels in the small-scale fisheries sector. Given the economic conditions of small-scale fishing communities, it is suggested that all persons concerned at the community, industry and government levels should take a fresh look at the problem of sustainability. As such, more attention needs to be paid to the fishery management option by looking at performance data and having long-term monitoring of the socio-economic indicators.     

Seasonal composition and spatial distribution of hyperbenthic communities along estuarine gradients in the Westerschelde

The hyperbenthic fauna of the Westerschelde estuary was sampled in spring, summer and winter of 1990 at 14 stations along the salinity gradient. Mysids dominated the hyperbenthos in each season. Other important species, either permanently (e.g. amphipods and isopods) or temporarily (e.g. fish larvae and decapod larvae) hyperbenthic, belong to a variety of faunistic groups. Spatial structure was stable through time: the estuary could be divided in the same geographically defined zones in each season. Each zone had a characteristic fauna. Gradients in salinity, dissolved oxygen and turbidity correlated strongly with the observed variation in community structure. The spatial patterns dominated over the temporal patterns, especially in the brackish part of the estuary. In the marine part, seasonal differences in the communities were more pronounced due to the occurrence of a series of temporary hyperbenthic species in spring and summer. In each season, the upstream (brackish) communities were characterized by few species occurring in very high numbers, whereas the downstream (marine) communities were composed of many species but at lower densities.     

Ammonia- and nitrite-oxidizing bacterial communities in a pilot-scale chloraminated drinking water distribution system.

Nitrification in drinking water distribution systems is a common operational problem for many utilities that use chloramines for secondary disinfection. The diversity of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) in the distribution systems of a pilot-scale chloraminated drinking water treatment system was characterized using terminal restriction fragment length polymorphism (T-RFLP) analysis and 16S rRNA gene (ribosomal DNA [rDNA]) cloning and sequencing. For ammonia oxidizers, 16S rDNA-targeted T-RFLP indicated the presence of Nitrosomonas in each of the distribution systems, with a considerably smaller peak attributable to Nitrosospira-like AOB. Sequences of AOB amplification products aligned within the Nitrosomonas oligotropha cluster and were closely related to N. oligotropha and Nitrosomonas ureae. The nitrite-oxidizing communities were comprised primarily of Nitrospira, although Nitrobacter was detected in some samples. These results suggest a possible selection of AOB related to N. oligotropha and N. ureae in chloraminated systems and demonstrate the presence of NOB, indicating a biological mechanism for nitrite loss that contributes to a reduction in nitrite-associated chloramine decay.     

Spatial distribution of bacterial communities in high-altitude freshwater wetland sediment

Sediment microorganisms play a crucial role in a variety of biogeochemical processes in freshwater ecosystems. The objective of the current study was to investigate the spatial distribution of sediment bacterial community structure in Luoshijiang Wetland, located in Yunnan–Kweichow Plateau (China). Wetland sediments at different sites and depths were collected. Clone library analysis indicates bacterial communities varied with both sampling site and sediment depth. A total of fourteen bacterial phyla were identified in sediment samples, including Proteobacteria, Acidobacteria, Actinobacteria, Armatimonadetes, Bacteroidetes, Chlorobi, Chloroflexi, Cyanobacteria, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Spirochaetes, and Verrucomicrobia. Proteobacteria (mainly Betaproteobacteria and Deltaproteobacteria) predominated in wetland sediments. Moreover, the proportions of Alphaproteobacteria, Acidobacteria, Bacteroidetes, Gemmatimonadete, and Planctomycetes were significantly correlated with chemical properties.     

The distribution of dinoflagellate cysts along the Galician (NW Spain) coast

We have studied the distribution of dinoflagellate cysts along10 Galician rías and part of their adjacent continentalshelf. Cyst abundance in the area averaged 856 cysts ml^–1,which is of the same order of magnitude as those found in otherareas of the western European coast. It was higher in the ríasthan in the shelf, having a very heterogeneous distribution,especially in the former. Cyst assemblages in these two areaswere different, suggesting that differences are due to cystproduction rather than to accumulation. Principal componentanalysis, cluster analysis, distribution of macroscopic characteristicsof cyst populations and distribution of single species suggestthat local factors control the distribution in the rías.Nevertheless, a general pattern that splits the whole area intotwo-to the north and to the south of the ría de Camariñas-canbe distinguished. This latter trend was also observed in theshelf and, in our opinion, It should be attributed to threeconcurrent causes: the effect of different upwelling intensitiesor frequencies, the effect of the different numbers and sizesof the ría in each area, and the effect of the presenceof different water masses in these areas. The cyst distributionof a number of individual species was examined and showed threegeneral groups: species with very restricted distribution, suchas Alexandrium sp2 or Scrippsiella sp4, species with a widespreaddistribution along the rías, such as several Scrippsiellaspecies, and species mainly distributed along the shelf, suchas Gymnodinium catenatum. The distribution of cysts belongingto red tide organisms fits quite well with that of their correspondingmotile phases dunng the three previous years for most of theorganisms studied and also during the 1992–1993 period(7–8 years later), but the role of this resting stagein initiating such blooms seems to be highly variable with species.     

Occurrence of bacterial indicators and bacteriophages infecting enteric bacteria in groundwater in different geographical areas

AIMS: The aim of this research was to determine the suitability of coliphages (bacteriophages) for assessing the microbial quality of groundwater. METHODS AND RESULTS: The number of several bacterial indicators (faecal coliforms, Escherichia coli, enterococci and spores of sulfite-reducing clostridia) and bacteriophages (somatic coliphages, F-specific RNA bacteriophages and bacteriophages infecting Bacteroides fragilis) were determined in groundwater of aquifers in various geographical areas. Results show that the relative abundance, determined as percentages of positive detections, of the bacterial indicators and bacteriophages varies depending on the aquifer. CONCLUSIONS: A single bacterial indicator may not be enough to assess microbiological quality in certain aquifers. One bacterial indicator and a bacteriophage parameter provide more information than two bacterial indicators. SIGNIFICANCE AND IMPACT OF THE STUDY: Coliphages (CPH) provide different information from that provided by bacterial indicators on the microbial quality of groundwater in different geographical areas. Easy, fast and inexpensive methods for the detection of CPH are feasible in both industrialized and developing countries.     

Structure of bacterial communities along a hydrocarbon contamination gradient in a coastal sediment

The bacterial diversity of a chronically oil-polluted retention basin sediment located in the Berre lagoon (Etang-de-Berre, France) was investigated. This study combines chemical and molecular approaches in order to define how the in situ petroleum hydrocarbon contamination level affects the bacterial community structure of a subsurface sediment. Hydrocarbon content analysis clearly revealed a gradient of hydrocarbon contamination in both the water and the sediment following the basin periphery from the pollution input to the lagoon water. The nC17 and pristane concentrations suggested alkane biodegradation in the sediments. These results, combined with those of terminal-restriction fragment length polymorphism analysis of the 16S rRNA genes, indicated that bacterial community structure was obviously associated with the gradient of oil contamination. The analysis of bacterial community composition revealed dominance of bacteria related to the Proteobacteria phylum (Gamma-, Delta-, Alpha-, Epsilon- and Betaproteobacteria), Bacteroidetes and Verrucomicrobium groups and Spirochaetes, Actinobacteria and Cyanobacteria phyla. The adaptation of the bacterial community to oil contamination was not characterized by dominance of known oil-degrading bacteria, because a predominance of populations associated to the sulphur cycle was observed. The input station presented particular bacterial community composition associated with a low oil concentration in the sediment, indicating the adaptation of this community to the oil contamination.