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Sixty-eight marine mammals stranded on the Oregon beaches were examined at necropsy. Gunshot was the primary cause of death in 30% of the pinnipeds examined. Bacterial infections (27%) and parasitism (27%) were also of major importance in the death and debilitation of Oregon marine mammals. Traumatic death or debilitation other than gunshot was observed in 11 animals (16%). Predation, starvation due to neonatal abandonment, viral encephalitis (presumptive diagnosis), dystocia and neoplasia were diagnosed as primary or contributory causes of stranding. 相似文献
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Shallow subtidal areas of rocky reefs in central and southern New South Wales may best be described as a mosaic of habitats, the distributions of which are seemingly related to depth, wave exposure and a number of biological processes, particularly herbivory. The Fringe habitat is generally found only in the most shallow waters. Forests of the laminarian alga Ecklonia radiata are often found at intermediate depths. In deeper, or more sheltered water, sponges, ascidians and red algae are more abundant and the abundances of sea urchins and other invertebrate grazers decline. Overlying this broad-brush pattern are patches of crustose coralline algae (the Barrens habitat), the distributions of which are not clearly related to depth. Invertebrate herbivores, and sea urchins in particular, are abundant in the Barrens habitat. The Barrens habitat was most represented at the more southern locations. At the two most northern locations, reefs were shorter in length and dominated by ascidians (Pyura species). 相似文献
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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 ml1,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 19921993 period(78 years later), but the role of this resting stagein initiating such blooms seems to be highly variable with species. 相似文献
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The effect of estuarine sediment on the thermoinactivation of poliovirus type 1 and echovirus type 1 was evaluated. Poliovirus survival was prolonged at 24 and 37 degrees C but not at 4 degrees C in the presence of sediment over the time periods observed. Further inactivation studies were performed at 50 and 55 degrees C to maximize the thermal effects, and similar protection was observed. The supernatant fluid from a mixture of seawater and sediment lacked the protective effect against thermoinactivation, suggesting that prolonged virus survival in the presence of sediment was due to adsorption to particulates. From these observations, it appears that the adsorption of enteroviruses to estuarine sediments may play a significant role in protecting them against thermoinactivation. 相似文献
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A. Costán‐Longares L. Mocé‐Llivina A. Avellón J. Jofre F. Lucena 《Journal of applied microbiology》2008,105(6):1945-1955
Aims: Update information regarding occurrence and levels of culturable enteroviruses in several types of surface polluted waters in north‐eastern Spain and determine the proportion of the different species and serotypes. Methods and Results: The best procedures on hand in our laboratory for concentrating and quantifying culturable enteroviruses from different water sample types were used. Sequencing was used for typing the virus isolates. Geometric means of enteroviruses densities expressed in plaque forming units per litre were 968 in raw sewage, 12·51 in secondary effluents, 0·017 in tertiary effluents, 0·4 in river water and 0·36 in seawater. Enterovirus densities in wastewater revealed certain seasonality with a maximum at the end of spring – beginning of the summer. Coxsackievirus B, and amid them serotype CB4, were the most abundant species and serotypes detected. Conclusions: Densities of enteroviruses in different north‐eastern Spain surface waters are similar to those present in industrialized countries with temperate climate. No wild polioviruses were detected. Distribution of species showed a clear prevalence of coxsackieviruses. Significance and Impact of the Study: Information regarding enteroviruses in this geographical area provides valuable information to estimate the risk of enteroviruses transmission through water and for complementing clinical epidemiological data. 相似文献
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A comparative study was conducted with soybean material presenting symptoms of the Diaporthe/Phomopsis complex that was collected
in two distant geographical regions of the world: Beltsville, MA, USA, and Vojvodina, Yugoslavia. Contrasting with earlier
findings, great variability in the disease symptoms was observed, and one or more Phomopsis species could be isolated from
lesions presenting similar characteristics. Among the thirty-three isolates obtained from the lesions the following species
were identified: D. phaseolorum var. caulivora, P. phaseoli (teleomorph D. phaseolorum var. sojae, rare), P. longicolla (found
for the first time on the soybean fields of Yugoslavia), Phomopsis sp., and one culture showing intermediate characters of
D. phaseolorum var. caulivora and D. phaseolorum var. sojae. Much diversity was also found in the cultural characters of the
the isolates from both localities, presumably indicating evolutionary and adaptation processes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Abstract. Data on distribution and abundance of rare plant species on isolated coastal dunes along the rocky coast of northwestern Spain were compared with the local floristic literature in order to reconstruct past distribution and local extinction of species. Species extinction was not confined to species with a narrow distribution but also included widely distributed ones. Moreover, there was no evidence of colonization. Species number was related to beach and dune area, but species differed in the minimum area required for occurrence. The largest dune reserve possible would probably be insufficient to avoid further extinctions, so also small areas containing particular species should be preserved. There was no significant relationship between abundance of species in the local dune communities and their total distribution, and there were few satellite species. The former might be attributed to low fertility and habitat diversity. 相似文献
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J Srensen 《Applied microbiology》1978,36(6):809-813
The distribution of denitrification activity in a coastal marine sediment was determined by the acetylene inhibition technique and compared to concentration profiles of NO3-, NO2-, NO, and N2O. The bulk of the denitrification activity was associated with the accumulation of NO3- in the oxidized surface zone of the sediment, but a secondary denitrification zone was occasionally found in the deeper layers where oxidized patches had been introduced by the burrowing activity of the macrofauna. Maxima of NO and N2O were not associated with the peak activity of denitrification in the surface zone but were located at the lower edge of the activity profile. Significant accumulation of NO was found at the redox transition zone towards the deeper, sulfide-rich layers. 相似文献
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Fifty soil samples of urban soils of Barcelona (Spain) were analyzed. We isolated the following keratinophilic fungi: Trichophyton ajelloi, Microsporum gypseum, Chrysosporium keratinophilum, C. evolceanui, C. tropicum, C. indicum and C. asperatum. 相似文献
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Occurrence and distribution of bacterial indicators and pathogens in canal communities along the Texas coast. 总被引:2,自引:9,他引:2 下载免费PDF全文
Increased construction of residential canal communities along the southern coastline of the United States has led to a concern about their impact on water quality. Pollution of such dead-end canals is potentially hazardous because of their heavy usage for recreational activities. Coliforms, fecal coliforms, and salmonellae in the surface water and bottom sediments of six selected residential coastal canals were monitored over a period of 17 months. No statistically significant relationship was observed between the organism concentrations and temperature, pH, turbidity, and suspended solids content of water. An inverse relationship between the concentration of indicator organism and salinity of water was found, however, to occur at a 99.9% level of significance. All of the microorganisms studied were found to be present in greater numbers in sediments than in the overlying water, often by a factor of several logs. Heavy rainfall resulted in large increases in the number of organisms in both water and sediment samples. Our results indicate that bottom sediments in the shallow canal systems can act as reservoirs of enteric bacteria, which may be resuspended in response to various environmental factors and recreational activities. 相似文献
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Yamahara KM Sassoubre LM Goodwin KD Boehm AB 《Applied and environmental microbiology》2012,78(6):1733-1745
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. 相似文献
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Increased construction of residential canal communities along the southern coastline of the United States has led to a concern about their impact on water quality. Pollution of such dead-end canals is potentially hazardous because of their heavy usage for recreational activities. Coliforms, fecal coliforms, and salmonellae in the surface water and bottom sediments of six selected residential coastal canals were monitored over a period of 17 months. No statistically significant relationship was observed between the organism concentrations and temperature, pH, turbidity, and suspended solids content of water. An inverse relationship between the concentration of indicator organism and salinity of water was found, however, to occur at a 99.9% level of significance. All of the microorganisms studied were found to be present in greater numbers in sediments than in the overlying water, often by a factor of several logs. Heavy rainfall resulted in large increases in the number of organisms in both water and sediment samples. Our results indicate that bottom sediments in the shallow canal systems can act as reservoirs of enteric bacteria, which may be resuspended in response to various environmental factors and recreational activities. 相似文献
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The effect of estuarine sediment on the thermoinactivation of poliovirus type 1 and echovirus type 1 was evaluated. Poliovirus survival was prolonged at 24 and 37 degrees C but not at 4 degrees C in the presence of sediment over the time periods observed. Further inactivation studies were performed at 50 and 55 degrees C to maximize the thermal effects, and similar protection was observed. The supernatant fluid from a mixture of seawater and sediment lacked the protective effect against thermoinactivation, suggesting that prolonged virus survival in the presence of sediment was due to adsorption to particulates. From these observations, it appears that the adsorption of enteroviruses to estuarine sediments may play a significant role in protecting them against thermoinactivation. 相似文献
16.
Evidence of anthropogenic trauma in marine mammals stranded along the central California coast, 2003–2015 下载免费PDF全文
Daniela Barcenas‐De la Cruz Eugene DeRango Shawn P. Johnson Claire A. Simeone 《Marine Mammal Science》2018,34(2):330-346
A total of 11,162 stranded marine mammals was admitted to a rehabilitation center on the central California coast between January 2003 and September 2015. Six hundred seventeen animals (6%) had evidence of anthropogenic trauma (AT). California sea lions comprised the majority (83%) of AT cases, particularly by entanglement in marine debris (n = 277) and gunshot injuries (n = 165). Guadalupe fur seals had the highest prevalence of entanglement in marine debris. Cetaceans were primarily affected by boat collisions (n = 19). The highest numbers of overall strandings were recorded in 2009 (n = 1,690) and 2015 (n = 1,666); 2009 also had the highest total number (n = 137) and prevalence (8%) of AT cases. Prevalence of fishing tackle cases increased compared to similar data from 1986 to 1998 while prevalence of gunshot cases decreased, and other causes remained static. Cases of fisheries interactions were further examined and characterized, and when direct fisheries interactions were separated from other causes of AT, fisheries interactions accounted for 50% (n = 310) of all AT cases during the study period. Direct fisheries interactions were the most common type of AT observed among stranded marine mammals in central California. Tracking AT trends is important to further understand possible causes and inform mitigation efforts. 相似文献
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AIMS: To survey the presence of indigenous and nonindigenous foodborne bacterial pathogens in displayed prepacked portions of fresh marine fish. METHODS AND RESULTS: A survey of 50 different samples of fresh marine fish (conger, swordfish, sole, grouper and whiting) was conducted over a period of 5 months. Trays of fillets and steaks were obtained at retail level and tested for foodborne bacterial pathogens. Vibrio cholerae and Salmonella were not detected. Two samples (4%) yielded Vibrio strains carrying a DNA fragment specific for Vibrio parahaemolyticus, but resulted negative to PCR amplification of the virulence-related tdh gene. Levels of motile Aeromonas ranging from 2.29 to 7.20 log CFU g(-1) were found in 31 (62%) samples. All fish portions were positive for the Aeromonas hlyA gene and 38 for both aerA and hlyA genes, which may contribute to diarrhoea-related virulence. The incidence of Listeria monocytogenes was 10%. Levels of Staphylococcus aureus lower than 2 log CFU g(-1) were found in 15 (30%) samples. Numbers of presumptive Clostridium perfringens ranging from 1.82 +/- 0.22 to 4.26 +/- 1.25 log CFU g(-1) were detected in 42 (84%) samples. Edwardsiella tarda was detected in two samples of grouper fillets. CONCLUSIONS: Displayed portions of raw fish carried bacteria that can cause foodborne disease. The risk posed by fresh fish when properly cooked is low, but high when destined to be consumed raw, undercooked or very lightly processed. SIGNIFICANCE AND IMPACT OF THE STUDY: This study revealed that raw fish sold in Spain could be a source of foodborne bacterial pathogens. Improvements in handling and processing are needed to minimize the prevalence of pathogenic bacteria. 相似文献
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Diana S. Baetscher Eric C. Anderson Elizabeth A. Gilbert‐Horvath Daniel P. Malone Emily T. Saarman Mark H. Carr John Carlos Garza 《Molecular ecology》2019,28(7):1611-1623
Marine species with pelagic larvae typically exhibit little population structure, suggesting long‐distance dispersal and high gene flow. Directly quantifying dispersal of marine fishes is challenging but important, particularly for the design of marine protected areas (MPAs). Here, we studied kelp rockfish (Sebastes atrovirens) sampled along ~25 km of coastline in a boundary current‐dominated ecosystem and used genetic parentage analysis to identify dispersal events and characterize them, because the distance between sedentary parents and their settled offspring is the lifetime dispersal distance. Large sample sizes and intensive sampling are critical for increasing the likelihood of detecting parent–offspring matches in such systems and we sampled more than 6,000 kelp rockfish and analysed them with a powerful set of 96 microhaplotype markers. We identified eight parent–offspring pairs with high confidence, including two juvenile fish that were born inside MPAs and dispersed to areas outside MPAs, and four fish born in MPAs that dispersed to nearby MPAs. Additionally, we identified 25 full‐sibling pairs, which occurred throughout the sampling area and included all possible combinations of inferred dispersal trajectories. Intriguingly, these included two pairs of young‐of‐the‐year siblings with one member each sampled in consecutive years. These sibling pairs suggest monogamy, either intentional or accidental, which has not been previously demonstrated in rockfishes. This study provides the first direct observation of larval dispersal events in a current‐dominated ecosystem and direct evidence that larvae produced within MPAs are exported both to neighbouring MPAs and to proximate areas where harvest is allowed. 相似文献
19.
A. A. Aleem 《Hydrobiologia》1990,208(1-2):7-15
Transgression on marine habitats (seagrass beds, coral reefs and mangrove stands) along the Jeddah coast and adjacent lagoons, owing to increased human activity, resulted in regression, degeneration or substitution of plant and animal communities.The effect of organic and thermal pollution on benthic life is examined. A need for baseline studies on such habitats is stressed for the identification and conservation of endangered biota. 相似文献