Sample records for lagoon buenos aires

  1. Buenos Aires - Toward Comprehensive Development and Sustainable Mobility

    NASA Astrophysics Data System (ADS)

    Kamrowska-Zaluska, Dorota

    2017-10-01

    This paper is introducing Buenos Aires’ achievements and challenges in implementing comprehensive development and integrating efficient and sustainable transport system within its urban structure. There are several important steps in this process starting from urban regeneration of Puerto Madero, the introduction and then implementation of a strategic plan Modelo territorial (2010) and of Buenos Aires’ Plan de Movilidad Sustentable (2013). The last one - Sustainable Mobility Plan helped Buenos Aires win several prestigious rewards for innovative approach to mobility and sustainable transport and leadership in combating climate change. Buenos Aires City government demonstrates strong leadership by implementing well-planned (Bus Rapid Transport) BRT solutions, stressing the importance of political will and support, flexibility and an open mind in listening to the points of view of all stakeholders involved. Buenos Aires has made a very important step toward sustainability by supporting development of more sustainable modes of transport, such as bicycle-sharing system and improving walkability of the city centre. The last initiative combined with strong focus on public spaces is adding to tourist attractiveness based on diversity of the capital of Argentina.

  2. Dengue Virus 1 Outbreak in Buenos Aires, Argentina, 2016.

    PubMed

    Tittarelli, Estefanía; Lusso, Silvina B; Goya, Stephanie; Rojo, Gabriel L; Natale, Mónica I; Viegas, Mariana; Mistchenko, Alicia S; Valinotto, Laura E

    2017-10-01

    The largest outbreak of dengue in Buenos Aires, Argentina, occurred during 2016. Phylogenetic, phylodynamic, and phylogeographic analyses of 82 samples from dengue patients revealed co-circulation of 2 genotype V dengue virus lineages, suggesting that this virus has become endemic to the Buenos Aires metropolitan area.

  3. [Hantavirus pulmonary syndrome in Buenos Aires, 2009-2014].

    PubMed

    Iglesias, Ayelén A; Bellomo, Carla M; Martínez, Valeria P

    2016-01-01

    Andes virus is the causative agent of hantavirus pulmonary syndrome (HPS) in Argentina and neighboring countries. In our country four different areas are affected: Northwest, Southwest, Central and Northeast, where distinct Andes virus genotypes were characterized. Three genotypes were described in Buenos Aires province (Central area): AND-Buenos Aires, AND-Lechiguanas and AND-Plata. In this work, we considered all HPS cases confirmed by ELISA and real time RT-PCR during the period 2009-2014 in Buenos Aires province. The annual distribution, fatality rate and geographic distribution were analyzed. We also analyzed the genotypes involved by RT-PCR and nucleotide sequencing. Finally we evaluated epidemiological data in order to establish the route of transmission. We analyzed 1386 suspect cases of hantavirus infection from Buenos Aires province and we confirmed 88 cases of Hantavirus Pulmonary Syndrome during 2009-2014. The overall average was 14.3 cases per year. The occurrence of a HPS outbreak was confirmed in Buenos Aires province during 2013, showing a 3 fold increase in case number compared to the annual average between 2009 and 2012, tending to normalize during 2014. The overall lethality was 25.6%, with a maximum value of 45.5% in 2011. Genotype analysis was performed in 30.7% of confirmed cases, AND-BsAs show the highest incidence, it was characterized in 72% of the studied cases. Epidemiological data and results of viral genome comparison strongly suggest person-to-person transmission in the three clusters of two cases described in our study.

  4. Papers Selected for Presentation at the International Symposium on Remote Sensing of Environment (16th) Held at Buenos Aires, Argentina on 2-9 June 1982. Volume 1.

    DTIC Science & Technology

    1982-06-01

    Subsurface Water Parameters Using Radiance Measurements from Space. POOP 022 Limnological Study of the Coastal Lagoon ’Coyuca de Benitez, Guerrero...unlimited. ORGANIZED BY Comisi6n Nacional de Investigaciones Espaciales Buenos Aires, Argentina Environmental Research Institute of Michigan Ann Arbor...Michigan, USA SPONSORED, IN PART, BY ARGENTINA Comando en Jefe de la Fuerza Aerea Argentina Secretarla de Planeamiento de la Presidencia de la Naci6n

  5. [Past and present of Medicina (Buenos Aires)].

    PubMed

    Pasqualini, C D; Kotsias, B A

    2000-01-01

    To celebrate the 60th anniversary of Medicina (Buenos Aires) an International Symposium was held at the National Academy of Medicine of Buenos Aires on the 6-7th of October 1999, under the title of Clinical investigation in the next millennium. This meeting was a success as evidenced by the 376 registered attendants. Sixty years of uninterrupted publication is an uncommon feat in our midst and this could be achieved on the basis of a number of factors which include, the initiative of those who founded the journal, the unfailing motivation and dedication of the Editorial Board and primarily the authors who have trusted us with their manuscripts. Of the many important papers published, we have selected a few which proved to be milestones in the development of Argentine biomedicine. It is to be hoped that the future will bring an increase in our impact index through more and even better papers eventually reflecting the authentic scientific value of our country.

  6. Melanie Klein in Buenos Aires: beginnings and developments.

    PubMed

    Etchegoyen, R Horacio; Zysman, Samuel

    2005-06-01

    In the first decades of the 20th century, Freud was known and quoted in Latin America by an elite of enlightened minds. In the 1940s a convergence took place in Buenos Aires of European exiles with local pioneers, and thus the Argentine Psychoanalytical Association was founded in 1942. Since then psychoanalysis has grown steadily and has spread into hospitals and universities, influencing culture at large. The socioeconomic situation of that time permitted this phenomenon to develop, to the astonishment of observers. In this paper the authors study the strong influence of Kleinian thought during the first 30 years of this development. The original works of local thinkers constitute the intellectual capital that sustains the idea of an 'Argentine psychoanalytic school'. During the 1970s, both society and psychoanalysis endured deep and complex changes. Lacan's teachings gained support and Klein's influence began to decline. At present the Buenos Aires Kleinians keep working, while their relationship with Lacanians and other schools is calmer. Respectful discussions became thus possible, oriented to strictly scientific differences.

  7. Genotypic diversity of Mycobacterium tuberculosis in Buenos Aires, Argentina.

    PubMed

    Monteserin, Johana; Paul, Roxana; Gravina, Elida; Reniero, Ana; Hernandez, Teresa; Mazzeo, Eduardo; Togneri, Ana; Simboli, Norberto; López, Beatriz; Couvin, David; Rastogi, Nalin; Ritacco, Viviana

    2018-04-06

    Buenos Aires is an overpopulated port city historically inhabited by people of European descent. Together with its broader metropolitan area, the city exhibits medium tuberculosis rates, and receives migrants, mainly from tuberculosis highly endemic areas of Argentina and neighboring countries. This work was aimed to gain insight into the Mycobacterium tuberculosis population structure in two suburban districts of Buenos Aires which are illustrative of the overall situation of tuberculosis in Argentina. The Lineage 4 Euro-American accounted for >99% of the 816 isolates analyzed (one per patient). Frequencies of spoligotype families were T 35.9%, LAM 33.2%, Haarlem 19.5%, S 3.2%, X 1.5%, Ural 0.7%, BOV 0.2%, Beijing 0.2%, and Cameroon 0.2%. Unknown signatures accounted for 5.3% isolates. Of 55 spoligotypes not matching any extant shared international type (SIT) in SITVIT database, 22 fitted into 15 newly-issued SITs. Certain autochthonous South American genotypes were found to be actively evolving. LAM3, which is wild type for RD rio , was the predominant LAM subfamily in both districts and the RD rio signature was rare among autochthonous, newly created, SITs and orphan patterns. Two genotypes that are rarely observed in neighboring countries ̶ SIT2/H2 and SIT159/T1 Tuscany ̶ were conspicuously represented in Argentina. The infrequent Beijing patterns belonged to Peruvian patients. We conclude that the genotype diversity observed reflects the influence of the Hispanic colonization and more recent immigration waves from Mediterranean and neighboring countries. Unlike in Brazil, the RD rio type does not play a major role in the tuberculosis epidemic in Buenos Aires. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. [The seventieth anniversary of Medicina (Buenos Aires)].

    PubMed

    Kantor, Isabel N; Kotsias, Basilio A

    2010-01-01

    The historical trajectory of Medicina (Buenos Aires) and the current challenges accompanying its seventieth birthday are briefly described. The initial objectives at its foundation were to contribute to the advance of medicine, and support both clinical and experimental research in Argentina. These objectives continue to be valid. The editorial presence of the journal continues to be necessary. It is published following the international quality standards, the peer review system, and it is indexed in the main international data bases for scientific journals.

  9. [Toxic fungi in Buenos Aires City and surroundings].

    PubMed

    Romano, Gonzalo M; Iannone, Leopoldo; Novas, María V; Carmarán, Cecilia; Romero, Andrea I; López, Silvia E; Lechner, Bernardo E

    2013-01-01

    In Facultad de Ciencias Exactas y Naturales,Universidad de Buenos Aires there is a service called Servicio de Identificación de Hongos Tóxicos, directed by researchers of the Program of Medicinal Plants and Fungi Involved in Biological Degradation (PROPLAME-PRHIDEB, CONICET) that assist hospitals and other health establishments, identifying the different samples of fungi and providing information about their toxicity, so that patients can receive the correct treatment. The objective of the present study was to analyze all the cases received from 1985 to 2012. This analysis permitted the confection of a table identifying the most common toxic species. The information gathered revealed that 47% of the patients were under 18 years of age and had eaten basidiomes; the remaining 53% were adults who insisted that they were able to distinguish edible from toxic mushrooms. Chlorophyllum molybdites turned out to be the main cause of fungal intoxication in Buenos Aires, which is commonly confused with Macrolepiota procera, an edible mushroom. In the second place Amanita phalloides was registered, an agaric known to cause severe symptoms after a long period of latency (6-10 hours), and which can lead to hepatic failure even requiring a transplant to prevent severe internal injuries or even death, is not early and correctly treated.

  10. Child feeding practices and household food insecurity among low-income mothers in Buenos Aires, Argentina.

    PubMed

    Lindsay, Ana Cristina; Ferarro, Mabel; Franchello, Alejandra; Barrera, Raul de La; Machado, Marcia Maria Tavares; Pfeiffer, Martha Erin; Peterson, Karen Eileen

    2012-03-01

    This qualitative study of low-income mothers in Buenos Aires, Argentina, examines the influence of socio-economic conditions, organizational structures, family relationships, and food insecurity on child feeding practices and weight status. Thirty-eight mothers of preschool children living in urban Buenos Aires participated in four focus group discussions. The results indicated that many mothers were aware that obesity may be detrimental to the child's health, but most of them are unclear about the specific consequences. Maternal employment, family pressures, food insecurity and financial worries seem to influence child feeding practices. These findings have important implications for developing strategies for nutritional assistance that could benefit the health of children and provide opportunities for educational programs that are directed to nutritional awareness in Buenos Aires, Argentina. The right to eat regularly and properly is an obligation of the State and must be implemented taking into account the notion of food sovereignty and respecting the importance of preserving the culture and eating habits of a country and its diverse population groups.

  11. Cryptosporidium parvum GP60 subtypes in dairy cattle from Buenos Aires, Argentina

    USDA-ARS?s Scientific Manuscript database

    Cryptosporidium parvum from 73 dairy calves less than two months old from Buenos Aires province (Argentina) were molecularly characterized using sequence analysis of the GP60 gene. Seventy five sequences were obtained, and seven different subtypes were identified, all belonging to the IIa subtype f...

  12. Pandemic (H1N1) 2009 Cases, Buenos Aires, Argentina

    PubMed Central

    Querci, Marcia; Marcone, Débora; Videla, Cristina; Martínez, Alfredo; Bonvehi, Pablo; Carballal, Guadalupe

    2010-01-01

    To determine clinical and virologic characteristics of pandemic (H1N1) 2009 in Buenos Aires, Argentina, we conducted real-time reverse transcription–PCR on samples from patients with influenza-like illness, June 11–30, 2009. Of 513 patients tested, 54% were positive for influenza virus subtype H1N1. Infection rate was lowest for patients ≥60 years of age. PMID:20113568

  13. Second Line of Defense, Port of Buenos Aires and Exolgan Container Terminal Operational Testing and Evaluation Plan, Buenos Aires, Argentina

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roberts, Bryan W.

    2012-08-23

    The Office of the Second Line of Defense (SLD) Megaports project team for Argentina will conduct operational testing and evaluation (OT&E) at Exolgan Container Terminal at the Port of Dock Sud from July 16-20, 2012; and at the Port of Buenos Aires from September 3-7, 2012. SLD is installing radiation detection equipment to screen export, import, and transshipment containers at these locations. The purpose of OT&E is to validate and baseline an operable system that meets the SLD mission and to ensure the system continues to perform as expected in an operational environment with Argentina Customs effectively adjudicating alarms.

  14. Air--sea gaseous exchange of PCB at the Venice lagoon (Italy).

    PubMed

    Manodori, L; Gambaro, A; Moret, I; Capodaglio, G; Cescon, P

    2007-10-01

    Water bodies are important storage media for persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and this function is increased in coastal regions because their inputs are higher than those to the open sea. The air-water interface is extensively involved with the global cycling of PCBs because it is the place where they accumulate due to depositional processes and where they may be emitted by gaseous exchange. In this work the parallel collection of air, microlayer and sub-superficial water samples was performed in July 2005 at a site in the Venice lagoon to evaluate the summer gaseous flux of PCBs. The total concentration of PCBs (sum of 118 congeners) in air varies from 87 to 273 pg m(-3), whereas in the operationally defined dissolved phase of microlayer and sub-superficial water samples it varies from 159 to 391 pg L(-1). No significant enrichment of dissolved PCB into the microlayer has been observed, although a preferential accumulation of most hydrophobic congeners occurs. Due to this behaviour, we believe that the modified two-layer model was the most suitable approach for the evaluation of the flux at the air-sea interface, because it takes into account the influence of the microlayer. From its application it appears that PCB volatilize from the lagoon waters with a net flux varying from 58 to 195 ng m(-2)d(-1) (uncertainty: +/-50-64%) due to the strong influence of wind speed. This flux is greater than those reported in the literature for the atmospheric deposition and rivers input and reveals that PCB are actively emitted from the Venice lagoon in summer months.

  15. The smoke episode in Buenos Aires, 15-20 April 2008

    NASA Astrophysics Data System (ADS)

    Berbery, Ernesto Hugo; Ciappesoni, Hector C.; Kalnay, Eugenia

    2008-11-01

    The smoke that affected the city of Buenos Aires and its suburbs (approximate population, 13M) in mid April 2008 was an extreme event without historical precedent. The episode resulted in an increase of health problems among the population (respiratory problems, eye irritation) and, due to poor visibility, led to hazardous driving conditions and accidents that forced the intermittent closure of major highways. The origin of the smoke was traced to pasture burning in the La Plata River delta, to the northwest of Buenos Aires. Unfortunately, the increased shifting of livestock to the La Plata River delta may result in more common smoke episodes due to associated biomass burning practices. We clarify the mechanisms that resulted in this extreme episode, including the contribution of the La Plata River local circulations to the intensity of the event. We further show its high predictability using high resolution regional model simulations and forecasts. Our results suggest that a high resolution regional model could be used to monitor and predict several days in advance the atmospheric transport of smoke. These results could have policy implications, as preventive measures on biomass burning could be put in effect when smoke from the fires is predicted to affect a densely populated area.

  16. Genetic and phenotypic variability of iris color in Buenos Aires population

    PubMed Central

    Hohl, Diana María; Bezus, Brenda; Ratowiecki, Julia; Catanesi, Cecilia Inés

    2018-01-01

    Abstract The aim of this work was to describe the phenotypic and genotypic variability related to iris color for the population of Buenos Aires province (Argentina), and to assess the usefulness of current methods of analysis for this country. We studied five Single Nucleotide Polymorphisms (SNPs) included in the IrisPlex kit, in 118 individuals, and we quantified eye color with Digital Iris Analysis Tool. The markers fit Hardy-Weinberg equilibrium for the whole sample, but not for rs12913832 within the group of brown eyes (LR=8.429; p=0.004). We found a remarkable association of HERC2 rs12913832 GG with blue color (p < 0.01) but the other markers did not show any association with iris color. The results for the Buenos Aires population differ from those of other populations of the world for these polymorphisms (p < 0,01). The differences we found might respond to the admixed ethnic composition of Argentina; therefore, methods of analysis used in European populations should be carefully applied when studying the population of Argentina. These findings reaffirm the importance of this investigation in the Argentinian population for people identification based on iris color. PMID:29658972

  17. Hepatitis C virus diversification in Argentina: comparative analysis between the large city of Buenos Aires and the small rural town of O'Brien.

    PubMed

    Golemba, Marcelo D; Culasso, Andrés C A; Villamil, Federico G; Bare, Patricia; Gadano, Adrián; Ridruejo, Ezequiel; Martinez, Alfredo; Di Lello, Federico A; Campos, Rodolfo H

    2013-01-01

    The estimated prevalence of HCV infection in Argentina is around 2%. However, higher rates of infection have been described in population studies of small urban and rural communities. The aim of this work was to compare the origin and diversification of HCV-1b in samples from two different epidemiological scenarios: Buenos Aires, a large cosmopolitan city, and O'Brien, a small rural town with a high prevalence of HCV infection. The E1/E2 and NS5B regions of the viral genome from 83 patients infected with HCV-1b were sequenced. Phylogenetic analysis and Bayesian Coalescent methods were used to study the origin and diversification of HCV-1b in both patient populations. Samples from Buenos Aires showed a polyphyletic behavior with a tMRCA around 1887-1900 and a time of spread of infection approximately 60 years ago. In contrast, samples from ÓBrien showed a monophyletic behavior with a tMRCA around 1950-1960 and a time of spread of infection more recent than in Buenos Aires, around 20-30 years ago. Phylogenetic and coalescence analysis revealed a different behavior in the epidemiological histories of Buenos Aires and ÓBrien. HCV infection in Buenos Aires shows a polyphyletic behavior and an exponential growth in two phases, whereas that in O'Brien shows a monophyletic cluster and an exponential growth in one single step with a more recent tMRCA. The polyphyletic origin and the probability of encountering susceptible individuals in a large cosmopolitan city like Buenos Aires are in agreement with a longer period of expansion. In contrast, in less populated areas such as O'Brien, the chances of HCV transmission are strongly restricted. Furthermore, the monophyletic character and the most recent time of emergence suggest that different HCV-1b ancestors (variants) that were in expansion in Buenos Aires had the opportunity to colonize and expand in O'Brien.

  18. Hepatitis C Virus Diversification in Argentina: Comparative Analysis between the Large City of Buenos Aires and the Small Rural Town of O'Brien

    PubMed Central

    Golemba, Marcelo D.; Culasso, Andrés C. A.; Villamil, Federico G.; Bare, Patricia; Gadano, Adrián; Ridruejo, Ezequiel; Martinez, Alfredo; Di Lello, Federico A.; Campos, Rodolfo H.

    2013-01-01

    Background The estimated prevalence of HCV infection in Argentina is around 2%. However, higher rates of infection have been described in population studies of small urban and rural communities. The aim of this work was to compare the origin and diversification of HCV-1b in samples from two different epidemiological scenarios: Buenos Aires, a large cosmopolitan city, and O'Brien, a small rural town with a high prevalence of HCV infection. Patients and Methods The E1/E2 and NS5B regions of the viral genome from 83 patients infected with HCV-1b were sequenced. Phylogenetic analysis and Bayesian Coalescent methods were used to study the origin and diversification of HCV-1b in both patient populations. Results Samples from Buenos Aires showed a polyphyletic behavior with a tMRCA around 1887–1900 and a time of spread of infection approximately 60 years ago. In contrast, samples from ÓBrien showed a monophyletic behavior with a tMRCA around 1950–1960 and a time of spread of infection more recent than in Buenos Aires, around 20–30 years ago. Conclusion Phylogenetic and coalescence analysis revealed a different behavior in the epidemiological histories of Buenos Aires and ÓBrien. HCV infection in Buenos Aires shows a polyphyletic behavior and an exponential growth in two phases, whereas that in O'Brien shows a monophyletic cluster and an exponential growth in one single step with a more recent tMRCA. The polyphyletic origin and the probability of encountering susceptible individuals in a large cosmopolitan city like Buenos Aires are in agreement with a longer period of expansion. In contrast, in less populated areas such as O'Brien, the chances of HCV transmission are strongly restricted. Furthermore, the monophyletic character and the most recent time of emergence suggest that different HCV-1b ancestors (variants) that were in expansion in Buenos Aires had the opportunity to colonize and expand in O’Brien. PMID:24386322

  19. [Demographic dynamics, migrants from bordering countries and economic activity in Buenos Aires].

    PubMed

    Lattes, A E; Bertoncello, R

    1997-04-01

    The growth and changes--by age, sex, and place of birth--in the structure of the total population of the Buenos Aires metropolitan area and of the subpopulation over 15 years of age and economically active are analyzed for the decade of the 1980s. Study of the economic participation of migrants and its possible influence on levels of employment or unemployment should be carried out within the framework of changes in the population's structure and economic participation. The 1981 and 1991 censuses and the Permanent Survey of Households were the sources of data. Immigration to Argentina has declined considerably in recent years, but it is still a factor in the population growth of metropolitan Buenos Aires. Between the 1981 and 1991 censuses, the population aged 15 and over grew by 10.9/1000, or a total of 827,806 people. Migrants from bordering countries increased in number (by 85,109, or 10.3%) and in proportion to the total population (from 3.9% to 4.6%). Migrant women increased at the highest rate (30.1/1000). The greatest growth occurred among men aged 40 and over and among women aged 35 and over. The growth of the economically active population over age 15 for different groups of national origin, sex, and age showed much greater heterogeneity. In 1991, women from bordering countries represented 3.8% of all women in metropolitan Buenos Aires but 5.7% of the total economically active female population and nearly 7% of the economically active female population aged 35 and over. Women from neighboring countries were responsible for 10.3% of the growth in the economically active female population aged 30-34 and 40-44 between 1981 and 1991. The absolute and relative increases in migrants from neighboring countries and their greater economic participation tend to increase the general level of economic activity.

  20. Immigration and Educational Inclusion: Preliminary Evidence from Three Schools in Buenos Aires, Argentina

    ERIC Educational Resources Information Center

    Astiz, M. Fernanda

    2015-01-01

    This exploratory comparative case study examines three schools in the Autonomous City of Buenos Aires that have a considerable number of recent immigrant students. The article illustrates how these schools advance ideas of inclusiveness and pluralism through the curriculum and educational opportunities, as mandated by the national education law of…

  1. [Recurrent wheezing: prevalence and associated factors in infants from Buenos Aires City, Argentina].

    PubMed

    Szulman, Gabriela Aída; Freilij, Héctor; Behrends, Ilse; Gentile, Ángela; Mallol, Javier

    The episodes of bronchial obstruction at early age constitute a frequent problem in Pediatrics. The aim of this study was to evaluate the prevalence of recurrent wheezing in infants in Buenos Aires City, as well as to identify any associated factors. Cross-sectional study performed from 2011 to 2012 in the Children Hospital Ricardo Gutiérrez, Buenos Aires City, as part of the International Study of Wheezing in Infants. A validated questionnaire was applied to parents of infants aged between 12 and 15 months. The prevalence of wheezing, mostly the recurrent episodes (three or more), and their probable associated factors were evaluated. Data were statistically analyzed with χ 2 , Fisher's test, binary and logistics multiple regression analysis. The significance level was 0.05. Over 1063 infants, 58.9% (confidence interval (CI) 95% 55.9-61.9) presented at least one episode of wheezing and 26.3% (CI95% 23.8-29.9) three or more episodes (recurrent wheezing). Risk factors associated to wheezing were male gender (p=0.001), six or more episodes of cold during the first year of life (p <0.0001), age at first cold <4 months (p <0.0001); pneumonia (p <0.0001) and smoking during pregnancy (tobacco) (p=0.01). For recurrent wheezing, risk factors we considered as six or more episodes of cold during the first year of life (p <0.0001), early (< 4 month of age) onset wheezing (p <0.0001) and nocturnal wheezing (p <0.0001). The prevalence of recurrent wheezing among infants in Buenos Aires Ciy was high (26.3%). Some identified associated factors can be preventable. Copyright © 2017 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

  2. The L2 Acquisition of Buenos Aires Spanish Intonation during a Study Abroad Semester

    ERIC Educational Resources Information Center

    Thornberry, Philip A.

    2014-01-01

    The present longitudinal study describes and categorizes the primary changes in L2 Spanish intonation over time by 11 learners studying abroad in Buenos Aires, Argentina for one academic semester. Via the autosegmental metrical model of analysis, this dissertation classifies intonational contours for absolute interrogatives and declarative…

  3. Earnings and Education in Argentina: An Analysis of the 1985 Buenos Aires Household Survey.

    ERIC Educational Resources Information Center

    Kugler, Bernardo; Psacharopoulos, George

    1989-01-01

    Using data from the 1985 Buenos Aires (Argentina) Household Survey of 4,500 employed individuals, earnings differences are explained by a set of individual human capital characteristics. Returns to education investments are then estimated for different levels and types of schooling. Secondary and higher education investments need to be retargeted.…

  4. Eugenics in Buenos Aires: discourses, practices, and historiography.

    PubMed

    Armus, Diego

    2016-12-01

    Since the early 1990s, a series of studies underscored the overwhelming presence of positive eugenics in modern Argentina. These works emphasized the marginal role which discourse on eugenics took on violent methods for selection. In recent years, this point of view has shifted, emphasizing the conceptual viscosity of eugenics as well as the presence of negative eugenic discourses. This paper discusses these historiographic trends, and also dwells on the narratives that those perspectives articulated in relation to the question of sterilization and regulation of marriage of those who had tuberculosis in Buenos Aires during the first half of the twentieth century. This example stresses the need to examine discourse as well as practices in understanding and making sense of the past.

  5. Neorickettsia risticii, Rickettsia sp. and Bartonella sp. in Tadarida brasiliensis bats from Buenos Aires, Argentina.

    PubMed

    Cicuttin, Gabriel L; De Salvo, María N; La Rosa, Isabel; Dohmen, Federico E Gury

    2017-06-01

    Bats are potential reservoirs of many vector-borne bacterial pathogens. The aim of the present study was to detect species of Anaplasma, Ehrlichia, Neorickettsia, Rickettsia, Borrelia and Bartonella in Brazilian free-tailed bats (Tadarida brasiliensis, Molossidae) from Buenos Aires city, Argentina. Between 2012 and 2013, 61 T. brasiliensis from urban areas of Buenos Aires city were studied. The samples were molecularly screened by PCR and sequencing. Five bats (8.2%) were positive to Neorickettsia risticii, one (1.6%) was positive to Rickettsia sp. and three bats (4.9%) to Bartonella sp. For molecular characterization, the positive samples were subjected to amplification and sequencing of a fragment of p51 gene for N. risticii, a fragment of citrate synthase gene (gltA) for Rickettsia genus and a fragment of gltA for Bartonella genus. Phylogenetic tree was constructed using the maximum-likelihood method. Phylogenetic analysis of N. risticii detect in our study revealed that it relates to findings in the USA West Coast; Rickettsia sp. detected is phylogenetically within R. bellii group, which also includes many other Rickettsia endosymbionts of insects; and Bartonella sp. found is related to various Bartonella spp. described in Vespertilionidae bats, which are phylogenetically related to Molossidae. Our results are in accordance to previous findings, which demonstrate that insectivorous bats could be infected with vector-borne bacteria representing a potential risk to public health. Future research is necessary to clarify the circulation of these pathogens in bats from Buenos Aires. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. [Health risk for the vulnerable population exposed to arsenic in the province of Buenos Aires, Argentina].

    PubMed

    Navoni, Julio A; De Pietri, Diana; Garcia, Susana; Villaamil Lepori, Edda C

    2012-01-01

    To analyze the concentration of arsenic in water collected in localities of the province of Buenos Aires, Argentina, and the epidemiological relationship of that concentration to factors of susceptibility and associated pathologies. In 152 samples from 52 localities of Buenos Aires from 2003-2008, the concentration of arsenic was quantified through the generation of hydride spectrophotometry of atomic absorption. A composite index of health (CIH) was constructed using the content of arsenic and the percentages of households with unmet basic needs and dwellings without access to the potable water. Through the CIH, risk areas associated with mortality from malignant neoplasms related to arsenic were defined. Concentrations of arsenic spanned a broad range from 0.3 to 187 mg/L, with a median of 40 mg/L. Of the samples, 82% presented levels of arsenic higher than the acceptable limit of 10 mg/L, and more than half of those came from households with potable water connections. In the departments studied, the average mortality (deaths/100 000 inhabitants) from tumors was greater in men than in women: respiratory tract (310 versus 76), urinary tract (44 versus 11), and skin (21 versus 11), respectively. The regions with greater concentrations of arsenic and of poverty, together with the lack of potable water connections, had a two-to-four times greater risk. The findings from the composite index of health summarized the health risk from exposure to arsenic for lower socioeconomic levels of the population for a broad area of the province of Buenos Aires.

  7. A palace for astronomy in Buenos Aires

    NASA Astrophysics Data System (ADS)

    Gangui, Alejandro

    2011-06-01

    In no other epoch of Western history like in the Middle Ages, cosmology was so key an element of culture and, one way or another, the motion of the heavens ended up impregnating the literature of that time. Among the most noteworthy poets we find Dante Alighieri, who became famous for his Commedia, a monumental poem written roughly between 1307 and his death in 1321, and which the critics from 16th century onwards dubbed Divina. In this and other works, Dante pictures the cosmic image for the world, summing up the current trends of Neoplatonic and Islamic traditions. The Barolo Palace in the city of Buenos Aires is a singular combination of both astronomy and the worldview displayed in Dante's poetic masterpiece. Some links of the Palace's main architectural structure with the three realms of the Comedy have been studied in the past. In this note we consider its unique astronomical flavor, an issue which has not been sufficiently emphasized yet.

  8. Urban political ecologies of informal recyclers׳ health in Buenos Aires, Argentina.

    PubMed

    Parizeau, Kate

    2015-05-01

    Buenos Aires׳ informal recyclers (cartoneros) confront multiple health hazards in their work. Based in a survey with (n=397) informal recyclers, this study establishes that these workers experience uneven health landscapes as evidenced through their health outcomes, the social determinants of their health, and their living and working environments. I argue that the analytical framework of urban political ecology can provide insights to the ways that the urban environments where cartoneros live and work are socially-constructed phenomena, drawing on concepts of crisis, metabolism, and multi-scalar analyses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Late Paleozoic transpression in Buenos Aires and northeast Patagonia ranges, Argentina

    NASA Astrophysics Data System (ADS)

    Rossello, E. A.; Massabie, A. C.; López-Gamundí, O. R.; Cobbold, P. R.; Gapais, D.

    1997-12-01

    Paleozoic sediments are present in three regions in eastern central Argentina: (1) the Sierras Australes of Buenos Aires, (2) Sierras Septentrionales of Buenos Aires and (3) Northeast Patagonia. All of these deposits share a common deformational imprint imparted by late Paleozoic Gondwanan deformation. Exposures of these rocks are scattered, variably deformed, and isolated by younger sediments deposited in basins related to the Mesozoic through Tertiary opening of the South Atlantic such as the offshore Colorado Basin. The Sierras Australes of Buenos Aires outcrops are the best preserved. They are mostly located along the Sierras Australes foldbelt, with minor outliers distributed in the adjacent Claromec-basin. The Tunas Formation (early-early late? Permian) is the uppermost unit of the Pillahuincó Group (late Carboniferous-Permian) and is crucial to the understanding of the tectono-sedimentary evolution of the region during the late Paleozoic. The underlying units of the Pillahuincó Group (Sauce Grande, Piedra Azul and Bonete Formations) exhibit a depositional and compositional history characterized by glaciomarine sedimentation and postglacial transgression. They are also characterized by rather uniform quartz-rich compositions indicative of a cratonic provenance from the La Plata craton to the NE. In contrast, the sandstone-rich Tunas Formation has low quartz contents, and abundant volcanic and metasedimentary fragments; paleocurrents are consistently from the SW. Glassrich tuffs are interbedded with sandstone in the upper half of the Tunas Formation. The age of the deformation in the Sierras Australes is Permian and early-middle Triassic. This is based on metamorphic events indicated by formation of illite at 282 ± 3 Ma, 273 ± 8 Ma, 265 ± 3 Ma, and 260 ± 3 Ma ( {K}/{Ar} illite) in the Silurian Curamalal Group. Evidence of syntectonic magmatism is provided by a radiometric date of 245 ± 12 Ma ( {K}/{Ar} hornblende) for the López Lecube Granite

  10. [Scientific production from public hospitals of the City of Buenos Aires, 2017].

    PubMed

    Ibarra, Mariano; Torrents, Milagros; Ossorio, María Fabiana; Ferrero, Fernando

    2018-01-01

    The number of publications in the scientific literature coming from an institution is an indicator of its scientific production. The scientific production of the hospitals of the Government of the City of Buenos Aires (GCBA) has been evaluated previously, but without discriminating how much of that production corresponded to other academic institutions settled there (University of Buenos Aires, UBA, National Council of Scientific Research and Techniques, CONICET). Our objective was to evaluate the publications included in PubMed that correspond to hospitals of the GCBA, describe their main characteristics, and discriminate the contribution of other academic institutions (UBA and CONICET). It is a cross-sectional study based on a PubMed search, using the name of each of the 34 GCBA hospitals, CONICET and UBA in the "affiliation" field. In total, 2727 publications from GCBA hospitals were identified (4.6% of Argentine publications); 73.9% in English, 78.9% in relation to humans, 37.2% in the last 5 years; 6.4% with high level of evidence (clinical trials and meta-analysis), and 28.4% including children. Compared to the national total, the GCBA publications include fewer works in English, more research in humans, more clinical trials and more research in children. Of the publications corresponding to hospitals of the GCBA, 90.4% did not share the affiliation with CONICET or with UBA. In conclusion, the GCBA hospitals generated 4.6% of the total Argentine publications in PubMed; and 90% of these was not shared with UBA or CONICET. Publications from GCBA institutions include more clinical trials and research in children.

  11. ["Medical Deputies": clinics and politics in the dispute for public resources in Buenos Aires (1906-1917)].

    PubMed

    Souza, P; Hurtado, D

    2008-01-01

    In June 1906, the conservative deputy and doctor Eliseo Cantón submitted in the Argentinian Parliament the project of a , which would take up four blocks, would be located in front of the Faculty of Medicine of the University of Buenos Aires and would be made up by 20 institutes with a capacity for 80 beds each. The dispute over this huge project, which lasted until 1917, placed in the middle of the scene, a group of "medical deputies" who used the political platform as a space to define the main aspects of the hospital system. The controversy went beyond the Parliament reaching the public sphere. The lavishness of the project on the eve of the Centenary public festivities or the opulence of a Buenos Aires which inspired to be like Paris were related, in a symbolic view, to the progress of local medicine and its aspirations to be included in the international medical arena. The analysed case helps understand how an essentially political controversy - which led to economical, ethical and cognitive discussions - intervened in the process of building up a socio-professional space of the hospital medical practice.

  12. [Severe depression and risk factors in Buenos Aires].

    PubMed

    Serfaty, E; Andrade, J; D'Aquila, H; Masautis, A E; Foglia, L

    1995-03-01

    A study on prevalence of depression and its risk factors in 18 year old males with residence in the city of Buenos Aires was performed in 1991 during a mass medical examination of aptitude for the Military Service. An anonyme, self administered questionnaire was given to 553 youngsters in a probability sample. From findings in that study it was deemed necessary a deepen analysis on severe depression and its possible associations with ideas of suicide. Prevalence at severe depression was 4.5% and strong association was found with sadness in depression was 4.5% and strong association was found with sadness in childhood (RR 12.73), boredom (RR 10.56), retiring (RR 8.28) and nervousness (RR 3.89) as well as drugs abuse by brothers (RR 3.48) and family conflicts (RR 2.43). Possibility of having ideas of suicide is thirty three times more when depression exists. The attributable risk of suicide due to severe depression is 75%. Keeping in mind this health problem in youngsters might help to establish collective and individual strategic measures toward prevention.

  13. [Air contamination in the Autonomous City of Buenos Aires: the current risk or future climate change, a false option].

    PubMed

    Abrutzky, Rosana; Dawidowski, Laura; Murgida, Ana; Natenzon, Claudia Eleonor

    2014-09-01

    Based on the theoretical framework of environmental risk, this article discusses the management of air quality in the Autonomous City of Buenos Aires in relation to current and potential impacts of toxic gases and global climate change on the health of the population. Information on historical and current management of the air was linked to the results of the South American Emissions, Megacities and Climate research project to assess danger, exposure, vulnerability and uncertainty as the dimensions of risk. By contextualizing public policies developed in recent decades on this subject, it was possible to identify emerging configurations of risk and uncertainties as accelerators of social vulnerability. On the one hand, the fact that there is a positive correlation between mortality, changes in temperature and air pollution was confirmed. On the other hand, it became clear that there is a disconnect between air quality management and health care management, while limitations were found in the proposed mitigation measures relating to emissions of greenhouse gases produced by fuel, revealing uncertainties regarding their efficacy.

  14. "Zafar," So Good: Middle-Class Students, School Habitus and Secondary Schooling in the City of Buenos Aires (Argentina)

    ERIC Educational Resources Information Center

    Meo, Analia Ines

    2011-01-01

    This article examines how students from the "loser" sections of the middle class dealt with the game of secondary schooling in a "good" state school in the city of Buenos Aires (Argentina). It engages with Bourdieu's theory of social practice and, in particular, with its concepts of game, habitus and cultural capital. It argues…

  15. Methodological and Ethical Dilemmas Encountered during Field Research of Family Violence Experienced by Adolescent Women in Buenos Aires

    ERIC Educational Resources Information Center

    Luxardo, Natalia; Colombo, Graciela; Iglesias, Gabriela

    2011-01-01

    The purpose of this article is to examine some obstacles and dilemmas related to methodological strategies and ethical considerations that arose during the fieldwork of research focused on family violence during the stages of pregnancy and childbirth in adolescent females in Buenos Aires during 2007. From this study, we are able to contribute some…

  16. Chronic urticaria in a health maintenance organization of Buenos Aires, Argentina - new data that increase global knowledge of this disease.

    PubMed

    Parisi, Claudio Alberto; Ritchie, Carla; Petriz, Natalia; Torres, Christian Morelo; Gimenez-Arnau, Ana

    2018-01-01

    In spite of the frequency of chronic urticaria, there are no epidemiological studies on its prevalence in Argentina. The objective of this study was to define the prevalence and epidemiological characteristics of chronic urticaria patients in Buenos Aires. The population studied were the members of the Italian Hospital Medical Care Program, a prepaid health maintenance organization located in the urban areas around the Autonomous City of Buenos Aires, Argentina. All patients with diagnosis of chronic urticaria members of the Italian Hospital Medical Care Program, and with at least 12 months of follow up were included in the study. All medical records obtained between January 1st, 2012 and December 31, 2014 were analyzed. The prevalence ratio for chronic urticaria per 100,000 population with 95% CI for December 31, 2014 was calculated. The prevalence rate for the entire population and then discriminated for adults and pediatric patients (less than 18 years old at diagnosis) was assessed. 158,926 members were analyzed. A total of 463 cases of chronic urticaria were identified on prevalence date (68 in pediatrics, 395 in adults), yielding a crude point prevalence ratio of 0.29% (CI 95% 0.26-0.31%). The observed prevalence of chronic urticaria in the adult population was 0.34 % (95% CI 0.31-0.38%), while in pediatrics it was 0.15 % (95% CI 0.11-0.20%). the main weakness is that the results were obtained from an HMO and therefore the possibility of selection bias. chronic urticaria is a global condition. Its prevalence in Buenos Aires is comparable with other countries.

  17. Glucose-6-phosphate dehydrogenase Buenos Aires: a novel de novo missense mutation associated with severe enzyme deficiency.

    PubMed

    Minucci, Angelo; Concolino, Paola; Vendittelli, Francesca; Giardina, Bruno; Zuppi, Cecilia; Capoluongo, Ettore

    2008-06-01

    : Glucose 6-phosphate dehydrogenase (G6PD) catalyzes the first committed steps in the pentose phosphate pathway: the generation of NADPH by this enzyme is essential for protection against oxidative stress. The human enzyme is in a dimer<-->tetramer equilibrium and its stability depends on NADP(+) concentration. Herein, we report a case of a symptomatic baby affected by severe deficiency of G6PD activity due to a novel de novo genetic mutation (g1465C>T) in the thirteenth exon of its gene. : Clinical, biochemical and genetic evaluations of the affected baby and his mother were performed. : We found the g1465C>T novel mutation, in the thirteenth exon of G6PD gene (named "G6PD Buenos Aires variant"). This g1465C>T mutation produce a P489S substitution at protein level. The P489S mutation was absent in his mother, suggesting that G6PD Buenos Aires resulted from a de novo mutation. : The absence of mosaicism in the baby's DNA (from saliva and blood samples) suggests that a de novo mutation event may occur in the very early stages in embryogenesis or in the mother's germ cell lines.

  18. [Comparison of the prevalence of molar incisor hypomineralization among children with different health care coverage in the cities of Buenos Aires (Argentina) and Montevideo (Uruguay)].

    PubMed

    López Jordi, María del Carmen; Cortese, Silvina G; Álvarez, Licet; Salveraglio, Inés; Ortolani, Andrea M; Biondi, Ana M

    2014-08-01

    The aim of this study was to compare the prevalence of molar incisor hypomineralization (MIH) among children with different health care coverage in Buenos Aires and Montevideo. An observational, cross-sectional and descriptive study was designed, considering children born from 1993-2003 who were seen in the Chairs of Comprehensive Children's Dentistry (Universidad de Buenos Aires) and of Pediatric Dentistry (Universidad de la República) and at five private dental offices between April and December 2010. Two groups were defined: A (Buenos Aires; n=1,090) and B (Montevideo; n=626). The clinical diagnosis was carried out with calibrated examiners (Kappa: 0.94) using the Mathu-Muju and Wright criteria. The prevalence of MIH was found to be 16.1% in A and 12.3% in B (p=0.03), with statistically significant differences between the public and private care sectors in both groups (A p=0.0008; B p=0.0004) and a positive correlation between MIH and year of birth (A p=0.001; B p=0.005). The results show that MIH is an emerging pathology and that MIH prevalence is related to year of birth and access to health care.

  19. Personalization and Competition in Elite Schools in Buenos Aires: School Strategies for the Production and Legitimization of Dominant Groups

    ERIC Educational Resources Information Center

    Ziegler, Sandra

    2017-01-01

    This article analyses the strategies found in two elite secondary institutions in Buenos Aires designed to legitimise the selection of students aspiring to become members of the elite. The first are personalization strategies where teachers and students work together with the aim of facilitating success in examinations. The second are strategies…

  20. Presentación del estudio "Links" de hombres que tienes sexo con hombres en Buenos Aires, Argentina.

    PubMed

    Carballo-Diéguez, Alex; Avila, María M; Balán, Iván C; Marone, Rubén; Pando, María A; Barreda, Victoria

    2011-03-01

    Estudios previos en Buenos Aires reportaron altas prevalencias de HIV entre HSH, con valores que oscilan entre 9 y 14% durante casi 10 años de continuo testeo. El objetivo principal de este estudio fue la evaluación de factores relacionados al comportamiento de alto riesgo para transmisión del HIV entre HSH entre los que se incluyen el conocimiento y factores emocionales, socioculturales y ambientales. Por otro lado se realizó la estimación de prevalencia e incidencia de HIV utilizando RDS (Respondent Driven Sampling), así como la presencia de otras infecciones de transmisión sexual. Por último se evaluaron los hábitos de testeo para HIV indagando que factores facilitan o impiden su realización. El estudio constó de dos fases, en primer lugar una fase cualitativa y posteriormente una fase cuantitativa con una duración total de 4 años y medio. Durante la fase cualitativa se realizaron 44 entrevistas individuales en profundidad, 8 grupos focales y 10 observaciones etnográficas (hoteles, baños públicos ("teteras"), cines pornográficos, fiestas privadas, dark rooms y discotecas). Durante la fase cuantitativa del estudio se realizó el reclutamiento de 500 participantes que provinieron de la Ciudad Autónoma de Buenos Aires, así como del Gran Buenos Aires. El reclutamiento se comenzó con 16 participantes llamados semillas. Se realizó el diagnóstico de infección por HIV, hepatitis B y C (HBV y HCV), Treponema pallidum, Virus Papiloma Humano (HPV) y Chlamidias. La colaboración establecida entre los grupos de trabajo enfocados en áreas diversas posibilitó el abordaje conjunto de nuevas estrategias de investigación antes no exploradas en nuestro país. Los resultados más relevantes de esta investigación serán progresivamente publicados en sucesivos números de Actualizaciones en SIDA.

  1. "Quien Sabe Mas Lucha Mejor": Adult Educators' Care of the Self Practices within Social Movements in Buenos Aires, Argentina

    ERIC Educational Resources Information Center

    O'Donnell, Jennifer Lee

    2014-01-01

    This article looks at popular adult educators' care of the self practices within social movements in Buenos Aires, Argentina. It answers the following questions: How is popular adult education practiced amongst educators in social movements? What can studying popular adult educators' care of the self practices offer the field of adult education?…

  2. Chronic urticaria in a health maintenance organization of Buenos Aires, Argentina - new data that increase global knowledge of this disease*

    PubMed Central

    Parisi, Claudio Alberto; Ritchie, Carla; Petriz, Natalia; Torres, Christian Morelo; Gimenez-Arnau, Ana

    2018-01-01

    Background In spite of the frequency of chronic urticaria, there are no epidemiological studies on its prevalence in Argentina. Objective The objective of this study was to define the prevalence and epidemiological characteristics of chronic urticaria patients in Buenos Aires. Methods The population studied were the members of the Italian Hospital Medical Care Program, a prepaid health maintenance organization located in the urban areas around the Autonomous City of Buenos Aires, Argentina. All patients with diagnosis of chronic urticaria members of the Italian Hospital Medical Care Program, and with at least 12 months of follow up were included in the study. All medical records obtained between January 1st, 2012 and December 31, 2014 were analyzed. The prevalence ratio for chronic urticaria per 100,000 population with 95% CI for December 31, 2014 was calculated. The prevalence rate for the entire population and then discriminated for adults and pediatric patients (less than 18 years old at diagnosis) was assessed. Results 158,926 members were analyzed. A total of 463 cases of chronic urticaria were identified on prevalence date (68 in pediatrics, 395 in adults), yielding a crude point prevalence ratio of 0.29% (CI 95% 0.26-0.31%). The observed prevalence of chronic urticaria in the adult population was 0.34 % (95% CI 0.31-0.38%), while in pediatrics it was 0.15 % (95% CI 0.11-0.20%). Study limitations the main weakness is that the results were obtained from an HMO and therefore the possibility of selection bias. Conclusions chronic urticaria is a global condition. Its prevalence in Buenos Aires is comparable with other countries. PMID:29641702

  3. Viral diagnostic criteria for Feline immunodeficiency virus and Feline leukemia virus infections in domestic cats from Buenos Aires, Argentina.

    PubMed

    Galdo Novo, Sabrina; Bucafusco, Danilo; Diaz, Leandro M; Bratanich, Ana Cristina

    A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Paradoxical Personality and Academic Achievement in College Students From Buenos Aires

    PubMed Central

    Freiberg Hoffmann, Agustín; Fernández Liporace, María Mercedes

    2015-01-01

    This paper presents a study on paradoxical personality, defined as a distinctive feature in creative persons, developed with 350 college students from Buenos Aires. Goals aimed at describing and analysing possible significant differences of paradoxical traits in students from diverse majors representing seven different fields of study, and examining the relationship between each bipolar trait and academic achievement. The sample was composed of 7 groups (n = 50 by group) representing fields of study typically offered in public universities, Biology, Computer Science, Engineering, Law, Nutrition, Psychology, and History of Art. Analyses by career provided descriptive information about students of these majors, concerning their paradoxical personality profiles. Correlational studies verified significant associations between academic achievement and most paradoxical traits in majors such as Computer Science, Nutrition and Psychology. Results are discussed regarding practical outcomes and teaching programs. PMID:27247680

  5. Presentación del estudio “Links” de hombres que tienes sexo con hombres en Buenos Aires, Argentina

    PubMed Central

    Carballo-Diéguez, Alex; Ávila, María M; Balán, Iván C.; Marone, Rubén; Pando, María A.; Barreda, Victoria

    2011-01-01

    Resumen Estudios previos en Buenos Aires reportaron altas prevalencias de HIV entre HSH, con valores que oscilan entre 9 y 14% durante casi 10 años de continuo testeo. El objetivo principal de este estudio fue la evaluación de factores relacionados al comportamiento de alto riesgo para transmisión del HIV entre HSH entre los que se incluyen el conocimiento y factores emocionales, socioculturales y ambientales. Por otro lado se realizó la estimación de prevalencia e incidencia de HIV utilizando RDS (Respondent Driven Sampling), así como la presencia de otras infecciones de transmisión sexual. Por último se evaluaron los hábitos de testeo para HIV indagando que factores facilitan o impiden su realización. El estudio constó de dos fases, en primer lugar una fase cualitativa y posteriormente una fase cuantitativa con una duración total de 4 años y medio. Durante la fase cualitativa se realizaron 44 entrevistas individuales en profundidad, 8 grupos focales y 10 observaciones etnográficas (hoteles, baños públicos (“teteras”), cines pornográficos, fiestas privadas, dark rooms y discotecas). Durante la fase cuantitativa del estudio se realizó el reclutamiento de 500 participantes que provinieron de la Ciudad Autónoma de Buenos Aires, así como del Gran Buenos Aires. El reclutamiento se comenzó con 16 participantes llamados semillas. Se realizó el diagnóstico de infección por HIV, hepatitis B y C (HBV y HCV), Treponema pallidum, Virus Papiloma Humano (HPV) y Chlamidias. La colaboración establecida entre los grupos de trabajo enfocados en áreas diversas posibilitó el abordaje conjunto de nuevas estrategias de investigación antes no exploradas en nuestro país. Los resultados más relevantes de esta investigación serán progresivamente publicados en sucesivos números de Actualizaciones en SIDA. PMID:25264397

  6. John Tweedie and Charles Darwin in Buenos Aires.

    PubMed

    Ollerton, Jeff; Chancellor, Gordon; van Wyhe, John

    2012-06-20

    The journey of exploration undertaken by Charles Darwin FRS during the voyage of HMS Beagle has a central place within the historical development of evolutionary theory and has been intensively studied. Despite this, new facts continue to emerge about some of the details of Darwin's activities. Drawing on recently published Darwin material and unpublished letters in the archives of the Royal Botanic Gardens, Kew, we document a hitherto unexamined link between Darwin and John Tweedie (1775-1862), a relatively obscure Scottish gardener turned South American plant collector. All of the available evidence points to a meeting between the two men in Buenos Aires in 1832. Tweedie provided Darwin with information about the geography of the Rio Paraná, including the locality of fossilized wood eroding from the river bank. It also seems likely that Tweedie supplied Darwin with seeds that he later shipped back to John Stevens Henslow in Cambridge. Although this brief meeting was at the time relatively unimportant to either man, echoes of that encounter have resonated with Tweedie's descendants to the present day and have formed the basis for a family story about a written correspondence between Darwin and Tweedie. Local information supplied to Darwin by residents such as Tweedie was clearly important and deserves further attention.

  7. Hydrogen Sulfide Emissions from Sow Farm Lagoons across Climates Zones.

    PubMed

    Grant, Richard H; Boehm, Matthew T; Lawrence, Alfred J; Heber, Albert J

    2013-11-01

    Hydrogen sulfide (HS) emissions were measured periodically over the course of 2 yr at three sow waste lagoons representing humid mesothermal (North Carolina, NC), humid microthermal (Indiana, IN), and semiarid (Oklahoma, OK) climates. Emissions were determined using a backward Lagrangian stochastic model in conjunction with line-sampled HS concentrations and measured turbulence. The median annual sow-specific (area-specific) lagoon emissions at the OK farm were approximately 1.6 g head [hd] d (5880 µg m s), whereas those at the IN and NC sow farms were 0.035 g hd d (130 µg m s), and 0.041 g hd d (260 µg m s), respectively. Hydrogen sulfide emissions generally increased with wind speed. The daily HS emissions from the OK lagoon were greatest during the first half of the year and decreased as the year progressed. Emissions were episodic at the NC and IN lagoons. The generally low emissions at the NC and IN lagoons were probably a result of significant populations of purple sulfur bacteria maintained in the humid mesothermal and humid microthermal climates. Most of the large HS emission events at the NC and IN lagoons appeared to be a result of either precipitation events or liquid pump-out events. The high emissions at the OK lagoon in a semiarid climate were largely a result of high wind speeds enhancing both lagoon and air boundary layer mixing. The climate (air temperature, winds, and precipitation) appeared to influence the HS emissions from lagoons. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  8. Talking to Strangers--A Sociolinguistic Experiment: Variation in Initial Dyadic Interactions between Spanish-Speakers in Early 21st Century Buenos Aires, Argentina

    ERIC Educational Resources Information Center

    Dziugis, Mary Ann

    2010-01-01

    What are the chances of a dyad of Spanish-speaking strangers using informal address in casual, initial interactions in Buenos Aires, Argentina, today? To discover the pattern(s) of contemporary address, the Principal Investigator (PI) conducted a sociolinguistic experiment focusing on strangers' initial interactions to minimize the influence of…

  9. Spatial analysis of the tuberculosis treatment dropout, Buenos Aires, Argentina

    PubMed Central

    Herrero, María Belén; Arrossi, Silvina; Ramos, Silvina; Braga, Jose Ueleres

    2015-01-01

    OBJECTIVE Identify spatial distribution patterns of the proportion of nonadherence to tuberculosis treatment and its associated factors. METHODS We conducted an ecological study based on secondary and primary data from municipalities of the metropolitan area of Buenos Aires, Argentina. An exploratory analysis of the characteristics of the area and the distributions of the cases included in the sample (proportion of nonadherence) was also carried out along with a multifactor analysis by linear regression. The variables related to the characteristics of the population, residences and families were analyzed. RESULTS Areas with higher proportion of the population without social security benefits (p = 0.007) and of households with unsatisfied basic needs had a higher risk of nonadherence (p = 0.032). In addition, the proportion of nonadherence was higher in areas with the highest proportion of households with no public transportation within 300 meters (p = 0.070). CONCLUSIONS We found a risk area for the nonadherence to treatment characterized by a population living in poverty, with precarious jobs and difficult access to public transportation. PMID:26270011

  10. Spatial analysis of the tuberculosis treatment dropout, Buenos Aires, Argentina.

    PubMed

    Herrero, María Belén; Arrossi, Silvina; Ramos, Silvina; Braga, Jose Ueleres

    2015-01-01

    OBJECTIVE Identify spatial distribution patterns of the proportion of nonadherence to tuberculosis treatment and its associated factors. METHODS We conducted an ecological study based on secondary and primary data from municipalities of the metropolitan area of Buenos Aires, Argentina. An exploratory analysis of the characteristics of the area and the distributions of the cases included in the sample (proportion of nonadherence) was also carried out along with a multifactor analysis by linear regression. The variables related to the characteristics of the population, residences and families were analyzed. RESULTS Areas with higher proportion of the population without social security benefits (p = 0.007) and of households with unsatisfied basic needs had a higher risk of nonadherence (p = 0.032). In addition, the proportion of nonadherence was higher in areas with the highest proportion of households with no public transportation within 300 meters (p = 0.070). CONCLUSIONS We found a risk area for the nonadherence to treatment characterized by a population living in poverty, with precarious jobs and difficult access to public transportation.

  11. Aerosol properties and meteorological conditions in the city of Buenos Aires, Argentina, during the resuspension of volcanic ash from the Puyehue-Cordón Caulle eruption

    NASA Astrophysics Data System (ADS)

    Graciela Ulke, Ana; Torres Brizuela, Marcela M.; Raga, Graciela B.; Baumgardner, Darrel

    2016-09-01

    The eruption in June 2011 of the Puyehue-Cordón Caulle Volcanic Complex in Chile impacted air traffic around the Southern Hemisphere for several months after the initial ash emissions. The ash deposited in vast areas of the Patagonian Steppe was subjected to the strong wind conditions prevalent during the austral winter and spring experiencing resuspension over various regions of Argentina. In this study we analyze the meteorological conditions that led to the episode of volcanic ash resuspension which impacted the city of Buenos Aires and resulted in the closure of the two main airports in Buenos Aires area (Ezeiza and Aeroparque) on 16 October 2011. A relevant result is that resuspended material (volcanic ash plus dust) imprints a distinguishable feature within the atmospheric thermodynamic vertical profiles. The thermodynamic soundings show the signature of "pulses of drying" in layers associated with the presence of hygroscopic ash in the atmosphere that has already been reported in similar episodes after volcanic eruptions in other parts of the world. This particular footprint can be used to detect the probable existence of volcanic ash layers. This study also illustrates the utility of ceilometers to detect not only cloud base at airports but also volcanic ash plumes at the boundary layer and up to 7 km altitude. Aerosol properties measured in the city during the resuspension episode indicate the presence of enhanced concentrations of aerosol particles in the boundary layer along with spectral signatures in the measurements at the Buenos Aires AERONET site typical of ash plus dust advected towards the city. The mandatory aviation reports from the National Weather Service about airborne and deposited volcanic ash at the airport near the measurement site (Aeroparque) correlate in time with the enhanced concentrations. The presence of the resuspended material was detected by the CALIOP lidar overpassing the region. Since the dynamics of ash resuspension and

  12. [Distribution of findings of scorpions in Buenos Aires city in the period 2001-2012 and their sanitary implications].

    PubMed

    Blanco, Guillermo; Laskowicz, Rodrigo D; Lanari, Laura C; Scarlato, Eduardo; Damin, Carlos; de Titto, Ernesto H; de Roodt, Adolfo R

    2016-02-01

    Scorpion stings and their associated mortality increased in the last years in Argentina, with a cumulative record of 73,617 cases and 30 deaths during the period 2001-2012, occurring almost all the deaths in pediatric patients. However, deaths due to severe envenoming by scorpion stings have not been recorded in Buenos Aires city and suburban regions, although the presence of scorpions in this city has been increasingly reported. We studied the temporal and geographical distribution of Tityus trivittatus findings in Buenos Aires city from the database of the Research and Development Area from the National Institute for Production of Biologics of the National Ministry of Health during the period 10/01/2001 to 31/12/2012 in order to correlate these findings with the distribution of health centers in the city. In this period 385 consults with identification of scorpions were recorded. Annual records showed a growing trend. Georeferenced data showed that findings appeared to increase in the surroundings of metro and train stations, mainly at the east of the city with expansion to the west. Although Toxicology services are geographically related to the zones with higher density of finding of scorpions, the accessibility to the centers with antivenom may hinder its application in the recommended time; some measures to avoid possible delays in the application of the treatment are suggested. Sociedad Argentina de Pediatría.

  13. The Moral Dimension of Class and Gender Identity-Making: Poverty and Aggression in a Secondary School in the City of Buenos Aires

    ERIC Educational Resources Information Center

    Meo, Analia Ines

    2011-01-01

    This paper presents some results of a qualitative study carried out in a secondary school in the city of Buenos Aires (Argentina). It examines how two students from poor families responded to, and viewed, aggression by peers at their school. This paper argues that the examination of students' narratives about aggression (based on classism and…

  14. Prediction of seasonal water-table fluctuations in La Pampa and Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Tanco, Raúl; Kruse, Eduardo

    2001-07-01

    The fluctuation of the water table east of La Pampa province and northwest of Buenos Aires province, Argentina, influences agricultural production in the region because it is closely related to the alternation of dry and wet periods. Sea-surface temperature (SST) anomalies have been used as predictors to forecast atmospheric variables in different regions of the world. The objective of this work is to present a simple model to forecast seasonal rainfall using SST distribution in the Pacific Ocean as a predictor. Once the relationship between precipitation and water-table fluctuations was established, a methodology for the prediction of water-table fluctuations was developed. A good agreement between observed and predicted water-table fluctuations was found when estimating water-table fluctuations in the summer and autumn seasons. Résumé. Les fluctuations de la nappe à l'est de la province de La Pampa et au nord-ouest de la province de Buenos Aires (Argentine) influence la production agricole de la région parce qu'elle est étroitement liée à l'alternance de saisons sèches et humides. Les anomalies de la température de surface de l'océan (SST) ont été utilisées comme prédicteurs pour prévoir les variables atmosphériques dans différentes régions du monde. L'objectif de ce travail est de présenter un modèle simple de prévision des précipitations saisonnières en utilisant comme prédicteur la distribution des SST dans l'Océan Pacifique. Une fois que la relation entre les fluctuations des précipitations et celles de la nappe a été établie, une méthodologie de prédiction des variations de la nappe a été mise au point. Un bon accord entre les variations de la nappe observées et celles prédites a été trouvé pour les estimations des variations de nappe en été et en automne. Resumen. La fluctuación del nivel freático al este de la provincia de La Pampa y al nordeste de la de Buenos Aires (Argentina) repercute en la producción agr

  15. Water sources, mixing and evaporation in the Akyatan lagoon, Turkey

    NASA Astrophysics Data System (ADS)

    Lécuyer, C.; Bodergat, A.-M.; Martineau, F.; Fourel, F.; Gürbüz, K.; Nazik, A.

    2012-12-01

    Akyatan lagoon, located southeast of Turkey along the Mediterranean coast, is a choked and hypersaline lagoon, and hosts a large and specific biodiversity including endangered sea turtles and migrating birds. Physicochemical properties of this lagoon were investigated by measuring temperature, salinity, and hydrogen and oxygen isotope ratios of its waters at a seasonal scale during years 2006 and 2007. Winter and spring seasons were dominated by mixing processes between freshwaters and Mediterranean seawater. The majority of spring season waters are formed by evapoconcentration of brackish water at moderate temperatures of 22 ± 2 °C. During summer, hypersaline waters result from evaporation of seawater and brackish waters formed during spring. Evaporation over the Akyatan lagoon reaches up to 76 wt% based on salinity measurements and operated with a dry (relative humidity of 0.15-0.20) and hot (44 ± 6 °C) air. These residual waters were characterized by the maximal seasonal isotopic enrichment in both deuterium and 18O relative to VSMOW. During autumn, most lagoonal waters became hypersaline and were formed by evaporation of waters that had isotopic compositions and salinities close to that of seawater. These autumnal hypersaline waters result from an air humidity close to 0.45 and an atmospheric temperature of evaporation of 35 ± 5 °C, which are responsible for up to 71 wt% of evaporation, with restricted isotopic enrichments relative to VSMOW. During the warm seasons, the combination of air humidity, wind velocity and temperature were responsible for a large kinetic component in the total isotopic fractionation between water liquid and water vapour.

  16. Reading for All; Proceedings of the IRA (International Reading Association) World Congress on Reading (4th, Buenos Aires, Argentina, August 3-5, 1972).

    ERIC Educational Resources Information Center

    Karlin, Robert, Ed.

    This book contains papers presented at the Fourth International Reading Association World Congress on Reading in Buenos Aires, Argentina, in August 1972. The contents of the book are divided into three parts: "Literacy and Literature" includes papers on libraries, books, and reading by Jorge Borges, the future of reading by Theodore Harris, the…

  17. Acute exposure to Buenos Aires air particles (UAP-BA) induces local and systemic inflammatory response in middle-aged mice: A time course study.

    PubMed

    Orona, Nadia S; Ferraro, Sebastián A; Astort, Francisco; Morales, Celina; Brites, Fernando; Boero, Laura; Tiscornia, Gisela; Maglione, Guillermo A; Saldiva, Paulo H N; Yakisich, Sebastian; Tasat, Deborah R

    2016-01-01

    Exposure to air particulate matter (PM) is associated with increased cardiovascular morbimortality. However, PM doesn't affect equally to all people, being the old cohort the most susceptible and studied. We hypothesized that another specific life phase, the middle-aged subpopulation, may be negatively affected. Therefore, the aim of this study was to analyze in vivo the acute biological impact of two environmental particles, Urban Air Particles from Buenos Aires and Residual Oil Fly Ash, on the cardiorespiratory system of middle-aged mice, evaluating oxidative metabolism and inflammation. Both PM provoked a local and systemic inflammatory response, leading to a reduced alveolar area in the lung, an epicard inflammation in the heart, an increment of IL-6, and a reduction on PON 1 activity in serum of middle-aged animals. The positive correlation of local parameters with systemic markers of oxidative stress and inflammation could be responsible for associations of cardiovascular morbimortality in this subpopulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Middle and late holocene micromammal pathologies from Cueva Tixi (Tandilia Range, Buenos Aires Province, Argentina).

    PubMed

    Luna, Leandro; Aranda, Claudia; Quintana, Carlos

    2017-09-01

    Paleopathology in bones of very small mammals has rarely been studied. Different types of osseous lesions of mammals weighing under 0.2kg, recovered from the Holocene strata of Cueva Tixi archaeological and paleontological site (Tandilia range, province of Buenos Aires, Argentina), are described and discussed in this report. Several types of trauma, entheseal changes, degenerative joint diseases, and probable osteomyelitis were identified. The lesions were chronic, indicating that the animals were able to survive a period of convalescence, although in many cases the decreased capacity for locomotion likely was significant. These pathological findings open research avenues for very small mammals that usually are not considered in archaeological disease studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Doing gender in a toxic world. Women and freebase cocaine in the city of Buenos Aires (Argentina).

    PubMed

    Romo-Avilés, Nuria; Camarotti, Ana Clara; Tarragona, Alicia; Touris, Cecilia

    2015-04-01

    Consumption of freebase cocaine in Argentina has been investigated among males but not females. This qualitative study focuses on the complexity of relationships between gender identity and the use of drugs, investigating freebase cocaine as an example in the Metropolitan Area of Buenos Aires, Argentina. In-depth interviews were conducted with female consumers in 2010. The results reveal the different ways in which female identity is constructed in the context of social vulnerability. We identify ways of doing gender and feeling like a woman in a man's world that are associated with a higher risk of violence and exclusion for being female.

  20. Reconstruction of historic sea ice conditions in a sub-Arctic lagoon

    USGS Publications Warehouse

    Petrich, Chris; Tivy, Adrienne C.; Ward, David H.

    2014-01-01

    Historical sea ice conditions were reconstructed for Izembek Lagoon, Bering Sea, Alaska. This lagoon is a crucial staging area during migration for numerous species of avian migrants and a major eelgrass (Zostera marina) area important to a variety of marine and terrestrial organisms, especially Pacific Flyway black brant geese (Branta bernicla nigricans). Ice cover is a common feature of the lagoon in winter, but appears to be declining, which has implications for eelgrass distribution and abundance, and its use by wildlife. We evaluated ice conditions from a model based on degree days, calibrated to satellite observations, to estimate distribution and long-term trends in ice conditions in Izembek Lagoon. Model results compared favorably with ground observations and 26 years of satellite data, allowing ice conditions to be reconstructed back to 1943. Specifically, periods of significant (limited access to eelgrass areas) and severe (almost complete ice coverage of the lagoon) ice conditions could be identified. The number of days of severe ice within a single season ranged from 0 (e.g., 2001) to ≥ 67 (e.g., 2000). We detected a slight long-term negative trend in ice conditions, superimposed on high inter-annual variability in seasonal aggregate ice conditions. Based on reconstructed ice conditions, the seasonally cumulative number of significant or severe ice days correlated linearly with mean air temperature from January until March. Further, air temperature at Izembek Lagoon was correlated with wind direction, suggesting that ice conditions in Izembek Lagoon were associated with synoptic-scale weather patterns. Methods employed in this analysis may be transferable to other coastal locations in the Arctic.

  1. Fumigating the Hygienic Model City: Bubonic Plague and the Sulfurozador in Early-Twentieth-Century Buenos Aires.

    PubMed

    Engelmann, Lukas

    2018-07-01

    The 1899/1900 arrival of bubonic plague in Argentina had thrown the model status of Buenos Aires as a hygienic city into crisis. Where the idea of foreign threats and imported epidemics had dominated the thinking of Argentina's sanitarians at that time, plague renewed concerns about hidden threats within the fabric of the capital's dense environment; concerns that led to new sanitary measures and unprecedented rat-campaigns supported by the large-scale application of sulphur dioxide. The article tells the story of early twentieth-century urban sanitation in Buenos Aires through the lens of a new industrial disinfection apparatus. The Aparato Marot, also known as Sulfurozador was acquired and integrated in the capital's sanitary administration by the epidemiologist José Penna in 1906 to materialise two key lessons learned from plague. First, the machine was supposed to translate the successful disinfection practices of global maritime sanitation into urban epidemic control in Argentina. Second, the machine's design enabled public health authorities to reinvigorate a traditional hygienic concern for the entirety of the city's terrain. While the Sulfurozador offered effective destruction of rats, it promised also a comprehensive - and utopian - disinfection of the whole city, freeing it from all imaginable pathogens, insects as well as rodents. In 1910, the successful introduction of the Sulfurozador encouraged Argentina's medico-political elite to introduce a new principle of 'general prophylaxis'. This article places the apparatus as a technological modernisation of traditional sanitary practices in the bacteriological age, which preserved the urban environment - 'el terreno' - as a principal site of intervention. Thus, the Sulfurozador allowed the 'higienistas' to sustain a long-standing utopian vision of all-encompassing social, bodily and political hygiene into the twentieth century.

  2. "We talk of AIDS because we love life": a stakeholder assessment of HIV/AIDS organizations in Buenos Aires, Argentina.

    PubMed

    Spaulding, Alicen B; Brieger, William R

    This stakeholder assessment of HIV/AIDS service providing institutions in Argentina offers insights into the HIV/AIDS crisis in Spanish-speaking Latin America from an institutional level and makes recommendations for strengthening the work and functioning of these institutions. This stakeholder assessment was conducted to determine how HIV/AIDS prevention and management in Argentina affects and is affected by relevant HIV/AIDS institutions. Semi-structured qualitative interviews were conducted with 13 key leaders of organizations working in HIV/AIDS prevention in Buenos Aires including non-governmental, governmental, and academic institutions. Analyses of interviewee comments are presented according to four major themes: network connections, program resources, perceptions of success, and challenges. Key findings include the need for strengthening formal networks, increasing the involvement of other non-AIDS related social institutions in promoting HIV prevention, finding more sustainable funding options, working more effectively with the public sector to create policies and regulations favorable to the HIV/AIDS field, and addressing the lack of perceived susceptibility to HIV/AIDS in Argentine culture. From leaders' comments, recommendations are made for strengthening the HIV/AIDS network among key institutions including adapting the UNAIDS "Three Ones" principal to create one crosssector office responsible for coordinating HIV/AIDS work, formalizing agreements with institutions outside of Buenos Aires, increasing the role of schools in HIV/AIDS awareness, and designing programs that address lack of perceived susceptibility to HIV/AIDS among Argentines.

  3. A two-stage epidemiological study of eating disorders and muscle dysmorphia in male university students in Buenos Aires.

    PubMed

    Compte, Emilio J; Sepulveda, Ana R; Torrente, Fernando

    2015-12-01

    Studies using traditional screening instruments tend to report a lower prevalence of eating disorders (EDs) in men than is observed in women. It is therefore unclear whether such instruments are valid for the assessment of ED in males. Lack of a formal diagnostic definition of muscle dysmorphia syndrome (MD) makes it difficult to identify men at risk. The study aimed to assess the prevalence of ED and MD in male university students of Buenos Aires. A cross-sectional, two-stage, representative survey was of 472 male students from six different schools in Buenos Aires, mostly aged between 18 and 28 years. The first stage involved administration of self-report questionnaires (Eating Attitude Test-26; scores ≥15 indicate "at risk" status). In Stage 2 students at risk of developing EDs were evaluated with a clinical interview, the Eating Disorder Examination (EDE; 12th edition). Two control students were interviewed for every at risk student. The prevalence of EDs among university male students was 1.9% (n = 9). All participants with an ED presented with illness classified as eating disorder not otherwise specified (EDNOS). Using the Drive for Muscularity Scale (DMS) with a 52-point threshold we identified possible MD in 6.99% (n = 33) of the sample. The prevalence of ED detected in this study is comparable with previous findings in male populations, and below that observed in female populations. However, the prevalence of possible cases of MD resembles the total rate of EDs in women. Characteristics associated with EDs and MD in men are also discussed. © 2015 Wiley Periodicals, Inc.

  4. Sea level oscillations in coastal waters of the Buenos Aires province, Argentina

    NASA Astrophysics Data System (ADS)

    Dragani, W. C.; Mazio, C. A.; Nuñez, M. N.

    2002-03-01

    Sea level oscillations, with periods ranging from a few minutes to almost 2 h, have been observed at various tide stations located on the coast of Buenos Aires. Simultaneous records of sea level elevation measured in Mar de Ajó, Pinamar and Mar del Plata during 1982 have been spectrally analyzed. Significant spectral energy has been detected between 0.85 and 4.69 cycles per hour (cph) and the most energetic peaks have frequencies between 1.17 and 1.49 cph. Spectra, coherence, and phase difference have been analyzed for the most energetic event of the year. During that event, the most intensive spectral peak is at 1.17 cph for Mar de Ajó and Pinamar, and at 1.49 cph for Mar del Plata. Simultaneous total energy peaks at Mar de Ajó, Pinamar and Mar del Plata, and the coherence function estimated between Mar de Ajó and Pinamar suggests that sea level oscillations could be a regional phenomenon. The analyzed data suggest that sea level oscillations could be forced by atmospheric gravity waves associated with frontal passages.

  5. [Recent history: 12th International Conference on Cancer, Buenos Aires, Argentina, 1978].

    PubMed

    Spinelli, Hugo

    2014-04-01

    Using the approaches of history of the present, this article recovers the discussions surrounding the 12th International Conference on Cancer carried out in Buenos Aires in 1978, in reaction to which Georges Périès organized a "counter-conference" in Paris. In order to understand this discussion, the political situation of the time is described, as is the state of human rights at the time in Argentina, the role of the media - in particular the newspapers La Nación and Clarín and the magazine Gente - and the institutional position adopted by the National Academy of Medicine, as expressed in a letter sent to the presidents of the primary scientific societies of the world. The letter is reprinted in this text as a documentary source, taken from Memoria: Año 1978 (Presidencia de Dr. José E. Rivarola) [Acta: Year 1978 (Presidency of Dr. José E. Rivarola)]. The framework of the discussion makes reference to science's social policy versus science's supposed neutrality and the role of scientific societies.

  6. [Historical notes on Infectious Diseases Hospital Francisco Javier Muñiz in Buenos Aires, Argentina].

    PubMed

    Laval, Enrique

    2012-08-01

    The Infectious Diseases Hospital Francisco Javier Muñiz, Buenos Aires, Argentina, is the oldest in Latin America. It is over 100 years old and has a history worthy of pride. It became known as "Hospital of the pests" and was preceded by the old House of Insulation, which served as a quarantine station during epidemics of cholera, yellow fever and smallpox. The new House of Insulation, built in the neighborhood of Parque Patricios ("Barracks Hospital"), was renamed in 1904 in memory of Francisco Javier Muñiz, a former military doctor, naturalist and paleontologist. Its technical name is "Porteño Care Centre and National Reference Regional Infectious-Contagious Disease". It receives numerous national and foreign undergraduate and postgraduate students in its Departments of Infectious Diseases and Respiratory Diseases.

  7. Prosodic Transfer in Learner and Contact Varieties: Speech Rhythm and Intonation of Buenos Aires Spanish and L2 Castilian Spanish Produced by Italian Native Speakers

    ERIC Educational Resources Information Center

    Gabriel, Christoph; Kireva, Elena

    2014-01-01

    A remarkable example of Spanish-Italian contact is the Spanish variety spoken in Buenos Aires (Porteño), which is said to be prosodically "Italianized" due to migration-induced contact. The change in Porteño prosody has been interpreted as a result of transfer from the first language (L1) that occurred when Italian immigrants learned…

  8. Functional Foods and Nutraceuticals in a Market of Bolivian Immigrants in Buenos Aires (Argentina)

    PubMed Central

    Pochettino, María Lelia; Puentes, Jeremías P.; Buet Costantino, Fernando; Arenas, Patricia M.; Ulibarri, Emilio A.; Hurrell, Julio A.

    2012-01-01

    This paper presents the results of a research in urban ethnobotany, conducted in a market of Bolivian immigrants in the neighborhood of Liniers, Ciudad Autónoma de Buenos Aires (Argentina). Functional foods and nutraceuticals belonging to 50 species of 18 families, its products, and uses were recorded. Some products are exclusive from the Bolivian community; others are frequent within the community, but they are also available in the general commercial circuit; they are introduced into it, generally, through shops called dietéticas (“health-food stores”), where products associated with the maintenance of health are sold. On this basis, the traditional and nontraditional components of the urban botanical knowledge were evaluated as well as its dynamics in relation to the diffusion of the products. Both the framework and methodological design are innovative for the studies of the urban botanical knowledge and the traditional markets in metropolitan areas. PMID:22203866

  9. Assessment of the possible drought impact on farm production in the SE of the province of Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Hartmann, Tomas; Di Bella, Carlos; Oricchio, Patricio

    The extended drought situation in the southeast of Buenos Aires during the second half of year 2000 caused the government to invoke emergency laws. This action allowed farmers in the area to receive waivers for taxes and loans. The emergency laws remained in force during 2001, without further verification of environmental conditions for agriculture. Developing an assessment of the actual drought situation was relevant for taxing and national credit institutions. An assessment was performed of the actual drought situation of farms during the spring of 2001 in seven counties in Buenos Aires Province area. The assessment was done by comparing vegetation index values (NDVI)—as measured from NOAA-AVHRR satellite data—of September 2001 against NDVI time series values from previous years. Five categories were established to describe the relationship between the present index and the average of the time series. Farms within the area covered by the study were assigned to the appropriate category using GIS tools. It was confirmed that most of the area had NDVI values that were similar to the average values, or even higher. It was found that there were subareas where the vegetation index had decreased. For those cases, LANDSAT TM images of the area of September and October of 2001 were used for a detailed inspection. The study included rainfall data as well, confirming a normal regional situation. Both low and high-resolution satellite images were found to be useful tools for obtaining fast, economic, objective and conclusive results about the production capability of individual farms as well as the region as a whole.

  10. [An AIDS-related cognitive map in a sample of drug abusers in Buenos Aires City].

    PubMed

    Kornblit, A L; Bilyk, A

    1990-01-01

    This paper is an approach to AIDS as a topic among a drug abusers sample of the city of Buenos Aires. Research was carried out on the basis of a qualitative methodology. In an attempt at surveying opinions and attitudes of such a sample as regards AIDS (i.e. subjects' cognitive map), 21 drug abusers from three different rehabilitation programs operating in the B.A. area were interviewed. On the basis of the research performed, the authors elaborate communication strategies among drug abusers that would be helpful for authorities engaged in AIDS prevention to adopt. To boost a strategy likely to break up the AIDS-drug association existing in the mind of many an abuser would be highly advisable so that a separation be settled between both representations, thus giving drug abusers a higher motivation for self-care practice.

  11. Eddy Covariance Measurements of Methane Emissions from a Dairy Farm Waste Lagoon

    NASA Astrophysics Data System (ADS)

    Sokol, A. B.; Lauvaux, T.; Richardson, S.; Hlywiak, J.; Davis, K. J.; Hristov, A. N.

    2016-12-01

    Livestock manure management in dairy operations is a known source of methane (CH4), a potent greenhouse gas. Anaerobic waste lagoons are a common manure management technique; thus, their associated CH4 emissions are relevant to national greenhouse gas inventories and local air quality. Our objective was to characterize the variability of summertime CH4 emissions from a lagoon at a dairy facility in central Pennsylvania. Continuous flux measurements were taken over two weeks in July using the eddy covariance method, which uses high-frequency gas concentration and three-dimensional wind speed measurements to calculate turbulent fluxes from a source area. After data filtration based on turbulence characteristics and source area, the average CH4 flux density from the lagoon was estimated to be 99 μmol m-2 s-1. This implies daily lagoon emissions of 881 kg CH4, corresponding to an average emission rate of 340 g CH4 per cow per day. We observed no apparent relationship between emissions and air temperature or relative humidity, though an extended measurement period is needed to better quantify the relationship that is expected to exist between air and/or slurry temperature and CH4 flux. Our measured per-area emission rate is toward the high end of the range of estimates found in the literature. These results contribute to greenhouse gas inventory development and could have important implications for emission mitigation strategies.

  12. Ecotoxicological and Genotoxic Evaluation of Buenos Aires City (Argentina) Hospital Wastewater

    PubMed Central

    Juárez, Ángela Beatriz; Dragani, Valeria; Saenz, Magalí Elizabeth; Moretton, Juan

    2014-01-01

    Hospital wastewater (HWW) constitutes a potential risk to the ecosystems and human health due to the presence of toxic and genotoxic chemical compounds. In the present work we investigated toxicity and genotoxicity of wastewaters from the public hospital of Buenos Aires (Argentina). The effluent from the sewage treatment plant (STP) serving around 10 million inhabitants was also evaluated. The study was carried out between April and September 2012. Toxicity and genotoxicity assessment was performed using the green algae Pseudokirchneriella subcapitata and the Allium cepa test, respectively. Toxicity assay showed that 55% of the samples were toxic to the algae (%I of growth between 23.9 and 54.8). The A. cepa test showed that 40% of the samples were genotoxic. The analysis of chromosome aberrations (CA) and micronucleus (MN) showed no significant differences between days and significant differences between months. The sample from the STP was not genotoxic to A. cepa but toxic to the algae (%I = 41%), showing that sewage treatment was not totally effective. This study highlights the need for environmental control programs and the establishment of advanced and effective effluent treatment plants in the hospitals, which are merely dumping the wastewaters in the municipal sewerage system. PMID:25214834

  13. Concentrations and elemental composition of particulate matter in the Buenos Aires underground system

    NASA Astrophysics Data System (ADS)

    Murruni, L. G.; Solanes, V.; Debray, M.; Kreiner, A. J.; Davidson, J.; Davidson, M.; Vázquez, M.; Ozafrán, M.

    Total suspended particulate (TSP) samples have been collected at six stations in the C and B lines of the Buenos Aires underground system and, almost simultaneously, at six ground level sites outside and nearby the corresponding underground stations, in the Oct 2005/Oct 2006 period. All these samples were analyzed for mass and elemental Fe, Cu, and Zn concentrations by using the Particle Induced X-ray Emission (PIXE) technique. Mostly, TSP concentrations were found to be between 152 μg m -3 (25% percentile) and 270 μg m -3 (75% percentile) in the platform of the stations, while those in outside ambient air oscillated from 55 μg m -3 (25% percentile) to 137 μg m -3 (75% percentile). Moreover, experimental results indicate that TSP levels are comparable to those measured for other underground systems worldwide. Statistical results demonstrate that subway TSP levels are about 3 times larger on average than those for urban ambient air. The TSP levels inside stations and outdoors are poorly correlated, indicating that TSP levels in the metro system are mainly influenced by internal sources. Regarding metal concentrations, the most enriched element in TSP samples was Fe, the levels of which ranged from 36 (25% percentile) to 86 μg m -3 (75% percentile) in Line C stations, while in Line B ones they varied between 8 μg m -3 (25% percentile) and 46 μg m -3 (75% percentile). As a comparison, Fe concentrations in ambient air oscillated between 0.7 μg m -3 (25% percentile) and 1.2 μg m -3 (75% percentile). Other enriched elements include Cu and Zn. With regard to their sources, Fe and Cu have been related to processes taking place inside the subway system, while Zn has been associated with outdoor vehicular traffic. Additionally, concerns about possible health implications based on comparisons to various indoor air quality limits and available toxicological information are discussed.

  14. Simulation of regional-scale groundwater flow in the Azul River basin, Buenos Aires Province, Argentina

    NASA Astrophysics Data System (ADS)

    Varni, Marcelo R.; Usunoff, Eduardo J.

    A three-dimensional modular model (MODFLOW) was used to simulate groundwater flow in the Azul River basin, Buenos Aires Province, Argentina, in order to assess the correctness of the conceptual model of the hydrogeological system. Simulated heads satisfactorily match observed heads in the regional water-table aquifer. Model results indicate that: (1) groundwater recharge is not uniform throughout the region but is best represented by three recharge rates, decreasing downgradient, similar to the distribution of soils and geomorphological characteristics; and (2) evapotranspiration rates are larger than previous estimates, which were made by using the Thornthwaite-Mather method. Evapotranspiration rates estimated by MODFLOW agree with results of independent studies of the region. Model results closely match historical surface-flow records, thereby suggesting that the model description of the aquifer-river relationship is correct. Résumé Un modèle modulaire tridimensionnel (MODFLOW) a été utilisé pour simuler les écoulements souterrains dans le bassin de la rivière Azul (Province de Buenos Aires, Argentine), dans le but d'évaluer la justesse du modèle conceptuel du système hydrogéologique. La piézométrie simulée s'ajuste de façon satisfaisante à celle observée pour l'ensemble de la nappe. Les résultats du modèle indiquent que: (1) la recharge de la nappe n'est pas uniforme sur toute la région, mais qu'elle est mieux approchée par trois valeurs différentes, décroissant vers l'aval-gradient, en suivant la même distribution que les sols et les caractéristiques géomorphologiques et (2) l'évapotranspiration est nettement plus importante que prévu initialement à partir de la méthode de Thornthwaite-Mather. Les valeurs d'évapotranspiration fournies par MODFLOW concordent bien avec les résultats d'autres études portant sur la région. Les résultats du modèle reproduisent convenablement les chroniques de débit des écoulements de surface

  15. 13. Sewage treatment lagoon, drainage control at center left, looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Sewage treatment lagoon, drainage control at center left, looking south - Ellsworth Air Force Base, Delta Flight, Launch Control Facility, County Road CS23A, North of Exit 127, Interior, Jackson County, SD

  16. Comparative oceanography of coastal lagoons

    NASA Technical Reports Server (NTRS)

    Kjerfve, Bjorn

    1986-01-01

    The hypothesis that physical lagoon characteristics and variability depend on the channel connecting the lagoon to the adjacent coastal ocean is evaluated. The geographical, hydrological, and oceanographic characteristics of 10 lagoon systems are described and analyzed; these oceanographic features are utilized to classify the lagoon systems. Choked lagoons (Laguna Joyuda, Coorong, Lake St.Lucia, Gippsland Lakes, Lake Songkla/Thale Luang/Thale Noi, and Lagoa dos Patos) are prevalent on coasts with high wave energy and low tidal range; restricted lagoons (Lake Pontchartrain and Laguna de Terminos) are located on low/medium wave energy coasts with a low tidal range; and leaky lagoons (Mississippi Sound and Belize Lagoon/Chetumal Bay) are connected to the ocean by wide tidal passes that transmit oceanic effects into the lagoon with a minimum of resistance. The data support the hypothesis that the nature of the connecting channel controls system functions.

  17. Incidence rate of amyloidosis in patients from a medical care program in Buenos Aires, Argentina: a prospective cohort.

    PubMed

    Aguirre, María Adela; Boietti, Bruno Rafael; Nucifora, Elsa; Sorroche, Patricia Beatriz; González Bernaldo de Quirós, Fernán; Giunta, Diego Hernan; Posadas-Martínez, María Lourdes

    2016-09-01

    There are limited data concerning the incidence density (ID) of ATTRwt, AL and AA amyloidosis in the Argentinean population. Our aim was to estimate the ID of ATTRwt, AL and AA amyloidosis at the Hospital Italiano Medical Care Program in Buenos Aires, Argentina. Population was all members of a hospital-based health maintenance organization who were affiliated since January 2006 to December 2014. Each person was followed contributing time at risk since January 2006 or enrollment date to the final date. Incident cases of amyloidosis were captured from the institutional registry of amyloidosis. Incidence rate was calculated with 95% confidence intervals. During the nine-year study period, there were 15 patients with ATTRwt, 12 with AL and 2 with AA amyloidosis for 1 105 152 person-years of follow-up. The crude ID of ATTRwt amyloidosis was 13.5 (95%CI 8.1-22.4), that of AL amyloidosis 11 (95%CI: 6-19) and that of AA amyloidosis 1.8 (95%CI: 0.5-7.2) per 1 000 000 person-years. The highest ID was found in men (31.7 for ATTRwt, 15.9 for AL and 2.27 for AA amyloidosis per 1 000 000 person-years). The ID adjusted to the population of the city of Buenos Aires was 6.46 (95%CI: 3.17-9.74) for ATTRwt, 6.13 (95%CI: 2.57-9.7) for AL and 1.21 (95%CI: 0.56 to 2.99) for AA amyloidosis. This is the first paper to report the incidence density of ATTRwt, AL and AA amyloidosis in Latin America. Our results are consistent with other studies from other regions. Although systemic amyloidosis is a rare disease, it is a major health problem because of its morbi-mortality.

  18. Impact of wildfire smoke in Buenos Aires, Argentina, on ocular surface.

    PubMed

    Berra, Martin; Galperín, Gustavo; Dawidowski, Laura; Tau, Julia; Márquez, Isabel; Berra, Alejandro

    2015-01-01

    To evaluate the acute impact of the wildfire smoke episode in 2008 on the ocular surface of subjects living in the Metropolitan Area of Buenos Aires (MABA). A total of 86 subjects were evaluated: Group 1 comprised patients from a public ophthalmology hospital (N=35) and Group 2 comprised healthy volunteers (N=51). All subjects answered a questionnaire on ocular symptoms and underwent ophthalmologic examination [bulbar conjunctival hyperemia, corneal fluorescein staining, rose bengal vital staining, tear break-up time (TBUT), Schirmer I test, tear lysozyme, and impression cytology] during and after the acute episode. Concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), and particulate matter (PM) were measured before, during, and after the acute episode. Both groups showed a statically significant increase in ocular symptoms and bulbar conjunctival hyperemia and a statically significant decrease in tear break-up time during the acute episode. Group 1 showed more severe symptoms and a statistically significant increase in fluorescein and rose bengal staining intensities during the acute episode. We found a significant negative correlation between ocular symptoms and tear break-up time. During the episode, the levels of CO, NO2, and particulate matter in MABA were four times higher than the usual average levels for the same period in 2007 and 2009. Increased air pollution from the burning of biomass is associated with a decrease in the stability of the tear film (TBUT), generating areas of ocular surface exposure that may be the cause of the increased feeling of irritation. Group 1 was more affected by not having a healthy ocular surface, and thus consulted an ophthalmologist. Cytological changes in the conjunctiva were not observed, which could be due to the short duration of the episode.

  19. Improved water quality and reduction of odorous compounds in anaerobic lagoon columns receiving pre-treated pig wastewater

    USDA-ARS?s Scientific Manuscript database

    Large volumes of wastewater from confined pig production are stored in anaerobic lagoons. Control methods are needed to reduce air pollution by foul odors released from these lagoons. In a pilot-scale experiment, we evaluated the effect of pig wastewater pre-treatment on reducing the concentration o...

  20. [Mycotrophic capacity and efficiency of microbial consortia of arbuscular mycorrhizal fungi native of soils from Buenos Aires province under contrasting management].

    PubMed

    Thougnon Islas, Andrea J; Eyherabide, Mercedes; Echeverría, Hernán E; Sainz Rozas, Hernán R; Covacevich, Fernanda

    2014-01-01

    We characterized the infective and sporulation capacities of microbial consortia of arbuscular mycorrhizal fungi (AMF) native of Buenos Aires province (Argentina) and determined if some soil characteristics and mycorrhizal parameters could allow to select potentially beneficial inocula. Soil samples were selected from seven locations in Buenos Aires province all under agricultural (A) and pristine (P) conditions. The AMF were multiplied and mycorrhizal root colonization of trap plants was observed at 10 weeks of growth. Spore number in field was low; however, after multiplication spore density accounted for 80-1175 spores per 100g of soil. The principal component analysis showed that the P and Fe soil contents are the main modulators of infectivity and sporulation capacity. The mycorrhizal potential was determined in three locations, being high in Pristine Lobería and Agricultural Trenque Lauquen and low in Junín. Agricultural Lobería (AL) and Pristine Lobería (PL) inocula were selected and their efficiency was evaluated under controlled conditions. Even though shoot dry matter increases after inoculation was not significant (p>0.05) mycorrhizal response was greater than 40% for tomato and 25% for corn, particularly after inoculation with inocula from the agricultural management. These results could be associated to the incipient development of mycorrhizae in both species. Additional research should be conducted to further develop our findings in order to determine the factors involved in the selection of efficient inocula. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  1. Occurrence and seasonal distribution of polycyclic aromatic hydrocarbons and legacy and current-use pesticides in air from a Mediterranean coastal lagoon (Mar Menor, SE Spain).

    PubMed

    Carratalá, A; Moreno-González, R; León, V M

    2017-01-01

    The occurrence and seasonal distribution of polycyclic aromatic hydrocarbons (PAHs) and legacy and current-use pesticides (CUPs) in air were characterized around the Mar Menor lagoon using both active and passive sampling devices. The seasonal distribution of these pollutants was determined at 6 points using passive samplers. Passive sampler sampling rates were estimated for all detected analytes using an active sampler, considering preferentially winter data, due to probable losses in active sampling during summer (high temperatures and solar irradiation). The presence of 28 compounds (14 CUPs, 11 PAHs and 3 organochlorinated pesticides) were detected in air by polyurethane passive sampling. The most commonly detected contaminants (>95% of samples) in air were chlorpyrifos, chlorpyrifos-methyl and phenanthrene. The maximum concentrations corresponded to phenanthrene (6000 pg m -3 ) and chlorpyrifos (4900 pg m -3 ). The distribution of contaminants was spatially and seasonally heterogeneous. The highest concentrations of PAHs were found close to the airport, while the highest concentrations of pesticides were found in the influence area of agricultural fields (western stations). PAH and herbicide concentrations were higher in winter than in the other seasons, although some insecticides such as chlorpyrifos were more abundant in autumn. The presence of PAHs and legacy and current-use pesticides in air confirmed their transference potential to marine coastal areas such as the Mar Menor lagoon. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. [Prevalence of metallo-beta-lactamase in carbapenem resistant Pseudomonas aeruginosa at a university hospital of Buenos Aires City].

    PubMed

    Pagniez, G; Radice, M; Cuirolo, A; Rodríguez, O; Rodríguez, H; Vay, C; Famiglietti, A; Gutkind, G

    2006-01-01

    The present study was conducted to estimate the prevalence of metallo-beta-lactamases in 91 consecutive carbapenem resistant Pseudomonas aeruginosa isolates, recovered from inpatients at Hospital de Clínicas in Buenos Aires. Both, phenotypic and genotypic methods detected the presence of carbapenemases in 10 (11%) isolates, corresponding to VIM-11 in 7/10 and VIM-2 in the others. Codifying genes were all included in class 1 integrons, upstream genes coding for aminoglycoside modifying enzymes. One hundred percent sensitivity and specificity was achieved by the metallo-beta-lactamases phenotypic screening method using EDTA (1 micromol) disks in the Pseudomonas aeruginosa isolates included in this study. Sensitivity to aztreonam in carbapenem resistant isolates was suspicious of the presence of these enzymes.

  3. Prevalence of canine dirofilariosis in the City of Buenos Aires and its outskirts (Argentina).

    PubMed

    Rosa, A; Ribicich, M; Betti, A; Kistermann, J C; Cardillo, N; Basso, N; Hallu, R

    2002-11-11

    During the past 10 years, the prevalence of canine dirofilariosis in the City of Buenos Aires and its outskirts, particularly in the northern and southern areas, has increased significantly. In the present work, studies were carried out in dogs living in the city and in its northern, western and southern outskirts from 1997 to 2001. For this purpose, 782 blood samples were collected and analyzed to determine circulating antigen, processed with the Witness Merial antigen test. The samples resulted in negative tests for subjects who lived in the city; however, 17.7 and 23.5% of the tests were positive from the northern and southern outskirts, respectively. When analyzed by sex, positive results were distributed as follows: 62.5% males and 37.5% females (P<0.05). No significant statistical difference was found on comparing purebred and cross-breds (P<0.05). It is interesting to point out the geographical distribution of the disease, which confirms that ecological factors such as water currents, abundant vegetation and the existence of mosquitoes all year round, are important for the biological cycle of Dirofilaria immitis.

  4. Places, attitudes and moments during the epidemics: representations of yellow fever and cholera in the city of Buenos Aires, 1867-1871.

    PubMed

    Fiquepron, Maximiliano Ricardo

    2018-01-01

    The goal of this article is to analyze the different representations of health and disease associated with the epidemics of yellow fever and cholera that took place from 1867-1871 in the city of Buenos Aires. It argues that there was a very broad and heterogeneous repertoire of representations that resulted in a variety of attitudes on the part of individuals dealing with the crisis, and led to the transformation of space and social time. In order to handle this traumatic experience, people chose very different methods for maintaining social contact, which was also a way of maintaining their health.

  5. 210Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina.

    PubMed

    Di Gregorio, D E; Fernández Niello, J O; Huck, H; Somacal, H; Curutchet, G

    2007-01-01

    Concentrations of (210)Pb and (137)Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The (210)Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The (137)Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere.

  6. Lagoon Restoration Project: Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    This project is a multiyear effort focusing on energy flow in the Palace of Fine Arts lagoon just outside the Exploratorium in San Francisco. Phase 1 was a pilot study to determine the feasibility of improving biological energy flow through the small freshwater lagoon, using the expertise and resources of an environmental artist in collaboration with museum biologists and arts department staff. The primary outcome of Phase 1 is an experimental fountain exhibit inside the museum designed by public artist Laurie Lundquist with Exploratorium staff. This fountain, with signage, functions both as a model for natural aeration and filtration systemsmore » and as a focal point for museum visitors to learn about how biological processes cycle energy through aquatic systems. As part of the study of the lagoon`s health, volunteers continued biweekly bird consus from March through September, 1994. The goal was to find out whether the poor water quality of the lagoon is affecting the birds. Limited dredging was undertaken by the city Parks and Recreation Department. However, a more peermanent solution to the lagoon`s ecological problems would require an ambitious redesign of the lagoon.« less

  7. Brazil The Duck Lagoon

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This Multi-angle Imaging SpectroRadiometer (MISR) image of Brazil covers an area of about 298 kilometers x 358 kilometers, and was captured by the instrument's vertical-viewing (nadir) camera on December 27, 2001. The 'Lagoa dos Patos', in the Brazilian state of Rio Grande do Sul, translates to 'the Duck Lagoon'. It was named by 16th century Jesuit settlers, who asked the King of Spain to grant them title to the lagoon so that they could breed ducks. The King consented, but revoked his edict when he discovered that the 'duck-pond' (measuring about 14,000 square kilometers) was one of the largest lagoonal systems in the world. Note the sediment plume emanating from the southern end of the lagoon. Sailors in the 16th century imagined this outlet to be the mouth of a large river. Early Portuguese explorers mistook the entrance to the lagoon for the mouth of a great river and called it the Rio Grande. A series of wave-like points and curls form 'cusps' on the inner shores of the lagoon. The lagoon's characteristics change with short-term tide-induced cyclic perturbations, and with longer term large scale meteorological conditions. The distinctive wavelike 'cusps' along the inner shores result from the circulation, erosion and accumulation of sediments driven by wind and tidal action. The El Nino Southern Oscillation (ENSO) circulation affects precipitation amount and continental runoff, thereby changing the contents of the lagoon waters. High rainfall and increased freshwater discharge during El Nino events correspond with elevated dissolved nutrient concentrations and increased phytoplankton growth. La Nina years are dry and the associated low rainfall reduces the freshwater recharge to the lagoon, causing an increase in salinity. Occasional blooms of toxic cyanobacteria (Microcystis aeruginosa), have been registered in the lagoon when nutrient concentrations are elevated. A number of reeds and grasses are important to the lagoon estuary, including widgeon grass

  8. Brazil: Duck Lagoon

    Atmospheric Science Data Center

    2013-04-18

    article title:  Brazil - The Duck Lagoon     View Larger Image ... the Brazilian state of Rio Grande do Sul, translates to "the Duck Lagoon". It was named by 16th century Jesuit settlers, who asked the King ...

  9. The FALL3D Ash Cloud Dispersion Model and its Implementation at the Buenos Aires VAAC

    NASA Astrophysics Data System (ADS)

    Folch, A.; Suaya, M.; Costa, A.; Viramonte, J.

    2009-12-01

    Airborne volcanic ash and aerosols threat aerial navigation and affect the quality of air at medium to large distances downwind from the volcano. Airplane re-routing and airport disruption carry important socioeconomic consequences at regional and national levels. Models to forecast volcanic ash clouds constitute, together with satellite imagery, a valuable predictive tool during a crisis. FALL3D is an Eulerian ash cloud dispersion model based on the advection-diffusion-sedimentation equation. The model runs at any scale, from regional to global. The dispersion model is off-line coupled with global (e.g. GFS, NMM-b) and mesoscalar (e.g. NMM-b, WRF, ETA) meteorological models and with re-analysis datasets. FALL3D has been recently installed at the Buenos Aires VAAC, depending on the Argentinean National Meteorological Service (SMN). In this presentation we summarize the characteristics of the model and its implementation at the VAAC, including the different domains, the meteorological forecast inputs (ETA or GFS) and the scenarios assumed for some critical volcanoes (Chaitén, Llaima, Lascar, etc.). Pre-defined scenarios are necessary to give an early first order prediction when data is poor or unavailable. This is particularly critical in Central Andes, were most active volcanoes are located in remote areas with poor or inexistent monitoring.

  10. Prospective Multicenter Study of Community-Associated Skin and Skin Structure Infections due to Methicillin-Resistant Staphylococcus aureus in Buenos Aires, Argentina

    PubMed Central

    López Furst, María José; de Vedia, Lautaro; Fernández, Silvina; Gardella, Noella; Ganaha, María Cristina; Prieto, Sergio; Carbone, Edith; Lista, Nicolás; Rotryng, Flavio; Morera, Graciana I.; Mollerach, Marta; Stryjewski, Martín E.

    2013-01-01

    Background Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is now the most common cause of skin and skin structure infections (SSSI) in several world regions. In Argentina prospective, multicenter clinical studies have only been conducted in pediatric populations. Objective Primary: describe the prevalence, clinical and demographic characteristics of adult patients with community acquired SSSI due to MRSA; secondary: molecular evaluation of CA-MRSA strains. Patients with MRSA were compared to those without MRSA. Materials and Methods Prospective, observational, multicenter, epidemiologic study, with molecular analysis, conducted at 19 sites in Argentina (18 in Buenos Aires) between March 2010 and October 2011. Patients were included if they were ≥14 years, were diagnosed with SSSI, a culture was obtained, and there had no significant healthcare contact identified. A logistic regression model was used to identify factors associated with CA-MRSA. Pulse field types, SCCmec, and PVL status were also determined. Results A total of 311 patients were included. CA-MRSA was isolated in 70% (218/311) of patients. Clinical variables independently associated with CA-MRSA were: presence of purulent lesion (OR 3.29; 95%CI 1.67, 6.49) and age <50 years (OR 2.39; 95%CI 1.22, 4.70). The vast majority of CA-MRSA strains causing SSSI carried PVL genes (95%) and were SCCmec type IV. The sequence type CA-MRSA ST30 spa t019 was the predominant clone. Conclusions CA-MRSA is now the most common cause of SSSI in our adult patients without healthcare contact. ST30, SCCmec IV, PVL+, spa t019 is the predominant clone in Buenos Aires, Argentina. PMID:24324543

  11. Highlights of the ecancer/SAC First International Prostate Cancer Symposium, 11–12 March 2016, Buenos Aires, Argentina

    PubMed Central

    Villalba, Marcelo Blanco; Bramajo, Marina; Bruno, Mario

    2016-01-01

    The ecancer/SAC First International Prostate Cancer Symposium, held in Buenos Aires, included national, regional, and international experts in the field of prostate cancer. More than 200 professionals from a variety of areas (clinical urologists, pathologists, oncologists, biologists, imaging specialists, radiation therapists, and generalist doctors, among others) attended, and they proposed multidisciplinary management of prostate pathology from the start in concordance with the ideas set forth by the organising committee. A radiotherapy workshop was also held during the symposium, in which new techniques and their possible uses were specifically discussed. In addition to the local doctors, Dr Lilian Faroni (COI Group, Rio de Janeiro, Brazil), Dr Leonardo Carmona (Chilean Head and Neck Institute, Chile), and Dr Anthony Addesa (Jupiter Medical Centre, Florida, USA) also participated in this symposium. PMID:27350786

  12. [From educational and health tourism for children to social tourism: vacation camps in the Province of Buenos Aires, Argentina].

    PubMed

    Bruno, Perla

    2015-12-01

    The early twentieth century saw the rise of vacation camps for frail children as educational and health-giving experiences provided by medical and philanthropic organizations. This article analyzes some of these early experiences, seen here as the predecessors of social tourism, in the Province of Buenos Aires. A combination of written sources are examined, mainly institutional reports, periodicals such as the Monitor de la Educación Común - published by the Consejo Nacional de Educación (National Board of Education) - or laws, with photographs and plans for different examples. I argue that these buildings were both physical and cultural "brands" in the places where they were located, and that their architectural structure encapsulated ideas about leisure space and cures in unique natural environments.

  13. HIV Status Disclosure Among Infected Men Who Have Sex With Men (MSM) in Buenos Aires, Argentina

    PubMed Central

    Carballo-Diéguez, Alex; Balán, Iván C.; Dolezal, Curtis; Ibitoye, Mobolaji; Pando, María A.; Marone, Rubén; Barreda, Victoria; Ávila, María Mercedes

    2013-01-01

    Five hundred men who have sex with men were recruited in Buenos Aires using respondent driven sampling. Of them, 46 respondents (24 of them not gay identified) who were HIV infected were asked questions on serodisclosure. The sample was characterized by indicators of low socioeconomic status. Most of the respondents reported being in good to excellent health despite 42% of them having been diagnosed with AIDS. Only 10% of respondents had not disclosed their serostatus to at least one person. Coworkers and lovers or main sexual partners were those most likely to know the respondents' serostatus. Reactions to disclosure were for the most part supportive. Those who had not disclosed anticipated less favorable reactions than those who had disclosed. No significant differences were observed between gay and non-gay identified respondents. The progressive social environment of Argentina that includes federal laws recognizing gay marriage may contribute to create a climate favorable for serostatus disclosure. PMID:24245593

  14. A Pleistocene (MIS 5e) mollusk assemblage from Ezeiza (Buenos Aires Province, Argentina)

    NASA Astrophysics Data System (ADS)

    Martínez, Sergio; Julia del Río, Claudia; Rojas, Alejandra

    2016-10-01

    A fossil assemblage collected around 3.5 m amsl from Ezeiza, Buenos Aires province, have AMS 14C ages of ca. 33,000 to ca. 40,000 yr BP, whereas in the literature is a report of a conventional 14C age of >43,000 yr BP. An OSL age from the overlying deposit corresponds to ca. 22,000 yr. The samples contain marine fossils: mollusks, balanids and corals (Astrangia). La Coronilla (Uruguay, attributed to MIS 5e) is the locality most related to Ezeiza faunistically, despite is not the nearest one. In consequence, the relationship should be addressed to a more similar age and environment than others. The fauna indicates a higher water temperature than today. In Ezeiza exclusively cold water taxa are absent, and we found seven warm taxa with their southern distribution limit displaced northwards today, plus other six at their southern distribution limit. Around 60% of all the species and more than 70% of the individuals are of warm-temperate waters. In sum, although prima facie the numerical ages would locate the deposit in MIS3, faunistic, temperature, and height evidences show that the Ezeiza mollusk assemblage belong to MIS5e. A stronger than presently Brazil warm current, reaching Southern latitudes, may explain the changes in geographical ranges.

  15. [History of the Department of Neurology at the University of Buenos Aires (1887-2007)].

    PubMed

    Allegri, Ricardo F; Bartoloni, Leonardo; Sica, Roberto E

    2016-07-01

    In 1887, only five years after Jean-Martin Charcot was awarded the Head of Neurology at "La Salpetrière" in Paris, José María Ramos Mejía became the first professor of Neurology in South America, at the School of Medicine of the University of Buenos Aires. Ramos Mejía convoked three assistants, the neuropathologist Christofredo Jakob, the clinician José A. Esteves and José Ingenieros. Hence it followed that Neurology in Argentina took a stand based on a clinical neurology-neuropathology approach (1941-1987) followed by a clinical-semiological attitude, finally inserting itself within the modern times (1987-present) by creating subspecialties. Throughout its history, Argentina has made remarkable contributions to Neurology, such as the diagnosis and pathogenesis of the nervous system involvement occurring in some regional endemic disorders -for instance, Chagas' disease-, the clinical approach to the diagnosis of dementias, and the pathogenesis of extrapyramidal illnesses and other primary degenerative diseases of the central nervous system, mainly amyotrophic lateral sclerosis. On the other hand, in recent years globalization allowed neurologists to participate in international cooperative projects, favoring a swifter development in the practice of this discipline.

  16. New records of forensic entomofauna in legally buried and exhumed human infants remains in Buenos Aires, Argentina.

    PubMed

    Mariani, Roxana; García-Mancuso, Rocío; Varela, Graciela L; Kierbel, Ivana

    2017-11-01

    The study of carrion fauna associated with buried human corpses from a forensic perspective could provide useful information in criminal investigations. Insects and other arthropods remains sampled of 44 legally exhumed infant skeletons from La Plata (Buenos Aires, Argentina). They were identified at different taxonomic levels depending on the state of preservation. The specific diversity, abundance and frequency were analyzed and each taxon was assigned to the hypothetical colonization sequence: burial colonization, post-exhumation contamination at cemetery deposit or soil fauna. The phorid Dohrniphora sp. is mentioned for the first time in Argentina as carrion fauna of underground colonization, and the assemblage of Dohrniphora sp., Megaselia scalaris and Hydrotaea aenescens is proposed as indicator of buried cadavers. These findings provide new useful data to be applied in forensic entomology research. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  17. Patterns of seasonal variation in lagoonal macrozoobenthic assemblages (Mellah lagoon, Algeria).

    PubMed

    Magni, Paolo; Draredja, Brahim; Melouah, Khalil; Como, Serena

    2015-08-01

    In coastal lagoons, many studies indicated that macrozoobenthic assemblages undergo marked temporal fluctuations as related to the strong environmental variability of these systems. However, most of these studies have not assessed the seasonal patterns of these fluctuations and none of them has investigated the consistency of this variation in different areas within the same lagoon system. In this study, we assessed patterns of variation at multiple temporal (date, season and year) scales in two different areas in the coastal lagoon of Mellah (northeast Algeria). These areas (hereafter Shore and Center) are representative of two different environments typically found in coastal lagoons. The Shore (water depth of about 1.5-2 m) is characterized by relatively higher hydrodynamics, sand to silty-sand sediments and the presence of vegetation (Ruppia maritima), the Center (water depth of about 3-3.5 m) is characterized by mud to sandy-mud, organic-enriched sediments due to fine particle accumulation. Results showed two distinct patterns of seasonal variation in Shore and Center assemblages for two consecutive years. In Shore, species richness (S), total abundance (N) and the abundance of several dominant taxa were highest in summer and/or autumn. This pattern can be related to the local environmental conditions maintaining relatively well oxidized conditions, while increasing food availability, and favoring the recruitment of species and individuals in summer/autumn. On the contrary in Center, S was lowest in summer and autumn, and N and the abundance of fewer dominant taxa were lowest in summer. In Center, the bivalve Loripes lucinalis showed a 10-fold increase from summer to autumn in both years, likely related to the lagoon's hydrodynamics favoring larval transport and settlement in the central sector of the lagoon. Overall, the seasonal variation found in Center followed a regression/recovery pattern typical of opportunistic assemblages occurring in confined

  18. The fate of Mediterranean lagoons under climate change

    NASA Astrophysics Data System (ADS)

    Umgiesser, Georg; Ferrarin, Christian; Cucco, Andrea; De Pascalis, Francesca; Ghezzo, Michol; Bellafiore, Debora; Bajo, Marco

    2014-05-01

    A numerical model (SHYFEM) has been applied to 10 Mediterranean lagoons and a comparison study between the lagoons has been carried out. The lagoons are the lagoons of Venice, Marano-Grado, Varano and Lesina in the Adriatic Sea, the Taranto basin in the Ionian Sea, the Cabras lagoon in Sardinia, and the lagoons of Ganzirri and Faro in Sicily, the Mar Menor in Spain and the Nador lagoon in Morocco. These lagoons give a representative picture of the lagoons situated around the Mediterranean basin. The lagoons range from a leaky type of lagoons to a choked type. The number of inlets ranges from just one in the Nador lagoon to 6 in the case of the Marano-Grado lagoons. Tidal range is from nano-tidal to micro-tidal. The depth ranges from an average depth of 1 m to up to 40 meters. The model is a finite element model, especially suited to shallow water basins with complicated geometric and morphologic variations. The model can compute the basic hydrodynamics, dispersion of tracers, temperature and salinity evolution, sediment transport and ecological parameters. Building on an earlier study that focused on the classification of Mediterranean lagoons based on hydrodynamics, exchange rates and renewal time, this study is concerned with the changes in physical parameters under climate change. Data from IPCC has been used to simulate the changes in renewal time, salinity and temperature of all lagoons, with respect to the control simulation. Whenever possible downscaled data for the Mediterranean basin have been used. Sea level rise scenarios are taken from the last IPCC report. The model has been applied in its 3D version and the chosen setup allows a comparison between results in the different lagoons. Results indicate that the differences of renewal time between all studied lagoons become smaller. This means that leaky lagoons become less leaky and choked lagoons less choked. What concerns temperature and salinity, changes occurring in the sea are amplified inside lagoons

  19. Metals in some lagoons of Mexico.

    PubMed

    Vazquez, F G; Sharma, V K; Alexander, V H; Frausto, C A

    1995-02-01

    The concentrations of metals, Cd, Cu, Fe, Mn, Ni, Pb, and Zn were determined in some lagoons to establish the level of metal pollution. The lagoons studied were Alvarado lagoon, Veracruz; San Andres lagoon, Tamaulipas; and Terminos lagoon, Campeche. The concentrations were determined in water, oyster (Crassostrea virginica), and sediments. Metals were accumulated in either oysters or sediments. Cu and Zn were higher in oysters and Fe and Mn were higher in sediments. The results in water samples were compared with the limit established by the Secretaria de Ecologia and Desarrollo Urbano Report and briefly discussed.

  20. Metals in some lagoons of Mexico.

    PubMed Central

    Vazquez, F G; Sharma, V K; Alexander, V H; Frausto, C A

    1995-01-01

    The concentrations of metals, Cd, Cu, Fe, Mn, Ni, Pb, and Zn were determined in some lagoons to establish the level of metal pollution. The lagoons studied were Alvarado lagoon, Veracruz; San Andres lagoon, Tamaulipas; and Terminos lagoon, Campeche. The concentrations were determined in water, oyster (Crassostrea virginica), and sediments. Metals were accumulated in either oysters or sediments. Cu and Zn were higher in oysters and Fe and Mn were higher in sediments. The results in water samples were compared with the limit established by the Secretaria de Ecologia and Desarrollo Urbano Report and briefly discussed. PMID:7621796

  1. Conceptual resistance in the disciplines of the mind: the Leipzig-Buenos Aires connection at the beginning of the 20th century.

    PubMed

    Taiana, Cecilia

    2005-11-01

    Personal correspondence written by Prof. Felix Krueger from Argentina in 1906-1907 to his teacher and mentor Wilhelm Wundt in Leipzig is situated in the historical context of the theoretical debates taking place at the University of Buenos Aires at the beginning of the 20th century. A critical survey of the transatlantic migration of psychological theories and their reception in Argentina raises the broader issues of the nature of the cultural and social roots of local interpretations induced by the circulation of theories across national fields of scientific inquiry. It is argued that national intellectual fields and the historicity of their categories of interpretation mediate in the foreign trade of theories.

  2. Effects of regional climate changes on the planktonic ecosystem and water environment in the frozen Notoro Lagoon, northern Japan.

    PubMed

    Katsuki, Kota; Seto, Koji; Noguchi, Takuro; Sonoda, Takeshi; Kim, JuYong

    2012-10-01

    Diatom fossils from core sediments and living diatoms from water samples of Notoro Lagoon in northern Japan were examined to evaluate natural climate effects on lagoon environmental changes. In 1974, the artificial inlet was excavated. Immediately after, the anoxic bottom water in Notoro Lagoon began to disappear due to an increasing water exchange rate. However, chemical oxygen demand (COD) in the bottom water of Notoro Lagoon gradually increased, with fluctuations, during the last 30 years. In addition, the dominant diatom assemblages in Notoro Lagoon shifted to ice-related and spring bloom taxa after the excavation. The dominant taxa of each year in the sediment core were also strongly related to the timing of lagoon ice melting. This is because the COD in Notoro Lagoon was affected by the deposited volume of blooming diatoms, which was controlled by the duration of ice cover and the timing of ice discharge to the Okhotsk Sea likely due to an air pressure pattern change over the northern North Pacific like the Pacific Decadal Oscillation (PDO). Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Aquatic insect assemblages of man-made permanent ponds, Buenos Aires city, Argentina.

    PubMed

    Fontanarrosa, M S; Collantes, M B; Bachmann, A O

    2013-02-01

    Freshwater habitats are important elements within urban green space and they are endangered by various types of human activity. With the aim to increase the knowledge about species biodiversity in urban ecosystems, we characterised the assemblages of aquatic insects in four permanent man-made ponds in Buenos Aires city (Argentina) during a 1-year period. We recorded 32 species with Sigara spp. (Hemiptera) as the most abundant. The removal of aquatic vegetation from the studied ponds may have affected both the establishment and permanence of the insect community. Swimmers were the dominant group in the studied sites, followed by burrowers and sprawlers, and only a few strictly climbers were collected. Therefore, all sampled ponds were dominated by collectors (principally gatherers), secondarily by predators and only few shredders were detected, which was much affected by the removal of macrophytes. Non-parametric abundance indexes estimated a number of species very close to the observed number in each site. Conversely, the incidence indexes estimated more species because there were many more taxa present only in one sample than those represented by few individual in a sample. Our data provides some insights on the community of man-made ponds that can improve the management of these aquatic urban habitats. Considering that macrophytes affect animal assemblages due to their role as physical structures that increase the complexity or heterogeneity of habitats, they should not be removed by authorities in order to promote biodiversity.

  4. Molecular identification of protozoa causing AIDS-associated cholangiopathy in Buenos Aires, Argentina.

    PubMed

    Nétor Velásquez, Jorge; Marta, Edgardo; Alicia di Risio, Cecilia; Etchart, Cristina; Gancedo, Elisa; Victor Chertcoff, Agustín; Bruno Malandrini, Jorge; Germán Astudillo, Osvaldo; Carnevale, Silvana

    2012-12-01

    Several species of microsporidia and coccidia are protozoa parasites responsible for cholan-giopathy disease in patients infected with human immunodeficiency virus (HIV). The goals of this work were to identift opportunistic protozoa by molecular methods and describe the clinical manifestations at the gastrointestinal tract and the biliary system in patients with AIDS-associated cholangiopathy from Buenos Aires, Argentina. This study included 11 adult HIV-infected individuals with diagnosis ofAIDS- associated cholangiopathy. An upper gastrointestinal endoscopy with biopsy specimen collection and a stool analysis for parasites were performed on each patient. The ultrasound analysis revealed bile ducts compromise. An endoscopic retrograde cholangiopancreatography and a magnetic resonance cholangiography were carried out. The identification to the species level was performed on biopsy specimens by molecular methods. Microorganisms were identified in 10 cases. The diagnosis in patients with sclerosing cholangitis was cryptosporidiosis in 3 cases, cystoisosporosis in 1 and microsporidiosis in 1. In patients with sclerosing cholangitis and papillary stenosis the diagnosis was microsporidiosis in 2 cases, cryptosporidiosis in 2 and cryptosporidiosis associated with microsporidiosis in 1. In 3 cases with cryptosporidiosis the species was Cryptosporidium hominis, 1 of them was associated with Enterocytozoon bieneusi, and the other 2 were coinfected with Cryptosporidium parvum. In the 4 cases with microsporidiosis the species was Enterocytozoon bieneusi. These results suggest that molecular methods may be useful tools to identify emerging protozoa in patients with AIDS-associated cholangiopathy.

  5. [Factors associated with academic success of medical students at Buenos Aires University].

    PubMed

    Borracci, Raúl A; Pittaluga, Roberto D; Álvarez Rodríguez, Juan E; Arribalzaga, Eduardo B; Poveda Camargo, Ricardo L; Couto, Juan L; Provenzano, Sergio L

    2014-01-01

    The aim of this study was to identify common factors relating to the academic success of medical students who were distinguished with honors at the Buenos Aires University. In 2011, 142 graduates were surveyed; the questionnaire included 59 questions on their sociodemographic environment, living conditions and social integration, motivation to study, learning capacity and health quality during their career. Compared to other students, these distinguished students more often lived in the city, far from their families; had been educated at private or universitary high schools, their economic needs were financed by their parents, who were on the whole professionals. Most of them were single and childless. The possibility of future employment oportunities (work) did not influence their choice of a medical career, academic success was important to them and they believed that success depended largely on personal effort; they knew how to handle anxiety, were sociable but independent and preferred solid experience to abstract conceptuality in order to obtain information. Our conclusion, within the current system of candidate selection, these results serve to calculate the covert self-selection mechanisms during the career, or in a more restrictive regime, to select those likely to reach academic success due to their privileged ambience. The analysis of demographic factors indicates some degree of inequality for socially disadvantaged students. Perhaps, a selection system based only on intellectual abilities would help identify and support the best candidates regardless of their social context.

  6. Ecotoxicological studies of environmental samples from Buenos Aires area using a standardized amphibian embryo toxicity test (AMPHITOX).

    PubMed

    Herkovits, Jorge; Perez-Coll, Cristina; Herkovits, Francisco D

    2002-01-01

    The toxicity of 34 environmental samples from potentially polluted and reference stations were evaluated by means of the AMPHITOX test from acute to chronic exposure according to the toxicity found in each sample. The samples were obtained from surface and ground water, leaches, industrial effluents and soils. The data, expressed in acute, short-term chronic and chronic Toxicity Units (TUa, TUstc and TUc) resulted in a maximal value of 1000 TUc, found in a leach, while the lower toxicity value was 1.4 TUa corresponding to two surface water samples. In five samples (four providing from reference places) no toxicity was detected. The results point out the possibility of evaluating the toxicity of a wide diversity of samples by means of AMPHITOX as a customized toxicity test. The fact that almost all samples with suspected toxicity in rivers and streams from the Metropolitan area of Buenos Aires city resulted toxic, indicates the need of enhanced stewardship of chemical substances for environmental and human health protection purposes.

  7. Lagoon Seepage Testing Report for Central Facilities Area (CFA) Sewage Lagoons at Idaho National Laboratory, Butte County, Idaho

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morrison, Bridger

    J-U-B ENGINEERS, Inc. (J-U-B) performed seepage tests on the CFA Wastewater Lagoons 1, 2, and 3 between August 26th and September 22nd, 2014. The lagoons were tested to satisfy the Idaho Department of Environmental Quality (DEQ) Rules (IDAPA 58.01.16) that require all lagoons be tested at a frequency of every 10 years and the Compliance Activity CA-141-03 in the DEQ Wastewater Reuse Permit for the CFA Sewage Treatment Plant (LA-000141-03). The lagoons were tested to determine if the average seepage rates are less than 0.25 in/day, the maximum seepage rate allowed for lagoons built prior to April 15, 2007. Themore » average seepage rates were estimated for each lagoon and are given in Table-ES1. The average seepage rates for Lagoons 1 and 2 are less than the allowable seepage rate of 0.25 in/day. Lagoon 1 and 2 passed the seepage test and will not have to be tested again until the year 20241. However, the average seepage rate for Lagoon 3 appears to exceed the allowable seepage rate of 0.25 in/day which means the potential source for the excessive leakage should be investigated further.« less

  8. Groundwater-driven nutrient inputs to coastal lagoons: The relevance of lagoon water recirculation as a conveyor of dissolved nutrients.

    PubMed

    Rodellas, Valentí; Stieglitz, Thomas C; Andrisoa, Aladin; Cook, Peter G; Raimbault, Patrick; Tamborski, Joseph J; van Beek, Pieter; Radakovitch, Olivier

    2018-06-16

    Evaluating the sources of nutrient inputs to coastal lagoons is required to understand the functioning of these ecosystems and their vulnerability to eutrophication. Whereas terrestrial groundwater processes are increasingly recognized as relevant sources of nutrients to coastal lagoons, there are still limited studies evaluating separately nutrient fluxes driven by terrestrial groundwater discharge and lagoon water recirculation through sediments. In this study, we assess the relative significance of these sources in conveying dissolved inorganic nutrients (NO 3 - , NH 4 + and PO 4 3- ) to a coastal lagoon (La Palme lagoon; France, Mediterranean Sea) using concurrent water and radon mass balances. The recirculation of lagoon water through sediments represents a source of NH 4 + (1900-5500 mol d -1 ) and PO 4 3- (22-71 mol d -1 ), but acts as a sink of NO 3 - . Estimated karstic groundwater-driven inputs of NO 3 - , NH 4 + and PO 4 3- to the lagoon are on the order of 200-1200, 1-12 and 1.5-8.7 mol d -1 , respectively. A comparison between the main nutrient sources to the lagoon (karstic groundwater, recirculation, diffusion from sediments, inputs from a sewage treatment plant and atmospheric deposition) reveals that the recirculation of lagoon water through sediments is the main source of both dissolved inorganic nitrogen (DIN) and phosphorous (DIP) to La Palme lagoon. These results are in contrast with several studies conducted in systems influenced by terrestrial groundwater inputs, where groundwater is often assumed to be the main pathway for dissolved inorganic nutrient loads. This work highlights the important role of lagoon water recirculation through permeable sediments as a major conveyor of dissolved nutrients to coastal lagoons and, thus, the need for a sound understanding of the recirculation-driven nutrient fluxes and their ecological implications to sustainably manage lagoonal ecosystems. Copyright © 2018. Published by Elsevier B.V.

  9. Biodegradability of Chlorophenols in Surface Waters from the Urban Area of Buenos Aires.

    PubMed

    Gallego, A; Laurino Soulé, J; Napolitano, H; Rossi, S L; Vescina, C; Korol, S E

    2018-04-01

    Biodegradability of 2-Chlorophenol (2-CP), 3-Chlorophenol (3-CP), 4-Chlorophenol (4-CP), 2,4-Dichlorophenol (2,4-DCP) and 2,4,6 Trichlorophenol (2,4,6-TCP) has been tested in surface waters in the urban area of Buenos Aires. Samples were taken from the La Plata River and from the Reconquista and Matanza-Riachuelo basins, with a total amount of 18 sampling points. Water quality was established measuring chemical oxygen demand (COD), biochemical oxygen demand (BOD 5 ), and both Escherichia coli and Enterococcus counts. Biodegradability was carried out by a respirometric method, using a concentration of 20 mg L -1 of chlorophenol, and the surface water as inoculum. Chlorophenols concentration in the same water samples were simultaneously measured by a solid phase microextraction (SPME) procedure followed by gas chromatography-mass spectrometry (GC-MS). 2,4-DCP was the most degradable compound followed by 2,4,6-TCP, 4-CP, 3-CP and 2-CP. Biodegradability showed no correlation with compound concentration. At most sampling points the concentration was below the detection limit for all congeners. Biodegradability does not correlate even with COD, BOD 5 , or fecal contamination. Biodegradability assays highlighted information about bacterial exposure to contaminants that parameters routinely used for watercourse characterization do not reveal. For this reason, they might be a helpful tool to complete the characterization of a site.

  10. Tobacco point-of-sale advertising in Guatemala City, Guatemala and Buenos Aires, Argentina

    PubMed Central

    Mejia, Raul; Szeinman, Debora; Kummerfeldt, Carlos E

    2010-01-01

    Objectives To determine tobacco point of sale advertising prevalence in Guatemala City, Guatemala and Buenos Aires, Argentina. Methods Convenience stores (120 per city) were chosen from randomly selected blocks in low, middle and high socioeconomic neighbourhoods. To assess tobacco point of sale advertising we used a checklist developed in Canada that was translated into Spanish and validated in both countries studied. Analysis was conducted by neighbourhood and store type. Results All stores sold cigarettes and most had tobacco products in close proximity to confectionery. In Guatemala, 60% of stores had cigarette ads. High and middle socioeconomic status neighbourhood stores had more indoor cigarette ads, but these differences were determined by store type: gas stations and supermarkets were more prevalent in high socioeconomic status neighbourhoods and had more indoor cigarette ads. In poorer areas, however, more ads could be seen from outside the stores, more stores were located within 100 metres of schools and fewer stores had ‘No smoking’ or ‘No sales to minors’ signs. In Argentina, 80% of stores had cigarette ads and few differences were observed by neighbourhood socioeconomic status. Compared to Guatemala, ‘No sales to minors’ signs were more prevalent in Argentina. Conclusions Tobacco point of sale advertising is highly prevalent in these two cities of Guatemala and Argentina. An advertising ban should also include this type of advertising. PMID:20530136

  11. NMVOCs speciated emissions from mobile sources and their effect on air quality and human health in the metropolitan area of Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    D'Angiola, Ariela; Dawidowski, Laura; Gomez, Dario; Granier, Claire

    2014-05-01

    Since 2007, more than half of the world's population live in urban areas. Urban atmospheres are dominated by pollutants associated with vehicular emissions. Transport emissions are an important source of non-methane volatile organic compounds (NMVOCs) emissions, species of high interest because of their negative health effects and their contribution to the formation of secondary pollutants responsible for photochemical smog. NMVOCs emissions are generally not very well represented in emission inventories and their speciation presents a high level of uncertainty. In general, emissions from South American countries are still quite unknown for the international community, and usually present a high degree of uncertainty due to the lack of available data to compile emission inventories. Within the Inter-American Institute for Global Change Research (IAI, www.iai.int) projects, UMESAM (Urban Mobile Emissions in South American Megacities) and SAEMC (South American Emissions, Megacities and Climate, http://saemc.cmm.uchile.cl/), the effort was made to compute on-road transport emission inventories for South American megacities, namely Bogota, Buenos Aires, Lima, Sao Paulo and Santiago de Chile, considering megacities as urban agglomerations with more than 5 million inhabitants. The present work is a continuation of these projects, with the aim to extend the calculated NMVOCs emissions inventory into the individual species required by CTMs. The on-road mobile sector of the metropolitan area of Buenos Aires (MABA), Argentina, accounted for 70 Gg of NMVOCs emissions for 2006, without considering two-wheelers. Gasoline light-duty vehicles were responsible for 64% of NMVOCs emissions, followed by compressed natural gas (CNG) light-duty vehicles (22%), diesel heavy-duty vehicles (11%) and diesel light-duty vehicles (7%). NMVOCs emissions were speciated according to fuel and technology, employing the European COPERT (Ntziachristos & Samaras, 2000) VOCs speciation scheme for

  12. Driving from Chicago to Buenos Aires: instrumentation courses during a road trip across the Americas

    NASA Astrophysics Data System (ADS)

    Izraelevitch, Federico

    2017-01-01

    The Escaramujo Project (www.escaramujo.net) was a series of hands-on laboratory courses on High Energy Physics and Astroparticle Instrumentation, in eight Latinamerican Institutions. The Physicist Federico Izraelevitch traveled on a van with his wife and dogs from Chicago to Buenos Aires teaching these courses. During these sessions, groups of advanced undergraduate and graduate students built a modern cosmic ray detector based on plastic scintillators and SiPMs, specifically designed for this project. With the detector as a common thread, they were able to understand the designing principles and the underlying Physics involved, build the device, start it up, characterize it, acquire data and analyze it, in the way of real particle Physics experiment. After the five-days courses, a functional detector remained at each institution to train future students and to support and enable local research activities. About a hundred talented and highly motivated students were reached out with the initiative. Besides the aims to awaken vocations in science, technology and engineering, The Escaramujo Project was an effort to strengthen the integration of academic institutions in Latin America within the international scientific community.

  13. [Sexuality, bodily experiences, and gender: an ethnographic study of persons living with HIV in Greater Metropolitan Buenos Aires, Argentina].

    PubMed

    Grimberg, Mabel

    2009-01-01

    Based on the results of an ethnographic study on daily experience with HIV in Greater Metropolitan Buenos Aires, Argentina, the article discusses behavioral approaches that reduce the sexuality of persons living with HIV to an issue of safety and protection. By articulating a social construction perspective and the notion of hegemony, the author proposes that sexuality can be understood as a process of individual and social construction shaped by power relations and social regulations. The analysis of the experiences of living with HIV in marginalized populations shows how chronic social inequality, violence, discrimination, and stigmatization generate particular characteristics of sexual issues. These social processes become driving forces that shape sexual experience as a field of danger, repression, and restriction rather than pleasure and exploration. Finally, daily confrontation with social metaphors places strain on gender relations, practices, and identities.

  14. Are coastal lagoons physically or biologically controlled ecosystems? Revisiting r vs. K strategies in coastal lagoons and estuaries

    NASA Astrophysics Data System (ADS)

    Pérez-Ruzafa, Angel; Marcos, Concepción; Pérez-Ruzafa, Isabel María; Pérez-Marcos, María

    2013-11-01

    Environmental stress influences biological assemblages, with species responding to stress by adopting particular life-history strategies (e.g., r vs. K). Coastal lagoons and estuaries are considered naturally stressed and physically controlled systems with frequent environmental disturbances and fluctuations. At the same time, their transitional nature (between terrestrial, freshwater and marine) makes them especially vulnerable to human impacts and land and freshwater inputs. As a result, it is hypothesised that residents of coastal lagoons would display characteristics of r-selected species. The r-strategy involves increased reproductive effort through early reproduction, small and numerous offspring with a large dispersive capability, short lifespan and small adult body size. Together, these traits provide a selective advantage in such unpredictable or short-lived environments. Alternatively, immigrants to coastal lagoons should mostly be K-strategists, with a competitive advantage over the r-strategists, at least on a temporary time scale. These hypotheses were explored using a dataset from 73 Atlanto-Mediterranean sites: 27 estuaries, 42 coastal lagoons and 4 from the sea, obtained from published sources. A detailed analysis of the distributions of the different resident fish species according to lagoon characteristics indicated that in lagoons with a higher marine influence the families Gobiidae, Blenniidae and Syngnathidae were common, while lagoons with freshwater influence are characterized by Cyprinidae and other freshwater species. In analyzing the biological strategies of lagoon species we found that fish assemblages inhabiting marine influenced lagoons were characterized by solitary, necto-benthonic sedentary species. These species are often hermaphroditic, with benthic broods and many exhibit brooding behaviour. This suggests that marine influenced lagoons are dominated by K-strategist species, while r-strategy species will be more common in

  15. First report of an HIV-1 triple recombinant of subtypes B, C and F in Buenos Aires, Argentina.

    PubMed

    Pando, María A; Eyzaguirre, Lindsay M; Segura, Marcela; Bautista, Christian T; Marone, Rubén; Ceballos, Ana; Montano, Silvia M; Sánchez, José L; Weissenbacher, Mercedes; Avila, María M; Carr, Jean K

    2006-09-07

    We describe the genetic diversity of currently transmitted strains of HIV-1 in men who have sex with men (MSM) in Buenos Aires, Argentina between 2000 and 2004. Nearly full-length sequence analysis of 10 samples showed that 6 were subtype B, 3 were BF recombinant and 1 was a triple recombinant of subtypes B, C and F. The 3 BF recombinants were 3 different unique recombinant forms. Full genome analysis of one strain that was subtype F when sequenced in pol was found to be a triple recombinant. Gag and pol were predominantly subtype F, while gp120 was subtype B; there were regions of subtype C interspersed throughout. The young man infected with this strain reported multiple sexual partners and sero-converted between May and November of 2004. This study reported for the first time the full genome analysis of a triple recombinant between subtypes B, C and F, that combines in one virus the three most common subtypes in South America.

  16. First molecular characterization of canine hepatozoonosis in Argentina: evaluation of asymptomatic Hepatozoon canis infection in dogs from Buenos Aires.

    PubMed

    Eiras, Diego Fernando; Basabe, Julia; Scodellaro, Carla F; Banach, Diana B; Matos, María L; Krimer, Alejandro; Baneth, Gad

    2007-11-10

    Canine hepatozoonosis is an expanding tick-borne disease in Argentina. Hepatozoonosis was studied during 1 year in six dogs from the same household in Buenos Aires. Blood parasitemia with Hepatozoon gamonts was found in five dogs and all six were positive by PCR for Hepatozoon sp. Although the levels of parasitemia fluctuated during the year, no clinical signs of disease were detected during the follow up period. Amplification and sequencing of a 650 bases fragment of the 18S rRNA gene from all six dogs yielded fragments that were 99% identical to H. canis. The results of the partial 18S rRNA genotyping with the sub-clinical course of infection and lack of severe hematological abnormalities are compatible with clinical and molecular descriptions of Hepatozoon canis infection from other areas of the world. This is the first molecular characterization of Hepatozoon from Argentina.

  17. Factors associated with infection by Campylobacter fetus in beef herds in the Province of Buenos Aires, Argentina.

    PubMed

    Jimenez, D F; Perez, A M; Carpenter, T E; Martinez, A

    2011-09-01

    Campylobacter fetus is a major venereal pathogen of cattle that is considered to be widespread among the livestock population of Argentina. The disease accounts for a 10% reduction in the weaning rate of Argentine infected herds and annual losses of $165 million. A case-control, questionnaire-based study was developed with the objective of quantifying the association between C. fetus infection and demographic, husbandry, and sanitary factors in 196 herds located in the province of Buenos Aires, Argentina. Abortions observed in the herd (OR=3.08, 95% CI=1.52, 6.23), and trespassing of bulls from neighboring herds (OR=2.03, 95% CI=0.98, 4.20), were positively associated with the risk of finding C. fetus-infected bulls, whereas buying bulls was a protective factor for the disease (OR=0.53, 95% CI=0.26, 1.08). Results presented here will help to develop and implement actions aimed at preventing the spread and reducing the incidence of C. fetus infection in the beef cattle population of Argentina. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Aerated Lagoons. Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Andersen, Lorri

    This student manual contains the textual material for a unit which focuses on the structural and operationally unique features of aerated lagoons. Topic areas discussed include: (1) characteristics of completely mixed aerated lagoons; (2) facultative aerated lagoons; (3) aerated oxidation ponds; (4) effects of temperature on aerated lagoons; (5)…

  19. [New documental evidence on the history of homeopathy in Latin America: a case study of links between Rio de Janeiro and Buenos Aires].

    PubMed

    Tarcitano, Conrado Mariano; Waisse, Silvia

    2016-01-01

    Homeopathy began to spread soon after it was formulated by Samuel Hahnemann in the early 1800s, reaching the Southern Cone in the 1830s. In processes of this kind, one figure is often cited as being responsible for introducing it, often attaining quasi-mythical status. Little is known, however, about how homeopathy reached Argentina at that time. Through archival research, we discovered that medical and lay homeopaths circulated between Rio de Janeiro and Buenos Aires. Given the well-known proselytizing of the circles gravitating around lay homeopaths B. Mure and J.V. Martins in Rio de Janeiro, the documents indicate that this movement actually went as far as Argentina, which had not been confirmed until now.

  20. Water quality and nitrogen mass loss from anaerobic lagoon columns receiving pretreated influent

    USDA-ARS?s Scientific Manuscript database

    Control methods are needed to abate ammonia losses from swine anaerobic lagoons to reduce contribution of confined swine operations to air pollution. In a 15-month meso-scale column study, we evaluated the effect of manure pretreatment on water quality, reduction of N losses, and sludge accumulation...

  1. Temporal coherence among tropical coastal lagoons: a search for patterns and mechanisms.

    PubMed

    Caliman, A; Carneiro, L S; Santangelo, J M; Guariento, R D; Pires, A P F; Suhett, A L; Quesado, L B; Scofield, V; Fonte, E S; Lopes, P M; Sanches, L F; Azevedo, F D; Marinho, C C; Bozelli, R L; Esteves, F A; Farjalla, V F

    2010-10-01

    Temporal coherence (i.e., the degree of synchronicity of a given variable among ecological units within a predefined space) has been shown for several limnological features among temperate lakes, allowing predictions about the structure and function of ecosystems. However, there is little evidence of temporal coherence among tropical aquatic systems, where the climatic variability among seasons is less pronounced. Here, we used data from long-term monitoring of physical, chemical and biological variables to test the degree of temporal coherence among 18 tropical coastal lagoons. The water temperature and chlorophyll-a concentration had the highest and lowest temporal coherence among the lagoons, respectively, whereas the salinity and water colour had intermediate temporal coherence. The regional climactic factors were the main factors responsible for the coherence patterns in the water temperature and water colour, whereas the landscape position and morphometric characteristics explained much of the variation of the salinity and water colour among the lagoons. These results indicate that both local (lagoon morphometry) and regional (precipitation, air temperature) factors regulate the physical and chemical conditions of coastal lagoons by adjusting the terrestrial and marine subsidies at a landscape-scale. On the other hand, the chlorophyll-a concentration appears to be primarily regulated by specific local conditions resulting in a weak temporal coherence among the ecosystems. We concluded that temporal coherence in tropical ecosystems is possible, at least for some environmental features, and should be evaluated for other tropical ecosystems. Our results also reinforce that aquatic ecosystems should be studied more broadly to accomplish a full understanding of their structure and function.

  2. Multi-centennial scale precipitation and following lagoon ecosystem fluctuation in the Holocene reconstructed by East Korean Lagoon sediment analysis

    NASA Astrophysics Data System (ADS)

    Katsuki, K.; Yang, D. Y.; Lim, J.; Nahm, W. H.; Nakanishi, T.; Seto, K.; Otsuka, M.; Kashima, K.

    2014-12-01

    There are lagoons in the northern east coast of the South Korea, which were formed during the transgression period in the early Holocene. These lagoons shrank about 5-30 % during the first half of 20 century due to terrestrial sediment input from soil erosion in reclamation lands. However, buried lagoonal sediments record Holocene climate change. In this study, multi-centennial scale paleo-climate and paleo-ecosystem change were investigated by analysis of this buried and present lagoon deposits. Based on the diatom assemblage analysis of the sediment in the lagoon Maeho where it is the east coast lagoons in Korea, this lagoon was formed about 8,400 years ago, and halophilic diatoms showed high peaks at three times within the last 8,400 years. Timings of these peaks were well coincident with the high-sea level periods reported in the western Japan. It is considered that sea-level of the east coast in Korea also showed high at three times during the mid-late Holocene, and then, salinity of the lagoon increased in these periods. Except for such sea-level dependent change, salinity of the lagoon Maeho showed the multi-centennial (200 or 400 years) scale periodic variation. Magnetic susceptibility (MS) also showed the clear 400 years periodicity in the mid-late Holocene. When the MS showed high value, oligohalobous diatoms showed high value. However, halophilic diatoms and number of total diatom valves increased when the MS showed low value. This correspondence probably indicates that magnetic minerals flew into the lagoon with river fresh water, and then volume of fresh water inflow has changed with 400 years cycles. Such MS cycle was also confirmed in the sediments of other lagoons. Change of fresh water inflow should be not local event, was a part of regional environmental change. These results probably indicate that the precipitation on the northeastern South Korea has changed by the 400 years cycle. On the basis of lagoon bottom sediment, it made clear that the

  3. Tuberculosis transmission of predominant genotypes of Mycobacterium tuberculosis in northern suburbs of Buenos Aires city region.

    PubMed

    Morcillo, N; Zumarraga, M; Imperiale, B; Di Giulio, B; Chirico, C; Kuriger, A; Alito, A; Kremer, K; Cataldi, A

    2007-01-01

    In 2003, the incidence of tuberculosis in Argentina showed an increase compared to 2002. The severe national crisis at the end of the 90s has probably strongly contributed to this situation. The goal of this work was to estimate the extent of the spread of the most predominant Mycobacterium tuberculosis strains and to assess the spread of predominant M. tuberculosis clusters as determined by spoligotyping and IS6110 RFLP. The study involved 590 pulmonary, smear-positive TB cases receiving medical attention at health centers and hospitals in Northern Buenos Aires (NBA) suburbs, from October 2001 to December 2002. From a total of 208 clinical isolates belonging to 6 major clusters, 63 (30.2%) isolates had identical spoligotyping and IS6110 RFLP pattern. Only 22.2% were shown to have epidemiological connections with another member of their respective cluster. In these major clusters, 30.2% of the 208 TB cases studied by both molecular techniques and contact tracing could be convincingly attributable to a recently acquired infection. This knowledge may be useful to assess the clonal distribution of predominant M. tuberculosis clusters in Argentina, which may make an impact on TB control strategies.

  4. New toxics, new poverty: a social understanding of the freebase cocaine/Paco in Buenos Aires, Argentina.

    PubMed

    Epele, María E

    2011-01-01

    Included within the field of research on changes in drug use patterns and vulnerability are conditions of emergency related to economic crisis, wars, and political conflict. This study addresses the complex connections between the rapid propagation of freebase cocaine (FBC)-locally known as "pasta base" or "Paco" in Argentina and the normalization of the consequences of Argentina's 2001-2002 political-economic crisis. On the basis of the results of an ethnographic study carried out in three neighborhoods of the Greater Buenos Aires area between 2001 and 2005, this article aims to analyze how changes in the material and social living conditions are interrelated with the high toxicity of FBC/Paco and engender the emerging compulsion of its consumption and deterioration to the bodies, subjectivities, and social activities of active drug users from these shantytowns. By analyzing the changes in transactions directly or indirectly involving drugs-specifically those ranging from cocaine to FBC/Paco-we can argue how structural poverty, "new poverty," is not only associated with the expansion of FBC/Paco but is also shaped by its use, modes of consumption, associated health problems, and sufferings.

  5. Tire-breeding mosquitoes of public health importance along an urbanisation gradient in Buenos Aires, Argentina.

    PubMed

    Rubio, Alejandra; Cardo, María Victoria; Vezzani, Darío

    2011-09-01

    Used vehicle tires are a source of mosquito vectors and a means of their introduction and expansion. With the aim of assessing the effects of urbanisation on the main mosquito vectors in temperate Argentina, the infestation levels of Aedes aegypti (L.) and Culex pipiens L. were studied in used tires from highly urbanised cities to low-urbanised small towns in Buenos Aires. Immatures of both species accounted for 96% of the 9,722 individuals collected; the total individuals collected represented seven species. The percentage of water-filled tires containing mosquitoes [container index (CI)] was 33% and the percentage of infested sites [site index (SI)] was 65.2%. These indexes decreased significantly from low to high urbanisation levels for both mosquito species. The relative abundance (RA) of Ae. aegypti immatures was slightly higher toward large cities, but showed no difference for Cx. pipiens. The CI of shaded tires was significantly higher than the CI of exposed tires for both mosquito species. There was no difference in RA values between shaded and sunlit tires. The CI and the SI were highest during the summer across the urbanisation levels, except for Cx. pipiens, which continued to increase during the autumn in small towns. Results related to urbanisation gradient, sunlit exposure and seasonality are discussed.

  6. [Scientific research in public health institutions of the City of Buenos Aires].

    PubMed

    Ferrero, Fernando; Ossorio, María Fabiana; Eiguch, Kumiko

    2013-01-01

    Hospitals with academic activities offer better services to their patients. The Government of Buenos Aires City (GBAC) has an important network of health facilities, but there is little information regarding their academic activities. Our aim was to estimate the proportion of articles included in MEDLINE originated in GBAC hospitals, to evaluate their contribution regarding the whole country (Argentina), and to describe some characteristics of these papers. It is a cross-sectional study based on a MEDLINE search, using the name of each of the 33 GBAC hospitals in the "affiliation" field. Among 22 million references, 1781 belonged to GBAC hospitals (4.4% of all references from Argentina); 66.5% were in English, 83.7% were related to humans, 30.1% were from the last 5 years, 8.3% included high level scientific evidence research (meta-analysis or randomized controlled trials), and 31.1% included research in children. Regarding the rest of the references from Argentina, those from GBAC hospitals included less papers in English (66.5% vs. 90.0%; OR: 0.22; p < 0.0001), less recent papers (30.1% vs. 34.6%; OR: 0.81; p < 0.0001), more research in humans (83.7% vs. 37.3%; OR: 8.65; p < 0.0001), more randomized controlled trials (8.0% vs. 2.8%; OR: 2,9; p < 0.0001), and more research in children (31.1% vs. 9.2%; OR: 4.44; p < 0.0001). GBAC hospitals contributed with 4.4% of references attributed to Argentina in MEDLINE. References from GBAC hospitals were less recent, and included more randomized controlled trials and research in children.

  7. Children’s palliative care now! Highlights from the second ICPCN conference on children’s palliative care, 18–21 May 2016, Buenos Aires, Argentina

    PubMed Central

    Downing, J; Kiman, R; Boucher, S; Nkosi, B; Steel, B; Marston, C; Lascar, E; Marston, J

    2016-01-01

    The International Children’s Palliative Care Network held its second international conference on children’s palliative care in Buenos Aires, Argentina, from the 18th–21st May 2016. The theme of the conference was ‘Children’s Palliative Care…. Now!’ emphasising the need for palliative care for children now, as the future will be too late for many of them. Six pre-conference workshops were held, addressing issues connected to pain assessment and management, adolescent palliative care, ethics and decision-making, developing programmes, the basics of children’s palliative care, and hidden aspects of children’s palliative care. The conference brought together 410 participants from 40 countries. Plenary, concurrent, and poster presentations covered issues around the status of children’s palliative care, genetics, perinatal and neonatal palliative care, the impact of children’s palliative care and the experiences of parents and volunteers, palliative care as a human right, education in children’s palliative care, managing complex pain in children, spiritual care and when to initiate palliative care. The ‘Big Debate’ explored issues around decision-making and end of life care in children, and gave participants the opportunity to explore a sensitive and thought provoking topic. At the end of the conference, delegates were urged to sign the Commitment of Buenos Aires which called for governments to implement the WHA resolution and ensure access to palliative care for neonates, children and their families, and also commits us as palliative care providers to share all that we can and collaborate with each other to achieve the global vision of palliative care for all children who need it. The conference highlighted the ongoing issues in children’s palliative care and participants were continually challenged to ensure that children can access palliative care NOW. PMID:27610193

  8. Quality of life in type 2 diabetes mellitus patients requiring insulin treatment in Buenos Aires, Argentina: a cross-sectional study

    PubMed Central

    Pichon-Riviere, Andres; Irazola, Vilma; Beratarrechea, Andrea; Alcaraz, Andrea; Carrara, Carolina

    2015-01-01

    Background: Decision-makers have begun to recognize Health-Related Quality of Life (HRQoL) as an important and measurable outcome of healthcare interventions; and HRQoL data is increasingly being used by policy-makers to prioritize health resources. Our objective was to measure HRQoL in a group of Type 2 Diabetes Mellitus (T2DM) patients receiving insulin treatment in Buenos Aires, Argentina. Methods: We conducted a cross-sectional study of patients with T2DM over 21 years of age, treated with either Neutral Protamine Hagedorn (NPH) insulin or Insulin Glargine (IG), who had not changed their baseline schedule in the last 6 months. The recruitment was during 2006–7 in nine private diabetes specialists’ offices in Buenos Aires, Argentina. A standardized diabetes-specific HRQoL questionnaire, the Audit of Diabetes Dependent Quality of Life (ADDQoL), was used. Results: A total of 183 patients were included (93 receiving NPH and 90 receiving IG). The mean QoL score was: 0.98 (SD: 0.89) and the diabetes specific QoL was: -1.49 (SD: 0.90). T2DM had a negative impact on HRQoL with a mean Average Weighted Impact (AWI) score on QoL of -1.77 (SD: 1.58). The greatest negative impact was observed for domains: ‘worries about the future’, ‘freedom to eat’, ‘living conditions’, ‘sex life’, and ‘family life’. The mean AWI score was -1.71 (SD: 1.48) in patients treated with IG and -1.85 (SD: 1.68) in patients receiving NPH, this difference was not statistically significant. Conclusion: The ADDQoL questionnaire is a tool that can be used in Argentina to measure the QoL of patients with diabetes when evaluating diabetes care programs. The scores of QoL in our selected population did not differ from those reported in high-income countries. We expect that the results of this study will increase healthcare providers’ awareness of patients’ perceived QoL and help to overcome the barriers that delay insulin treatment; mainly clinical inertia and patient

  9. Atopic dermatitis and risk factors in poor children from Great Buenos Aires, Argentina.

    PubMed

    Dei-Cas, I; Dei-Cas, P; Acuña, K

    2009-04-01

    In recent decades, the prevalence of atopic dermatitis (AD) has risen steadily, and risk factors for AD are currently being investigated worldwide. In Argentina, there are no available data on risk factors of AD. To determine the prevalence of and any gender predilection for AD, and to identify familial and environmental factors that are associated with increased AD risk. In this case-control cross sectional study, 603 children aged 12-60 months old from a poor urban community in Buenos Aires were recruited. AD was defined following UK Working Party Diagnostic Criteria. We evaluated the relationship between AD and the presence of family history of atopy, > 5 family members, wearing synthetic clothes, having a carpeted room, eating > or = 3 eggs/week, tobacco smoking indoors by family members, and living< 300 m from a main road, polluted stream or industry. The prevalence of AD was 41.1% (95% CI 37.2-45.2%). Logistic regression analysis showed that AD was significantly associated only with a family history of atopy (OR = 5.7; 95% CI 3.7-8.8%; P = 0.0000), wearing synthetic clothes (OR = 2.2; 95% CI 1.4-3.5; P = 0.0009), having a carpeted room OR = 1.9; 95% CI 1.2-3.0%; P = 0.009) and living < 300 m from an industry (OR = 1.93; 95% CI 1.2-3.1%; P = 0.0051). We found a high prevalence of AD in our study population. Not all the investigated risk factors for AD had a significant association with the disease.

  10. Flushing of a coastal lagoon in the Red Sea

    NASA Astrophysics Data System (ADS)

    Sultan, S. A. R.; Ahmad, F.

    1990-09-01

    Shu'aiba Lagoon (Lat. 20°45'N; Long. 39°28'E) is located on the eastern coast of the Red Sea. It is relatively shallow with an area of approximately 11·7 km 2. The inlet to the lagoon is narrow with a cross-sectional area of about 245 m 2. This lagoon is a future site to develop mariculture. With this objective in view the flushing time scale of the lagoon was calculated, as flushing is an important abiotic factor in lagoon ecology. The average flushing time for the months February to June and September to November is about 20 days. Oceanic inputs play an important part in the process of fertilization of the lagoons. The marine environment in arid zone lagoons is under natural stress due to high temperatures and salinities. However, the flushing time scale of 20 days may not exert intolerable stress on the ecology of the Shu'aiba Lagoon.

  11. High-resolution chronology for deglaciation of the Patagonian Ice Sheet at Lago Buenos Aires (46.5°S) revealed through varve chronology and Bayesian age modelling

    NASA Astrophysics Data System (ADS)

    Bendle, Jacob M.; Palmer, Adrian P.; Thorndycraft, Varyl R.; Matthews, Ian P.

    2017-12-01

    Glaciolacustrine varves offer the potential to construct continuous, annually-resolved chronologies for ice-sheet deglaciation, and improved understanding of glacier retreat dynamics. This paper investigates laminated glaciolacustrine sediments deposited around the waning margins of the Patagonian Ice Sheet, following the local Last Glacial Maximum (LGM). Detailed macro- and microfacies analyses confirm an annual (varve) structure within these sediments. The correlation of annual layers (varves) across five sites in eastern Lago Buenos Aires yields a 994 ± 36 varve-year (vyr) chronology and thickness record. The floating chronology has been anchored to the calendar-year timescale through identification of the Ho tephra (17,378 ± 118 cal a BP) in the varve sequences. Using a Bayesian age model to integrate the new varve chronology with published moraine ages, the onset of deglaciation at 46.5°S is dated to 18,086 ± 214 cal a BP. New age estimates for deglacial events are combined with high-resolution analysis of varve thickness trends, and new lithostratigraphic data on ice-margin position(s), to reconstruct ice-margin retreat rates for the earliest ca. 1000 years of ice-sheet demise. Glacier retreat rates were moderate (5.3-10.3 m yr-1) until 17,322 ± 115 cal a BP, but subsequently accelerated (15.4-18.0 m yr-1). Sustained influxes of ice-rafted debris (IRD) after 17,145 ± 122 cal a BP suggest retreat rates were enhanced by calving after ice contracted into deeper lake waters. Ice persisted in eastern Lago Buenos Aires until at least 16,934 ± 116 cal a BP, after which the glacier started to retreat towards the Patagonian mountains.

  12. Implementation of a 3D Coupled Hydrodynamic and Contaminant Fate Model for PCDD/Fs in Thau Lagoon (France): The Importance of Atmospheric Sources of Contamination

    PubMed Central

    Dueri, Sibylle; Marinov, Dimitar; Fiandrino, Annie; Tronczyński, Jacek; Zaldívar, José-Manuel

    2010-01-01

    A 3D hydrodynamic and contaminant fate model was implemented for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in Thau lagoon. The hydrodynamic model was tested against temperature and salinity measurements, while the contaminant fate model was assessed against available data collected at different stations inside the lagoon. The model results allow an assessment of the spatial and temporal variability of the distribution of contaminants in the lagoon, the seasonality of loads and the role of atmospheric deposition for the input of PCDD/Fs. The outcome suggests that air is an important source of PCDD/Fs for this ecosystem, therefore the monitoring of air pollution is very appropriate for assessing the inputs of these contaminants. These results call for the development of integrated environmental protection policies. PMID:20617040

  13. Inverse-dispersion technique for assessing lagoon gas emissions

    USDA-ARS?s Scientific Manuscript database

    Measuring gas emissions from treatment lagoons and storage ponds poses challenging conditions for existing micrometeorological techniques because of non-ideal wind conditions, such as those induced by trees and crops surrounding the lagoons, and lagoons with dimensions too small to establish equilib...

  14. Investigating flight response of Pacific brant to helicopters at Izembek Lagoon, Alaska by using logistic regression

    USGS Publications Warehouse

    Erickson, Wallace P.; Nick, Todd G.; Ward, David H.; Peck, Roxy; Haugh, Larry D.; Goodman, Arnold

    1998-01-01

    Izembek Lagoon, an estuary in Alaska, is a very important staging area for Pacific brant, a small migratory goose. Each fall, nearly the entire Pacific Flyway population of 130,000 brant flies to Izembek Lagoon and feeds on eelgrass to accumulate fat reserves for nonstop transoceanic migration to wintering areas as distant as Mexico. In the past 10 years, offshore drilling activities in this area have increased, and, as a result, the air traffic in and out of the nearby Cold Bay airport has also increased. There has been a concern that this increased air traffic could affect the brant by disturbing them from their feeding and resting activities, which in turn could result in reduced energy intake and buildup. This may increase the mortality rates during their migratory journey. Because of these concerns, a study was conducted to investigate the flight response of brant to overflights of large helicopters. Response was measured on flocks during experimental overflights of large helicopters flown at varying altitudes and lateral (perpendicular) distances from the flocks. Logistic regression models were developed for predicting probability of flight response as a function of these distance variables. Results of this study may be used in the development of new FAA guidelines for aircraft near Izembek Lagoon.

  15. Comparative study of urban development and groundwater condition in coastal areas of Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Rodrigues Capítulo, Leandro; Carretero, Silvina C.; Kruse, Eduardo E.

    2017-08-01

    The geomorphological evolution of a sand-dune barrier in Buenos Aires, Argentina, is analyzed as a factor regulating the fresh groundwater reserves available. The impact of geomorphological evolution and the consequences for the social and economic development of two coastal areas are assessed. This is one of the most important tourist destinations in the country; for study purposes, it was divided into a northern sector and a southern sector. In the southern sector, the exploitable groundwater is associated with the Holocene and upper Pleistocene geomorphological evolution, which generated three interrelated aquifer units, constituting a system whose useful thickness reaches at least 45 m. In contrast, the northern sector is restricted to two Holocene aquifer units, whose total thickness is on the order of 12 m. The morphological characteristics and the occurrence of the largest fresh groundwater reserves in the southern sector are indicators of better conditions for economic growth, which is mainly reflected on the expansion of real estate ventures. The relationships of transmissivity vs area of real estate ventures (Arev), and total water consumption vs Arev, are indicators for the sustainable management of the water resources. The approach chosen may be used by decision makers in other regions to assess the feasibility of future tourism projects on the basis of the availability of water resources associated with geomorphological features.

  16. [Fungal biomass estimation in soils from southwestern Buenos Aires province (Argentina) using calcofluor white stain].

    PubMed

    Vázquez, María B; Amodeo, Martín R; Bianchinotti, María V

    Soil microorganisms are vital for ecosystem functioning because of the role they play in soil nutrient cycling. Agricultural practices and the intensification of land use have a negative effect on microbial activities and fungal biomass has been widely used as an indicator of soil health. The aim of this study was to analyze fungal biomass in soils from southwestern Buenos Aires province using direct fluorescent staining and to contribute to its use as an indicator of environmental changes in the ecosystem as well as to define its sensitivity to weather conditions. Soil samples were collected during two consecutive years. Soil smears were prepared and stained with two different concentrations of calcofluor, and the fungal biomass was estimated under an epifluorescence microscope. Soil fungal biomass varied between 2.23 and 26.89μg fungal C/g soil, being these values in the range expected for the studied soil type. The fungal biomass was positively related to temperature and precipitations. The methodology used was reliable, standardized and sensitive to weather conditions. The results of this study contribute information to evaluate fungal biomass in different soil types and support its use as an indicator of soil health for analyzing the impact of different agricultural practices. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Prevalence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis) at Buenos Aires National Wildlife Refuge, Arizona, USA

    USGS Publications Warehouse

    Sigafus, Brent H.; Hossack, Blake R.; Muths, Erin L.; Schwalbe, Cecil R.

    2014-01-01

    Information on disease presence can be of use to natural resource managers, especially in areas supporting threatened and endangered species that occur coincidentally with species that are suspected vectors for disease. Ad hoc reports may be of limited utility (Muths et al. 2009), but a general sense of pathogen presence (or absence) can inform management directed at T&E species, especially in regions where disease is suspected to have caused population declines (Bradley et al. 2002). The Chiricahua Leopard Frog (Lithobates chiricahuensis), a species susceptible to infection by the amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) (Bradley et al. 2002), and the non-native, invasive American Bullfrog (L. catesbeianus), a suspected vector for chytridiomycosis (Schloegel et al. 2012, Gervasi et al. 2013), both occur at Buenos Aires National Wildlife Refuge (BANWR) and surrounding lands in southern Arizona. Efforts to eradicate the bullfrog from BANWR began in 1997 (Suhre, 2010). Eradication from the southern portion of BANWR was successful by 2008 but the bullfrog remains present at the Arivaca Cienega and in areas immediately adjacent to the refuge (Fig. 1). Curtailing the re-invasion of the bullfrog into BANWR will require vigilance as to ensure the health of Chiricahua Leopard Frog populations.

  18. Molecular typing of Treponema pallidum isolates from Buenos Aires, Argentina: Frequent Nichols-like isolates and low levels of macrolide resistance

    PubMed Central

    Gallo Vaulet, Lucía; Grillová, Linda; Mikalová, Lenka; Casco, Ricardo; Rodríguez Fermepin, Marcelo; Pando, María A.; Šmajs, David

    2017-01-01

    A total of 54 clinical samples, including genital lesion swabs, whole blood and cerebrospinal fluid from patients diagnosed with syphilis were collected in 2006 and in 2013 in Buenos Aires, Argentina. Treponemal DNA was detected in 43 of the analyzed samples (79.6%) and further analyzed using Sequencing-based molecular typing (SBMT) and Enhanced CDC-typing (ECDCT). By SBMT, 10 different Treponema pallidum subsp. pallidum (TPA) genotypes were found, of which six were related to the TPA SS14 strain, and four to the TPA Nichols strain. The 23S rRNA gene was amplified in samples isolated from 42 patients, and in six of them (14.3%), either the A2058G (four patients, 9.5%) or the A2059G (two patients, 4.8%) mutations were found. In addition to Taiwan, Madagascar and Peru, Argentina is another country where the prevalence of Nichols-like isolates (26.8%) is greater than 10%. PMID:28235102

  19. Molecular typing of Treponema pallidum isolates from Buenos Aires, Argentina: Frequent Nichols-like isolates and low levels of macrolide resistance.

    PubMed

    Gallo Vaulet, Lucía; Grillová, Linda; Mikalová, Lenka; Casco, Ricardo; Rodríguez Fermepin, Marcelo; Pando, María A; Šmajs, David

    2017-01-01

    A total of 54 clinical samples, including genital lesion swabs, whole blood and cerebrospinal fluid from patients diagnosed with syphilis were collected in 2006 and in 2013 in Buenos Aires, Argentina. Treponemal DNA was detected in 43 of the analyzed samples (79.6%) and further analyzed using Sequencing-based molecular typing (SBMT) and Enhanced CDC-typing (ECDCT). By SBMT, 10 different Treponema pallidum subsp. pallidum (TPA) genotypes were found, of which six were related to the TPA SS14 strain, and four to the TPA Nichols strain. The 23S rRNA gene was amplified in samples isolated from 42 patients, and in six of them (14.3%), either the A2058G (four patients, 9.5%) or the A2059G (two patients, 4.8%) mutations were found. In addition to Taiwan, Madagascar and Peru, Argentina is another country where the prevalence of Nichols-like isolates (26.8%) is greater than 10%.

  20. Nitrogen Species in Soil, Sediment, and Ground Water at a Former Sewage-Treatment Wastewater Lagoon: Naval Air Station Whidbey Island, Island County, Washington

    USGS Publications Warehouse

    Cox, S.E.; Dinicola, R.S.; Huffman, R.L.

    2007-01-01

    The potential for contamination of ground water from remnant sewage sludge in re-graded sediments of a deconstructed sewage-treatment lagoon was evaluated. Ground-water levels were measured in temporary drive-point wells, and ground-water samples were collected and analyzed for nutrients and other water-quality characteristics. Composite soil and sediment samples were collected and analyzed for organic carbon and nitrogen species. Multiple lines of evidence, including lack of appreciable organic matter in sediments of the former lagoon, agronomic analysis of nitrogen, the sequestration of nitrogen in the developing soils at the former lagoon, and likely occurrence of peat deposits within the aquifer material, suggest that the potential for substantial additions of nitrogen to ground water beneath the former sewage lagoon resulting from remnant sewage sludge not removed from the former lagoon are small. Concentrations of nitrogen species measured in ground-water samples were small and did not exceed the established U.S. Environmental Protection Agency's maximum contaminant levels for nitrate (10 milligrams per liter). Concentrations of nitrate in ground-water samples were less than the laboratory reporting limit of 0.06 milligram per liter. Seventy to 90 percent of the total nitrogen present in ground water was in the ammonia form with a maximum concentration of 7.67 milligrams per liter. Concentrations of total nitrogen in ground water beneath the site, which is the sum of all forms of nitrogen including nitrate, nitrite, ammonia, and organic nitrogen, ranged from 1.15 to 8.44 milligrams per liter. Thus, even if all forms of nitrogen measured in ground water were converted to nitrate, the combined mass would be less than the maximum contaminant level. Oxidation-reduction conditions in ground water beneath the former sewage lagoon were reducing. Given the abundant supply of ambient organic carbon in the subsurface and in ground water at the former lagoon, any

  1. Mercury Concentrations in Coastal Sediment from Younger Lagoon, Central California

    NASA Astrophysics Data System (ADS)

    Hohn, R. A.; Ganguli, P. M.; Swarzenski, P. W.; Richardson, C. M.; Merckling, J.; Johnson, C.; Flegal, A. R.

    2013-12-01

    Younger Lagoon Reserve, located in northern Monterey Bay, is one of the few relatively undisturbed wetlands that remain along the Central Coast of California. This lagoon system provides protected habitat for more than 100 bird species and for populations of fish, mammals, and invertebrates. Total mercury (HgT) concentrations in water within Younger Lagoon appear to vary with rainfall conditions and range from about 5-15 pM. These concentrations are similar to HgT in water from six nearby lagoon systems. However, Younger Lagoon contains elevated concentrations of dissolved organic carbon (~1 mM) and monomethylmercury (MMHg, ~1 pM) relative to our comparison lagoon sites (DOC < 0.5 mM and MMHg < 0.5 pM). We attribute Younger Lagoon's high DOC and MMHg to its restricted connection to the ocean and minor riverine contribution. Coastal lagoons in this region typically form at the mouth of streams. They behave as small estuaries during the wet season when surface water discharge keeps the mouth of the stream open to the ocean, and then transition into lagoons in the dry season when a sand berm develops and effectively cuts off surface water exchange. At Younger Lagoon, the sand berm remains intact throughout the year, breaching only during particularly high tides or intense rain events. Therefore, the lagoon's connection to nearshore seawater is primarily via surface water - groundwater interaction through the sand berm. Because Younger Lagoon is largely isolated from a surface water connection with the ocean, runoff from upgradient urban and agricultural land has an enhanced impact on water (and presumably sediment) quality. As a result, the lagoon is eutrophic and experiences annual algal blooms. Groundwater surveys suggest surface water, groundwater, and coastal seawater are hydraulically connected at Younger Lagoon, and mixing among these water masses appears to influence water geochemistry. To date, no chemical analyses have been conducted on sediment from Younger

  2. High Prevalence of Substance Use among Men who have Sex with Men in Buenos Aires, Argentina: Implications for HIV Risk Behavior

    PubMed Central

    Balán, Iván C.; Carballo-Diéguez, Alex; Dolezal, Curtis; Marone, Rubén; Pando, María A.; Barreda, Victoria; Ávila, María M

    2012-01-01

    Five hundred gay and other men who have sex with men (G&MSM) from Buenos Aires, Argentina completed an assessment regarding substance use and sexual behavior. During the past two months, 78% of participants consumed alcohol and 61% drugs. Over 20% of participants reporting alcohol, marijuana, cocaine sulfate, or tranquilizer use, did so daily. Heavy alcohol use was more likely among participants with greater mood reactivity (AOR = 1.64) and less likely among those who identified as gay (AOR=0.38). Weekly drug use was less likely among older (AOR=0.98), and gay-identified participants (AOR=0.50), but more likely among participants with greater mood reactivity (AOR=1.49). Drug use was correlated with unprotected anal and vaginal intercourse with men, women, and transvestites among non-gay identified participants (r= 0.22). Findings highlight the need to reduce substance use and sexual risk behavior in this population. PMID:23196860

  3. [The evaluation of psychological development in the dispensarios de lactantes (infant and toddler clinics) in Buenos Aires: medicine and psychology in Argentina, 1935-1942].

    PubMed

    Briolotti, Ana

    2016-01-01

    This article explores the medical use of techniques for psychological evaluation in the dispensarios de lactantes (infant and toddler clinics) in Buenos Aires within the framework of historical studies of psychology in Argentina. It analyzes the institutional environment in order to shed light on the framework of discourses within which the interest in controlling psychological development may be situated. It studies the tests used, the characteristics of application and the most significant results. It explores the vicissitudes of the professional field, in the light of which psychology was useful for consolidating the legitimacy of medical knowledge. It points out a divergence between this medical use of psychology and the production and circulation of psychological knowledge in academic and educational environments.

  4. Facultative Lagoons. Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Andersen, Lorri

    The textual material for a unit on facultative lagoons is presented in this student manual. Topic areas discussed include: (1) loading; (2) microbial theory; (3) structure and design; (4) process control; (5) lagoon start-up; (6) data handling and analysis; (7) lagoon maintenance (considering visual observations, pond structure, safety, odor,…

  5. A Century of changes for Razelm-Sinoe Lagoon System

    NASA Astrophysics Data System (ADS)

    Scrieciu, Marian-Albert; Stanica, Adrian

    2014-05-01

    A Century of changes for Razelm-Sinoe Lagoon System Marian-Albert Scrieciu (a), Adrian Stanica (a) (a) National Institute of Marine Geology and Geoecology e GeoEcoMar, Str. Dimitrie Onciul 23e25, Sector 2, 024053 Bucharest, Romania Razelm-Sinoe Lagoon System, situated in the NW part of the Black Sea, in tight connection with the Danube Delta, has been subject to major changes due to human interventions in the past century. These changes have resulted into a complete change of the Lagoon specific ecosystems compared to its pristine state. In its natural state, as brackish - transitional environment, Antipa (1894) mentions Razelm Lagoon as one of the places with the greatest fisheries around the Black Sea coast (about 1879 - 1884, there were approximately 10,000 fishermen, all working on the Razelm Sinoe Lagoon System). Starting with the end of the XIXth Century, new canals were dug and existing channels were dredged in order to develop tighter connections with the Danube River. The natural inlet of Portita was blocked four decades ago and connections between the various parts of the lagoon system were controlled by the building of locks and sluices. The 2 inlets of Sinoe Lagoon were also controlled during early 1980s. Under these conditions, the lagoon ecosystem changed from brackish towards freshwater, with major effects on the existing flora and fauna. The period of brutal interventions ended in 1989 and the Razelm-Sinoe Lagoon System became part of the Danube Delta Biosphere Reserve in 1991, with a strict policy of nature protection and restoration. Spatial planning has been the major management option for the entire reserve, lagoon system included. Plans for sustainable development of the Razelm-Sinoe Lagoon System have been built in a participative manner, involving the local stakeholders, as part of FP7 ARCH project. Special attention has been given to impacts of climate change. The study presents the vision for the development Razelm-Sinoe Lagoon System over

  6. Stormwater Characterization and Lagoon Sediment Analysis, Grand Forks Air Force Base, North Dakota

    DTIC Science & Technology

    1990-08-01

    tetrachloroethylene, and 0.0026 mg/l ethyl benzene. Analyses showed no pesticides . 4. Extraction Procedure (EP) Analysis. An AFOEHL contractor performed EP extraction ...runoff met North Dakota state stream standards. Lagoon sediment did not contain Extraction Procedure hazardous chemicals. Stormwater runoff exceeded...Standards for Water Quality for the State of North Dakota ( Extracts ) 39 D Site/Analysis Summary 69 E Lift Station Flow Records 73 F Wastewater

  7. Santa Margarita Lagoon Water Quality Monitoring Data

    DTIC Science & Technology

    2012-08-01

    sits entirely within the boundaries of Marine Corps Base Camp Pendleton. It forms up where the Santa Margarita River meets the Pacific Ocean just north...of Oceanside, California. The western boundary of the lagoon is the beach berm that borders the ocean . The estuarine lagoon is usually open to the... ocean through a limited section of berm, although there are occasions when the lagoon is effectively closed to exchange with the ocean . The eastern

  8. [Violence in social networks: an exploration of the online expressions of teens from marginalized areas of Greater Buenos Aires].

    PubMed

    Linne, Joaquín Walter; Angilletta, María Florencia

    2016-01-01

    This paper explores the online expressions of violence perpetrated or experienced by adolescents from marginalized areas of Greater Buenos Aires, Argentina. Using a qualitative methodology, four specific events were examined: threats, "bondis" [fights], cyberbullying and displays of mourning. To do so, 20 in-depth interviews and 3,000 virtual observations of profiles in the social network Facebook were carried out. Among the main results, it was seen that most expressions of violence are part of an offline-online dynamic. Empirical evidence is also offered based upon which it can be affirmed that the expressions of violence of these teenagers are developed around the culture of "aguante" [fierce loyalty]. The article ponders the extent to which, in the iconic platform of the option "like," these expressions are implicitly functional to the social network or, to the contrary, or whether they allow displacements and significant reappropriations on the part of users. New questions arise about the use of these tools by adolescents from marginalized areas and the need for more complex approaches to examine these phenomena.

  9. Nutritional status in parasitized and nonparasitized children from two districts of Buenos Aires, Argentina.

    PubMed

    Orden, Alicia B; Apezteguía, María C; Ciarmela, María L; Molina, Nora B; Pezzani, Betina C; Rosa, Diana; Minvielle, Marta C

    2014-01-01

    The Program for the Control of Intestinal Parasites and Nutrition was designed to intervene in small communities to prevent and control the effects of parasitic infections on children's health. To analyze the association between nutritional status and parasitic infection in suburban and rural children from Buenos Aires, Argentina. Nutritional status was assessed by anthropometric (weight, height, BMI, skinfolds, upper arm circumference, muscle, and fat upper arm areas) and biochemical (Hb, Ca, Mg, Zn, and Cu) indicators. Parasitological analysis were made on both serial stool and perianal swab samples. A total of 708 children aged 3-11 were measured. The biochemical analysis included 217 blood samples and the parasitological study included 284 samples. Anthropometric status was similar in both settings with low rates of underweight and stunting (<6%), and high rates of overweight (~17%) and obesity (~12%). Ca deficiency was significantly higher in suburban children where 80% of them were hypocalcemic. Around 70% of fecal samples contained parasites. Among infected children, the most prevalent species were Blastocystis hominis and Enterobius vermicularis (~43%) followed by Giardia lamblia (~17%). Differences in parasitological status between districts were not significant. In the suburban district parasitized children were lighter, shorter, and had a lower upper arm circumference than their non-infected peers. No differences in anthropometric status were seen among infected and uninfected rural children. The results suggest an association between intestinal parasites and physical growth in suburban children. Rural children seem to be protected against the effects of parasitic infection. Copyright © 2013 Wiley Periodicals, Inc.

  10. [HIV-1 resistance to antiretroviral drugs in pregnant women from Buenos Aires metropolitan area].

    PubMed

    Zapiola, Inés; Cecchini, Diego; Fernández Giuliano, Silvina; Martínez, Marina; Rodríguez, Claudia; Bouzas, María Belén

    The study aimed to determine the prevalence of antiretroviral resistance associated mutations in HIV-1 infected pregnant woman treated in Buenos Aires metropolitan area (period 2008-2014). A total of 136 women with viral load = 500 copies/ml were included: 77 (56.6%) were treatment-naïve and 59 (43.4%) were antiretroviral-experienced patients either with current (n: 24) or previous (n = 35) antiretroviral therapy. Genotypic baseline resistance was investigated in plasma of antiretroviral-naïve patients and antiretroviral-experienced patients. The resistance mutations were identified according to the lists of the World Health Organization and the International Antiviral Society, respectively. Frequencies of resistance associated mutations detected in 2008-2011 and 2012-2014 were compared. A total of 37 (27.2%) women presented at least one resistance associated mutation: 25/94 (26.5%) in 2008-2011 and 12/42 (28.5%) in 2012-2014 (p > 0.05). Among naïves, 15 (19.5%) had at least one mutation: 10/49 (20.4%) in the period 2008-2011 and 5/28 (17.8%) in 2012-2014 (p > 0.05). The resistance mutations detected in naïves were associated with non nucleoside reverse transcriptase inhibitors, being K103N the most common mutation in both periods. In antiretroviral experienced patients, 22/59 (37.3%) had at least one resistance mutation. This study demonstrates a high frequency of resistance associated mutations which remained stable in the period analyzed. These levels suggest an increased circulation of HIV-1 antiretroviral resistant strains in our setting compared to previous reports from Argentina.

  11. The effect of heat fluxes on ammonia emission from swine waste lagoon based on neural network analyses

    USDA-ARS?s Scientific Manuscript database

    Understanding factors that affect ammonia emissions from swine waste lagoons or any animal waste receptacles is a necessary first step in deploying potential remediation options. In this study, we examined the various meteorological factors (i.e., air temperatures, solar radiation, and heat fluxes)...

  12. Natural infection in Pampas fox (Lycalopex gymnocercus) by Lagochilascaris major Leiper, 1910 (Nematoda: Ascarididae) in Buenos Aires, Argentina.

    PubMed

    Scioscia, Nathalia Paula; Olmos, Leandro; Gorosábel, Antonella; Bernad, Lucía; Pedrana, Julieta; Denegri, Guillermo María

    2018-06-25

    Lagochilascariosis is an emerging parasitic disease limited to the American continent, caused by nematodes of the genus Lagochilascaris. Its life cycle is heteroxenous, involving natural definitive hosts (wild carnivores), accidental hosts (domestic carnivores and humans), and intermediate hosts (rodents). Here we report, for the first time, the occurrence of Lagochilascaris major in female of a Pampas fox (Lycalopex gymnocercus) which was found in the Mar Chiquita basin, Buenos Aires province, Argentina. At necropsy, multiple Lagochilascaris larvae and several adults (1 female and 5 male) were observed inserted in the mucosa of the trachea and a male was also collected in the stomach. The diagnosis was made by observing the different stages with optical microscopy, by scanning electron microscopy of adult males and coproparasitological analysis. Although cases of lagochilascariosis have been reported in wildlife in different countries of the American continent, in Argentina, cases are really rare and were only found in domestic cats. Graphical abstract ᅟLagochilascariosis is an emerging parasitic disease limited to the American continent. In Argentina, sporadic cases of Lagochilascariosis were reported in domestic cats but this work represents the first record in a wild carnivore (L. gymnocercus) naturally infected with L. major.

  13. Scottish saline lagoons: Impacts and challenges of climate change

    NASA Astrophysics Data System (ADS)

    Angus, Stewart

    2017-11-01

    The majority of Scotland's saline lagoons are located on the low-lying coastlines of the Western Isles and the northern archipelagos of Orkney and Shetland, where recorded annual relative sea level rise rates are among the highest in Scotland. The sediment-impounded lagoons of Orkney and Shetland will either lose their impoundment and become incorporated in marine coastal waters, or become increasingly saline, as relative sea levels rise. The rock-basin lagoons of the Western Isles will retain their restricted exchange with the sea but will also become more saline with rising sea level. Specialist lagoonal organisms tend to have wide salinity tolerances but may succumb to competition from marine counterparts. In all areas, there are sufficient fresh-water inland water bodies with potential to be captured as lagoons to compensate for loss of extent and number, but the specialist lagoon biota tend to have limited dispersal powers. It is thus possible that they will be unable to transfer to their analogue sites before existing lagoons become fully marine, giving conservation managers the problem of deciding on management options: leave natural processes to operate without interference, manage the saline inflow to maintain the current salinity regime, or translocate lagoon organisms perceived as threatened by rising salinities. Timing of conversion and capture is unpredictable due to local topography and complications caused by variable stratification.

  14. The effect of lagoons on Adriatic Sea tidal dynamics

    NASA Astrophysics Data System (ADS)

    Ferrarin, Christian; Maicu, Francesco; Umgiesser, Georg

    2017-11-01

    In this study the effects that lagoons exert on the barotropic tidal dynamics of a regional sea, the Adriatic Sea, were numerically explored. This semi-enclosed basin is one of the places with the highest tidal range in the Mediterranean Sea and is characterised by the presence of several lagoons in its northern part. The tidal dynamics of a system comprising the whole Adriatic Sea and the lagoons of Venice, Marano-Grado and Po Delta were investigated using an unstructured hydrodynamic model. Numerical experiments with and without lagoons reveal that even if the considered shallow water bodies represent only the 0.5 and 0.002% of the Adriatic Sea surface and volume, respectively, they significantly affect the entire Northern Adriatic Sea tidal dynamics by enhancing tidal range (by 5%) and currents (by 10%). The inclusion of lagoons in the computation improved the model performance by 25% in reproducing tidal constituents in the Adriatic Sea. The back-effect of the lagoons on the open-sea tide is due to the waves radiating from the co-oscillating lagoons into the adjacent sea. This is the first time these processes are shown to be relevant for the Adriatic Sea, thus enhancing the understanding of the tidal dynamics in this regional sea. These findings may also apply to other coastal seas with connections to lagoons, bays and estuaries.

  15. Comments on Environmental and Sanitary Aspects of the Scorpionism by Tityus trivittatus in Buenos Aires City, Argentina

    PubMed Central

    de Roodt, Adolfo Rafael

    2014-01-01

    Deaths by venomous animals are medical emergencies that can lead to death and thus constitute sanitary problems in some regions of the world. In the South of America, the accidents by these animals are a common sanitary problem especially in warm, tropical or subtropical regions, related with rural work in several countries. Argentina is located in the extreme South of South America and a minor part of the continental surface is in tropical or subtropical regions, where most of the accidents by venomous animals happen. However, in the big cities in the center and South of the country, with no relation to rural work, scorpionism, mostly due to the synanthropic and facultative parthenogenetic scorpion Tityus trivittatus, has become a sanitary problem in the last few decades. This scorpion is present in the biggest cities of Argentina and in the last decades has killed over 20 children in provinces of the center and north of the country, mostly in big cities. In addition, it seems that this species is growing and spreading in new regions of the cities. In this revision, some characteristics of this scorpion regarding its habitat, spreading in Buenos Aires city, combat measures and available treatments are discussed. PMID:24759176

  16. Nutrient-Chlorophyll Relationships in the Indian River Lagoon, Florida

    EPA Science Inventory

    The Indian River Lagoon is a highly diverse estuary located along Florida’s Atlantic coast. The system is made up of the main stem and two side-lagoons: the Banana River and Mosquito Lagoon. We segmented the main stem into three sections based on spatial trends in water quality ...

  17. [Body, disability, and stigma in the origins of the field of adapted sport in the city of Buenos Aires, 1950-1961: a mere interiorization of a devalued identity?].

    PubMed

    Ferrante, Carolina

    2014-01-01

    Although adapted sport is considered the main integrator of people with disabilities, Disability Studies argues that it reinforces the oppression suffered by this group. However, these positions do not historically reconstruct the ethos constructed in sport. In order to contribute to this discussion, I analyze here the ways of thinking about and experiencing disability that were constructed in the origins of the field of adapted sport, in the city of Buenos Aires, from 1950 to 1961. Thus, I begin by analyzing the content of publications of the first clubs for people with disabilities and in-depth interviews with protagonists of the origins of adapted sport and local physiatry.

  18. Magnetic Characterization of Stream-Sediments From Buenos Aires Province, Argentina, Affected by Pollution

    NASA Astrophysics Data System (ADS)

    Chaparro, M. A.; Sinito, A. M.; Bidegain, J. C.; Gogorza, C. S.; Jurado, S.

    2001-12-01

    A wide urban area from Northeast of Buenos Aires Province is exposed to an important anthropogenic influence, mainly due to industrial activity. In this two water streams were chosen: one of them (Del Gato stream, G) next to La Plata City and the another one (El Pescado stream, P) on the outskirts of the city. Both streams have similar characteristics, although the first one (G) has a higher input of pollutants (fluvial effluents, fly ashes, solid wastes, etc.) than the last one (P). Sediments analyzed in this work are limes from continental origin of PostPampeano (Holocene). Although, some cores were affected by sandy-limy sediments with mollusc valves from Querandino Sea (Pleistocene - later Holocene) and limy sediments of chestnut color with calcareous concretions from the Ensenadense. Magnetic measurements and geochemical studies were carried out on the samples. Among the magnetic parameters, specific susceptibility (X), X frequency-dependence (Xfd%), X temperature-dependence, Natural Remanent Magnetization (NRM), Isothermal Remanent Magnetization (IRM), Saturation IRM (SIRM), coercivity of remanence (Bcr), S ratio and SIRM/X ratio, Anhysteric Remanent Magnetization (ARM), Magnetic and Thermal Demagnetization were studied. The magnetic characteristics for both sites indicate the predominance of magnetically soft minerals on G site and relatively hard minerals on P site. Magnetite is the main magnetic carrier, Pseudo Single Domain and Single Domain grains were found. Chemical studies show (in some cases) a high concentration for some heavy metals (Pb, Cu, Zn, Ni and Fe) on the upper 22-cm. Contents of heavy metals and ARM were correlated. Very good correlation (R> 0.81) is found for Cu, Zn, Ni, Fe and the sum (of Pb, Cu, Zn and Ni), and a weaker correlation for Pb.

  19. Local and remote black carbon sources in the Metropolitan Area of Buenos Aires

    NASA Astrophysics Data System (ADS)

    Diaz Resquin, Melisa; Santágata, Daniela; Gallardo, Laura; Gómez, Darío; Rössler, Cristina; Dawidowski, Laura

    2018-06-01

    Equivalent black carbon (EBC) mass concentrations in the fine inhalable fraction of airborne particles (PM2.5) were determined using a 7-wavelength Aethalometer for 17 months, between November 2014 and March 2016, for a suburban location of the Metropolitan Area of Buenos Aires (MABA), Argentina. In addition to describing seasonal and diurnal black carbon (BC) cycles for the first time in this region, the relative contributions of fossil fuel and remote and local biomass burning were determined by distinguishing different carbonaceous components based on their effect on light attenuation for different wavelengths. Trajectory analyses and satellite-based fire products were used to illustrate the impact of long-range transport of particles emitted by non-local sources. EBC data showed a marked diurnal cycle, largely modulated by traffic variations and the height of the boundary layer, and a seasonal cycle with monthly median EBC concentrations (in μg /m3) ranging from 1.5 (February) to 3.4 (June). Maximum values were found during winter due to the combination of prevailingly stable atmospheric conditions and the increase of fossil fuel emissions, derived primarily from traffic and biomass burning from the domestic use of wood for heating. The use of charcoal grills was also detected and concentrated during weekends. The average contribution of fossil fuel combustion sources to EBC concentrations was 96%, with the remaining 4% corresponding to local and regional biomass burning. During the entire study period, only two events were identified during which EBC concentrations attributed to regional biomass burning accounted for over 50% of total EBC ; these events demonstrate the relevance of agricultural and forestry activities that take place far from the city yet whose emissions can affect the urban atmosphere of the MABA.

  20. Benthic ecology of tropical coastal lagoons: Environmental changes over the last decades in the Términos Lagoon, Mexico

    NASA Astrophysics Data System (ADS)

    Grenz, Christian; Fichez, Renaud; Silva, Carlos Álvarez; Benítez, Laura Calva; Conan, Pascal; Esparza, Adolfo Contreras Ruiz; Denis, Lionel; Ruiz, Silvia Díaz; Douillet, Pascal; Martinez, Margarita E. Gallegos; Ghiglione, Jean-François; Mendieta, Francisco José Gutiérrez; Origel-Moreno, Montserrat; Garcia, Antonio Zoilo Marquez; Caravaca, Alain Muñoz; Pujo-Pay, Mireille; Alvarado, Rocío Torres; Zavala-Hidalgo, Jorge

    2017-10-01

    The Términos Lagoon is a 2000-km2 wide coastal lagoon linked to the largest river catchment in Mesoamerica. Economic development, together with its ecological importance, led the Mexican government to pronounce the Términos Lagoon and its surrounding wetlands as a Federal protected area for flora and fauna in 1994. It is characterized by small temperature fluctuations, but with two distinct seasons (wet and dry) that control the biological, geochemical, and physical processes and components. This paper presents a review of the available information about the Términos Lagoon. The review shows that the diversity of benthic communities is structured by the balance between marine and riverine inputs and that this structuration strongly influences the benthic metabolism and its coupling with the biogeochemistry of the water column. The paper also presents many specific drivers and recommendations for a long-term environmental survey strategy in the context of the expected Global Change in the Central American region.

  1. Both riverine detritus and dissolved nutrients drive lagoon fisheries

    NASA Astrophysics Data System (ADS)

    Bonthu, Subbareddy; Ganguly, Dipnarayan; Ramachandran, Purvaja; Ramachandran, Ramesh; Pattnaik, Ajit K.; Wolanski, Eric

    2016-12-01

    The net ecosystem metabolism in lagoons has often been estimated from the net budget of dissolved nutrients. Such is the case of the LOICZ estuarine biogeochemistry nutrient budget model that considers riverine dissolved nutrients, but not riverine detritus. However the neglect of detritus can lead to inconsistencies; for instance, it results in an estimate of 5-10 times more seaward export of nutrients than there is import from rivers in Chilika Lagoon, India. To resolve that discrepancy the UNESCO estuarine ecohydrology model, that considers both dissolved nutrients and detritus, was used and, for Chilika Lagoon, it reproduced successfully the spatial distribution of salinity, dissolved nutrients, phytoplankton and zooplankton as well as the fish yield data. Thus the model suggests that the riverine input of both detritus and dissolved nutrients supports the pelagic food web. The model also reproduces well the observation of decreased fish yield when the mouth of the lagoon was choked in the 1990s, demonstrating the importance of the physics that determine the flushing rate of waterborne matter. Thus, both farming in the watershed by driving the nutrient and detritus inputs to the lagoon, and dredging and engineering management of the mouth by controlling the flushing rate of the lagoon, have a major influence on fish stocks in the lagoon.

  2. Fish fauna recovery in a newly re-flooded Mediterranean coastal lagoon

    NASA Astrophysics Data System (ADS)

    Koutrakis, Emmanuil; Sylaios, Georgios; Kamidis, Nikolaos; Markou, Dimitrios; Sapounidis, Argyris

    2009-08-01

    Drana Lagoon, located at the NW site of Evros River Delta, was drained in 1987 and re-flooded in 2004 within the framework of an integrated wetland restoration project. This study presents the results of a monitoring program of the lagoon's oceanographic, water quality and fish fauna characteristics, during the pre- and post-restoration period. Results depict the presence of high salinity water (up to 41) due to seawater intrusion, strong evaporation in its interior and inadequate freshwater inflows. Overall, nutrient levels were low depicting local changes. Tidal variability at the mouth was approximately 0.2 m, producing high velocity tidal currents (up to 0.75 m/s). Eleven fish fauna species were collected; seven species were caught in both the inlet channel and the lagoon during the pre-restoration period and nine species in the post-restoration period. Atherina boyeri (37.6%) and Pomatoschistus marmoratus (31.7%) dominated the lagoon during the post-restoration period. Most of the A. boyeri specimens (88.5%) were caught inside the lagoon, while P. marmoratus had an almost equal distribution in the inlet channel and the lagoon (56.3% and 43.7% respectively). The presence of species of the Mugilidae family (5.2% total average catches after lagoon re-flooding) was mainly in the inlet channel (12.6% of the average catches) and not inside the lagoon (only 1.3% of the average catches). The small number of fish species inhabiting the lagoon might be the result of the recent restoration or it could be related with the increased water flow observed at the lagoon mouth during the flood and ebb tidal phases, and also in the presence of a smooth bank in the concrete waterspout that connects the entrance channel with the lagoon. The limited presence of the Mugilidae juveniles inside the lagoon could be related to the prevailing tidal inlet dynamics (i.e. strong ebb flow at lagoon inlet), thus preventing the species to enter the lagoon. In order to restore the lagoon

  3. Meeting Report of the XIV International Small Bowel Transplant Symposium: Summary of Presentations, Workshops, and Debates From a Comprehensive Meeting on Intestinal Failure, Rehabilitation, and Transplantation, Buenos Aires, Argentina, June 10-13, 2015.

    PubMed

    Gondolesi, Gabriel E; Fernandez, Adriana; Burghardt, Karolina M; Nowakowski, Scott; Kaufman, Stuart S; Pascher, Andreas; Florescu, Diana; Ruiz, Phillip; Vianna, Rodrigo; Clarke, Sara; Oltean, Mihai; Rumbo, Martin; Mazariegos, George; Sudan, Debra L; Farmer, Douglas G

    2017-04-01

    The 2015 meeting of the Intestinal Transplant Association was held in Buenos Aires, Argentina. This was the 14th International Small Bowel Transplant Symposium, and it was the first meeting organized as a joint venture of the Transplantation Society, the Intestinal Transplant Association, and the Argentinean Transplant Society (Sociedad Argentina de Trasplantes). Innovative aspects of the classic meeting format included workshops sessions, debates, and multicenter studies. This report highlights the most prominent scientific contributions and results of the first such symposium in a Latin American country.

  4. Nutrient removal from swine lagoon effluent by duckweed

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bergmann, B.A.; Cheng, J.; Classen, J.

    2000-04-01

    Three duckweed geographic isolates were grown on varying concentrations of swine lagoon effluent in a greenhouse to determine their ability to remove nutrients from the effluent. Duckweed biomass was harvested every other day over a 12-day period. Duckweed biomass production, nutrient loss from the swine lagoon effluent, and nutrient content of duckweed biomass were used to identify effluent concentrations/geographic isolate combinations that are effective in terms of nutrient utilization from swine lagoon effluent and production of healthy duckweed biomass. When Lemna minor geographic isolate 8627 was grown on 50% swine lagoon effluent, respective losses of TKN, NH{sub 3}-N, TP, OPO{submore » 4}-P, TOC, K, Cu, and Zn were 83, 100, 49, 31, 68, 21, 28 and 67%.« less

  5. Accuracy of lagoon gas emissions using an inverse dispersion method

    USDA-ARS?s Scientific Manuscript database

    Measuring gas emissions from treatment lagoons and storage ponds poses challenging conditions for existing micrometeorological techniques because of non-ideal wind conditions. These include those induced by trees and crops surrounding the lagoons, and lagoons with dimensions too small to establish ...

  6. Mosquito Lagoon environmental resources inventory

    NASA Technical Reports Server (NTRS)

    Provancha, Jane A.; Hall, Carlton R.; Oddy, Donna M.

    1992-01-01

    This document provides a synopsis of biotic and abiotic data collected in the Mosquito Lagoon area in relation to water quality. A holistic ecological approach was used in this review to allow for summaries of climate, land use, vegetation, geohydrology, water quality, fishes, sea turtles, wading birds, marine mammals, invertebrates, shellfish, and mosquito control. The document includes a bibliographic database list of 157 citations that have references to the Mosquito Lagoon, many of which were utilized in development of the text.

  7. Sediment budget in the Lagoon of Venice, Italy

    NASA Astrophysics Data System (ADS)

    Sarretta, A.; Pillon, S.; Molinaroli, E.; Guerzoni, S.; Fontolan, G.

    2010-05-01

    A comparison of 1927, 1970 and 2002 bathymetric surveys in the Lagoon of Venice was used to reconstruct historical changes in sedimentation. A detailed GIS-based analysis of the charts revealed the timing and pattern of geomorphic changes and allowed calculation of sediment deposition and erosion for the entire lagoon and each of its four sub-basins: Treporti, Lido, Malamocco and Chioggia. Two main developments are discernible from comparative observation of the areal distribution of the main elevation ranges: the diminution in area of the saltmarshes, which decreased by more than 50%, from 68 km 2 in 1927 to 32 km 2 in 2002, and the progressive deepening of the lagoon, with a huge increase in the area of subtidal flats (between -0.75 and -2.00 m depth), from 88 to 206 km 2 during the same period. Generally, the lagoon showed a clear-cut change in the most frequent depths (modal depth) from a value of -0.62 m in 1927 to -0.88 m in 2002. The deepening of the lagoon affected mostly the lagoonal sub-basins south of the town of Venice, where modal depth increased from -0.65 to -1.12 m in Lido, from -0.64 to -1.75 m in Malamocco and from -0.39 to -0.88 m in Chioggia. Large changes in lagoonal morphology were caused by human-induced subsidence, the dredging of navigation channels between 1927 and 1970, and intense natural erosion enhanced by sediment re-suspension due to Manila clam fishing between 1970 and 2002. There was a net loss of about 110 Mm 3 of sediment from the lagoon, most of which (73 Mm 3, ca.70%) was in the earlier period. A significant amount was lost by dredging and direct disposal outside the system, either on land or at sea, and there was a net loss of 39 Mm 3 from the lagoon to the sea through the inlets, at an annual rate of 0.5 Mm 3. Comparison of erosion rates in the two periods revealed an alarming acceleration, from a net sediment loss of 0.3 Mm 3 yr -1 in the period 1927-1970 to 0.8 Mm 3 yr -1 in 1970-2002. Deterioration caused a shift from a

  8. [Prevention of cervical and breast cancer in health services and non-governmental organizations in the city of Buenos Aires].

    PubMed

    Ponce, Marisa

    2013-08-01

    The article analyzes actions for the prevention of cervical and breast cancer in public, private, and employment-based health services and in non-governmental organizations in the city of Buenos Aires. The article seeks to reflect on the reach and limitations of the approaches implemented in the three subsectors of the health care system and the community to prevent women from suffering or eventually dying as a consequence of these diseases, in the fragmented context of a health system with great heterogeneity in access and deep social inequalities in the use of preventive actions. The study utilizes a broad definition of prevention which integrates education, awareness-building and early detection of pre-carcinogenic and carcinogenic lesions, among other medical and non-medical components. The results were obtained using semi-structured interviews with subjects from public hospitals, employment-based health care services, private medical companies and non-governmental organizations with work in cancer prevention. These results show that contrary to a comprehensive approach, each institution limits its actions to only one aspect of prevention, implementing predominately isolated or disconnected actions inadequate to generate an autonomous and well-informed demand for treatment and health care among women.

  9. Pedro Gutierrez Bueno's Textbooks: Audiences, Teaching Practices and Chemical Revolution

    ERIC Educational Resources Information Center

    Sanchez, Jose Ramon Bertomeu; Belmar, Antonio Garcia

    2006-01-01

    Pedro Gutierrez Bueno wrote two editions of a chemistry textbook between 1788 and 1802. The paper offers a comparative view of both editions taking into account Gutierrez Bueno's biography, his intended audience and the changes related to the so-called chemical revolution. Some conclusions are at odds with common images about scientific…

  10. Metagenomes of Mediterranean Coastal Lagoons

    PubMed Central

    Ghai, Rohit; Hernandez, Claudia Mella; Picazo, Antonio; Mizuno, Carolina Megumi; Ininbergs, Karolina; Díez, Beatriz; Valas, Ruben; DuPont, Christopher L.; McMahon, Katherine D.; Camacho, Antonio; Rodriguez-Valera, Francisco

    2012-01-01

    Coastal lagoons, both hypersaline and freshwater, are common, but still understudied ecosystems. We describe, for the first time, using high throughput sequencing, the extant microbiota of two large and representative Mediterranean coastal lagoons, the hypersaline Mar Menor, and the freshwater Albufera de Valencia, both located on the south eastern coast of Spain. We show there are considerable differences in the microbiota of both lagoons, in comparison to other marine and freshwater habitats. Importantly, a novel uncultured sulfur oxidizing Alphaproteobacteria was found to dominate bacterioplankton in the hypersaline Mar Menor. Also, in the latter prokaryotic cyanobacteria were almost exclusively comprised by Synechococcus and no Prochlorococcus was found. Remarkably, the microbial community in the freshwaters of the hypertrophic Albufera was completely in contrast to known freshwater systems, in that there was a near absence of well known and cosmopolitan groups of ultramicrobacteria namely Low GC Actinobacteria and the LD12 lineage of Alphaproteobacteria. PMID:22778901

  11. Benthic Primary Production Budget of a Caribbean Reef Lagoon (Puerto Morelos, Mexico)

    PubMed Central

    Naumann, Malik S.; Jantzen, Carin; Haas, Andreas F.; Iglesias-Prieto, Roberto; Wild, Christian

    2013-01-01

    High photosynthetic benthic primary production (P) represents a key ecosystem service provided by tropical coral reef systems. However, benthic P budgets of specific ecosystem compartments such as macrophyte-dominated reef lagoons are still scarce. To address this, we quantified individual and lagoon-wide net (Pn) and gross (Pg) primary production by all dominant functional groups of benthic primary producers in a typical macrophyte-dominated Caribbean reef lagoon near Puerto Morelos (Mexico) via measurement of O2 fluxes in incubation experiments. The photosynthetically active 3D lagoon surface area was quantified using conversion factors to allow extrapolation to lagoon-wide P budgets. Findings revealed that lagoon 2D benthic cover was primarily composed of sand-associated microphytobenthos (40%), seagrasses (29%) and macroalgae (27%), while seagrasses dominated the lagoon 3D surface area (84%). Individual Pg was highest for macroalgae and scleractinian corals (87 and 86 mmol O2 m−2 specimen area d−1, respectively), however seagrasses contributed highest (59%) to the lagoon-wide Pg. Macroalgae exhibited highest individual Pn rates, but seagrasses generated the largest fraction (51%) of lagoon-wide Pn. Individual R was highest for scleractinian corals and macroalgae, whereas seagrasses again provided the major lagoon-wide share (68%). These findings characterise the investigated lagoon as a net autotrophic coral reef ecosystem compartment revealing similar P compared to other macrophyte-dominated coastal environments such as seagrass meadows and macroalgae beds. Further, high lagoon-wide P (Pg: 488 and Pn: 181 mmol O2 m−2 lagoon area d−1) and overall Pg:R (1.6) indicate substantial benthic excess production within the Puerto Morelos reef lagoon and suggest the export of newly synthesised organic matter to surrounding ecosystems. PMID:24367570

  12. Neural network analysis on the effect of heat fluxes on greenhouse gas emissions from anaerobic swine waste treatment lagoon

    USDA-ARS?s Scientific Manuscript database

    In this study, we examined the various meteorological factors (i.e., air temperatures, solar radiation, and heat fluxes) that potentially affect greenhouse gas (GHG) emissions from swine waste lagoon. GHG concentrations (methane, carbon dioxide, and nitrous oxide) were monitored using a photoacous...

  13. Lockport Sewage Lagoon.

    ERIC Educational Resources Information Center

    Perry, John

    1995-01-01

    Describes a student initiated stewardship project that resulted in the transformation of a sewage lagoon near the school into a place to study nature. Contains a list of 20 things that discourage a successful stewardship project. (LZ)

  14. Autonomous mobile platform for monitoring air emissions from industrial and municipal wastewater ponds.

    PubMed

    Fu, Long; Huda, Quamrul; Yang, Zheng; Zhang, Lucas; Hashisho, Zaher

    2017-11-01

    Significant amounts of volatile organic compounds and greenhouse gases are generated from wastewater lagoons and tailings ponds in Alberta, Canada. Accurate measurements of these air pollutants and greenhouse gases are needed to support management and regulatory decisions. A mobile platform was developed to measure air emissions from tailings pond in the oil sands region of Alberta. The mobile platform was tested in 2015 in a municipal wastewater treatment lagoon. With a flux chamber and a CO 2 /CH 4 sensor on board, the mobile platform was able to measure CO 2 and CH 4 emissions over two days at two different locations in the pond. Flux emission rates of CO 2 and CH 4 that were measured over the study period suggest the presence of aerobic and anaerobic zones in the wastewater treatment lagoon. The study demonstrated the capabilities of the mobile platform in measuring fugitive air emissions and identified the potential for the applications in air and water quality monitoring programs. The Mobile Platform demonstrated in this study has the ability to measure greenhouse gas (GHG) emissions from fugitive sources such as municipal wastewater lagoons. This technology can be used to measure emission fluxes from tailings ponds with better detection of spatial and temporal variations of fugitive emissions. Additional air and water sampling equipment could be added to the mobile platform for a broad range of air and water quality studies in the oil sands region of Alberta.

  15. Association between dietary habits, education, serum triglycerides and blood cholesterol among women of Cabildo, Buenos Aires.

    PubMed

    Schneider, Raul J; Barengo, Noel; Haapala, Irja; Tavella, Marcelo

    2006-01-01

    A cross sectional study of 107 women between 20 and 69 years old, living in the town of Cabildo, province of Buenos Aires, Argentina, which describes food intake and analyses its relation to their education, blood cholesterol and serum triglyceride levels. A food frequency questionnaire including questions regarding meal patterns and food use were completed by the participants. Questions regarding educational status were included. A nutritional risk score was created from nine food groups. Total blood cholesterol and serum triglyceride levels were determined. Average total blood cholesterol levels of the women who participated in the present study were higher (209 mg/dl) than those recommended by the National Cholesterol Education Program, while triglyceride values remained within the normal range (124 mg/dl). Total blood cholesterol levels increased with age. Bread, biscuits and cakes were consumed on a daily basis by 98% of the participants and dairy products by 92%, these being mainly full-fat. Meat and fast food intake were very high (96% and 100% respectively). Vegetable and fish intakes were higher among the more educated women. Mayonnaise (58%) and butter (43%) are popular as food dressings and bread spreads respectively, and sunflower oil was the most commonly used for cooking by 94% of the participants. Women with low educational levels (less than 7 years) had higher nutritional risk scores, and thus unhealthier dietary habits than those with more years of formal education. No statistically significant association was found between food groups and cholesterol or triglyceride levels.

  16. Nutrient-Chlorophyll Relationships in the Indian River Lagoon, Florida(SEERS)

    EPA Science Inventory

    The Indian River Lagoon is a highly diverse estuary located along Florida’s Atlantic coast. The system is made up of the main stem and two side-lagoons: the Banana River and Mosquito Lagoon. We segmented the main stem into three sections based on spatial trends in water quality ...

  17. Is the Venice Lagoon Noisy? First Passive Listening Monitoring of the Venice Lagoon: Possible Effects on the Typical Fish Community.

    PubMed

    Bolgan, Marta; Picciulin, Marta; Codarin, Antonio; Fiorin, Riccardo; Zucchetta, Matteo; Malavasi, Stefano

    2016-01-01

    Three passive listening surveys have been carried out in two of the three Venice lagoon tide inlets and inside the Venice island. The spectral content and the intensity level of the underwater noise as well as the presence or absence of Sciaena umbra and the distribution of its different sound patterns have been investigated in all the recording sites. The passive listening proved to be successful in detecting S. umbra drumming sounds in both Venice lagoon tide inlets. Our results indicate that the spectral content and the level of underwater noise pollution in the Venice lagoon could affect fish acoustic communication.

  18. Prevalence of molar-incisor hypomineralization (MIH) in children seeking dental care at the Schools of Dentistry of the University of Buenos Aires (Argentina) and University of la Republica (Uruguay).

    PubMed

    Biondi, Ana M; López Jordi, María del C; Cortese, Silvina G; Alvarez, Licet; Salveraglio, Inés; Ortolani, Andrea M

    2012-01-01

    The objectives of this study are to compare the prevalence of MIH in children seeking dental care spontaneously at the Department of Comprehensive Children's Dentistry of the University of Buenos Aires (UBA) and Department of Pediatric Dentistry of the University of La República (UdelaR) and to analyze the distribution according to year of birth, sex, age, number of affected teeth and maximum degree of severity in molars and incisors. During 2010, nine pediatric dentists from both schools (Kappa = 0.94) assessed all children born between 1993 and 2003 whose 4 first molars and 8 permanent incisors had erupted. Specially designed charts were used to record sex, year of birth, institution, presence of MIH, number of affected incisors and molars and maximum degree of severity for each tooth. Two groups were formed: UBA: A (n = 512) and UdelaR: B (n = 463). 975 children (11.6 +/- 2.67 years) were evaluated. The prevalence of MIH in the total sample was 6.56%, without significant differences between A and B (p = 0.76). There was no significant difference between groups regarding age (p = 0. 95) or sex (p = 0.30). A significant increase was found in both institutions according to year of birth during the study period. (A: p = 0.0017) B: p = 0. 0058). The results of this study show a similar prevalence of MIH among patients seeking dental care at the Schools of Dentistry of the University of Buenos Aires (Argentina) and University of la República (Uruguay). No significant difference was found comparing the distribution by sex, affected teeth or severity of each tooth. A highly significant positive correlation was found regarding the year of birth. The relevance of MIH as an emerging pathology requires studies on larger samples covering the entire countries.

  19. [Food and health risks: views on healthy food and food consumption practices among middle-class women and men in the Metropolitan Area of Buenos Aires].

    PubMed

    Freidin, Betina

    2016-01-01

    In this article we analyze notions about healthy food and the perceptions of risks related to industrialized foodstuffs within a group of young and middle-aged females and males who belong to the middle class and live in the Metropolitan Area of Buenos Aires. Data come from eight focus groups that were carried out in 2013. The study shows that the participants of the focus group have incorporated scientific-nutritional knowledge into their conceptions of healthy food. However, few discuss the risks of industrialized food beyond the growing public attention regarding trans fats and salt content. Although organic foods are positively valued, participants object to their high cost and the location of their commercialization. We show how in their food practices, the participants of the focus groups weigh their concern about health against other priorities such as costs, convenience, aesthetics, pleasure and sociability.

  20. Hydrogeochemical and isotopic characterisation of groundwater in a sand-dune phreatic aquifer on the northeastern coast of the province of Buenos Aires, Argentina.

    PubMed

    Carretero, Silvina C; Dapeña, Cristina; Kruse, Eduardo E

    2013-01-01

    This contribution presents the hydrochemical and isotopic characterisation of the phreatic aquifer located in the Partido de la Costa, province of Buenos Aires, Argentina. In the sand-dune barrier geomorphological environment, groundwater is mainly a low-salinity Ca-HCO3 and Na-HCO3-type, being in general suitable for drinking, whereas in the continental plain (silty clay sediments), groundwater is a Na-Cl type with high salinity and unsuitable for human consumption. The general isotopic composition of the area ranges from-6.8 to-4.3 ‰ for δ(18)O and from-39 to-21 ‰ for δ(2)H, showing that rainwater rapidly infiltrates into the sandy substrate and reaches the water table almost without significant modification in its isotopic composition. These analyses, combined with other chemical parameters, made it possible to corroborate that in the eastern area of the phreatic aquifer, there is no contamination from marine salt water.

  1. Environmental enhancement of swine lagoons through influent treatment

    USDA-ARS?s Scientific Manuscript database

    Confined swine production generates large volumes of wastewater typically stored and treated in anaerobic lagoons. Failure of these lagoons during tropical storms in North Carolina along with major public environmental concerns led to a permanent state moratorium of construction of new anaerobic lag...

  2. Mercury methylation and demethylation in Hg-contaminated lagoon sediments (Marano and Grado Lagoon, Italy)

    NASA Astrophysics Data System (ADS)

    Hines, Mark E.; Poitras, Erin N.; Covelli, Stefano; Faganeli, Jadran; Emili, Andrea; Žižek, Suzana; Horvat, Milena

    2012-11-01

    Mercury (Hg) transformation activities and sulfate (SO42-) reduction were studied in sediments of the Marano and Grado Lagoons in the Northern Adriatic Sea region as part of the "MIRACLE" project. The lagoons, which are sites of clam (Tapes philippinarum) farming, have been receiving excess Hg from the Isonzo River for centuries. Marano Lagoon is also contaminated from a chlor-alkali plant. Radiotracer methods were used to measure mercury methylation (230Hg, 197Hg), methylmercury (MeHg) demethylation (14C-MeHg) and SO42- reduction (35S) in sediment cores collected in autumn, winter and summer. Mercury methylation rate constants ranged from near zero to 0.054 day-1, generally decreased with depth, and were highest in summer. Demethylation rate constants were much higher than methylation reaching values of ˜0.6 day-1 in summer. Demethylation occurred via the oxidative pathway, except in winter when the reductive pathway increased in importance in surficial sediments. Sulfate reduction was also most active in summer (up to 1600 nmol mL-1 day-1) and depth profiles reflected seasonally changing redox conditions near the surface. Methylation and demethylation rate constants correlated positively with SO42- reduction and pore-water Hg concentrations, and inversely with Hg sediment-water partition coefficients indicating the importance of SO42- reduction and Hg dissolution on Hg cycling. Hg transformation rates were calculated using rate constants and concentrations of Hg species. In laboratory experiments, methylation was inhibited by amendments of the SO42--reduction inhibitor molybdate and by nitrate. Lagoon sediments displayed a dynamic seasonal cycle in which Hg dissolution in spring/summer stimulated Hg methylation, which was followed by a net loss of MeHg in autumn from demethylation. Sulfate-reducing bacteria (SRB) tended to be responsible for methylation of Hg and the oxidative demethylation of MeHg. However, during winter in surficial sediments, iron

  3. Spring and Summer Proliferation of Floating Macroalgae in a Mediterranean Coastal Lagoon (Tancada Lagoon, Ebro Delta, NE Spain)

    NASA Astrophysics Data System (ADS)

    Menéndez, M.; Comín, F. A.

    2000-08-01

    During the last 10 years, a drastic change in the structure of the community of primary producers has been observed in Tancada Lagoon (Ebro Delta, NE Spain). This consisted of a decrease in the abundance of submerged rooted macrophyte cover and a spring and summer increase in floating macroalgae. Two spatial patterns have been observed. In the west part of the lagoon, Chaetomorpha linum Kützing, dominated during winter and decreased progressively in spring when Cladophora sp. reached its maximum development. In the east part of the lagoon, higher macroalgal diversity was observed, together with lower cover in winter and early spring. Cladophora sp., Gracilaria verrucosa Papenfuss and Chondria tenuissima Agardh, increased cover and biomass in summer. Maximum photosynthetic production was observed in spring for G. verrucosa (10·9 mg O 2 g -1 DW h -1) and C. tenuissima (19·0 mg O 2 g -1 DW h -1) in contrast with Cladophora sp. (15·9 mg O 2 g -1 DW h -1) and Chaetomorpha linum (7·2 mg O 2 g -1 DW h -1) which reached maximum production in summer. Increased conductivity from reduced freshwater inflow, and higher water temperatures during periods of lagoon isolation, mainly in summer, were the main physical factors associated with an increase in floating macroalgal biomass across the lagoon. Reduced nitrogen availability and temperature-related changes in carbon availability during summer were related to a decrease in abundance of C. linum and increases in G. verrucosa and Cladophora sp.

  4. Submarine groundwater discharge into typical tropical lagoons: A case study in eastern Hainan Island, China

    NASA Astrophysics Data System (ADS)

    Wang, Xilong; Du, Jinzhou

    2016-11-01

    Assessing submarine groundwater discharge (SGD) into lagoons and bays can be helpful to understand biogeochemical processes, especially nutrient dynamics. In the present paper, radium (Ra) isotopes were used to quantify SGD in two typical tropical lagoons (Laoye Lagoon (LY Lagoon) and Xiaohai Lagoon (XH Lagoon)) of eastern Hainan Island, China. The Ra mass balance model provided evidence that SGD plays an important role in the hydrology of the LY Lagoon and the XH Lagoon, delivering average SGD fluxes of 1.7 × 106 (94 L m-2 d-1) and 1.8 × 106 (41 L m-2 d-1) m3 d-1, respectively. Tidal pumping was one of the important driving forces for SGD fluxes in the LY and the XH Lagoons. Tidal-driven SGD into the tidal channels of both lagoons can account for approximately 10% of the total SGD flux into the lagoons. In addition, the dissolved inorganic nutrient budgets were reassessed in the LY Lagoon and the XH Lagoon, which showed that SGD was the major source of nutrients entering the LY Lagoon and that the LY Lagoon behaved as a source for dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) and as a sink for dissolved silicate (DSi). Nutrient loads in the XH Lagoon were mainly derived from riverine inputs and SGD, and the XH Lagoon behaved as a source for DIP, but a sink for DIN and DSi.

  5. Geochemical Assessment of Groundwater in the Peri-urban Environment of Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Gallardo, A.

    2014-12-01

    Groundwater pollution is a major concern in peri-urban environments. Thus, water quality is being investigated at several domestic wells in Brandsen, 70 km south of Buenos Aires, Argentina. To present, about 20 water sources were sampled in orchards and small farms of the area. There is limited data about the wells construction, although collected information suggests that groundwater is derived from the superficial sandy loams of the Pampean Aquifer. Samples were analysed for major inorganic elements using ion chromatography and ICP-MS. Titration was used to estimate alkalinity. Physical characteristics (EC, pH, temperature) were measured on site. Results show that groundwater pH ranges from 6.5 to 7.8, with a specific conductance of 180 to 255 mS/m. A peak of 360 mS/m in one horticultural parcel is associated to local NO3- concentrations up to 140 mg/L. This value exceeds the maximum recommendations set by the WHO (50 mg/L). Considering that fertilizer inputs in that property are negligible, the high levels of NO3- might be attributed to effluents from a neighbour septic tank. An increase in NO3- (>150mg/L) was also detected in two conventional farms. This increase correlates to elevated SO42- concentrations (>300 mg/L) suggesting thus, fertilizers percolation into the saturated zone. The leaching of these fluids might be exacerbated by irrigation during new planting, and accumulations of fertilizer-solids in the root zones from previous seasons. Chloride concentrations average ~90 mg/L and would not pose a threat to health at the moment. Its main origin would be related to connate waters in the loam matrix, although some anthropogenic inputs might occur in the previously described farms. In general, the rest of the analysed elements fall within acceptable levels for drinking purposes as well. Nevertheless, further work is still necessary to better define the fate of the potential harmful elements and assess seasonal variations in water quality.

  6. Initial crop growth in soil collected from a closed animal waste lagoon.

    PubMed

    Zhu, L; Kirkham, M B

    2003-03-01

    In the 21st century, remediation of the soil beneath animal waste lagoons will become an important issue, as they are closed due to environmental regulations or to abandonment. The possibility of growing crops in the soil, which has high concentrations of ammonium-N, has not been studied. The objective of this experiment was to determine if crop species would germinate and grow in lagoon soil. Soil was gathered from a lagoon that had received wastes from swine (Sus scrofa) and beef (Bos taurus) since 1968. Eight crops were grown in greenhouse pots containing the lagoon soil: winter barley (Hordeum vulgare L. 'Weskan'); field corn (Zea mays L., Cargill's hybrid 7997); 'Plainsman' winter rapeseed [Brassica napus L. spp. oleifera (Metzg.) Sinsk. f. biennis]; soybean [Glycine max (L.) Merr. 'KS 4694'); forage sorghum [Sorghum bicolor (L.) Moench 'Norkan']; sunflower (Helianthus annuus L. 'Hysun 354'); and winter wheat (Triticum aestivum L.)--two cultivars: '2137' and 'Turkey.' Plants were grown for 35 days in lagoon soil or an agricultural soil (Haynie very fine sandy loam; coarse-silty, mixed, superactive, calcareous, mesic Mollic Udifluvent) obtained from a field near the closed lagoon. Ammonium-N (average value of 692 mg/kg) was about 70-85 times greater than the average value of 8-10 mg/kg NH4-N in Kansan soils. The lagoon soil was nonsodic and had a salinity ranking of "medium" with an electrical conductivity averaging 2.29 dS/m. The high ammonium-N concentration in the lagoon soil was not inhibitory to emergence and growth. The eight crops grew taller in the lagoon soil than in the agricultural soil. Except for '2137' wheat, dry weight was higher in the lagoon soil than in the agricultural soil. The results showed that the lagoon soil is not detrimental to early growth of eight crops.

  7. The glacial geomorphology of the Lago Buenos Aires and Lago Puerreydón ice lobes, Central Patagonia

    NASA Astrophysics Data System (ADS)

    Bendle, Jacob; Thorndycraft, Varyl; Palmer, Adrian

    2016-04-01

    Patagonia is ideally located for reconstructions of late Quaternary ice-climate interaction(s) in the Southern Hemisphere mid-latitudes, yet many questions remain concerning post-LGM ice sheet retreat dynamics across the region. While modern-day glaciation is restricted to three small icefields (the North and South Patagonian and Cordillera Darwin icefields), during the Quaternary, and at the LGM, episodes of significant ice advance culminated in an expansive Patagonian ice sheet (PIS) centered over the southern Andes, for which a long and well-preserved landform record exists. Previous mapping in the region has either aimed to achieve regional coverage, necessarily omitting more subtle/complex features suggestive of certain ice-marginal processes, or has focused on the identification of palaeo-ice limits (e.g. moraine ridges) for geochronological applications, with little attention given to other (e.g. glaciofluvial, glaciolacustrine) features that are significant for understanding post-LGM ice sheet retreat dynamics. This poster presents a comprehensive and highly detailed (<30m spatial resolution) map of the glacial geomorphology of the Lago Buenos Aires (46.4°S) and Lago Puerreydón (47.2°S) ice lobes, major outlet glaciers of the central sector of the former PIS. The map allows refined reconstructions of glacial and, in particular, deglacial ice-marginal processes, and will underpin further analysis on the retreat history of the palaeo-ice lobes using high-resolution lithostratigraphic (varve) analyses.

  8. Overview of ecotoxicological studies performed in the Venice Lagoon (Italy).

    PubMed

    Losso, C; Ghirardini, A Volpi

    2010-01-01

    This work reports on the state of the art of the bioindicators used to assess environmental quality (regarding chemical pollutant impacts) in the Venice lagoon. After a brief description of the roles, advantages and limitations of bioindicators in marine and transitional environments and a summary of the Venice lagoon characteristics, the ecotoxicological methods used during scientific studies and research projects in the Lagoon are reported. Since not all data are available and no database can be formulated, the main evidence from toxicity bioassays, biomarkers and bioaccumulation analyses since the end of the 1970s is spatially synthesized using maps and discussed according to the four Venice lagoon basins. The majority of indicators showed that the Lido basin (north-central lagoon), affected by the presence of the industrial area and the city of Venice, is the one most highly impacted (particularly in the sites located within or in front of the industrial area, which showed very high sediment toxicity and high levels of DNA damage). The Malamocco basin (south-central lagoon) seems to be the least problematic. The southern basin (Chioggia basin) was shown to be impacted by urban contaminants from the town of Chioggia. The northern basin (Treporti basin) presented both impacted sites (high toxicity and high bioaccumulation factor) and relatively unpolluted sites (absence of toxicity, absence of imposex and low levels of bioaccumulation). This review can serve as a basis on which to select pragmatic, cost-effective biomonitoring techniques for environmental effects in lagoon ecosystems.

  9. [The origin and quality of water for human consumption: the health of the population residing in the Matanza-Riachuelo river basin area in Greater Buenos Aires].

    PubMed

    Monteverde, Malena; Cipponeri, Marcos; Angelaccio, Carlos; Gianuzzi, Leda

    2013-04-01

    The aim of this study is to analyze the origin and quality of water used for consumption in a sample of households in Matanza-Riachuelo river basin area in Greater Buenos Aires, Argentina. The results of drinking water by source indicated that 9% of water samples from the public water system, 45% of bottled water samples and 80% of well water samples were not safe for drinking due to excess content of coliforms, Escherichia coli or nitrates. Individuals living in households where well water is the main source of drinking water have a 55% higher chance of suffering a water-borne disease; in the cases of diarrheas, the probability is 87% higher and in the case of dermatitis, 160% higher. The water for human consumption in this region should be provided by centralized sources that assure control over the quality of the water.

  10. Macroalgae, nutrient cycles, and pollutants in the lagoon of Venice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sfriso, A.; Pavoni, B.; Marcomini, A.

    1992-12-01

    The Lagoon of Venice is a wide, shallow coastal basin that extends for about 50 km along the northwest coast of the Adriatic Sea. The lagoon has been substantially modified through the actions of man over the last century through the artificial control of the hydraulic dynamics of the lagoon including the construction of channels to facilitate navigation. The lagoon is subjected to considerable pollutant loading through the drainage of land under cultivation, municipal sewage, and industrial effluents. In this paper are reported the results of observations designed to document recent changes in macroalgal species composition, seasonal cycles of primarymore » producers and nutrient levels, and the effects of the macroalgal community on concentrations of organic and inorganic pollutants. The dominant macroalgae in the lagoon was Ulva rigida, and the levels of plant nutrients and pollutants were influenced by the seasonal cycles of the macroalgal community. 44 refs., 11 figs., 2 tabs.« less

  11. Surface Water Quality Survey of Northern Indian River Lagoon from Sebastian Inlet to Mosquito Lagoon

    NASA Astrophysics Data System (ADS)

    Weaver, R. J.; Webb, B. M.

    2012-12-01

    Following news of an emerging brown tide algal bloom in the northern Indian River Lagoon (IRL), researchers sought to gain insight into the surface water quality in the IRL, as well as the extent of the algae coverage. A Portable SeaKeeper from YSI, mounted to a personal watercraft-based coastal profiling system, autonomously collected and analyzed the surface water. The system operates by recording sample data every 12 seconds while continuously underway at speeds up to and greater than 50 km/hr. The researchers covered a transect that started at Sebastian Inlet and followed a zig-zag path extending up through the Haulover Canal and into the Mosquito Lagoon. The survey path covered 166.7 km, and collected 2248 samples. Along the way stops were made at water quality stations used by the Saint John's River Water Management District, so that the data collected can be incorporated into ongoing monitoring efforts. The system analyzed the surface water for dissolved oxygen, pH, chlorophyll-a, salinity, temperature, turbidity, refined fuels, and CDOM. In the two days following the lagoon survey, the inlets at Port Canaveral and Sebastian were also surveyed for tidal currents and hydrography. The IRL transect survey data recorded evidence of the southern extent of the algae bloom in both chlorophyll-a and pH levels. Visual evidence of the bloom was striking as the water in the northern IRL turned a milk chocolaty brown color. Chlorophyll-a levels in the two inlets suggested bloom activity at these locations; however this bloom was different. This oceanic bloom was a result of a persistent upwelling event along the East Florida shelf, and the color was a paler green-yellow. The near-synoptic nature of the comprehensive lagoon survey, conducted in just over 7 hours, allows researchers to obtain a better understanding of water quality in coastal lagoons. Elevated levels of salinity, temperature, and refined fuels in the northern IRL indicate a low exchange rate and absence

  12. Metagenomic Survey of a Military-Impacted Lagoon in Puerto Rico

    NASA Astrophysics Data System (ADS)

    Davila-Santiago, L.; DeLeon-Rodriguez, N.; LaSanta-Pagan, K. Y.; Kurt, Z.; Padilla-Crespo, E.; Hatt, J.; Spain, J.; Konstantinidis, K.; Massol-Deya, A.

    2016-02-01

    Military practices have left a legacy of contamination worldwide. In Puerto Rico, the east part of the populated Vieques Island was used for over fifty years as a bombing range by the Navy. A year after the base was closed in 2003, the impacted area was designated as a Superfund site. Previous studies have shown elevated levels of heavy metals, explosives (e.g. RDX, TNT, HMX), and other toxic chemicals at the site. The Anones Lagoon, located in the middle of the bombing range is one of the most polluted spots within the site. Intermittently, the lagoon is connected through a channel to the Caribbean Sea. In order to describe the microbial diversity and its potential contribution to natural attenuation of explosives, sediment samples have been collected since 2005. Sediment from reference lagoons (San Juan and Cabo Rojo) have also been sampled and analyzed in parallel for comparisons. Total DNA was extracted and sequenced using Ilumina My-Seq platform. Results indicate that Gammaproteobacteria were abundant in all lagoons samples but the Vieques lagoon harbors overall different microbial taxa. Alpha diversity analysis showed that Anones was less diverse compared to the pristine Cabo Rojo lagoon. Importantly, a clear shift was seen in the Anones Lagoon in 2013 compared to 2005, were Halomonas spp. became dominant (up to 25%) while other groups like Marinobacter showed signs of enrichment as well. Interestingly, these groups have been shown to degrade explosive-related chemicals in tropical sediments. Functional gene annotation of the Anones metagenome showed the presence of RDX degradation genes such as cytochrome p450. This study is the first comparative metagenomic survey of lagoons in Puerto Rico that explored the microbial diversity and biodegradation potential at Vieques.

  13. Sludge Lagoons. Sludge Treatment and Disposal Course #166. Instructor's Guide [and] Student Workbook.

    ERIC Educational Resources Information Center

    Sharman, Ronald M.

    This lesson describes three different types of sludge lagoons: (1) drying lagoons; (2) facultative lagoons; and (3) anaerobic lagoons. Normal operating sequence and equipment are also described. The lesson is designed to be used in sequence with the complete Sludge Treatment and Disposal Course #166 or as an independent lesson. The instructor's…

  14. Toxic metals in Venics lagoon sediments: Model, observation, an possible removal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Basu, A.; Molinaroli, E.

    1994-11-01

    We have modeled the distribution of nine toxic metals in the surface sediments from 163 stations in the Venice lagoon using published data. Three entrances from the Adriatic Sea control the circulation in the lagoon and divide it into three basins. We assume, for purposes of modeling, that Porto Marghera at the head of the Industrial Zone area is the single source of toxic metals in the Venice lagoon. In a standing body of lagoon water, concentration of pollutants at distance x from the source (C{sub 0}) may be given by C=C{sub 0}e{sup -kx} where k is the rate constantmore » of dispersal. We calculated k empirically using concentrations at the source, and those farthest from it, that is the end points of the lagoon. Average k values (ppm/km) in the lagoon are: Zn 0.165, Cd 0.116, Hg 0.110, Cu 0.105, Co 0.072, Pb 0.058, Ni 0.008, Cr (0.011) and Fe (0.018 percent/km), and they have complex distributions. Given the k values, concentration at source (C{sub 0}), and the distance x of any point in the lagoon from the source, we have calculated the model concentrations of the nine metals at each sampling station. Tides, currents, floor morphology, additional sources, and continued dumping perturb model distributions causing anomalies (observed minus model concentrations). Positive anomalies are found near the source, where continued dumping perturbs initial boundary conditions, and in areas of sluggish circulation. Negative anomalies are found in areas with strong currents that may flush sediments out of the lagoon. We have thus identified areas in the lagoon where higher rate of sediment removal and exchange may lesson pollution. 41 refs., 4 figs., 3 tabs.« less

  15. Organic micropollutants in wet and dry depositions in the Venice Lagoon.

    PubMed

    Gambaro, Andrea; Radaelli, Marta; Piazza, Rossano; Stortini, Angela Maria; Contini, Daniele; Belosi, Franco; Zangrando, Roberta; Cescon, Paolo

    2009-08-01

    Atmospheric transport is an important route by which pollutants are conveyed from the continents to both coastal and open sea. The role of aerosol deposition in the transport of polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs) and polybromodiphenyls ethers (PBDEs) to water and soil systems has been evaluated by measuring their concentrations in wet and dry depositions to the Venice Lagoon. The organic micropollutant flux data indicate that they contribute to the total deposition flux in different ways through wet and dry deposition, showing that the prevalent contribution derives from wet deposition. The fluxes calculated for PBDEs, showed the prevalence of 47, 99, 100 and 183 congeners, both in dry and wet fluxes. With regard to PCBs, the flux of summation operatorPCB for wet deposition is in the same order of magnitude of the diffusive flux at the air-water interface. The PAH fluxes obtained in the present study are similar to those obtained in previous studies on the atmospheric bulk deposition to the Venice Lagoon. The ratios between Phe/Ant and Fl/Py indicate that the pollutants sources are pyrolytic, deriving from combustion fuels.

  16. Biomarker responses and contamination levels in the clam Ruditapes philippinarum for biomonitoring the Lagoon of Venice (Italy).

    PubMed

    Matozzo, Valerio; Binelli, Andrea; Parolini, Marco; Locatello, Lisa; Marin, Maria Gabriella

    2010-03-01

    A multibiomarker approach was used to assess effects of environmental contaminants in the clam Ruditapes philippinarum from the Lagoon of Venice. Bivalves were collected in 8 sites of the Lagoon (Campalto, Marghera, Palude del Monte, Valle di Brenta, Cà Roman, San Servolo, Fusina and Canale Dese), differently influenced by both anthropogenic impact and natural conditions. The following biomarkers were chosen: total haemocyte count and lysozyme activity in cell-free haemolymph as immunomarkers, acetylcholinesterase activity in gills as a biomarker of exposure to neurotoxic compounds, vitellogenin-like protein levels in both digestive gland and cell-free haemolymph as a biomarker of exposure to estrogenic compounds, and survival-in-air widely used to evaluate general stress conditions in clams. In addition, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), 1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDT) and its breakdown products (DDE, DDD), hexachlorobenzene (HCB) and hexachlorocyclohexane (HCH) were measured in clams. Results demonstrated that the integrated approach between biomarkers and chemical analyses in R. philippinarum is a useful tool in biomonitoring the Lagoon of Venice. The biomarker responses suggested quite similar contamination levels in the entire Lagoon, although the relative impact of differing classes of pollutants changed among sites according to potential sources, as chemical analyses demonstrated. Overall, among the sampling sites investigated, Palude del Monte can represent an environmental risk area, bearing in mind its peculiar use for clam culture.

  17. First steps of ecological restoration in Mediterranean lagoons: Shifts in phytoplankton communities

    NASA Astrophysics Data System (ADS)

    Leruste, A.; Malet, N.; Munaron, D.; Derolez, V.; Hatey, E.; Collos, Y.; De Wit, R.; Bec, B.

    2016-10-01

    Along the French Mediterranean coast, a complex of eight lagoons underwent intensive eutrophication over four decades, mainly related to nutrient over-enrichment from continuous sewage discharges. The lagoon complex displayed a wide trophic gradient from mesotrophy to hypertrophy and primary production was dominated by phytoplankton communities. In 2005, the implementation of an 11 km offshore outfall system diverted the treated sewage effluents leading to a drastic reduction of anthropogenic inputs of nitrogen and phosphorus into the lagoons. Time series data have been examined from 2000 to 2013 for physical, chemical and biological (phytoplankton) variables of the water column during the summer period. Since 2006, total nitrogen and phosphorus concentrations as well as chlorophyll biomass strongly decreased revealing an improvement in lagoon water quality. In summertime, the decline in phytoplankton biomass was accompanied by shifts in community structure and composition that could be explained by adopting a functional approach by considering the common functional traits of the main algal groups. These phytoplankton communities were dominated by functional groups of small-sized and fast-growing algae (diatoms, cryptophytes and green algae). The trajectories of summer phytoplankton communities displayed a complex response to changing nutrient loads over time. While diatoms were the major group in 2006 in all the lagoons, the summer phytoplankton composition in hypertrophic lagoons has shifted towards green algae, which are particularly well adapted to summertime conditions. All lagoons showed increasing proportion and occurrence of peridinin-rich dinophytes over time, probably related to their capacity for mixotrophy. The diversity patterns were marked by a strong variability in eutrophic and hypertrophic lagoons whereas phytoplankton community structure reached the highest diversity and stability in mesotrophic lagoons. We observe that during the re

  18. [Transparency in public sector acquisitions. The case of hospitals in the City of Buenos Aires].

    PubMed

    Rossi, T; Murillo Fort, C; Puente Karolys, J C

    2002-01-01

    This paper deals with corruption and the lack of transparency in public sector purchases as well as with the main instruments to obtain adequate results in purchase negotiation.Firstly, we discuss how corruption causes concern to national governments, international organizations, academic centers, non-governmental organizations and society in general. The consequences of corruption in Argentina and other Latin American countries are highlighted, especially the effect of corruption on economic growth and the way it creates economic inefficiency and inequality.Secondly, the database created by the Subsecretary of Strategic Management of the Autonomous Government of the City of Buenos Aires is analyzed. The central purpose of this study is to evaluate the impact of the Administrative Reform of 1998 on the prices of 24 products acquired by 13 general acute care hospitals from 1998-1999. The weighted prices, the number of units purchased and the total number of contracts given in this period, as well as the products with the greatest utilization rate, are analyzed. Multivariante analysis was used to identify hospitals with appropriate activity and efficient budget administration (activity and negotiation indicators). Price development was analyzed using the regression technique (ordinary least squares), which demonstrated an 8% reduction in prices for the year 1999. The contribution of each hospital to this variation is presented using dummy variables. Thus, six of the 13 hospitals significantly contributed to the decrease in prices. Of these six, three hospitals also contributed to reduction in price dispersion. The results obtained allow us to conclude that, if public hospitals have adequate purchase negotiation instruments and a uniform legal framework, they can achieve a good level of activity. Furthermore, public hospitals can contribute to reductions in price and price dispersion, at the same time as improving efficiency in the assignation and utilization of

  19. Cosmogenic Surface-Exposure Dating of Boulders on Last-Glacial and Late-Glacial Moraines, Lago Buenos Aires, Argentina: Interpretive Strategies and Paleoclimate Implications

    NASA Astrophysics Data System (ADS)

    Douglass, D. C.; Singer, B. S.; Kaplan, M. R.; Mickelson, D. M.; Caffee, M.

    2005-12-01

    The most substantial and least quantifiable source of uncertainty in cosmogenic surface-exposure datasets is the variable exposure histories of boulders from the same landform. The development of precise and accurate chronologies requires distinguishing boulders that best reflect the age of the landform from those which are outliers. We use the Mean Square of Weighted Deviates statistic and cumulative frequency plots to identify groups of samples that have statistically similar ages based on the number of samples and the uncertainty associated with the analyses. This group of samples most likely represents the best estimate of the landform age. We use these tools to interpret 49 surface-exposure ages from six last-glacial and late-glacial moraines at Lago Buenos Aires, Argentina (LBA; 71.0W, 46.5S). Seven of the orty-nine samples are identified as anomalously young, and are interpreted to have been exhumed after moraine deposition. The remaining samples indicate that glacial advances or still-stands of the ice margin occurred at 22.7±0.9, 21.4±1.9, 19.8±1.1, 17.0±0.8, 15.7±0.6, and 14.4±0.9 ka (±2 σ). This maximum ice extent is roughly synchronous with maximum global ice volume and several of the re-advances are contemporaneous with Heinrich events and other Northern Hemisphere cold periods. The late-glacial readvance at ca. 14.4 ka is contemporaneous with the Antarctic Cold Reversal (ACR), and precedes the Younger Dryas Chronozone (YD). No evidence for a Younger Dryas glacial advance has been found in the Lago Buenos Aires basin. This precise glacial chronology indicates there were significant and important differences in climate across southern South America. The timing of maximum ice extent and onset of deglaciation at LBA occur ~4000 years later than in the Chilean Lake District (41S). Fossil pollen from the CLD area indicates cooler conditions between ca. 14.2 and 11.2, and increased silt in a nearby lake core provides indirect evidence for glacial

  20. DESIGN INFORMATION REPORT: PROTECTION OF WASTEWATER LAGOON INTERIOR SLOPES

    EPA Science Inventory

    A problem common to many wastewater treatment and storage lagoons is erosion of the interior slopes. Erosion may be caused by surface runoff and wind-induced wave action. The soils that compose the steep interior slopes of lagoons are especially susceptible to erosion and slumpin...

  1. Coastal Processes with Improved Tidal Opening in Chilika Lagoon (east Coast of India)

    NASA Astrophysics Data System (ADS)

    Jayaraman, Girija; Dube, Anumeha

    Chilika Lagoon (19°28-19°54¢N and 85°06-85°36¢E) is the largest brackish water lagoon with estuarine character. Interest in detailed analysis of the ecology of the lagoon and the various factors affecting it is due to the opening of the new mouth on September 23, 2000 to resolve the threat to its environment from various factors - Eutrophication, weed proliferation, siltation, industrial pollution, and depletion of bioresources. The opening of the new mouth has changed the lagoon environment significantly with better socio­economic implications. There is a serious concern if the significant improvement in the biological productivity of the lagoon post-mouth opening is indeed sustainable. The present study focuses on the changes in the coastal processes as a result of the additional opening of a new mouth. Our results based on mathematical modeling and numerical simulation compare the dynamics, nutrient, and plankton distribution before and after the new mouth opening. The model could confirm the significant increase (14-66% depending on the sector) in the salinity after the new mouth opening, the maximum change being observed in the channel which connects the lagoon to the sea. The constriction in the lagoon which blocks the tidal effects entering the lagoon must be responsible for maintaining the main body of the lagoon with low salinity. The ecological model is first tested for different sectors individually before a complete model, including the entire lagoon area, is included incorporating their distinct characteristics. The model is validated with available observations of plankton and nutrients made before the opening of the new mouth. It predicts the annual distribution of plankton in all the sectors of the lagoon for post-mouth opening which is to be verified when the data will be forthcoming.

  2. Coastal Processes with Improved Tidal Opening in Chilika Lagoon (east Coast of India)

    NASA Astrophysics Data System (ADS)

    Jayaraman, Girija; Dube, Anumeha

    Chilika Lagoon (19°28-19°54'N and 85°06-85°36'E) is the largest brackish water lagoon with estuarine character. Interest in detailed analysis of the ecology of the lagoon and the various factors affecting it is due to the opening of the new mouth on September 23, 2000 to resolve the threat to its environment from various factors — Eutrophication, weed proliferation, siltation, industrial pollution, and depletion of bioresources. The opening of the new mouth has changed the lagoon environment significantly with better socio-economic implications. There is a serious concern if the significant improvement in the biological productivity of the lagoon post-mouth opening is indeed sustainable. The present study focuses on the changes in the coastal processes as a result of the additional opening of a new mouth. Our results based on mathematical modeling and numerical simulation compare the dynamics, nutrient, and plankton distribution before and after the new mouth opening. The model could confirm the significant increase (14-66% depending on the sector) in the salinity after the new mouth opening, the maximum change being observed in the channel which connects the lagoon to the sea. The constriction in the lagoon which blocks the tidal effects entering the lagoon must be responsible for maintaining the main body of the lagoon with low salinity. The ecological model is first tested for different sectors individually before a complete model, including the entire lagoon area, is included incorporating their distinct characteristics. The model is validated with available observations of plankton and nutrients made before the opening of the new mouth. It predicts the annual distribution of plankton in all the sectors of the lagoon for post-mouth opening which is to be verified when the data will be forthcoming.

  3. Chemistry of modern sediments in a hypersaline lagoon, north of Jeddah, Red Sea

    NASA Astrophysics Data System (ADS)

    El-Sayed, Mahmoud Kh.

    1987-10-01

    Previous studies of modern peritidal sedimentary environments of the Red Sea, such as hypersaline lagoons and sea-marginal flats, have concentrated on its northern part, particularly in the Gulf of Aqaba. However, little is known about lagoon sediments in other localities along the Red Sea coastal stretches. This paper deals with the chemical characteristics of the sediments of a hypersaline (Ras Hatiba) lagoon, north of Jeddah, Saudi Arabia. The chemistry of hypersaline lagoon sediments is considerably changed following the modifications to the water chemistry by evaporation and precipitation. Ras Hatiba lagoon is a hypersaline elongated water body connected to the Red Sea by a narrow and shallow opening. The total area of the lagoon is c. 30 km 2. Coarse bioclastic sands are dominant in the lagoon and mostly surround lithified calcareous grounds. However, fine silt and clay sediments are present in separate patches. The sediments are rich in carbonates (average 78·5%) and organic carbon (average 7·3%), although they are negatively correlated. Calcium (average 25·1%) and magnesium (average 10·8‰) show a similar distribution pattern in the lagoon sediments. Strontium (average 5·2‰) is positively correlated with calcium. Sodium and potassium are relatively highly concentrated in the sediments (average 118 ppm and 173 ppm, respectively). Magnesium and strontium are of prime importance in the process of mineralization and diagenesis. The sabkha formation surrounding the lagoon is of low carbonate and organic carbon content, compared with the lagoon sediments, whilst it is characterized by high magnesium, sodium and potassium concentrations. Ras Hatiba lagoon sediments and sabkha resemble those of the northern Red Sea in the Gulfs of Aqaba and Suez and the Arabian Gulf in their major sedimentological and chemical characteristics.

  4. The distribution of salinity and main forcing effects in the Berre lagoon

    NASA Astrophysics Data System (ADS)

    Roux, Bernard; Alekseenko, Elena; Chen, Paul Gang; Kharif, Christian; Kotarba, Richard; Fougere, Dominique

    2014-05-01

    The results from previous studies in lagoons and well mixed estuaries indicate that salt transport is primarily in response to advection associated with freshwater outflow, tidal diffusion, and to shear effects arising from spatial correlations of vertical and especially transverse deviations in salinity and current speed (Smith, 1994). Therefore, the inflow of fresh and salt water into coastal lagoons is an important factor influencing the structure and function of lagoonal ecosystems worldwide (Lirman et al., 2007). The predominance of marine or freshwater inflow leads to the different ecosystems. Among several lagoons located along the Mediterranean shore of France, the Berre lagoon has been under intense anthropogenic pressure for several decades (Delpy et al., 2012). Moreover, the salinity level of the Berre lagoon was varying dramatically from the 19th century up to now. In this work, a special attention is focused on the salinity variation in the Berre lagoon due to the three dominant abiotic forcing mechanisms, i.e., incoming sea tide, runoff from a hydropower and a strong wind. Four different model scenarios were considered in order to examine the impact of each forcing mechanism or combined effects, i.e. : (a) tide only, (b) runoff only, (c) combined tide and runoff, and (d) an N-NW wind, tide and runoff together. Numerical modeling and interpretation of numerical results are based on three-dimensional hydrodynamic model MARS3D. It is found that the strongest negative impact is related to the huge hydropower runoffs, inducing the desalinization of the surface and subsurface waters not only in the centre of the lagoon, but also in the entire water column in the coastal seagrass recolonization zones. In the absence of wind, the huge inputs of freshwater from the hydropower lead to a haline stratification and thus, to anoxic conditions, making most of the lagoon unproductive. On the contrary, strong winds play a positive role on the salinity level of the

  5. Environmental Assessment of the Bolinas Lagoon: a study utilizing benthic foraminifera

    NASA Astrophysics Data System (ADS)

    Benton, L.; Espinoza Madrid, N.; Grande, C.

    2016-12-01

    Benthic foraminifera have long been recognized for their utility in environmental assessments. They are abundant, diverse, and found in all marine environments, but species distributions depend largely on local environmental conditions. This study analyses benthic foraminiferal assemblages from the Bolinas Lagoon, Marin County, California. The Careers in Science Intern Program collected 36 sediment samples from 13 sites within the Bolinas Lagoon. Foraminiferal assemblages for each site are reported, and species richness, relative abundance, and Shannon's diversity calculated. Results indicate that Shannon's diversity is low throughout the Bolinas Lagoon and stress tolerant taxa are abundant, which suggests that current conditions in the Bolinas Lagoon are sub optimal.

  6. Estimates of the radiological dose to people living on Bikini Island for two weeks while diving in and around the sunken ships in Bikini Lagoon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robison, W.L.

    1990-09-01

    Bikini Island and Bikini Lagoon were contaminated by fallout from nuclear weapons tests conducted at the atoll by the United States from 1946 to 1958. The second test, Baker, of the Crossroads series was an underwater detonation in 1946 that sank several ships in the lagoon, including the USS Saratoga and the Japanese battleship Nagato. The ships received high-intensity gamma-ray and neutron bombardment from the Baker test, which induced radioactivity in the metal structures. Some of the tests conducted after the Baker shot (there were 21 tests in all) injected contaminated carbonate particles into the air, some of which weremore » deposited across the lagoon surface. Most of this contaminated soil then settled onto the ships` decks and other structures and on the lagoon bottom. These sunken ships provide an interesting location for divers. Recreational diving and swimming in and around the ships raises the question of the potential radiological dose from the radionuclides present in or on the ships and in the lagoon sediments. The purpose of this paper, therefore, is to present an analysis of the potential radiological dose to persons who would dive near the sunken ships and live on Bikini Island for a short period of time.« less

  7. Estimates of the radiological dose to people living on Bikini Island for two weeks while diving in and around the sunken ships in Bikini Lagoon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robison, W.L.

    1990-09-01

    Bikini Island and Bikini Lagoon were contaminated by fallout from nuclear weapons tests conducted at the atoll by the United States from 1946 to 1958. The second test, Baker, of the Crossroads series was an underwater detonation in 1946 that sank several ships in the lagoon, including the USS Saratoga and the Japanese battleship Nagato. The ships received high-intensity gamma-ray and neutron bombardment from the Baker test, which induced radioactivity in the metal structures. Some of the tests conducted after the Baker shot (there were 21 tests in all) injected contaminated carbonate particles into the air, some of which weremore » deposited across the lagoon surface. Most of this contaminated soil then settled onto the ships' decks and other structures and on the lagoon bottom. These sunken ships provide an interesting location for divers. Recreational diving and swimming in and around the ships raises the question of the potential radiological dose from the radionuclides present in or on the ships and in the lagoon sediments. The purpose of this paper, therefore, is to present an analysis of the potential radiological dose to persons who would dive near the sunken ships and live on Bikini Island for a short period of time.« less

  8. Shiga toxin-producing Escherichia coli O157 in beef and chicken burgers, and chicken carcasses in Buenos Aires, Argentina.

    PubMed

    Chinen, Isabel; Epszteyn, Sergio; Melamed, Celia L; Aguerre, Lorena; Martínez Espinosa, Estela; Motter, Mariana M; Baschkier, Ariela; Manfredi, Eduardo; Miliwebsky, Elizabeth; Rivas, Marta

    2009-06-30

    We describe the isolation and characterization of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157:H7 from cooked and uncooked beef and chicken burgers and from chicken carcasses collected during sampling procedures in 2001 and 2002 in Buenos Aires City, Argentina. Of the 24 STEC O157:H7 strains isolated, 20 were recovered from 19 (6.8%) out of 279 samples of beef and chicken burgers, and 4 strains from 4 (10.3%) out of 39 chicken carcasses. The samples were analyzed following the USDA/FSIS 2002 method. The prevalent stx genotype was stx(2) and stx(2c) (12 strains, 50%). All strains were characterized as eae and ehxA-positive. By XbaI-PFGE, the strains yielded 10 different patterns. Eighteen out of 24 strains were grouped in four clusters: #1 (4 strains, AREXHX01.0043), #2 (4 strains, AREXHX01.0022), #3 (8 strains, AREXHX01.0139), and #4 (2 strains, AREXHX01.0200). Identical strains by phage typing, stx genotyping and PFGE were detected in uncooked and cooked beef and chicken burgers in different restaurants, which had been collected on the same or different sampling dates. These findings help to underline the importance of STEC O157 detection in meat products, to improve active surveillance, and to define control strategies in order to prevent new cases of STEC infection.

  9. Modeling the effect of heat fluxes on ammonia and nitrous oxide emissions from an anaerobic swine waste treatment lagoon using artificial neural network

    USDA-ARS?s Scientific Manuscript database

    Understanding factors that affect ammonia and nitrous emissions from anaerobic swine waste treatment lagoons or any animal waste receptacles is a necessary first step in deploying potential remediation options. In this study, we examined the various meteorological factors (i.e., air temperatures, s...

  10. Evaluation of short-rotation woody crops to stabilize a decommissioned swine lagoon

    Treesearch

    K.C. Dipesh; Rodney E. Will; Thomas C. Hennessey; Chad J. Penn

    2012-01-01

    Fast growing tree stands represent an environmentally friendly, less expensive method for stabilization of decommissioned animal production lagoons than traditional lagoon closure. We tested the feasibility of using short-rotation woody crops (SRWCs) in central Oklahoma to close a decommissioned swine lagoon by evaluating the growth performance and nutrient uptake of...

  11. [Safe and family-centered maternity hospitals: organizational culture of maternity hospitals in the province of Buenos Aires].

    PubMed

    Ramos, Silvina; Romero, Mariana; Ortiz, Zulma; Brizuela, Vanessa

    2015-12-01

    In 2010, the Safe and Family-Centered Maternity Hospitals initiative was launched in order to transform large public maternity centers into settings where safe practices are implemented and the rights of women, newborn infants and families are warranted. As a result, the paradigm of perinatal care was modified. This article reports on the findings of organizational culture as a component for the implementation of the initiative. The sample was selected in a non-probabilistic way and was made up of 29 public hospitals located in the province of Buenos Aires that participated in the initiative. During 2011 and 2012, an anonymous, self-administered survey was completed by members of the Department of Neonatology and the Department of Obstetrics. The survey collected information on three dimensions of the organizational culture: organizational environment, safe practices, and facilitation of change. A total of 1828 surveys were collected; 51% of survey respondents stated that there is a need to improve communication by having more meetings, while 60% made a positive assessment of various aspects of leadership. Work overload was described as the main cause of conflicts by 60%. Approximately 25% agreed and showed commitment with the initiative of transforming maternity centers. Adherence to practices was dissimilar depending on the practice, but half of survey respondents reported that there were genuine reasons for change. The assessment of the organizational culture showed that commitment to the Safe and Family-Centered Maternity Hospitals initiative is yet to be consolidated, and the evaluation of leadership is not comprehensive. Work overload and communication failures are the main reasons for conflict.

  12. Seasonal Variability in Mercury Speciation within Select Coastal Lagoons of Central California

    NASA Astrophysics Data System (ADS)

    Ganguli, P. M.; Conaway, C. H.; Dimova, N. T.; Swarzenski, P. W.; Kehrlein, N. C.; Flegal, A. R.

    2011-12-01

    Coastal lagoons may play an important role in mercury biogeochemical cycling at the land-sea margin. Along the coast of California, these systems are seasonally dynamic, behaving as estuaries during the wet season and as lagoons in the dry season when ephemeral sand berms develop and isolate terrestrial freshwater from direct exchange with the ocean. As a consequence, many lagoons become eutrophic in the dry season and are characterized by high nutrient and low dissolved oxygen concentrations. Because monomethylmercury (MMHg) production can be mediated by anaerobic bacteria, coastal lagoons are a potential source of biologically available MMHg that may be transported to the nearshore environment via submarine groundwater discharge. To evaluate the importance of coastal lagoons at the land-sea margin, we quantified total mercury (HgT) and MMHg concentrations in surface water and coastal seawater from six sites during dry and wet season conditions, including one storm event. Additionally, we conducted a tidal study at one lagoon in which we sampled surface water, seawater, and groundwater over a 10-hour period during a falling tide (+1.63 to 0.00 m). Groundwater was collected using a multi-port piezometer screened at depths ranging from 1 m to a few centimeters below the lagoon's sediment-water interface. This enabled us to characterize surface water - groundwater interaction. During wet season conditions, the average unfiltered HgT (U-HgT) concentration in surface water at the tidal study lagoon was 13 pM and did not fluctuate in response to tidal changes. Filtered (< 0.45 μm) HgT (F-HgT) concentrations in the lagoon were similar to U-HgT concentrations during high tide and decreased to 8 pM during low tide. Groundwater F-HgT concentrations were about 1.5 pM at a depth of 1 m and systematically increased at shallower depths, reaching approximately 6 pM near the surface. These data indicate F-HgT exchange between the lagoon and groundwater to a depth of at least 1 m

  13. The effect of floods on sediment contamination in a microtidal coastal lagoon: the lagoon of Lesina, Italy.

    PubMed

    D'Adamo, Raffaele; Specchiulli, Antonietta; Cassin, Daniele; Botter, Margherita; Zonta, Roberto; Fabbrocini, Adele

    2014-10-01

    The effects on the microtidal lagoon of Lesina of runoff and the discharge of water and material from agricultural activities were investigated combining chemical analyses of pollutants [11 metals and 16 priority polycyclic aromatic compounds (PAHs)], determination of organic matter and grain size, and performance of innovative ecotoxicological tests. For metals, enrichment factors >3 for arsenic, nickel, and copper (Cu) were observed in the eastern zone of the lagoon, which is affected by nearby urban activities with discharge of water and domestic waste and by agricultural input with waters rich in fertilizers. Cu was correlated with no other metal, and its high concentrations (≤77 µg g(-1)) may result from the use of Cu-based fungicides in vineyards. Total PAHs (2,230 ± 3,150 ng g(-1)) displayed a wide range of concentrations with hot spots near freshwater inputs from the part of the catchment area exploited for wheat crops. Pyrolitic contamination also emerged, with higher-mass PAH congeners, such as asphalt, bitumen or coal, usually present in higher fractions as the dominant components. Ecotoxicological evaluations recorded moderate to high toxicity levels; the innovative MOT test bioassay showed good discriminatory ability because it identified a lagoon area whose inputs mainly depend on agricultural activities and which is impacted by metals rather than PAHs. Floods during periods of heavy rain and the discharge of water and material from agricultural activities may impact vulnerable systems, such as the lagoon of Lesina, where the presence of hot spots with remarkably high pollution values was observed.

  14. β-lactamases produced by amoxicillin-clavulanate-resistant enterobacteria isolated in Buenos Aires, Argentina: a new blaTEM gene.

    PubMed

    Di Conza, José A; Badaracco, Alejandra; Ayala, Juan; Rodríguez, Cynthia; Famiglietti, Angela; Gutkind, Gabriel O

    2014-01-01

    Resistance to β-lactam/β-lactamase inhibitors in enterobacteria is a growing problem that has not been intensively studied in Argentina. In the present work, 54/843 enterobacteria collected in a teaching hospital of Buenos Aires city were ampicillin-sulbactam-resistant isolates remaining susceptible to second- and third-generation cephalosporins. The enzymatic mechanisms present in the isolates, which were also amoxicillin-clavulanic acid (AMC)-resistant (18/54) were herein analyzed. Sequencing revealed two different variants of blaTEM-1, being blaTEM-1b the most frequently detected allelle (10 Escherichia coli, 3 Klebsiella pneumoniae, 2 Proteus mirabilis and 1 Raoultella terrigena) followed by blaTEM-1a (1 K. pneumoniae). Amoxicillin-clavulanate resistance seems to be mainly associated with TEM-1 overproduction (mostly in E. coli) or co-expressed with OXA-2-like and/or SHV β-lactamases (K. pneumoniae and P. mirabilis). A new blaTEM variant (TEM-163) was described in an E. coli strain having an AMC MIC value of 16/8μg/ml. TEM-163 contains Arg275Gln and His289Leu amino acid substitutions. On the basis of the high specific activity and low IC50 for clavulanic acid observed, the resistance pattern seems to be due to overproduction of the new variant of broad spectrum β-lactamase rather than to an inhibitor-resistant TEM (IRT)-like behavior. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  15. Biostratigraphy and biochronology of the Monte Hermoso Formation (early Pliocene) at its type locality, Buenos Aires Province, Argentina

    NASA Astrophysics Data System (ADS)

    Tomassini, Rodrigo L.; Montalvo, Claudia I.; Deschamps, Cecilia M.; Manera, Teresa

    2013-12-01

    The Monte Hermoso Formation, cropping out at its type locality of Farola Monte Hermoso (Buenos Aires Province), is a classical fossiliferous unit of the South American Neogene, highlighted by the abundance and diversity of its vertebrate remains. However, its biostratigraphy and age have been largely debated, and numerous discrepancies and controversies have been stated. In this regard, the result of the analysis of new materials recovered from the different levels of this formation, following a strict control of stratigraphic provenance, is here reported. As well, the provenance of specimens of previous collections has been evaluated. The studied assemblage consists of Osteichthyes, Amphibia, Reptilia, Aves and Mammalia. These latter are the most numerous and belong to the Didelphimorphia, Polydolopimorphia, Rodentia, Notoungulata, Litopterna and Xenarthra. The recorded taxa suggest no important faunistic variations among the different levels of the Monte Hermoso Formation that would imply significant chronological differences, and hence, justify the recognition of two biostratigraphic units. The analysis of the first and last records as well as the taxa considered as exclusive, does not support the validity of the biozones of Trigodon gaudryi and Neocavia depressidens previously proposed. On this basis, a new scheme for the Monte Hermoso Formation at its type locality is proposed, including a new single biostratigraphic unit. This unit is the Eumysops laeviplicatus Range Zone, which represents the biostratigraphic base for the Montehermosan Stage/Age of the early Pliocene.

  16. Sludge-Drying Lagoons: a Potential Significant Methane Source in Wastewater Treatment Plants.

    PubMed

    Pan, Yuting; Ye, Liu; van den Akker, Ben; Ganigué Pagès, Ramon; Musenze, Ronald S; Yuan, Zhiguo

    2016-02-02

    "Sludge-drying lagoons" are a preferred sludge treatment and drying method in tropical and subtropical areas due to the low construction and operational costs. However, this method may be a potential significant source of methane (CH4) because some of the organic matter would be microbially metabolized under anaerobic conditions in the lagoon. The quantification of CH4 emissions from lagoons is difficult due to the expected temporal and spatial variations over a lagoon maturing cycle of several years. Sporadic ebullition of CH4, which cannot be easily quantified by conventional methods such as floating hoods, is also expected. In this study, a novel method based on mass balances was developed to estimate the CH4 emissions and was applied to a full-scale sludge-drying lagoon over a three year operational cycle. The results revealed that processes in a sludge-drying lagoon would emit 6.5 kg CO2-e per megaliter of treated sewage. This would represent a quarter to two-thirds of the overall greenhouse gas (GHG) emissions from wastewater-treatment plants (WWTPs). This work highlights the fact that sludge-drying lagoons are a significant source of CH4 that adds substantially to the overall GHG footprint of WWTPs despite being recognized as a cheap and energy-efficient means of drying sludge.

  17. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation.

    PubMed

    McMurtry, G M; Schneider, R C; Colin, P L; Buddemeier, R W; Suchanek, T H

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. Studies of the burial of fallout radionuclides have been conducted on the islands and in several of the large craters, but studies of their vertical distribution have been limited to about the upper 20 cm of the lagoon sediments. We have found elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  18. Spatiotemporal variation of bacterial community composition and possible controlling factors in tropical shallow lagoons.

    PubMed

    Laque, Thaís; Farjalla, Vinicius F; Rosado, Alexandre S; Esteves, Francisco A

    2010-05-01

    Bacterial community composition (BCC) has been extensively related to specific environmental conditions. Tropical coastal lagoons present great temporal and spatial variation in their limnological conditions, which, in turn, should influence the BCC. Here, we sought for the limnological factors that influence, in space and time, the BCC in tropical coastal lagoons (Rio de Janeiro State, Brazil). The Visgueiro lagoon was sampled monthly for 1 year and eight lagoons were sampled once for temporal and spatial analysis, respectively. BCC was evaluated by bacteria-specific PCR-DGGE methods. Great variations were observed in limnological conditions and BCC on both temporal and spatial scales. Changes in the BCC of Visgueiro lagoon throughout the year were best related to salinity and concentrations of NO (3) (-) , dissolved phosphorus and chlorophyll-a, while changes in BCC between lagoons were best related to salinity and dissolved phosphorus concentration. Salinity has a direct impact on the integrity of the bacterial cell, and it was previously observed that phosphorus is the main limiting nutrient to bacterial growth in these lagoons. Therefore, we conclude that great variations in limnological conditions of coastal lagoons throughout time and space resulted in different BCCs and salinity and nutrient concentration, particularly dissolved phosphorus, are the main limnological factors influencing BCC in these tropical coastal lagoons.

  19. An integrated Pan-European perspective on coastal Lagoons management through a mosaic-DPSIR approach

    PubMed Central

    Dolbeth, Marina; Stålnacke, Per; Alves, Fátima L.; Sousa, Lisa P.; Gooch, Geoffrey D.; Khokhlov, Valeriy; Tuchkovenko, Yurii; Lloret, Javier; Bielecka, Małgorzata; Różyński, Grzegorz; Soares, João A.; Baggett, Susan; Margonski, Piotr; Chubarenko, Boris V.; Lillebø, Ana I.

    2016-01-01

    A decision support framework for the management of lagoon ecosystems was tested using four European Lagoons: Ria de Aveiro (Portugal), Mar Menor (Spain), Tyligulskyi Liman (Ukraine) and Vistula Lagoon (Poland/Russia). Our aim was to formulate integrated management recommendations for European lagoons. To achieve this we followed a DPSIR (Drivers-Pressures-State Change-Impacts-Responses) approach, with focus on integrating aspects of human wellbeing, welfare and ecosystem sustainability. The most important drivers in each lagoon were identified, based on information gathered from the lagoons’ stakeholders, complemented by scientific knowledge on each lagoon as seen from a land-sea perspective. The DPSIR cycles for each driver were combined into a mosaic-DPSIR conceptual model to examine the interdependency between the multiple and interacting uses of the lagoon. This framework emphasizes the common links, but also the specificities of responses to drivers and the ecosystem services provided. The information collected was used to formulate recommendations for the sustainable management of lagoons within a Pan-European context. Several common management recommendations were proposed, but specificities were also identified. The study synthesizes the present conditions for the management of lagoons, thus analysing and examining the activities that might be developed in different scenarios, scenarios which facilitate ecosystem protection without compromising future generations. PMID:26776151

  20. Mechanism of nitrogen removal in wastewater lagoon: a case study.

    PubMed

    Vendramelli, Richard A; Vijay, Saloni; Yuan, Qiuyan

    2017-06-01

    Ammonia being a nutrient facilitates the growth of algae in wastewater and causes eutrophication. Nitrate poses health risk if it is present in drinking water. Hence, nitrogen removal from wastewater is required. Lagoon wastewater treatment systems have become common in Canada these days. The study was conducted to understand the nitrogen removal mechanisms from the existing wastewater treatment lagoon system in the town of Lorette, Manitoba. The lagoon system consists of two primary aerated cells and two secondary unaerated cells. Surface samples were collected periodically from lagoon cells and analysed from 5 May 2015 to 9 November 2015. The windward and leeward sides of the ponds were sampled and the results were averaged. It was found that the free ammonia volatilization to the atmosphere is responsible for most of the ammonia removal. Ammonia and nitrate assimilation into biomass and biological growth in the cells appears to be the other mechanisms of nitrogen removal over the monitoring period. Factors affecting the nitrogen removal efficiency were found to be pH, temperature and hydraulic residence time. Also, the ammonia concentration in the effluent from the wastewater treatment lagoon was compared with the regulatory standard.

  1. Environmental quality of transitional waters: the lagoon of Venice case study.

    PubMed

    Micheletti, C; Gottardo, S; Critto, A; Chiarato, S; Marcomini, A

    2011-01-01

    The health status of European aquatic environments, including transitional waters such as coastal lagoons, is regulated by the Water Framework Directive (WFD), which requires the classification of the water bodies' environmental quality and the achievement of a good ecological status by 2015. In the Venice lagoon, a transitional water body located in the northeastern part of Italy, the achievement of a good ecological status is hampered by several anthropogenic and natural pressures, such as sediment and water chemical contamination, and sediment erosion. In order to evaluate the lagoon's environmental quality according to the WFD (i.e. 5 quality classes, from High to Bad), an integrated Weight-of-Evidence methodology was developed and applied to classify the quality of the lagoon water bodies, integrating biological, physico-chemical, chemical, ecotoxicological, and hydromorphological data (i.e. Lines of Evidence, LOE). The quality assessment was carried out in two lagoon habitat typologies (previously defined on the basis of morphological, sediment, and hydrodynamic characteristics) which were selected taking into account the ecological gradient from sea to land, and the differences in anthropogenic pressure and contamination levels. The LOE classification was carried out by using indicators scored by comparing site specific conditions to reference conditions measured in lagoon reference sites, or provided by local, national or European regulations (e.g. Environmental Quality Standards, EQS, for chemicals). Finally, the overall quality status for each water body was calculated by a probabilistic approach, i.e. by reporting the final result as the frequency distribution of quality classes. The developed procedure was applied by using data and information concerning selected LOE and collected from monitoring programs and research studies carried out in the last 15 years in the lagoon of Venice. A set of sampling stations characterized by spatially and temporally

  2. Environmental Assessment for Beach Shoreline Protection at Patrick Air Force Base, Florida

    DTIC Science & Technology

    2012-02-27

    3) a Florida Panhandle nesting subpopulation, occurring at Eglin Air Force Base and the beaches near Panama City, Florida; (4) a Yucatan nesting...subpopulation, occurring on the Eastern Yucatan Peninsula, Mexico (Marquez 1990 and Turtle Expert Working Group or TEWG 2000); and (5) a Dry Tortugas...the Yucatan Peninsula. Additional important foraging areas in the western Atlantic include the Mosquito Lagoon and Indian River Lagoon systems and

  3. An Optimization of the Maintenance Assets Distribution Network in the Argentine Air Force

    DTIC Science & Technology

    2015-03-26

    Air Force (2010). Manual de Conduccion Logistica . Buenos Aires: HQ Argentine Air Force. Argentine Air Force (2012). El vuelo del condor: 1912-2012...recommendation was made to consider organic or private transportation and reduce transportation time in order to improve responsiveness and drive down...determine overall transportation demand and capacity required for a defined level of service, and to evaluate the tradeoffs between costs and service

  4. Radiological impact of phosphogypsum discharged into the Venice lagoon: 222Rn

    NASA Astrophysics Data System (ADS)

    Cantaluppi, C.; Ceccotto, F.; Cianchi, A.; Fasson, A.; Degetto, S.

    2012-04-01

    For about 20 years, between the 60 's and the 80 's of the last century, in the Passo a Campalto area (Lagoon of Venice - Italy) about 400,000 m3 of phosphogypsum (PG) were deposited at the border of the lagoon and next to urban areas without any environmental control. These materials are a by-product formed during the wet processing of phosphate rocks by sulphuric acid and have a significant environmental impact due to their abundance and their chemical-physical and radiochemical characteristics. The PG contains both chemical elements, which are considered dangerous for the ecosystems and natural radionuclides whose concentrations are much higher if compared to those typical for the Earth's crust. These discarded materials caused for many years the dispersion of radionuclides in the environment due to the tidal erosion, the re-suspension of radioactive inhalable dusts, the uncontrolled radon exhalation and the bioaccumulation of some radionuclides in the lagoon environment. After a decision of the appointed authorities, the Venice Water Authority (Ministry of Infrastructure and Transport), planned a permanent safety control of the site resulting in the complete isolation of the entire volume of contaminated materials from the environmental system. The entire project was specific for the particular features of the site and it required the improvement of analytical, sampling and measurement techniques in order to verify the effectiveness of the safety action. The radon assessment, in particular the check of the effectiveness of the inhibition of radon exhalation, is part of a more complex study, covering many other aspects of the management of a permanent disposal; they will be the object of further notes. The ultimate results of this study prove the efficacy of the intervention: radon concentrations in air and exhalation values from the restored area, measured during surveys, have been proved to be well in agreement with those of non contaminated soils.

  5. Pilot-scale field study for ammonia removal from lagoon biogas using an acid wet scrubber.

    PubMed

    Lin, Hongjian; Wu, Xiao; Miller, Curtis; Zhu, Jun; Hadlocon, Lara Jane; Manuzon, Roderick; Zhao, Lingying

    2014-01-01

    The anaerobic activities in swine slurry storage and treatment generate biogas containing gaseous ammonia component which is a chemical agent that can cause adverse environmental impacts when released to the atmosphere. The aim of this pilot plant study was to remove ammonia from biogas generated in a covered lagoon, using a sulfuric acid wet scrubber. The data showed that, on average, the biogas contained 43.7 ppm of ammonia and its concentration was found to be exponentially related to the air temperature inside the lagoon. When the air temperature rose to 35°C and the biogas ammonia concentration reached 90 ppm, the mass transfer of ammonia/ammonium from the deeper liquid body to the interface between the air and liquid became a limiting factor. The biogas velocity was critical in affecting ammonia removal efficiency of the wet scrubber. A biogas flow velocity of 8 to 12 mm s(-1) was recommended to achieve a removal efficiency of greater than 60%. Stepwise regression revealed that the biogas velocity and air temperature, not the inlet ammonia concentration in biogas, affected the ammonia removal efficiency. Overall, when 73 g L(-1) (or 0.75 M) sulfuric acid solution was used as the scrubber solution, removal efficiencies varied from 0% to 100% with an average of 55% over a 40-d measurement period. Mass balance calculation based on ammonium-nitrogen concentration in final scrubber liquid showed that about 21.3 g of ammonia was collected from a total volume of 1169 m(3) of biogas, while the scrubber solution should still maintain its ammonia absorbing ability until its concentration reaches up to 1 M. These results showed promising use of sulfuric acid wet scrubber for ammonia removal in the digester biogas.

  6. Interannual and cyclone-driven variability in phytoplankton communities of a tropical coastal lagoon.

    PubMed

    Srichandan, Suchismita; Kim, Ji Yoon; Kumar, Abhishek; Mishra, Deepak R; Bhadury, Punyasloke; Muduli, Pradipta R; Pattnaik, Ajit K; Rastogi, Gurdeep

    2015-12-15

    One of the main challenges in phytoplankton ecology is to understand their variability at different spatiotemporal scales. We investigated the interannual and cyclone-derived variability in phytoplankton communities of Chilika, the largest tropical coastal lagoon in Asia and the underlying mechanisms in relation to environmental forcing. Between July 2012 and June 2013, Cyanophyta were most prolific in freshwater northern region of the lagoon. A category-5 very severe cyclonic storm (VSCS) Phailin struck the lagoon on 12th October 2013 and introduced additional variability into the hydrology and phytoplankton communities. Freshwater Cyanophyta further expanded their territory and occupied the northern as well as central region of the lagoon. Satellite remote sensing imagery revealed that the phytoplankton biomass did not change much due to high turbidity prevailing in the lagoon after Phailin. Modeling analysis of species-salinity relationship identified specific responses of phytoplankton taxa to the different salinity regime of lagoon. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Microbiological and serological control of Escherichia coli O157: H7 in kindergarten staff in Buenos Aires city and suburban areas.

    PubMed

    Fernández-Brando, Romina J; Amaral, María Marta; Ciocchini, Andrés E; Bentancor, Leticia V; Trelles, Jorge A; Da Rocha, Marcelo; Landriel, Martín; Ugarte, Mariana; Briones, Gabriel; Ibarra, Cristina; Palermo, Marina S

    2017-01-01

    Shiga toxin (Stx)-producing Escherichia coli (STEC) infections are implicated in the development of the life-threatening hemolytic-uremic syndrome (HUS). Despite the magnitude of the social and economic problems caused by HUS, no licensed vaccine or effective therapy is currently available for human use. Prevention of STEC infections continues being the most important measure to reduce HUS incidence. This is especially true for Argentina where HUS incidence among children is extremely high and shows an endemic pattern. The aim of this work was to investigate serologically adult staff of kindergartens in Buenos Aires city and suburban areas in order to detect possible carriers, and to educate personnel about good practices to reduce HUS transmission. We also assessed the microbiological quality of water and meal samples from the same kindergartens. We tested 67 healthy adults, 13 water supplies and 6 meals belonging to 6 public kindergartens. We analysed hand swabs for isolation of STEC and serum samples for the presence of antibodies against Stx and lipopolysaccharide (LPS) of O157 serogroup. We identified 46 Stx2-positive individuals, but only 7 for O157 LPS. No presence of STEC pathogens was detected in hands of staff, water or meal samples.

  8. Cross-Cultural Adaptation of a Text Message-Based Program for Smoking Cessation in Buenos Aires, Argentina.

    PubMed

    Colantonio, Lisandro D; Peña, Lorena; Whittaker, Robyn; Mejia, Raul M

    2016-03-01

    Few individual-level nonpharmacological interventions are available in Argentina to support smokers who attempt to quit. We conducted a cross-cultural adaptation of Stop Smoking with Mobile Phones, an English text message-based tobacco cessation program, in Buenos Aires. The process included English-Spanish translation and back-translation, face validity checking by two local tobacco cessation experts, and a complete review using a structured questionnaire and discussion groups with potential users (current smokers who want to quit or former smokers who quit in the past 6 months). An editing group was responsible for analyzing information collected and preparing adapted messages. Readability of final messages was assessed. Tobacco cessation experts found translated messages suitable for the local setting, although mention of "mate" (a local infusion which can trigger cravings) was recommended. Review of messages by two potential users confirmed most of the messages would help smokers to quit and resulted in minor edits. Potential users who participated in two discussion groups (n = 17, 64.7% female, age range: 30-73) found the content of messages was relevant for cessation and related to their own experiences, although they suggested adding information regarding the negative consequences of smoking. Participants emphasized that messages should be formatted using voseo and informal style and provided feedback on specific words and expressions. Readability of final messages was easy/very easy (Fernández Huerta Index: 79.93). The cross-cultural adaptation of Stop Smoking with Mobile Phones resulted in relevant revisions for the study population, including tone, wording, and pertinent information (eg, smoking consequences). Local acceptability and effectiveness should be confirmed in future studies. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e

  9. Dynamics of copper and zinc sedimentation in a lagooning system receiving landfill leachate.

    PubMed

    Guigue, Julien; Mathieu, Olivier; Lévêque, Jean; Denimal, Sophie; Steinmann, Marc; Milloux, Marie-Jeanne; Grisey, Hervé

    2013-11-01

    This study characterises the sediment dredged from a lagooning system composed of a settling pond and three lagoons that receive leachates from a municipal solid waste (MSW) landfill in France. Organic carbon, carbonate, iron oxyhydroxides, copper (Cu) and zinc (Zn) concentrations were measured in the sediment collected from upstream to downstream in the lagooning system. In order to complete our investigation of sedimentation mechanisms, leachates were sampled in both dry (spring) and wet (winter) seasonal conditions. Precipitation of calcite and amorphous Fe-oxyhydroxides and sedimentation of organic matter occurred in the settling pond. Since different distributions of Zn and Cu concentrations are measured in sediment samples collected downstream in the lagooning system, it is suggested that these elements were not distributed in a similar way in the leachate fractions during the first stage of treatment in the settling pond, so that their sedimentation dynamics in the lagooning system differ. In the lagoons, it was found that organic carbon plays a major role in Cu and Zn mobility and trapping. The presence of macrophytes along the edges provided an input of organic matter that enhanced Cu and Zn scavenging. This edge effect resulted in a two-fold increase in Cu and Zn concentrations in the sediment deposited near the banks of the lagoons, thus confirming the importance of vegetation for the retention of Cu and Zn in lagooning systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Temporal stability of otolith elemental fingerprints discriminates among lagoon nursery habitats

    NASA Astrophysics Data System (ADS)

    Tournois, Jennifer; Ferraton, Franck; Velez, Laure; McKenzie, David J.; Aliaume, Catherine; Mercier, Lény; Darnaude, Audrey M.

    2013-10-01

    The chemical composition of fish otoliths reflects that of the water masses that they inhabit. Otolith elemental compositions can, therefore, be used as natural tags to discriminate among habitats. However, for retrospective habitat identification to be valid and reliable for any adult, irrespective of its age, significant differences in environmental conditions, and therefore otolith signatures, must be temporally stable within each habitat, otherwise connectivity studies have to be carried out by matching year-classes to the corresponding annual fingerprints. This study investigated how various different combinations of chemical elements in otoliths could distinguish, over three separate years, between four coastal lagoon habitats used annually as nurseries by gilthead sea bream (Sparus aurata L.) in the Gulf of Lions (NW Mediterranean). A series of nine elements were measured in otoliths of 301 S. aurata juveniles collected in the four lagoons in 2008, 2010 and 2011. Percentages of correct re-assignment of juveniles to their lagoon of origin were calculated with the Random Forest classification method, considering every possible combination of elements. This revealed both spatial and temporal variations in accuracy of habitat identification, with correct re-assignment to each lagoon ranging from 44 to 99% depending on the year and the lagoon. There were also annual differences in the combination of elements that provided the best discrimination among the lagoons. Despite this, when the data from the three years were pooled, a combination of eight elements (B, Ba, Cu, Li, Mg, Rb, Sr and Y) provided greater than 70% correct re-assignment to each single lagoon, with a multi-annual global accuracy of 79%. When considering the years separately, discrimination accuracy with these elemental fingerprints was above 90% for 2008 and 2010. It decreased to 61% in 2011, when unusually heavy rainfall occurred, which presumably reduced chemical differences among several of the

  11. Biogeochemical responses of shallow coastal lagoons to Climate Change

    NASA Astrophysics Data System (ADS)

    Brito, A.; Newton, A.; Tett, P.; Fernandes, T.

    2009-04-01

    The importance of climate change and global warming in the near future is becoming consensual within the scientific community (e.g. Kerr et al., 2008; Lloret et al., 2008). The surface temperature and sea level have increased during the last few years in the northern hemisphere (IPCC, 2007). Predictions for future changes include an increase of surface temperature and sea level for Europe. Moreover, the global warming phenomenon will also change the hydrological cycle and increase precipitation in northern and central Europe (IPCC, 2007). Sea level rise already threatens to overwhelm some lagoons, such as Venice and Moroccan lagoons (Snoussi et al., 2008). Shallow coastal lagoons are some of the most vulnerable systems that will be impacted by these changes (Eisenreich, 2005). Environmental impacts on coastal lagoons include an increase of water turbidity and therefore light attenuation. If these effects are strong enough, the lighted bottoms of shallow lagoons may loose a significant part of the benthic algal community. These communities are highly productive and are essential to control nutrient dynamics of the system by uptaking large amounts of nutrients both from the water column and from the sediments. A decrease in benthic algal communities and photosynthetic oxygen production will also contribute to increasing the vulnerability of the lagoons to hypoxia and anoxia. The flux of nutrients such as phosphate from the sediments may increase dramatically, further disrupting the nutrient balance and condition and promoting cyanobacterial blooms. Microbial activity is temperature dependent, therefore, the increase of temperature will increase the concentrations of ammonium within sediments. The release of phosphate and silicate will also increase with temperature. Coastal lagoons are valuable ecosystems and may be severely impacted, both ecologically and economically, by global change. Shallow coastal lagoons should be considered as sentinel systems and should be

  12. LANDSAT imagery of the Venetian Lagoon: A multitemporal analysis

    NASA Technical Reports Server (NTRS)

    Alberotanza, L.; Zandonella, A. (Principal Investigator)

    1980-01-01

    The use of LANDSAT multispectral scanner images from 1975 to 1979 to determine pollution dispersion in the central basin of the lagoon under varying tidal conditions is described. Images taken during the late spring and representing both short and long range tidal dynamics were processed for partial haze removal and removal of residual striping. Selected spectral bands were correlated to different types of turbid water. The multitemporal data was calibrated, classified considering sea truth data, and evaluated. The classification differentiated tide diffusion, algae belts, and industrial, agricultural, and urban turbidity distributions. Pollution concentration is derived during the short time interval between inflow and outflow and from the distance between the two lagoon inlets and the industrial zones. Increasing pollution of the lagoon is indicated.

  13. Phylogenetic and phylodynamic analyses of human metapneumovirus in Buenos Aires (Argentina) for a three-year period (2009-2011).

    PubMed

    Velez Rueda, Ana Julia; Mistchenko, Alicia Susana; Viegas, Mariana

    2013-01-01

    Human metapneumovirus, which belongs to the Paramyxoviridae family and has been classified as a member of the Pneumovirus genus, is genetically and clinically similar to other family members such as human respiratory syncytial virus. A total of 1146 nasopharyngeal aspirates from pediatric patients with moderate and severe acute lower respiratory tract infections, hospitalized at the Ricardo Gutierrez Childreńs Hospital (Buenos Aires, Argentina), were tested by real time RT-PCR for human metapneumovirus. Results showed that 168 (14.65%) were positive. Thirty-six of these 168 samples were randomly selected to characterize positive cases molecularly. The phylogenetic analysis of the sequences of the G and F genes showed that genotypes A2 and B2 cocirculated during 2009 and 2010 and that only genotype A2 circulated in 2011 in Argentina. Genotype A2 prevailed during the study period, a fact supported by a higher effective population size (Neτ) and higher diversity as compared to that of genotype B2 (10.9% (SE 1.3%) vs. 1.7% (SE 0.4%), respectively). The phylogeographic analysis of the G protein gene sequences showed that this virus has no geographical restrictions and can travel globally harbored in hosts. The selection pressure analysis of the F protein showed that although this protein has regions with polymorphisms, it has vast structural and functional constraints. In addition, the predicted B-linear epitopes and the sites recognized by previously described monoclonal antibodies were conserved in all Argentine sequences. This points out this protein as a potential candidate to be the target of future humanized antibodies or vaccines.

  14. Eutrophication Process on Coastal Lagoons of North of Sinaloa, Mexico

    NASA Astrophysics Data System (ADS)

    Escobedo-Urias, D.; Martinez-Lopez, A.

    2007-05-01

    Coastal ecosystems in the Gulf of California support diverse and important fisheries and are reservoirs of great biological diversity. In northern Sinaloa, population growth and development, as well as increased use of these natural systems for recreation, has substantially increased the pressure placed upon marine resources. Discharge of untreated wastewaters generated by diverse human activities has been notably altered its health and integrity, principally along the lagoon's eastern shore In the late 60s, agriculture moved into a dominant role in coastal northern Sinaloa. The coastal plain encompasses more than 200,000 hectares under cultivation that now introduces large amounts of organic material, pesticides, heavy metals, and fertilizers into the lagoon systems of Topolobampo and San Ignacio-Navachiste-Macapule System at drainage discharge points and a minor grade in Colorado Lagoon. These lagoons are shallow and exhibit low water quality, lost of lagoon depth, presence of toxic substances (heavy metals) near the discharge points of wastewaters, and presence of harmful algal blooms. With the aim of evaluate the nutrients loadings (wastewaters, groundwaters) and their effects on the coastal lagoons of north of Sinaloa, the preliminary analysis of the physical, chemical and biologic variables data series are analyzed. From 1987-2007 eutrophication process is identified in Topolobampo Complex show increase tendency in annual average concentrations of DIN (Dissolved Inorganic Nitrogen= NO2+NO3) from 0.5 μ M in 1987 to 2.7 μ M in 2006. Trophic Index (TRIX) values, low nutrient ratios (N: P and N: Si) and the phytoplanktonic community structure support this result. Preliminary results of nutrients loadings show a mayor contribution of wastewaters into the coastal zone.

  15. Copper complexation capacity in surface waters of the Venice Lagoon.

    PubMed

    Delgadillo-Hinojosa, Francisco; Zirino, Alberto; Nasci, Cristina

    2008-10-01

    Total copper (Cu(T)), copper ion activity (pCu) and the copper complexation capacity (CuCC) were determined in samples of seawater collected in July 2003 from the Venice Lagoon. Cu(T) and CuCC showed considerable spatial variability: Cu(T) ranged from 1.8 to 70.0nM, whereas the CuCC varied from 195 to 573nM. pCu values varied from 11.6 to 12.6 and are consistent with those previously reported in estuarine and coastal areas (10.9-14.1). The range of Cu(T) values compares well with those reported in the past in the lagoon and in the adjacent Adriatic Sea. The highest concentrations of Cu(T) were found in samples collected near the industrial area of Porto Marghera, whereas the lowest were measured near the Chioggia and Malamocco inlets, where an intense tidally-driven renewal of seawater takes place. Although CuCC showed a high degree of spatial variability, the values recorded in the Venice Lagoon are comparable to those reported in other estuarine systems. In addition, CuCC was positively correlated with dissolved organic carbon (DOC), suggesting that organic ligands responsible for Cu complexation are part of the bulk organic matter pool in the lagoon. The CuCC:Cu(T) molar ratio was, on average 55:1, indicating that a large excess of complexation capacity exists in the Venice Lagoon. The high levels of CuCC and the narrow range of pCu indicates the importance of the role played by organic ligands in controlling the free ion Cu concentrations in the lagoon, and as a consequence, regulating its availability and/or toxicity.

  16. Hydrology and Salt Balance in a Large, Hypersaline Coastal Lagoon: Lagoa de Araruama, Brazil

    NASA Astrophysics Data System (ADS)

    Kjerfve, Björn; Schettini, C. A. F.; Knoppers, Bastiaan; Lessa, Guilherme; Ferreira, H. O.

    1996-06-01

    Lagoa de Araruama in the state of Rio de Janeiro, Brazil, is a hypersaline coastal lagoon as a result of semi-arid climate conditions, a small drainage basin and a choked entrance channel. The lagoon has been continuously hypersaline for at least 4·5 centuries, but the mean salinity has varied substantially. It has recently decreased from 57 to 52 as indicated by density (salinity) measurements between 1965 and 1990. Analysis of more than 20 years of salinity time series data, in addition to monthly lagoon cruises to measure the spatial salinity distribution, indicate that the lagoon salinity largely fluctuates in response to the difference between evaporation and precipitation. The major factor explaining the long-term trend of decreasing salinity in the lagoon is the constant pumping of 1 m 3s -1of freshwater to the communities surrounding the lagoon from an adjacent watershed, and subsequent discharge of this water into Lagoa de Araruama. The net salt budget is primarily a balance between the advective import of salt from the coastal ocean and eddy diffusive export of salt to the ocean, although the extensive mining of salt from the lagoon during past decades is also a small but significant contribution to the salt budget. The flushing half-life is proposed as a useful time scale of water exchange, is calculated based on a combination of hydrological and tidal processes, and is excellent for comparison of lagoons and assessing water quality changes. The flushing half-life measures 83·5 days for Lagoa de Araruama, considerably longer than for most other coastal lagoons. The proposed dredging of a second ocean channel to Lagoa de Araruama is probably not a good idea. It is likely to accelerate the decrease of lagoon salinity and somewhat improve the lagoon water exchange. At the same time, this will eliminate the apparent buffering capacity provided by the hypersaline environment, and thus may potentially cause water quality problems.

  17. Consistency of temporal and habitat-related differences among assemblages of fish in coastal lagoons

    NASA Astrophysics Data System (ADS)

    Gray, Charles A.; Rotherham, Douglas; Johnson, Daniel D.

    2011-12-01

    The consistency of habitat-related differences in coastal lagoon fish assemblages was assessed across different spatial and temporal scales. Multimesh gillnets were used to sample assemblages of fish on a monthly basis for 1-year in three habitats (shallow seagrass, shallow bare and deep substrata) at two locations (>1 km apart), in each of two coastal lagoons (approximately 500 km apart), in southeastern Australia. A total of 48 species was sampled with 34 species occurring in both lagoons and in all three habitats; species caught in only one lagoon or habitat occurred in low numbers. Ten species dominated assemblages and accounted for more than 83% of all individuals sampled. In both lagoons, assemblages in the deep habitat consistently differed to those in the shallow strata (regardless of habitat). Several species were caught more frequently or in larger numbers in the deep habitat. Assemblages in the two shallow habitats did not differ consistently and were dominated by the same species and sizes of fish, possibly due to habitat heterogeneity and the scale and method of sampling. Within each lagoon, very few between location differences in assemblages within each habitat were observed. Consistent differences in assemblages were detected between lagoons for the shallow bare and deep habitats, indicating there were some intrinsic differences in ichthyofauna between lagoons. Assemblages in spring differed to those in summer, which differed to those in winter for the shallow bare habitat in both lagoons, and the deep habitat in only one lagoon. Fish-habitat relationships are complex and differences in the fish fauna between habitats were often temporally inconsistent. This study highlights the need for greater testing of habitat relationships in space and time to assess the generality of observations and to identify the processes responsible for structuring assemblages.

  18. Sustainability assessment of traditional fisheries in Cau Hai lagoon (South China Sea).

    PubMed

    Marconi, Michele; Sarti, Massimo; Marincioni, Fausto

    2010-01-01

    Overfishing and progressive environmental degradation of the Vietnamese Cau Hai coastal lagoon appear to be threatening the ecological integrity and water quality of the largest estuarine complex of Southeast Asia. This study assessed the relationships between the density of traditional fisheries and organic matter sedimentary contents in Cau Hai lagoon. Data revealed that the density of stake traps (the most common fishing gear used in this lagoon), decreasing hydrodynamic energy in shallow water, causes the accumulation of a large fraction of organic matter refractory to degradation. The relationship between biopolymeric carbon (a proxy of availability of organic matter) and stake traps density fits a S-shape curve. The logistic equation calculated a stake traps density of 90 m of net per hectare, as the threshold over which maximum accumulation of organic matter occurs in Cau Hai. With such level of stake trap density, and assuming a theoretical stationary status of the lagoon, the time necessary for the system to reach hypoxic conditions has been calculated to be circa three weeks. We recommend that this density threshold should not be exceeded in the Cau Hai lagoon and that further analyses of organic loads in the sediment should be conducted to monitor the trophic conditions of this highly eutrophicated lagoon. 2010 Elsevier Ltd. All rights reserved.

  19. Microbial community analysis of swine wastewater anaerobic lagoons by next-generation DNA sequencing.

    PubMed

    Ducey, Thomas F; Hunt, Patrick G

    2013-06-01

    Anaerobic lagoons are a standard practice for the treatment of swine wastewater. This practice relies heavily on microbiological processes to reduce concentrated organic material and nutrients. Despite this reliance on microbiological processes, research has only recently begun to identify and enumerate the myriad and complex interactions that occur in this microbial ecosystem. To further this line of study, we utilized a next-generation sequencing (NGS) technology to gain a deeper insight into the microbial communities along the water column of four anaerobic swine wastewater lagoons. Analysis of roughly one million 16S rDNA sequences revealed a predominance of operational taxonomic units (OTUs) classified as belonging to the phyla Firmicutes (54.1%) and Proteobacteria (15.8%). At the family level, 33 bacterial families were found in all 12 lagoon sites and accounted for between 30% and 50% of each lagoon's OTUs. Analysis by nonmetric multidimensional scaling (NMS) revealed that TKN, COD, ORP, TSS, and DO were the major environmental variables in affecting microbial community structure. Overall, 839 individual genera were classified, with 223 found in all four lagoons. An additional 321 genera were identified in sole lagoons. The top 25 genera accounted for approximately 20% of the OTUs identified in the study, and the low abundances of most of the genera suggests that most OTUs are present at low levels. Overall, these results demonstrate that anaerobic lagoons have distinct microbial communities which are strongly controlled by the environmental conditions present in each individual lagoon. Published by Elsevier Ltd.

  20. Future evolution of a tidal inlet due to changes in wave climate, Sea level and lagoon morphology (Óbidos lagoon, Portugal)

    NASA Astrophysics Data System (ADS)

    Bruneau, Nicolas; Fortunato, André B.; Dodet, Guillaume; Freire, Paula; Oliveira, Anabela; Bertin, Xavier

    2011-11-01

    Tidal inlets are extremely dynamic, as a result of an often delicate balance between the effects of tides, waves and other forcings. Since the morphology of these inlets can affect navigation, water quality and ecosystem dynamics, there is a clear need to anticipate their evolution in order to promote adequate management decisions. Over decadal time scales, the position and size of tidal inlets are expected to evolve with the conditions that affect them, for instance as a result of climate change. A process-based morphodynamic modeling system is validated and used to analyze the effects of sea level rise, an expected shift in the wave direction and the reduction of the upper lagoon surface area by sedimentation on a small tidal inlet (Óbidos lagoon, Portugal). A new approach to define yearly wave regimes is first developed, which includes a seasonal behavior, random inter-annual variability and the possibility to extrapolate trends. Once validated, this approach is used to produce yearly time series of wave spectra for the present and for the end of the 21st century, considering the local rotation trends computed using hindcast results for the past 57 years. Predictions of the mean sea level for 2100 are based on previous studies, while the bathymetry of the upper lagoon for the same year is obtained by extrapolation of past trends. Results show, and data confirm, that the Óbidos lagoon inlet has three stable configurations, largely determined by the inter-annual variations in the wave characteristics. Both sea level rise and the reduction of the lagoon surface area will promote the accretion of the inlet. In contrast, the predicted rotation of the wave regime, within foreseeable limits, will have a negligible impact on the inlet morphology.

  1. Estimating Emissions of Ammonia and Methane from an Anaerobic Livestock Lagoon Using Micrometeorological Methods and Inverse Modeling

    NASA Astrophysics Data System (ADS)

    Shonkwiler, K. B.; Ham, J. M.; Williams, C.

    2012-12-01

    Evaluating the impact of increased carbon and nitrogen emissions on local air quality and regional bionetworks due to animal agricultural activity is of great interest to the public, political, economic and ecological welfare of areas within the scope of these practices. Globally, livestock operations account for 64% of annual anthropogenic emissions of ammonia (NH3) [1]. Concerning methane (CH4), anaerobic lagoons from commercial dairy operations contribute the second largest share of CH4 emissions from manure in the United States[1], and additionally are a local source of NH3 as well. Anaerobic lagoons are commonly used in commercial animal agriculture and as significant local sources of greenhouse gases (GHG), there is a strong need to quantify GHG emissions from these systems. In 2012 at a commercial dairy operation in Northern Colorado, USA, measurements of CH4 were made using eddy covariance (EC), while NH3 was estimated using a combination of real-time monitoring (cavity ring-down spectroscopy as well as time-integrated passive samplers). Methane emissions have been measured at this lagoon using EC since 2011, with fluxes ranging from 0.5 mg m-2 s-1 in early summer to >2 mg m-2 s-1 in late summer and early fall. Concentration data of both CH4 and NH3 were used to estimate emissions using a 2-dimensional inverse model based on solving the advection-diffusion equation[2]. In the case of the CH4-EC data, results from the inverse model were compared with the EC-derived flux estimates for enhanced parameterization of surface geometry within the lagoon environment. The model was then applied using measured NH3 concentrations to achieve emissions estimates. While NH3 fluxes from the lagoon tend to be much lower than those of CH4 by comparison, modeling emissions of NH3 from the simple geometry of a lagoon will assist in applying the model to more complex surfaces. [1] FAO, 2006. Livestock's long shadow: Environmental issues and options. Livestock, Environment, and

  2. Groundwater and porewater as a major source of alkalinity to a fringing coral reef lagoon (Muri Lagoon, Cook Islands)

    NASA Astrophysics Data System (ADS)

    Cyronak, T.; Santos, I. R.; Erler, D. V.; Eyre, B. D.

    2012-11-01

    To better predict how ocean acidification will affect coral reefs, it is important to understand how biogeochemical cycles on reefs alter carbonate chemistry over various temporal and spatial scales. This study quantifies the contribution of fresh groundwater discharge (as traced by radon) and shallow porewater exchange (as quantified from advective chamber incubations) to total alkalinity (TA) dynamics on a fringing coral reef lagoon along the southern Pacific island of Rarotonga over a tidal and diel cycle. Benthic alkalinity fluxes were affected by the advective circulation of water through permeable sediments, with net daily flux rates of carbonate alkalinity ranging from -1.55 to 7.76 mmol m-2 d-1, depending on the advection rate. Submarine groundwater discharge (SGD) was a source of TA to the lagoon, with the highest flux rates measured at low tide, and an average daily TA flux of 1080 mmol m-2 d-1. Both sources of TA were important on a reef wide basis, although SGD acted solely as a delivery mechanism of TA to the lagoon, while porewater advection was either a sink or source of TA dependant on the time of day. On a daily basis, groundwater can contribute approximately 70% to 80% of the TA taken up by corals within the lagoon. This study describes overlooked sources of TA to coral reef ecosystems that can potentially alter water-column carbonate chemistry. We suggest that porewater and groundwater fluxes of TA should be taken into account in ocean acidification models in order to properly address changing carbonate chemistry within coral reef ecosystems.

  3. [Distribution of dental caries and its association with variables of social protection in children 12 years of age in the county of Avellaneda, Province of Buenos Aires].

    PubMed

    Fort, Adriana; Fuks, Aida Julia; Napoli, Alberto Vicente; Palomba, Silvia; Pazos, Ximena; Salgado, Pablo; Klemonskis, Graciela; Squassi, Aldo

    2017-01-01

    Different international organizations have indicated the need to analyze the conditions of each population in order to identify groups and individuals at risk as an operational strategy in pursuit of greater equity, efficacy and efficiency in the health system. The aim of this study was to identify differentials in the dental caries profiles of children attending public schools in the county of Avellaneda (Province of Buenos Aires, Argentina) and their association with variables of social protection. In 2014, an observational, analytical and cross-sectional study was performed with a sample of 656 students 12 years of age from 40 public schools in the 8 county districts (out of a total universe of 3580 individuals distributed in 70 schools). The dental status of 12-year-old schoolchildren living in the localities evaluated showed an unequal distribution; sub-groups with high caries prevalence, morbidity and severity were identified, requiring the targeting of health interventions. An association between untreated disease and lack of social protection was observed.

  4. Residence times in a hypersaline lagoon: Using salinity as a tracer

    NASA Astrophysics Data System (ADS)

    Mudge, Stephen M.; Icely, John D.; Newton, Alice

    2008-04-01

    Generally the waters of the Ria Formosa Lagoon, Portugal have a short residence time, in the order of 0.5 days (Tett, P., Gilpin, L., Svendsen, H., Erlandsson, C.P., Larsson, U., Kratzer, S., Fouilland, E., Janzen, C., Lee, J., Grenz, C., Newton, A., Ferreira, J.G., Fernandes, T., Scory, S., 2003. Eutrophication and some European waters of restricted exchange. Continental Shelf Research 23, 1635-1671). This estimation is based on the measurements of currents and the modelling of water exchange at the outlets to the ocean. However, observations of the temperature and salinity in the inner channels imply that residence time is greater in these regions of the lagoon. To resolve this apparent contradiction, spatial measurements of the temperature and salinity were made with a meter for conductivity, temperature and depth along the principal channels of the western portion of the lagoon, with a sampling frequency of two per second. Evaporation rates of 5.4 mm day -1 were measured in a salt extraction pond adjacent to the lagoon and used to determine the residence time through salinity differences with the incoming seawater. In June 2004, the water flooding in from the ocean had an average salinity of 36.07 which contrasted with a maximum of 37.82 at mid ebb on a spring tide, corresponding to a residence time of >7 days; the mean residence time was 2.4 days. As the tide flooded into the channels, the existing water was advected back into the lagoon. Although there was a small amount of mixing with water from another inlet, the water body from the inner lagoon essentially remained distinct with respect to temperature and salinity characteristics. The residence time of the water was further prolonged at the junction between the main channels, where distinct boundaries were observed between the different water masses. As the water ebbed out, the shallow Western Channel was essentially isolated from the rest of the outer lagoon, and the water from this channel was forced

  5. Environmental forcing on the flux of organic-walled dinoflagellate cysts in recent sediments from a subtropical lagoon in the Gulf of California.

    PubMed

    Cuellar-Martinez, Tomasa; Alonso-Rodríguez, Rosalba; Ruiz-Fernández, Ana Carolina; de Vernal, Anne; Morquecho, Lourdes; Limoges, Audrey; Henry, Maryse; Sanchez-Cabeza, Joan-Albert

    2018-04-15

    To evaluate the relationship of changes in organic-walled dinoflagellate cyst (dinocyst) fluxes to sediments with environmental variables (air and sea surface temperatures, El Niño conditions, rainfall, and terrigenous index), cyst assemblages were analyzed in a 210 Pb-dated sediment core (~100years) from the pristine San José Lagoon (San José Island, SW Gulf of California). The dinocyst abundance ranged from 3784 to 25,108cystsg -1 and fluxes were of the order of 10 3 -10 4 cystscm -2 yr -1 . Lingulodinium machaerophorum, Polysphaeridium zoharyi and Spiniferites taxa accounted for 96% of the total dinocyst assemblages, and the abundances of these species increased towards the core surface. P. zoharyi fluxes increased from about 1965 onwards. Redundancy analyses, showed that mean minimum air temperature and terrigenous index were the key factors governing dinocyst fluxes. In this study, dinocyst fluxes of dominant taxa had responded to changes in climate-dependent environmental variables during the past ~20years; this may also be the case in other subtropical coastal lagoons. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Subtidal hydrodynamics in a tropical lagoon: A dimensionless numbers approach

    NASA Astrophysics Data System (ADS)

    Tenorio-Fernandez, L.; Valle-Levinson, A.; Gomez-Valdes, J.

    2018-01-01

    Observations in a tropical lagoon of the Yucatan peninsula motivated a non-dimensional number analysis to examine the relative influence of tidal stress, density gradients and wind stress on subtidal hydrodynamics. A two-month observation period in Chelem Lagoon covered the transition from the dry to the wet season. Chelem Lagoon is influenced by groundwater inputs and exhibits a main sub-basin (central sub-basin), a west sub-basin and an east sub-basin. Subtidal hydrodynamics were associated with horizontal density gradients that were modified seasonally by evaporation, precipitation, and groundwater discharge. A tidal Froude number (Fr0), a Wedderburn number (W), and a Stress ratio (S0) were used to diagnose the relative importance of dominant subtidal driving forces. The Froude number (Fr0) compares tidal forcing and baroclinic forcing through the ratio of tidal stress to longitudinal baroclinic pressure gradient. The Wedderburn number (W) relates wind stress to baroclinicity. The stress ratio (S0) sizes tidal stress and wind stress. S0 is a new diagnostic tool for systems influenced by tides and winds, and represents the main contribution of this research. Results show that spring-tide subtidal flows in the tropical lagoon had log(Fr0) ≫ 0 and log(S0) > 0 , i.e., driven mainly by tidal stresses (advective accelerations). Neap tides showed log(Fr0) ≪ 0 and log(S0) < 0) , i.e., flows driven by baroclinicity, especially at the lagoon heads of the east and west sub-basins. However, when the wind stress intensified over the lagoon, the relative importance of baroclinicity decreased and the wind stress controlled the dynamics (log(W) ≫ 0). Each sub-basin exhibited a different subtidal response, according to the dimensionless numbers. The response depended on the fortnightly tidal cycle, the location and magnitude of groundwater input, and the direction and magnitude of the wind stress.

  7. Spatial and temporal variation of water quality in the coastal lagoons of Sinaloa

    NASA Astrophysics Data System (ADS)

    Paez-Osuna, F.; Lopez-Aguiar, L. K.; Del Río-Chuljak, A.; Ruiz-Fernandez, A. C.

    2007-05-01

    The Mexican state of Sinaloa has 656 km of coastline and 221,600 ha of coastal lagoons, and is characterized by a high fishing and agriculture activity. It is well known that agricultural activities constitute a major factor affecting the water quality in the coastal waters. The current study focused on the 6 more important coastal lagoons of Sinaloa (Topolobampo-Ohuira-Santa María, Navachiste-San Ignacio-Macapule, Santa María-La Reforma, Altata-Ensenada del Pabellón, Ceuta and Teacapán-Agua Brava) with the aim to evaluate the water quality spatial and temporal variation at the lagoons (physico-chemical parameters, nutrients (N, P and Si), dissolved oxygen, total suspended solids and chlorophyll a) and to assess its eutrophication status. The water samples were collected in several stations at each lagoon (between 9 and 23 stations depending on the lagoon area) at low and high tides, during three different weather periods (dry-warm, rainy and dry-cold seasons) between May 2004 and April 2005. Mean concentrations of nutrients (μM), dissolved oxygen (mg/L) and chlorophyll a (mg/m3) obtained for each variable were comparable between lagoons (total N=51±45; total P= 2.5±1.5; Si=23±31; DO=6.7±1.8; Chll=1.7±1.9) although seasonal and spatial differences were observed at each lagoon. The nutrient concentrations measured fell in the typical concentration intervals for coastal lagoons; however, critical sampling points were identified and related to direct discharges of untreated effluents from municipal wastes, aquaculture farms and agriculture drain ditches.

  8. Histology and gametogenesis in Heleobia piscium (Cochliopidae) from the Multiple Use Reserve "Isla Martín García," Buenos Aires, Argentina.

    PubMed

    Martin, Stella Maris; Díaz, Ana C

    2016-01-01

    Heleobia piscium (d'Orbigny, 1835), a member of the Cochliopidae family found only in South America, is distributed from Entre Ríos, Delta del Paraná, and the littoral of the Río de la Plata down as far as to Punta Indio (Buenos Aires), the southernmost limit of the snail's geographical distribution. To date, little information is available regarding the reproductive cycle of species within this family either in Argentina or throughout South America. The present work analyzed the histology of the reproductive system of the gonochoric species H. piscium and determined the stages oogenesis and spermatogenesis under natural conditions. Specimens of H. piscium were collected in the Multiple-Use Natural Reserve Isla Martín García, located in the Upper Río de la Plata estuary to the south of the mouth of the Uruguay River. The gametogenic cycle in both sexes was found to consist of the following stages: early maturation, maturation, and evacuation. The maturation period was found to extend from January to October and evacuation of the gametes to start in November and end in February (summer in the Southern Hemisphere). The results indicated the H. piscium exhibit a reproductive cycle without a resting period.

  9. Individual growth of Heleobia piscium in natural populations (Gastropoda: Cochliopidae) from the multiple use natural Reserve Isla Martin Garcia, Buenos Aires, Argentina.

    PubMed

    Martin, S M

    2008-08-01

    The present work analyses the individual growth of Heleobia piscium in natural conditions in coastal drainage channels of the Multiple Use Natural Reserve Isla Martín García, Buenos Aires, Argentina. Isla Martín García is located in the Upper Río de la Plata, to the south of the mouth of the Uruguay river (34 degrees 11' 25" S and 58 degrees 15' 38" W). Monthly collections were made from July 2005 to July 2006 in the eastern part of the island (Arena Beach). The population of H. piscium showed a complex and dynamic structure of sizes during a long period of the annual cycle. Two cohorts could be detected. The Bertalanffy growth equation was: Lt = 6 (1-e -1.85 (t+0.38)) and Lt = 3.9 (1-e -0.19 (t+4.84)) for cohorts 1 and 2, respectively. The pattern of population growth displayed a staggered model, where the greatest growth is observed during the summer. The reproductive period occurred during six months, from the beginning of summer to middle of fall. Based on only one reproductive effort, this pattern is not similar to that of other cogeneric species already studied.

  10. Distribution and stability of eelgrass beds at Izembek Lagoon, Alaska

    USGS Publications Warehouse

    Ward, David H.; Markon, Carl J.; Douglas, David C.

    1997-01-01

    Spatial change in eelgrass meadows, Zostera marina L., was assessed between 1978 and 1987 and between 1987 and 1995 at Izembek Lagoon, Alaska. Change in total extent was evaluated through a map to map comparison of data interpreted from a 1978 Landsat multi-spectral scanner image and 1987 black and white aerial photographs. A ground survey in 1995 was used to assess spatial change from 1987. Eelgrass beds were the predominant vegetation type in the lagoon, comprising 44-47% (15000-16000 ha) of the total area in 1978 and 1987. Izembek Lagoon contains the largest bed of seagrass along the Pacific Coast of North America and largest known single stand of eelgrass in the world. There was a high degree of overlap in the spatial distribution of eelgrass among years of change detection. The overall net change was a 6% gain between, 1978 and 1987 and a <1% gain between 1987 and 1995. The lack of significant change in eelgrass cover suggests that eelgrass meadows in Izembek Lagoon have been stable during the 17-year period of our study.

  11. The high resolution mapping of the Venice Lagoon tidal network

    NASA Astrophysics Data System (ADS)

    Madricardo, Fantina; Foglini, Federica; Kruss, Aleksandra; Bellafiore, Debora; Trincardi, Fabio

    2017-04-01

    One of the biggest challenges of the direct observation of the ocean is to achieve a high resolution mapping of its seafloor morphology and benthic habitats. So far, sonars have mapped just 0.05% of the ocean floor with less than ten-meter resolution. The recent efforts of the scientific community have been devoted towards the mapping of both Deep Ocean and very shallow coastal areas. Coastal and transitional environments in particular undergo strong morphological changes due to natural and anthropogenic pressure. Nowadays, only about 5% of the seafloor of these environments † have been mapped: the shallowness of these environments has prevented the use of underwater acoustics to reveal their morphological features. The recent technological development of multibeam echosounder systems, however, enables these instruments to achieve very high performances also in such shallow environments. In this work, we present results and case studies of an extensive multibeam survey carried out in the Lagoon of Venice in 2013. The Lagoon of Venice is the biggest lagoon in the Mediterranean Sea with a surface of about 550 km2 and with an average depth of about 1 m. In the last century, the morphological and ecological properties of the lagoon changed dramatically: the surface of the salt marshes was reduced by 60% and some parts of the lagoon are deepening with a net sediment flux exiting from the inlets. Moreover, major engineering interventions are currently ongoing at the inlets (MOSE project). These changes at the inlets could affect substantially the lagoon environment. To understand and monitor the future evolution of the Lagoon of Venice, ISMAR within the project RITMARE (a National Research Programme funded by the Italian Ministry of University and Research) carried out an extensive survey, involving a team of more than 25 scientists, to collect high resolution (0.5 m) bathymetry of key study areas such as the tidal inlets and channels. Following a broad

  12. Aspects of fish conservation in the upper Patos Lagoon basin.

    PubMed

    Fontoura, N F; Vieira, J P; Becker, F G; Rodrigues, L R; Malabarba, L R; Schulz, U H; Möller, O O; Garcia, A M; Vilella, F S

    2016-07-01

    The Patos Lagoon basin is a large (201 626 km(2) ) and complex drainage system in southern Brazil. The lagoon is 250 km long and 60 km wide, covering an area of 10 360 km(2) . The exchange of water with the Atlantic Ocean occurs through a 0·8 km wide and 15 m deep inlet, fixed by 4 km long jetties, at the southernmost part of the Patos Lagoon. The estuarine area is restricted to its southern portion (10%), although the upper limit of saline waters migrates seasonally and year to year, influenced by the wind regime and river discharge. The known number of recorded limnetic fish species is 200, but this number is expected to increase. A higher endemism is observed in fish species occurring in upper tributaries. The basin suffers from the direct impact of almost 7 million inhabitants, concentrated in small to large cities, most with untreated domestic effluents. There are at least 16 non-native species recorded in natural habitats of the Patos Lagoon basin, about half of these being from other South American river basins. Concerning the fishery, although sport and commercial fisheries are widespread throughout the Patos Lagoon basin, the lagoon itself and the estuarine area are the main fishing areas. Landing statistics are not available on a regular basis or for the whole basin. The fishery in the northern Patos Lagoon captures 31 different species, nine of which are responsible for most of the commercial catches, but only three species are actually sustaining the artisanal fishery: the viola Loricariichthys anus: 455 kg per 10 000 m(2) gillnet per day, the mullet Mugil liza: 123 kg per 10 000 m(2) gillnet per day and the marine catfish Genidens barbus: 50 kg per 10 000 m(2) gillnet per day. A decline of the fish stocks can be attributed to inadequate fishery surveillance, which leads to overfishing and mortality of juveniles, or to decreasing water quality because of urban and industrial activities and power production. Global climatic changes also represent a

  13. Marshall Islands Fringing Reef and Atoll Lagoon Observations of the Tohoku Tsunami

    NASA Astrophysics Data System (ADS)

    Ford, Murray; Becker, Janet M.; Merrifield, Mark A.; Song, Y. Tony

    2014-12-01

    The magnitude 9.0 Tohoku earthquake on 11 March 2011 generated a tsunami which caused significant impacts throughout the Pacific Ocean. A description of the tsunami within the lagoons and on the surrounding fringing reefs of two mid-ocean atoll islands is presented using bottom pressure observations from the Majuro and Kwajalein atolls in the Marshall Islands, supplemented by tide gauge data in the lagoons and by numerical model simulations in the deep ocean. Although the initial wave arrival was not captured by the pressure sensors, subsequent oscillations on the reef face resemble the deep ocean tsunami signal simulated by two numerical models, suggesting that the tsunami amplitudes over the atoll outer reefs are similar to that in deep water. In contrast, tsunami oscillations in the lagoon are more energetic and long lasting than observed on the reefs or modelled in the deep ocean. The tsunami energy in the Majuro lagoon exhibits persistent peaks in the 30 and 60 min period bands that suggest the excitation of closed and open basin normal modes, while energy in the Kwajalein lagoon spans a broader range of frequencies with weaker, multiple peaks than observed at Majuro, which may be associated with the tsunami behavior within the more irregular geometry of the Kwajalein lagoon. The propagation of the tsunami across the reef flats is shown to be tidally dependent, with amplitudes increasing/decreasing shoreward at high/low tide. The impact of the tsunami on the Marshall Islands was reduced due to the coincidence of peak wave amplitudes with low tide; however, the observed wave amplitudes, particularly in the atoll lagoon, would have led to inundation at different tidal phases.

  14. [The case of the 'lowlife': perceptions of danger and the prevention of disreputable behaviors in theRevista de Criminología, Psiquiatría, Medicina Legal y Ciencias Afinesin Buenos Aires, 1914-1923].

    PubMed

    Dovio, Mariana

    2013-11-30

    We analyze the construction of the notion of the 'lowlife' in the city of Buenos Aires in the Revista de Criminología, Psiquiatría y Medicina Legal, from 1914-1923. We shall analyze the notion of 'lowlife', meaning behaviors situated in a border zone between crime and madness, from the point of view of prevention and perception of danger. The first way of analyzing the 'lowlife' examines institutional projects that were related to eugenics and that advocated preventive detention of dangerous people, 'alcoholists' and vagrants. The second involves identifying in moral and physical terms the kind of people who were targeted in the creation of intervention projects for those considered to be 'lowlifes', who could potentially damage the fabric of society in some way.

  15. Changes in time-use and drug use by young adults in poor neighbourhoods of Greater Buenos Aires, Argentina, after the political transitions of 2001-2002: Results of a survey

    PubMed Central

    2011-01-01

    Background In some countries, "Big Events" like crises and transitions have been followed by large increases in drug use, drug injection and HIV/AIDS. Argentina experienced an economic crisis and political transition in 2001/2002 that affected how people use their time. This paper studies how time use changes between years 2001 and 2004, subsequent to these events, were associated with drug consumption in poor neighbourhoods of Greater Buenos Aires. Methods In 2003-2004, 68 current injecting drug users (IDUs) and 235 young non-IDUs, aged 21-35, who lived in impoverished drug-impacted neighbourhoods in Greater Buenos Aires, were asked about time use then and in 2001. Data on weekly hours spent working or looking for work, doing housework/childcare, consuming drugs, being with friends, and hanging out in the neighbourhood, were studied in relation to time spent using drugs. Field observations and focus groups were also conducted. Results After 2001, among both IDUs and non-IDUs, mean weekly time spent working declined significantly (especially among IDUs); time spent looking for work increased, and time spent with friends and hanging out in the neighbourhood decreased. We found no increase in injecting or non-injecting drug consumption after 2001. Subjects most affected by the way the crises led to decreased work time and/or to increased time looking for work--and by the associated increase in time spent in one's neighbourhood--were most likely to increase their time using drugs. Conclusions Time use methods are useful to study changes in drug use and their relationships to every day life activities. In these previously-drug-impacted neighbourhoods, the Argentinean crisis did not lead to an increase in drug use, which somewhat contradicts our initial expectations. Nevertheless, those for whom the crises led to decreased work time, increased time looking for work, and increased time spent in indoor or outdoor neighbourhood environments, were likely to spend more time

  16. Changes in time-use and drug use by young adults in poor neighbourhoods of Greater Buenos Aires, Argentina, after the political transitions of 2001-2002: Results of a survey.

    PubMed

    Rossi, Diana; Zunino Singh, Dhan; Pawlowicz, María Pía; Touzé, Graciela; Bolyard, Melissa; Mateu-Gelabert, Pedro; Sandoval, Milagros; Friedman, Samuel R

    2011-01-20

    In some countries, "Big Events" like crises and transitions have been followed by large increases in drug use, drug injection and HIV/AIDS. Argentina experienced an economic crisis and political transition in 2001/2002 that affected how people use their time. This paper studies how time use changes between years 2001 and 2004, subsequent to these events, were associated with drug consumption in poor neighbourhoods of Greater Buenos Aires. In 2003-2004, 68 current injecting drug users (IDUs) and 235 young non-IDUs, aged 21-35, who lived in impoverished drug-impacted neighbourhoods in Greater Buenos Aires, were asked about time use then and in 2001. Data on weekly hours spent working or looking for work, doing housework/childcare, consuming drugs, being with friends, and hanging out in the neighbourhood, were studied in relation to time spent using drugs. Field observations and focus groups were also conducted. After 2001, among both IDUs and non-IDUs, mean weekly time spent working declined significantly (especially among IDUs); time spent looking for work increased, and time spent with friends and hanging out in the neighbourhood decreased.We found no increase in injecting or non-injecting drug consumption after 2001. Subjects most affected by the way the crises led to decreased work time and/or to increased time looking for work--and by the associated increase in time spent in one's neighbourhood--were most likely to increase their time using drugs. Time use methods are useful to study changes in drug use and their relationships to every day life activities. In these previously-drug-impacted neighbourhoods, the Argentinean crisis did not lead to an increase in drug use, which somewhat contradicts our initial expectations. Nevertheless, those for whom the crises led to decreased work time, increased time looking for work, and increased time spent in indoor or outdoor neighbourhood environments, were likely to spend more time using drugs. These data suggest that

  17. Drivers of pCO2 dynamics in two contrasting coral reef lagoons: The influence of submarine groundwater discharge (Invited)

    NASA Astrophysics Data System (ADS)

    Cyronak, T.; Santos, I. R.; Erler, D.; Maher, D. T.; Eyre, B.

    2013-12-01

    The carbon chemistry of coral reef lagoons can be highly variable over short time scales. While much of the diel variability in seawater carbon chemistry is explained by biological processes, external sources such as river and groundwater seepage may deliver large amounts of organic and inorganic carbon to coral reefs and represent a poorly understood feedback to ocean acidification. Here, we assess the impact of submarine groundwater discharge (SGD) on pCO2 variability in two coral reef lagoons with distinct SGD driving mechanisms. Diel variability of pCO2 in the two ecosystems was explained by a combination of biological drivers and SGD inputs. In Rarotonga, a South Pacific volcanic island, SGD was driven primarily by a steep terrestrial hydraulic gradient, and the lagoon was influenced by the high pCO2 (5,501 μatm) of the fresh groundwater. In Heron Island, a Great Barrier Reef coral cay, SGD was dominated by seawater recirculation through sediments (i.e. tidal pumping) and pCO2 was mainly impacted through the stimulation of biological processes. The Rarotonga water column had a relatively higher average pCO2 (549 μatm) than Heron Island (471 μatm). However, pCO2 exhibited a greater diel range in Heron Island (778 μatm) than in Rarotonga (507 μatm). The Rarotonga lagoon received 31.2 mmol CO2 m-2 d-1 from SGD, while the Heron Island lagoon received 12.3 mmol CO2 m-2 d-1. Over the course of this study both systems were sources of CO2 to the atmosphere (3.00 to 9.67 mmol CO2 m-2 d-1), with SGD-derived CO2 contributing a large portion to the air-sea CO2 flux. The relationship between both water column pH and aragonite saturation state (ΩAr) and radon (222Rn) concentrations indicate that SGD may enhance the local acidification of some coral reef lagoons. Studies measuring the carbon chemistry of coral reefs (e.g. community metabolism, calcification rates) may need to consider SGD-derived CO2.

  18. Radiological and hyperfine characterization of soils from the Northeastern region of the Province of Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Montes, M. L.; Mercader, R. C.; Taylor, M. A.; Runco, J.; Imbellone, P.; Rivas, P. C.; Desimoni, J.

    2011-11-01

    The activity concentrations of both natural (238U and 232Th chains and 40K) and anthropogenic (137Cs) radionuclides down along the soil profile have been determined in soil samples collected from inland and coastal areas of the La Plata River, located in the Northeastern region of the Province of Buenos Aires, Argentina. These studies were complemented with 57Fe Mössbauer spectroscopy characterization, pH, texture and organic carbon content measurements. From Mössbauer results, the sample compositions differ from one area to the other. Spectra from both soil samples are dominated by the Fe3+ paramagnetic signal. For soil samples from the coastal area, the α-Fe2O3 contribution is lower, Fe3O4 was not detected, and the relative areas of each spectral contribution are nearly constant with depth. For samples from the inland area, the Fe3+ paramagnetic fraction increases up to 82%, mainly at the expense of the magnetically ordered phase. The main observed activity originates from the decay of 40K (540-750 Bq/kg), followed by 238U (60-92 Bq/kg) and 232Th (37-46 Bq/kg) chains. The activity of 235U was in all the cases lower than the detection limit (LD = 0.02 Bq/kg). The only determined anthropogenic nuclide was 137Cs, arising from the fallout of the Southern Hemisphere nuclear weapon tests. Three of the observed differences in the depth distributions can be described by the dispersion-convection model. A correlation between the natural nuclide activities and the Mössbauer relative fractions was found, whereas no correlation was found between the 137Cs profile and the relative fraction of Fe3O4 or with other iron species.

  19. [Yeast urinary tract infections. Multicentre study in 14 hospitals belonging to the Buenos Aires City Mycology Network].

    PubMed

    Maldonado, Ivana; Arechavala, Alicia; Guelfand, Liliana; Relloso, Silvia; Garbasz, Claudia

    2016-01-01

    Urinary tract infections are a frequent ailment in patients in intensive care units. Candida and other yeasts cause 5-12% of these infections. The value of the finding of any yeast is controversial, and there is no consensus about which parameters are adequate for differentiating urinary infections from colonization or contamination. To analyse the epidemiological characteristics of patients with funguria, to determine potential cut-off points in cultures (to distinguish an infection from other conditions), to identify the prevalent yeast species, and to determine the value of a second urine sample. A multicentre study was conducted in intensive care units of 14 hospitals in the Buenos Aires City Mycology Network. The first and second samples of urine from every patient were cultured. The presence of white cells and yeasts in direct examination, colony counts, and the identification of the isolated species, were evaluated. Yeasts grew in 12.2% of the samples. There was no statistical correlation between the number of white cells and the fungal colony-forming units. Eighty five percent of the patients had indwelling catheters. Funguria was not prevalent in women or in patients over the age of 65. Candida albicans, followed by Candida tropicalis, were the most frequently isolated yeasts. Candida parapsilosis and Candida glabrata appeared less frequently. The same species were isolated in 70% of second samples, and in 23% of the cases the second culture was negative. It was not possible to determine a useful cut-off point for colony counts to help in the diagnosis of urinary infections. As in other publications, C. albicans, followed by C. tropicalis, were the most prevalent species. Copyright © 2015 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

  20. Trace metals in sediments of two estuarine lagoons from Puerto Rico.

    PubMed

    Acevedo-Figueroa, D; Jiménez, B D; Rodríguez-Sierra, C J

    2006-05-01

    Concentrations of As, Cd, Cu, Fe, Hg, Pb and Zn were evaluated in surface sediments of two estuaries from Puerto Rico, known as San José Lagoon (SJL) and Joyuda Lagoon. Significantly higher concentrations in microg/g dw of Cd (1.8 vs. 0.1), Cu (105 vs. 22), Hg (1.9 vs. 0.17), Pb (219 vs. 8), and Zn (531 vs. 52) were found in sediment samples from SJL when compared to Joyuda Lagoon. Average concentrations of Hg, Pb, and Zn in some sediment samples from SJL were above the effect range median (ERM) that predict toxic effects to aquatic organisms. Enrichments factors using Fe as a normalizer, and correlation matrices showed that metal pollution in SJL was the product of anthropogenic sources, while the metal content in Joyuda Lagoon was of natural origins. Sediment metal concentrations found in SJL were comparable to aquatic systems classified as contaminated from other regions of the world.

  1. Reprint of "Survey and first molecular characterization of Echinococcus granulosus sensu stricto (G1) in Pampas fox (Lycalopex gymnocercus) in Buenos Aires province, Argentina".

    PubMed

    Scioscia, Nathalia Paula; Petrigh, Romina Sandra; Beldomenico, Pablo Martín; Fugassa, Martín; Denegri, Guillermo María

    2017-01-01

    Echinococcosis is a zoonosis caused by tapeworms of the genus Echinococcus. Echinococcus granulosus sensu lato (s. l.) has a world-wide distribution and its transmission is primarily maintained in a synanthropic cycle with dogs as definitive hosts and livestock species as intermediate hosts. However, many wild canids also function as definitive hosts for E. granulosus s. l. Echinococcosis in humans is mainly caused by E. granulosus sensu stricto (s. s.) G1 genotype. In the present work, we expanded the epidemiological study on echinococcosis reported cases in Pampas fox (Lycalopex gymnocercus) to provide a prevalence estimate for rural areas of southern Buenos Aires province, Argentina. Ninety-five whole intestines were analyzed using the sedimentation and counting technique with a result of 83 foxes (87.37%) harboring at least one helminth species. E. granulosus s. l. adults were found in one Pampas fox (1.05%). These adult helminthes were E. granulosus s. s. (G1) according to the genotyping analysis of a 450-bp region of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Wind erosion risk in the southwest of Buenos Aires Province, Argentina, and its relationship to the productivity index

    NASA Astrophysics Data System (ADS)

    Silenzi, Juan C.; Echeverría, Nora E.; Vallejos, Adrián G.; Bouza, Mariana E.; De Lucia, Martín P.

    2012-01-01

    Wind erosion risk (WER) for soils of each municipality in the southwest (SW) of Buenos Aires Province (10,491,172 ha) was determined using the wind erosion equation (WEQ) model. WER results from multiplying the soil erodibility index (" I") of the soil by the climatic factor ( C). WER (Mg ha -1 year -1) of each municipality was: Bahía Blanca: 22.4, Coronel Dorrego: 18.6, Coronel Pringles: 4.5, Coronel Rosales: 48.2, Coronel Suárez: 4.5, Guaminí: 3.0, Patagones: 104.6, Puan: 12.2, Saavedra: 3.0, Tornquist: 6.8, and Villarino: 31.7. The maximum weighted average of " I" (Mg ha -1 year -1) corresponded to Coronel Rosales (87.6), Patagones (87.2), Villarino (85.7), Puan (67.9); Guaminí (59.6), Coronel Dorrego (53.1), and Bahía Blanca (39.3); the remaining municipalities ranged between 34.9 and 32.1 Mg ha -1 year -1. The highest C (%) corresponded to Patagones (120), Bahía Blanca (57), Coronel Rosales (55), Villarino (37), Coronel Dorrego (35), Tornquist (21), and Puan (18); for the remaining municipalities it was 14%. The productivity index (PI) is known to establish a numerical value of the productive capacity of lands. The relationship between WER and PI, weighted averages, in all the studied municipalities was fitted by means of a linear model, WER (Mg ha -1 year -1) = 95.23 - 2.09 * PI (%) ( R2 = 66%), and a second-order polynomial model, WER (Mg ha -1 year -1) = 139.41 - 5.86 * PI (%) + 0.07 * PI 2 (%) ( R2 = 74%). No statistically significant relationship was found between WER and PI for each municipality.

  3. [The configuration of nursing labor conditions in the Buenos Aires Metropolitan Area: An analysis at the intersection of the gender order and the organization of the health system].

    PubMed

    Pereyra, Francisca; Micha, Ariela

    2016-01-01

    The article explores two key factors which contribute to shape the poor working conditions of nursing in Argentina. A first objective focuses on exploring the effect of the occupation's care component, closely associated with cultural images of "inherent" female qualities, on working conditions. A second objective aims to examine the way in which the organization of health services provision in Argentina intensifies the vulnerability of this occupation. Regarding the methodology, the fieldwork conducted in the Metropolitan Area of Buenos Aires included in-depth interviews with key informants and group interviews with nurses. Among the results, on the one hand it is shown how the social devaluation of care is reflected in the discourse of those who perform the occupation as well as in institutional practices and policies in the health sector. On the other hand, it is shown that the decentralization and fragmentation of the health system act as additional obstacles hampering the articulation of labor demands.

  4. Project summary. PERSISTENCE OF PATHOGENS IN LAGOON-STORED SLUDGE (EPA/600/S2-89/015)

    EPA Science Inventory

    The project objective was to investigate pathogen inactlvation in lagoon-stored municipal sludges. The in-field lagoons were located in Louisiana (New Orleans) and in Texas (Port Aransas), both semitropical areas of the United States. Each lagoon was filled with 7.56 mL of ...

  5. Relationship between geohydrology and Upper Pleistocene-Holocene evolution of the eastern region of the Province of Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Capítulo, Leandro Rodrigues; Kruse, Eduardo E.

    2017-07-01

    The Upper Pleistocene-Holocene geological evolution, which is characterized by its landscape-forming energy and is related to geological and geomorphological complexity, has an impact on the groundwater dynamics of coastal aquifers. The geological configuration of a sector of the east coast of the Province of Buenos Aires was analyzed, as well as its connection with the geological and geomorphological history of the region during the Late Pleistocene and Holocene, and its influence on the regional and local geohydrological behaviour. This analysis was based on the application of the concept of hydrofacies. Boreholes were drilled and sampled (with depths of up to 40 m), and vertical electrical sounding, electrical tomography and pumping tests were undertaken. The description of the cutting samples by means of a stereo microscope, the interpretation of satellite images, and the construction of lithological and hydrogeological profiles and flow charts were carried out in the laboratory, and then integrated in a GIS. The identification of the lithological units and their distribution in the area allowed the construction of an evolutionary geological model for the Late Pleistocene and Holocene. Three aquifer units can be recognized: one of Late Pleistocene age (hydrofacies E) and the other two of Holocene age (hydrofacies A and C); their hydraulic connection depends on the occurrence and thickness variation of the aquitard units (hydrofacies B and D). The approach adopted allows the examination of the possibilities for groundwater exploitation and constitutes an applied conceptual framework to be taken into consideration when developing conceptual and numerical models at the local and regional scales.

  6. Redescription of Austrodiplostomum compactum (Trematoda: Diplostomidae) from its Type Host and Locality in Venezuela, and of Austrodiplostomum mordax from Argentina.

    PubMed

    de Núñez, Margarita Ostrowski

    2017-10-01

    Austrodiplostomum compactum from Nannopterum brasilianus, and its metacercaria from Geophagus sp. and Oreochromis mossambicus captured (1979) at its type locality, Valencia Lake, Venezuela, by the author, are redescribed. The adult is characterized by its large body size, and an oral sucker smaller than the pharynx. The metacercaria has a similar body size as the adult, and the small genital primordia occupy 4.1-7.3% of body length. Experimental infections in chickens with metacercariae of Diplostomulum mordax from brains of Odonthestes bonariensis, captured (2015) at Dique Paso de las Piedras, near Bahia Blanca City, Buenos Aires Province, Argentina, resulted in 10 adults 5 days postexposure. These adults correspond to Austrodiplostomum mordax as described from N. brasilianus at Lacombe Lagoon, Buenos Aires Province, and differ from A. compactum in their smaller body size, and an oral sucker larger than the pharynx. The metacercaria has a similar body size as the adult and differs mainly in that the larger genital primordia occupy 11.6-13.8% of body length. The status of earlier published Austrodiplostomum species in the American continent is discussed in view of available morphological and molecular data. A lectotype of A. mordax is here designated, and Austrodiplostomum ostrowskiae is considered as a new synonym of A. compactum.

  7. Bacterioplankton diversity and community composition in the Southern Lagoon of Venice.

    PubMed

    Simonato, Francesca; Gómez-Pereira, Paola R; Fuchs, Bernhard M; Amann, Rudolf

    2010-04-01

    The Lagoon of Venice is a large water basin that exchanges water with the Northern Adriatic Sea through three large inlets. In this study, the 16S rRNA approach was used to investigate the bacterial diversity and community composition within the southern basin of the Lagoon of Venice and at one inlet in October 2007 and June 2008. Comparative sequence analysis of 645 mostly partial 16S rRNA gene sequences indicated high diversity and dominance of Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes at the lagoon as well as at the inlet station, therefore pointing to significant mixing. Many of these sequences were close to the 16S rRNA of marine, often coastal, bacterioplankton, such as the Roseobacter clade, the family Vibrionaceae, and class Flavobacteria. Sequences of Actinobacteria were indicators of a freshwater input. The composition of the bacterioplankton was quantified by catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) with a set of rRNA-targeted oligonucleotide probes. CARD-FISH counts corroborated the dominance of members of the phyla Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes. When assessed by a probe set for the quantification of selected clades within Alphaproteobacteria and Gammaproteobacteria, bacterioplankton composition differed between October 2007 and June 2008, and also between the inlet and the lagoon. In particular, members of the readily culturable copiotrophic gammaproteobacterial genera Vibrio, Alteromonas and Pseudoalteromonas were enriched in the southern basin of the Lagoon of Venice. Interestingly, the alphaproteobacterial SAR11 clade and related clusters were also present in high abundances at the inlet and within the lagoon, which was indicative of inflow of water from the open sea.

  8. Chasing boundaries and cascade effects in a coupled barrier - marshes - lagoon system

    NASA Astrophysics Data System (ADS)

    Lorenzo Trueba, J.; Mariotti, G.

    2015-12-01

    Low-lying coasts are often characterized by barriers islands, shore-parallel stretches of sand separated from the mainland by marshes and lagoons. We built an exploratory numerical model to examine the morphological feedbacks within an idealized barrier - marshes -lagoon system and predict its evolution under projected rates of sea level rise and sediment supply to the backbarrier environment. Our starting point is a recently developed morphodynamic model, which couples shoreface evolution and overwash processes in a dynamic framework. As such, the model is able to capture dynamics not reproduced by morphokinematic models, which advect geometries without specific concern to processes. These dynamics include periodic barrier retreat due to time lags in the shoreface response to barrier overwash, height drowning due to insufficient overwash fluxes as sea level rises, and width drowning, which occurs when the shoreface response rate is insufficient to maintain the barrier geometry during overwash-driven landward migration. We extended the model by coupling the barrier model with a model for the evolution of the marsh platform and the boundary between the marsh and the adjacent lagoon. The coupled model explicitly describes marsh edge processes and accounts for the modification of the wave regime associated with lagoon width (fetch). Model results demonstrate that changes in factors that are not typically associated with the dynamics of coastal barriers, such as the lagoon width and the rate of export/import of sediments from and to the lagoon, can lead to previously unidentified complex responses of the coupled system. In particular, a wider lagoon in the backbarrier, and/or a reduction in the supply of muddy sediments to the backbarrier, can increase barrier retreat rates and even trigger barrier drowning. Overall, our findings highlight the importance of incorporating backbarrier dynamics in models that aim at predicting the response of barrier systems.

  9. Impact of mussel bioengineering on fine-grained sediment dynamics in a coastal lagoon: A numerical modelling investigation

    NASA Astrophysics Data System (ADS)

    Forsberg, Pernille L.; Lumborg, Ulrik; Bundgaard, Klavs; Ernstsen, Verner B.

    2017-12-01

    Rødsand lagoon in southeast Denmark is a non-tidal coastal lagoon. It is home to a wide range of marine flora and fauna and part of the Natura 2000 network. An increase in turbidity through elevated levels of suspended sediment concentration (SSC) within the lagoon may affect the ecosystem health due to reduced light penetration. Increasing SSC levels within Rødsand lagoon could be caused by increasing storm intensity or by a sediment spill from dredging activities west of the lagoon in relation to the planned construction of the Fehmarnbelt fixed link between Denmark and Germany. The aim of the study was to investigate the impact of a mussel reef on sediment import and SSC in a semi-enclosed lagoon through the development of a bioengineering modelling application that makes it possible to include the filtrating effect of mussels in a numerical model of the lagoonal system. The numerical implementation of an exterior mussel reef generated a reduction in the SSC in the vicinity of the reef, through the adjacent inlet and in the western part of the lagoon. The mussel reef reduced the sediment import to Rødsand lagoon by 13-22% and reduced the SSC within Rødsand lagoon by 5-9% depending on the filtration rate and the reef length. The results suggest that the implementation of a mussel reef has the potential to relieve the pressure of increasing turbidity levels within a semi-enclosed lagoonal system. However, further assessment and development of the bioengineering application and resulting ecosystem impacts are necessary prior to actual implementation.

  10. Analysis of the unique geothermal microbial ecosystem of the Blue Lagoon.

    PubMed

    Petursdottir, Solveig K; Bjornsdottir, Snaedis H; Hreggvidsson, Gudmundur O; Hjorleifsdottir, Sigridur; Kristjansson, Jakob K

    2009-12-01

    Cultivation and culture-independent techniques were used to describe the geothermal ecosystem of the Blue Lagoon in Iceland. The lagoon contains both seawater and freshwater of geothermal origin and is extremely high in silica content. Water samples were collected repeatedly in summer and autumn in 2003 and 2005 and in winter 2006 were analyzed for species composition. The study revealed the typical traits of an extreme ecosystem characterized by dominating species and other species represented in low numbers. A total of 35 taxa were identified. The calculated biodiversity index of the samples was 2.1-2.5. The majority (83%) of analyzed taxa were closely related to bacteria of marine and geothermal origin reflecting a marine character of the ecosystem and the origin of the Blue Lagoon hydrothermal fluid. A high ratio (63%) of analyzed taxa represented putative novel bacterial species. The majority (71%) of analyzed clones were Alphaproteobacteria, of which 80% belonged to the Roseobacter lineage within the family of Rhodobacteraceae. Of seven cultivated species, the two most abundant ones belonged to this lineage. Silicibacter lacuscaerulensis was confirmed as a dominating species in the Blue Lagoon. One group of isolates represented a recently identified species within the genus of Nitratireductor within Rhizobiales. This study implies an annually stable and seasonally dynamic ecosystem in the Blue Lagoon.

  11. Changes in sludge accumulation of anaerobic swine lagoons receiving pretreated influent

    USDA-ARS?s Scientific Manuscript database

    This study evaluated the changes in sludge depth and volume of anaerobic swine lagoon in North Carolina after six years of applying treatment to the liquid flushed manure prior to entering the lagoon. The farm had seven swine barns with a permitted capacity of 5,145 head feeder to finish (735 head/b...

  12. U-Th and 10Be constraints on sediment recycling in proglacial settings, Lago Buenos Aires, Patagonia

    NASA Astrophysics Data System (ADS)

    Cogez, Antoine; Herman, Frédéric; Pelt, Éric; Reuschlé, Thierry; Morvan, Gilles; Darvill, Christopher M.; Norton, Kevin P.; Christl, Marcus; Märki, Lena; Chabaux, François

    2018-03-01

    The estimation of sediment transfer times remains a challenge to our understanding of sediment budgets and the relationships between erosion and climate. Uranium (U) and thorium (Th) isotope disequilibria offer a means of more robustly constraining sediment transfer times. Here, we present new uranium and thorium disequilibrium data for a series of nested moraines around Lago Buenos Aires in Argentine Patagonia. The glacial chronology for the area is constrained using in situ cosmogenic 10Be analysis of glacial outwash. Sediment transfer times within the periglacial domain were estimated by comparing the deposition ages of moraines to the theoretical age of sediment production, i.e., the comminution age inferred from U disequilibrium data and recoil loss factor estimates. Our data show first that the classical comminution age approach must include weathering processes accounted for by measuring Th disequilibrium. Second, our combined data suggest that the pre-deposition history of the moraine sediments is not negligible, as evidenced by the large disequilibrium of the youngest moraines despite the equilibrium of the corresponding glacial flour. Monte Carlo simulations suggest that weathering was more intense before the deposition of the moraines and that the transfer time of the fine sediments to the moraines was on the order of 100-200 kyr. Long transfer times could result from a combination of long sediment residence times in the proglacial lake (recurrence time of a glacial cycle) and the remobilization of sediments from moraines deposited during previous glacial cycles. 10Be data suggest that some glacial cycles are absent from the preserved moraine record (seemingly every second cycle), supporting a model of reworking moraines and/or fluctuations in the extent of glacial advances. The chronological pattern is consistent with the U-Th disequilibrium data and the 100-200 kyr transfer time. This long transfer time raises the question of the proportion of freshly

  13. Whiteriver Sewage Lagoons, Whiteriver, AZ: AZ0024058

    EPA Pesticide Factsheets

    Authorization to Discharge Under National Pollutant Discharge Elimination System (NPDES) Permit No. AZ0024058 for Tribal Utility Authority, White Mountain Apache Tribe Whiteriver Sewage Lagoons, Whiteriver, AZ.

  14. Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?

    NASA Astrophysics Data System (ADS)

    Van Wynsberge, Simon; Menkes, Christophe; Le Gendre, Romain; Passfield, Teuru; Andréfouët, Serge

    2017-12-01

    In remote coral reef environments, lagoon and reef in situ measurements of temperature are scarce. Sea Surface Temperature (SST) measured by satellite has been frequently used as a proxy of the lagoon temperature experienced by coral reef organisms (TL) especially during coral bleaching events. However, the link between SST and TL is poorly characterized. First, we compared the correlation between various SST series and TL from 2012 to 2016 in three atolls and one island in the Central South Pacific Ocean. Simple linear correlation between SST and TL ranged between 0.44 and 0.97 depending on lagoons, localities of sensors, and type of SST data. High-resolution-satellite-measurements of SST inside the lagoons did not outperform oceanic SST series, suggesting that SST products are not adapted for small lagoons. Second, we modelled the difference between oceanic SST and TL as a function of the drivers of lagoon water renewal and mixing, namely waves, tide, wind, and season. The multivariate models reduced significantly the bias between oceanic SST and TL. In atoll lagoons, and probably in other hydrodynamically semi-open systems, a correction taking into account these factors is necessary when SST are used to characterize organisms' thermal stress thresholds.

  15. [Species and size composition of fishes in Barra de Navidad lagoon, Mexican central Pacific].

    PubMed

    González-Sansón, Gaspar; Aguilar-Betancourt, Consuelo; Kosonoy-Aceves, Daniel; Lucano-Ramírez, Gabriela; Ruiz-Ramírez, Salvador; Flores-Ortega, Juan Ramón; Hinojosa-Larios, Angel; de Asís Silva-Bátiz, Francisco

    2014-03-01

    Coastal lagoons are considered important nursery areas for many coastal fishes. Barra de Navidad coastal lagoon (3.76km2) is important for local economy as it supports tourism development and artisanal fisheries. However, the role of this lagoon in the dynamics of coastal fish populations is scarcely known. Thus, the objectives of this research were: to characterize the water of the lagoon and related weather conditions, to develop a systematic list of the ichthyofauna, and to estimate the proportion of juveniles in the total number of individuals captured of most abundant species. Water and fish samples were collected between March 2011 and February 2012. Physical and chemical variables were measured in rainy and dry seasons. Several fishing gears were used including a cast net, beach purse seine and gillnets of four different mesh sizes. Our results showed that the lagoon is most of the time euhaline (salinity 30-40ups), although it can be mixopolyhaline (salinity 18-30ups) during short periods. Chlorophyll and nutrients concentrations suggested eutrophication in the lagoon. Mean water temperature changed seasonally from 24.9 degrees C (April, high tide) to 31.4 degrees C (October, low tide). Considering ichthyofauna species, a total of 36 448 individuals of 92 species were collected, 31 of them adding up to 95% of the total of individuals caught. Dominant species were Anchoa spp. (44.6%), Diapterus peruvianus (10.5%), Eucinostomus currani (8.1%), Cetengraulis mysticetus (7.8%), Mugil curema (5.2%) and Opisthonema libertate (4.5%). The lagoon is an important juvenile habitat for 22 of the 31 most abundant species. These included several species of commercial importance such as snappers (Lutjanus argentiventris, L. colorado and L. novemfasciatus), snook (Centropomus nigrescens) and white mullet (Mugil curema). Other four species seem to use the lagoon mainly as adults. This paper is the first contribution on the composition of estuarine ichthyofauna in Jalisco

  16. Spatial variability in fish species assemblage and community structure in four subtropical lagoons of the Okavango Delta, Botswana

    NASA Astrophysics Data System (ADS)

    Mosepele, K.; Mosepele, B.; Bokhutlo, T.; Amutenya, K.

    The species assemblage and community structure of four lagoons was assessed through time series data collected between 2001 and 2005 in the Okavango Delta. The main aim of this study was to evaluate the importance of lagoons as fish habitats in the Delta. Therefore, this study assessed the importance of these habitats through determining fish species diversity, composition, relative abundance, and community structure between the lagoons. Forty six species belonging to 11 families and five orders were collected over the study period. Main results showed that Cichlidae was the most important family and had the highest species richness in the lagoons. Significant differences ( p < 0.05) were observed in species richness, faunal composition, and diversity among some of the lagoons. Moreover, there were also variations in species composition, and also significant differences in mean length and weight of some selected fish species in the four lagoons. This study showed that lagoons are important repositories of food fish to local communities. Moreover, a management of the fish stocks based on restricting fishing in some lagoons as protected areas is not feasible because of these significant differences in species assemblages between lagoons. Furthermore, lagoons are subject to multiple where most of the lodges are constructed, which makes subsequently makes them vulnerable to pollution. Therefore, the integrity of lagoon habitats needs to be maintained so that their ecosystem functioning (i.e. fish repositories) is maintained.

  17. Monitoring benthic foraminiferal dynamics at Bottsand coastal lagoon (western Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Schönfeld, Joachim

    2018-04-01

    Benthic foraminifera from Bottsand coastal lagoon, western Baltic Sea, have been studied since the mid-1960s. They were monitored annually in late autumn since 2003 at the terminal ditch of the lagoon. There were 12 different species recognised, of which three have not been recorded during earlier investigations. Dominant species showed strong interannual fluctuations and a steady increase in population densities over the last decade. Elphidium incertum, a stenohaline species of the Baltic deep water fauna, colonised the Bottsand lagoon in 2016, most likely during a period of salinities >19 units and water temperatures of 18 °C on average in early autumn. The high salinities probably triggered their germination from a propagule bank in the ditch bottom sediment. The new E. incertum population showed densities higher by an order of magnitude than those of the indigenous species. The latter did not decline, revealing that E. incertum used another food source or occupied a different microhabitat. Elphidium incertum survived transient periods of lower salinities in late autumn 2017, though with reduced abundances, and became a regular faunal constituent at the Bottsand lagoon.

  18. Methane fluxes from tropical coastal lagoons surrounded bymangroves, Yucatán, Mexico

    USGS Publications Warehouse

    Chuang, Pei-Chuan; Young, Megan B.; Dale, Andrew W.; Miller, Laurence G.; Herrera-Silveira, Jorge A; Paytan, Adina

    2017-01-01

    Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m−2 d−1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.

  19. Chasing boundaries and cascade effects in a coupled barrier-marsh-lagoon system

    NASA Astrophysics Data System (ADS)

    Lorenzo-Trueba, Jorge; Mariotti, Giulio

    2017-08-01

    The long-term dynamic evolution of an idealized barrier-marsh-lagoon system experiencing sea-level rise is studied by coupling two existing numerical models. The barrier model accounts for the interaction between shoreface dynamics and overwash flux, which allows the occurrence of barrier drowning. The marsh-lagoon model includes both a backbarrier marsh and an interior marsh, and accounts for the modification of the wave regime associated with changes in lagoon width and depth. Overwash, the key process that connects the barrier shoreface with the marsh-lagoon ecosystems, is formulated to account for the role of the backbarrier marsh. Model results show that a number of factors that are not typically associated with the dynamics of coastal barriers can enhance the rate of overwash-driven landward migration by increasing backbarrier accommodation space. For instance, lagoon deepening could be triggered by marsh edge retreat and consequent export of fine sediment via tidal dispersion, as well as by an expansion of inland marshes and consequent increase in accommodation space to be filled in with sediment. A deeper lagoon results in a larger fraction of sediment overwash being subaqueous, which coupled with a slow shoreface response sending sediment onshore can trigger barrier drowning. We therefore conclude that the supply of fine sediments to the back-barrier and the dynamics of both the interior and backbarrier marsh can be essential for maintaining the barrier system under elevated rates of sea-level rise. Our results highlight the importance of considering barriers and their associated backbarriers as part of an integrated system in which sediment is exchanged.

  20. Assessment of the trophic state of a hypersaline-carbonatic environment: Vermelha Lagoon (Brazil)

    PubMed Central

    Martins, Maria Virginia Alves; Frontalini, Fabrizio; Ballalai, João M.; Belart, Pierre; Habib, Renan; Fontana, Luiz F.; Clemente, Iara M. M. M.; Lorini, Maria Lucia; Mendonça Filho, João G.; Laut, Vanessa M.; Figueiredo, Marcos de Souza Lima

    2017-01-01

    Vermelha Lagoon is a hypersaline shallow transitional ecosystem in the state of Rio de Janeiro (Brazil). This lagoon is located in the protected area of Massambaba, between the cities of Araruama and Saquarema (Brazil), and displays two quite uncommon particularities: it exhibits carbonate sedimentation and displays the development of Holocene stromatolites. Due to both particularities, the salt industry and property speculation have been, increasingly, generating anthropic pressures on this ecosystem. This study aims to apply a multiproxy approach to evaluate the trophic state of Vermelha Lagoon based on physicochemical parameters and geochemical data for the quantification and qualification of organic matter (OM), namely total organic carbon (TOC), total sulfur (TS), total phosphorus (TP) and biopolymeric carbon (BPC), including carbohydrates (CHO), lipids (LIP) and proteins (PTN). The CHO/TOC ratio values suggest that OM supplied to the sediment is of autochthonous origin and results, essentially, from microbial activity. The cluster analyses allowed the identification of four regions in Vermelha Lagoon. The Region I included stations located in shallow areas of the eastern sector of Vermelha lagoon affected by the impact of the artificial channel of connection with Araruama Lagoon. The Region II, under the influence of salt pans, is characterized by the highest values of BPC, namely CHO promoted by microbiological activity. The Region III include stations spread through the lagoon with high values of dissolved oxygen and lower values of TP. Stromatolites and microbial mattes growth was observed in some stations of this sector. Region IV, where the highest values of TOC and TS were found, represents depocenters of organic matter, located in general in depressed areas. Results of this work evidences that the Vermelha Lagoon is an eutrophic but alkaline and well oxygenated environment (at both water column and surface sediment) where the autotrophic activity is

  1. Induction of Purple Sulfur Bacterial Growth in Dairy Wastewater Lagoons by Circulation

    USDA-ARS?s Scientific Manuscript database

    Aims: To determine if circulation of diary wastewater induces the growth of phototrophic purple sulfur bacteria (PSB). Methods and Results: Two dairy wastewater lagoons that were similar in size, geographic location, number and type of cattle loading the lagoons were chosen. The only obvious diffe...

  2. Assessing hog lagoon waste contamination in the Cape Fear Watershed using Bacteroidetes 16S rRNA gene pyrosequencing.

    PubMed

    Arfken, Ann M; Song, Bongkeun; Mallin, Michael A

    2015-09-01

    Hog lagoons can be major sources of waste and nutrient contamination to watersheds adjacent to pig farms. Fecal source tracking methods targeting Bacteroidetes 16S rRNA genes in pig fecal matter may underestimate or fail to detect hog lagoon contamination in riverine environments. In order to detect hog lagoon wastewater contamination in the Cape Fear Watershed, where a large number of hog farms are present, we conducted pyrosequencing analyses of Bacteroidetes 16S rRNA genes in hog lagoon waste and identified new hog lagoon-specific marker sequences. Additional pyrosequencing analyses of Bacteroidetes 16S rRNA genes were conducted with surface water samples collected at 4 sites during 5 months in the Cape Fear Watershed. Using an operational taxonomic unit (OTU) identity cutoff value of 97 %, these newly identified hog lagoon markers were found in 3 of the river samples, while only 1 sample contained the pig fecal marker. In the sample containing the pig fecal marker, there was a relatively high percentage (14.1 %) of the hog lagoon markers and a low pig fecal marker relative abundance of 0.4 % in the Bacteroidetes 16S rRNA gene sequences. This suggests that hog lagoon contamination must be somewhat significant in order for pig fecal markers to be detected, and low levels of hog lagoon contamination cannot be detected targeting only pig-specific fecal markers. Thus, new hog lagoon markers have a better detection capacity for lagoon waste contamination, and in conjunction with a pig fecal marker, provide a more comprehensive and accurate detection of hog lagoon waste contamination in susceptible watersheds.

  3. Assessing hydrological effects of human interventions on coastal systems: numerical applications to the Venice Lagoon

    NASA Astrophysics Data System (ADS)

    Ferrarin, C.; Ghezzo, M.; Umgiesser, G.; Tagliapietra, D.; Camatti, E.; Zaggia, L.; Sarretta, A.

    2013-05-01

    The hydrological consequences of historical, contemporary and future human activities on a coastal system were investigated by means of numerical models. The changes in the morphology of the Lagoon of Venice during the last century result from the sedimentological response to the combined effects of human interventions on the environment and global changes. This study focuses on changes from 1927 to 2012 and includes the changes planned for the protection of the city of Venice from storm surges and exceptional tides under future sea level rise scenarios. The application of a hydrodynamic model allowed for the analysis of the morphological effects on the lagoon circulation, the interaction with the sea and the internal mixing processes. The absolute values of the exchange between the lagoon and sea increased from 1927 to 2002 (from 3900 to 4600 m3 s-1), while the daily fraction of lagoon water volume exchanged decreased. At the same time, the flattening of the lagoon and loss of morphological heterogeneity enhanced the internal mixing processes driven by the tide and wind, reducing thus the overall water renewal time from 11.9 days in 1927 to 10.8 days in 2002. Morphological changes during the last decade reduced the water exchange through the inlets and induced an increase of the basin-wide water renewal time of 0.5 day. In the future, Venice Lagoon will evolve to a more restricted environment due to sea level rise, which increases the lagoon volume, and periodical closure of the lagoon from the sea during flooding events, which reduces the communication with the open sea. Therefore, the flushing capacity of the lagoon will decrease considerably, especially in its central part. Furthermore, some considerations on the impact of the hydromorphological changes on the ecological dynamics are proposed.

  4. Hubble reveals heart of Lagoon Nebula

    NASA Image and Video Library

    2010-09-22

    Image release date September 22, 2010 To view a video of this image go here: www.flickr.com/photos/gsfc/5014452203 Caption: A spectacular new NASA/ESA Hubble Space Telescope image reveals the heart of the Lagoon Nebula. Seen as a massive cloud of glowing dust and gas, bombarded by the energetic radiation of new stars, this placid name hides a dramatic reality. The Advanced Camera for Surveys (ACS) on the NASA/ESA Hubble Space Telescope has captured a dramatic view of gas and dust sculpted by intense radiation from hot young stars deep in the heart of the Lagoon Nebula (Messier 8). This spectacular object is named after the wide, lagoon-shaped dust lane that crosses the glowing gas of the nebula. This structure is prominent in wide-field images, but cannot be seen in this close-up. However the strange billowing shapes and sandy texture visible in this image make the Lagoon Nebula’s watery name eerily appropriate from this viewpoint too. Located four to five thousand light-years away, in the constellation of Sagittarius (the Archer), Messier 8 is a huge region of star birth that stretches across one hundred light-years. Clouds of hydrogen gas are slowly collapsing to form new stars, whose bright ultraviolet rays then light up the surrounding gas in a distinctive shade of red. The wispy tendrils and beach-like features of the nebula are not caused by the ebb and flow of tides, but rather by ultraviolet radiation’s ability to erode and disperse the gas and dust into the distinctive shapes that we see. In recent years astronomers probing the secrets of the Lagoon Nebula have found the first unambiguous proof that star formation by accretion of matter from the gas cloud is ongoing in this region. Young stars that are still surrounded by an accretion disc occasionally shoot out long tendrils of matter from their poles. Several examples of these jets, known as Herbig-Haro objects, have been found in this nebula in the last five years, providing strong support for

  5. Modelling alpha-diversities of coastal lagoon fish assemblages from the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Riera, R.; Tuset, V. M.; Betancur-R, R.; Lombarte, A.; Marcos, C.; Pérez-Ruzafa, A.

    2018-07-01

    Coastal lagoons are marine ecosystems spread worldwide with high ecological value; however, they are increasingly becoming deteriorated as a result of anthropogenic activity. Their conservation requires a better understanding of the biodiversity factors that may help identifying priority areas. The present study is focused on 37 Mediterranean coastal lagoons and we use predictive modelling approaches based on Generalized Linear Model (GLM) analysis to investigate variables (geomorphological, environmental, trophic or biogeographic) that may predict variations in alpha-diversity. It included taxonomic diversity, average taxonomic distinctness, and phylogenetic and functional diversity. Two GLM models by index were built depending on available variables for lagoons: in the model 1 all lagoons were used, and in the model 2 only 23. All alpha-diversity indices showed variability between lagoons associated to exogenous factors considered. The biogeographic region strongly conditioned most of models, being the first variable introduced in the models. The salinity and chlorophyll a concentration played a secondary role for the models 1 and 2, respectively. In general, the highest values of alpha-diversities were found in northwestern Mediterranean (Balearic Sea, Alborán Sea and Gulf of Lion), hence they might be considered "hotspots" at the Mediterranean scale and should have a special status for their protection.

  6. Pan-European management of coastal lagoons: A science-policy-stakeholder interface perspective

    NASA Astrophysics Data System (ADS)

    Lillebø, Ana I.; Stålnacke, Per; Gooch, Geoffrey D.; Krysanova, Valentina; Bielecka, Małgorzata

    2017-11-01

    The main objective of the work carried out in the scope of a three years collaborative research project was to develop science-based strategies and a decision support framework for the integrated management of coastal lagoons and their catchments and, in this context, to enhance connectivity between research and policymaking. In this paper our main objective is to share the lessons learned from the innovative methodology used throughout the project. To achieve the proposed objectives, the multidisciplinary scientific knowledge in the project team was combined and integrated with the knowledge and views of local stakeholders of four selected European coastal lagoons, using a three step participatory approach. With this innovative approach, which included the usage of eco-hydrological and water quality-modelling tools, the team developed and analyzed integrated scenarios of possible economic development and environmental impacts in four European lagoons and their catchments. These scenarios were presented and discussed with stakeholders, giving rise to management recommendations for each case study lagoon. Results show that some management options might be transferrable to other European lagoons having similar climatic, geophysical and socio-economic settings. In management terms, the project output provides a set of policy guidelines derived from the different analyses conducted and proposes initiatives concerning management implementation in a local-regional-national-European setting.

  7. Lagoon-sea exchanges, nutrient dynamics and water quality management of the Ria Formosa (Portugal)

    NASA Astrophysics Data System (ADS)

    Newton, Alice; Mudge, Stephen M.

    2005-02-01

    Historical data from the Ria Formosa lagoon are classified according to the EEA 2001 guidelines to provide a frame of reference to evaluate the effect of management during the implementation of the environmental legislative Directives. Water samples from the Ria Formosa lagoon were significantly enriched in nitrogen (NH 4+ NO 2- and NO 3-) with respect to the adjacent coastal waters indicating that inputs from sewage, agricultural runoff and benthic fluxes were not fully assimilated within the lagoon. Tidal flushing was insufficient in the inner areas of the lagoon to remove or effectively dilute these inputs. Enrichment was most severe close to the urban centres of Faro and Olhão, as well as in the Gilão Estuary and the shallow extremities. Dissolved oxygen undersaturation (mean 75% during daylight hours) was associated with the area close to the sewage outlets of Faro. In the shallow west end of the lagoon during summer, dissolved oxygen supersaturation reached 140% during the day but fell to 50% at night. Classification using the EEA (2001) guidelines suggests the system is "poor" or "bad" with respect to phosphate concentrations for the majority of the year and "poor" in nitrogen contamination during the autumn rainy period. Due to the high overall nitrogen load in the lagoon, there is a net export to the coastal waters, especially during November and December, and phosphate only becomes limiting briefly during the spring bloom (April). Therefore, substantial phytoplankton populations may be supported year-round in the lagoon. The consequences of water quality deterioration in the Ria Formosa would negatively affect the lagoon as a regional resource, important for its ecological, economic and recreational value. The industries most affected would be tourism, fisheries and aquaculture. Management options include Urban Waste Water Treatment, dredging, artificial inlets, limits on urban development and changes in agricultural practices.

  8. CISOCUR - Residence time modelling in the Curonian Lagoon and validation through stable isotope measurements

    NASA Astrophysics Data System (ADS)

    Umgiesser, Georg; Razinkovas-Baziukas, Arturas; Zemlys, Petras; Ertürk, Ali; Mėžinė, Jovita

    2015-04-01

    The spatial pattern of the hydrodynamic circulation of the Curonian lagoon, the largest European coastal lagoon, is still little understood. In absence of automatic current registration data all the existing models relied mostly on such data as water levels leaving high level of uncertainty. Here we present CISOCUR, a new project financed by European Social Fund under the Global Grant measure. The project applies a new methodology that uses the carbon stable isotope (SI) ratio of C12 and C13 that characterize different water sources entering the lagoon and may be altered by internal kinetic processes. Through the tracing of these isotope ratios different water masses can be identified. This gives the possibility to validate several hypotheses of water circulation and validate hydrodynamic models. In particular it will be possible to 1) trace water masses entering the lagoon through the Nemunas and the Klaipeda strait; 2) test the hypothesis of sediment transport mechanisms inside the lagoon; 3) evaluate the importance of physical forcing on the lagoon circulation. The use of a hydrodynamic finite element model, coupled with the SI method, will allow for a realistic description of the transport processes inside the Curonian lagoon. So the main research goal is to apply the stable isotope tracers and a finite element model to determine the circulation patterns in the Curonian lagoon. Here we show how the SI analysis was used to validate the hydrodynamic model on the basis of residence time. The average residence time of the Nemunas waters is estimated through SI data and is then compared with the model data computed through standard algorithms. Seasonal changes of carbon content are taken care of through a preliminary application of a carbon kinetic model. The results are compared to literature data.

  9. Spatial Variation in Development of Epibenthic Assemblages in a Coastal Lagoon

    NASA Astrophysics Data System (ADS)

    Benedetti-Cecchi, L.; Rindi, F.; Bertocci, I.; Bulleri, F.; Cinelli, F.

    2001-05-01

    Spatial and temporal patterns in colonization of epibenthic assemblages were measured in a coastal lagoon on the west coast of Italy using recruitment panels. It was proposed that if the ecological processes influencing development of assemblages were homogeneous within the lagoon, then there should be no differences in mean cover of colonists nor in spatial patterns of variance in abundance in different areas of the lagoon. In contrast, heterogeneity in ecological processes affecting development would be revealed by spatial variability in colonization. To test these hypotheses, two sticks each with five replicate panels were placed 3-5 m apart in each of two sites 30-100 m apart in each of three locations 500-100 m apart; the experiment was repeated three times between April and December 1999, using new sites at each location each time. The results revealed considerable spatial variation in the structure of developing assemblages across locations. There were significant Location or Time×Location effects in the mean abundance of common taxa, such as Enteromorpha intestinalis , Ulva rigida, Cladophora spp., bryozoans and serpulids. Patterns in spatial variation differed among locations for these organisms. Collectively, the results supported a model of spatial heterogeneity in intensity of processes influencing patterns of recruitment and development of epibenthic assemblages in the Lagoon of Orbetello. The implications of these results for management of environmental problems in complex, variable habitats such as coastal lagoons, are discussed.

  10. Phosphorus recovery from anaerobic swine lagoon sludge using the quick wash process

    USDA-ARS?s Scientific Manuscript database

    Long term accumulation of sludge in anaerobic swine lagoons reduces its storage volume and ability to treat waste. Usually, excess accumulation of lagoon sludge is removed using pumping dredges. The dredged sludge is then land applied at agronomic rates according to its nutrient content. The accumul...

  11. Phosphorus recovery from anaerobic swine lagoon sludge using the quick wash process

    USDA-ARS?s Scientific Manuscript database

    Long term and significant accumulation of sludge in anaerobic swine lagoons reduces its storage volume and ability to treat waste. Usually, excess accumulation of lagoon sludge is removed by dredging. The dredged sludge is then land applied at agronomic rates according to its nutrient content. Becau...

  12. Brominated Flame Retardants in Sediments of Four Coastal Lagoons of Yucatan, Mexico.

    PubMed

    Valenzuela-Sánchez, I S; Gold-Bouchot, G; Hernández-Núñez, E; Barrientos-Medina, R C; Garza-Gisholt, E; Zapata-Pérez, O

    2018-05-02

    We examined the sediments of four coastal lagoons (Ria Lagartos, Bocas de Dzilam, Laguna de Chelem and Ria Celestun) from the state of Yucatan, Mexico, for three widely used commercial polybrominated diphenyl ethers formulations (penta-, octa- and deca-BDE). The most commonly found congeners in all four lagoons were BDEs 47, 99 and 100 (all in the penta-BDE formulation) and BDE209 (deca-BDE formulation). The greatest variety and highest concentrations of brominated flame retardants were found in Ria Lagartos, which also showed the highest BDE 100 concentration (24.129 ng/g). Hexabromocyclododecane was found in all lagoons, but at lower concentrations than those of the various polybrominated diphenyl ethers. Dispersal routes of these compounds are discussed, such as a ring of sinkholes (cenotes) adjacent to the lagoons. Moreover, electronic waste is a serious problem because municipal landfills have been the primary disposal method for these wastes and therefore represent a reservoir of brominated fire retardants.

  13. Accuracy of vertical radial plume mapping technique in measuring lagoon gas emissions.

    PubMed

    Viguria, Maialen; Ro, Kyoung S; Stone, Kenneth C; Johnson, Melvin H

    2015-04-01

    Recently, the U.S. Environmental Protection Agency (EPA) posted a ground-based optical remote sensing method on its Web site called Other Test Method (OTM) 10 for measuring fugitive gas emission flux from area sources such as closed landfills. The OTM 10 utilizes the vertical radial plume mapping (VRPM) technique to calculate fugitive gas emission mass rates based on measured wind speed profiles and path-integrated gas concentrations (PICs). This study evaluates the accuracy of the VRPM technique in measuring gas emission from animal waste treatment lagoons. A field trial was designed to evaluate the accuracy of the VRPM technique. Control releases of methane (CH4) were made from a 45 m×45 m floating perforated pipe network located on an irrigation pond that resembled typical treatment lagoon environments. The accuracy of the VRPM technique was expressed by the ratio of the calculated emission rates (QVRPM) to actual emission rates (Q). Under an ideal condition of having mean wind directions mostly normal to a downwind vertical plane, the average VRPM accuracy was 0.77±0.32. However, when mean wind direction was mostly not normal to the downwind vertical plane, the emission plume was not adequately captured resulting in lower accuracies. The accuracies of these nonideal wind conditions could be significantly improved if we relaxed the VRPM wind direction criteria and combined the emission rates determined from two adjacent downwind vertical planes surrounding the lagoon. With this modification, the VRPM accuracy improved to 0.97±0.44, whereas the number of valid data sets also increased from 113 to 186. The need for developing accurate and feasible measuring techniques for fugitive gas emission from animal waste lagoons is vital for livestock gas inventories and implementation of mitigation strategies. This field lagoon gas emission study demonstrated that the EPA's vertical radial plume mapping (VRPM) technique can be used to accurately measure lagoon gas

  14. Nutrient budgets and trophic state in a hypersaline coastal lagoon: Lagoa de Araruama, Brazil

    NASA Astrophysics Data System (ADS)

    Souza, Marcelo F. L.; Kjerfve, Björn; Knoppers, Bastiaan; Landim de Souza, Weber F.; Damasceno, Raimundo N.

    2003-08-01

    Lagoa de Araruama in the state of Rio de Janeiro, Brazil, is a hypersaline lagoon with salinity varying spatially from 45 to 56. We collected water samples during monthly cruises throughout the lagoon, and along the streams feeding the system, from April 1991 to March 1992. Nutrients and other water quality parameters exhibited great spatial and temporal variations. Mass balance calculations indicate large amounts of anthropogenic nutrient inputs. The data indicate that the lagoon currently is oligotrophic but is in a state of transition to become a mesotrophic system. Molar dissolved inorganic nitrogen:dissolved inorganic phosphorus (DIN/DIP) varied between 2.2:1 and 659:1 with a volume-weighted average of 22:1. The high DIN/DIP ratio contrasts with that found in nearby lagoons, suggesting that phytoplankton primary production is limited by phosphorus in Lagoa de Araruama. The major loss of DIP is apparently driven by biological assimilation and diagenic reactions in the sediments. Calculations indicate that the lagoon is slightly net autotrophic at +0.9 mol C m -2 yr -1. This suggests that the biomass of the primary producers is restricted by phosphorus availability. Phosphorus retention in the sediment and the hypersaline state of the lagoon prevent changes in autotrophic communities and the formation of eutrophic conditions.

  15. Spatial distribution, enrichment, and source of environmentally important elements in Batticaloa lagoon, Sri Lanka.

    PubMed

    Adikaram, Madurya; Pitawala, Amarasooriya; Ishiga, Hiroaki; Jayawardana, Daham

    2017-01-01

    The present paper is the first documentation of distribution and contamination status of environmentally important elements of superficial sediments in the Batticaloa lagoon that is connected to the largest bay of the world. Surface sediment samples were collected from 34 sites covering all over the lagoon. Concentrations of elements such as As, Cr, Cu, Fe, Nb, Ni, Pb, Sc, Sr, Th, V, Y, Zn, and Zr were measured by X-ray florescence analysis. Geochemically, the lagoon has three different zones that were influenced mainly by fresh water sources, marine fronts, and intermediate mixing zones. The marine sediment quality standards indicate that Zr and Th values are exceeded throughout the lagoon. According to the freshwater sediment quality standards, Cr levels of all sampling sites exceed the threshold effect level (TEL) and 17 % of them are even above the probable effect level (PEL). Most sampling sites of the channel discharging areas show minor enrichment of Cu, Ni, and Zn with respect to the TEL. Contamination indices show that the lagoon mouth area is enriched with As. Statistical analysis implies that discharges from agricultural channel and marine fluxes of the lagoon effects on the spatial distribution of measured elements. Further research is required to understand the rate of contamination in the studied marine system.

  16. Phytoplankton chlorophyte structure as related to ENSO events in a saline lowland river (Salado River, Buenos Aires, Argentina)

    PubMed Central

    Solari, Lía C; Gabellone, Néstor A; Claps, María C; Casco, María A; Quaíni, Karina P; Neschuk, Nancy C

    2014-01-01

    We analyzed the phytoplankton present in the lower sector of the Salado River (Buenos Aires, Argentina) for 10 years (1995–2005) and detected significant changes occurring in chlorophyte abundance and species richness during La Niña event (1998–1999), which period was analyzed throughout the entire basin (main stream and tributaries). We compared the physicochemical and biologic variables between two El Niño–La Niña–Southern Oscillation (ENSO) periods – El Niño (March 1997–January 1998) and La Niña (May 1998–May 1999) – to identify possible indicators of a relationship between climatic anomalies and chlorophyte performance. Chlorophyte density increased during the La Niña. Under normal or extreme hydrologic conditions, mobile (Chlamydomonas spp.) and nonmobile (Monoraphidium spp.) chlorophytes codominated. These species belonged to Reynolds's functional groups X1 and X2, those typical of nutrient-enriched environments. Comparative analyses between El Niño and La Niña periods indicated significant differences in physicochemical (K+, dissolved polyphenols, particulate reactive phosphorus, alkalinity, pH) and biologic (species diversity and richness, phytoplankton and chlorophyte total densities) variables between the two periods at all basin sites. During the La Niña condition, species richness was greater owing to interconnected shallow lakes and drainage-channel inputs, while the Shannon diversity index was lower because of the high abundance values of Monoraphidium minutum. A detailed analysis of the chlorophytes in the entire basin, indicated that changes in density and species dominance occurred on a regional scale although diverse chlorophyte assemblages were identified in the different sectors of the Salado River basin. After La Niña event, the entire basin had the potential to revert to the previous density values, showing the resilience to global environmental changes and the ability to reestablish the general conditions of

  17. Phytoplankton chlorophyte structure as related to ENSO events in a saline lowland river (Salado River, Buenos Aires, Argentina).

    PubMed

    Solari, Lía C; Gabellone, Néstor A; Claps, María C; Casco, María A; Quaíni, Karina P; Neschuk, Nancy C

    2014-04-01

    We analyzed the phytoplankton present in the lower sector of the Salado River (Buenos Aires, Argentina) for 10 years (1995-2005) and detected significant changes occurring in chlorophyte abundance and species richness during La Niña event (1998-1999), which period was analyzed throughout the entire basin (main stream and tributaries). We compared the physicochemical and biologic variables between two El Niño-La Niña-Southern Oscillation (ENSO) periods - El Niño (March 1997-January 1998) and La Niña (May 1998-May 1999) - to identify possible indicators of a relationship between climatic anomalies and chlorophyte performance. Chlorophyte density increased during the La Niña. Under normal or extreme hydrologic conditions, mobile (Chlamydomonas spp.) and nonmobile (Monoraphidium spp.) chlorophytes codominated. These species belonged to Reynolds's functional groups X1 and X2, those typical of nutrient-enriched environments. Comparative analyses between El Niño and La Niña periods indicated significant differences in physicochemical (K(+), dissolved polyphenols, particulate reactive phosphorus, alkalinity, pH) and biologic (species diversity and richness, phytoplankton and chlorophyte total densities) variables between the two periods at all basin sites. During the La Niña condition, species richness was greater owing to interconnected shallow lakes and drainage-channel inputs, while the Shannon diversity index was lower because of the high abundance values of Monoraphidium minutum. A detailed analysis of the chlorophytes in the entire basin, indicated that changes in density and species dominance occurred on a regional scale although diverse chlorophyte assemblages were identified in the different sectors of the Salado River basin. After La Niña event, the entire basin had the potential to revert to the previous density values, showing the resilience to global environmental changes and the ability to reestablish the general conditions of stability.

  18. Groundwater dependence of coastal lagoons: The case of La Pletera salt marshes (NE Catalonia)

    NASA Astrophysics Data System (ADS)

    Menció, A.; Casamitjana, X.; Mas-Pla, J.; Coll, N.; Compte, J.; Martinoy, M.; Pascual, J.; Quintana, X. D.

    2017-09-01

    Coastal wetlands are among the most productive ecosystems of the world, playing an important role in coastal defense and wildlife conservation. These ecosystems, however, are usually affected by human activities, which may cause a loss and degradation of their ecological status, a decline of their biodiversity, an alteration of their ecological functioning, and a limitation of their ecosystem services. La Pletera salt marshes (NE Spain) are located in a region mainly dominated by agriculture and tourism activities. Part of these wetlands and lagoons has been affected by an incomplete construction of an urban development and in this moment is the focus of a Life+ project, whose aim is to restore this protected area. Several studies have analyzed the role of hydrological regime in nutrients, phytoplankton and zooplankton in this area, however, the role of groundwater was never considered as a relevant factor in the lagoon dynamics, and its influence is still unknown. In this study, the hydrogeological dynamics in La Pletera salt marshes has been analyzed, as a basis to set sustainable management guidelines for this area. In order to determine their dependence on groundwater resources, monthly hydrochemical (with major ions and nutrients) and isotopic (δ18OH2O and δD) campaigns have been conducted, from November 2014 to October 2015. In particular, groundwater from six wells, surface water from two nearby streams and three permanent lagoons, and sea water was considered in these surveys. Taking into account the meteorological data and the water levels in the lagoons, the General Lake Model has been conducted to determine, not only evaporation and rainfall occurring in the lagoons, but also the total inflows and outflows. In addition, the Gonfiantini isotopic model, together with equilibrium chemical-speciation/mass transfer models, has been used to analyze the evaporation and the physicochemical processes affecting the lagoons. Results show that during the dry

  19. Risk Assessment for the Explosive Washout Lagoons (Site 4), Umatilla Depot Activity Hermiston, Oregon

    DTIC Science & Technology

    1992-03-01

    Activity .............................. 2 2-2 Explosive Washout Lagoons (Site 4) and Washout Plant Area ............................... 2-3 3-1 Site 4...ponds for liquid wastes from bomb-washing operations in the washout plant . The measured dimensions of the flat bottoms of the two lagoons are 30 by 80...explosives washout plant system was drained, flushed, and cleaned approximately once each week from the mid-1950s until 1965. The lagoons received all of the

  20. Lagoon microbialites on Isla Angel de la Guarda and associated peninsular shores, Gulf of California (Mexico)

    NASA Astrophysics Data System (ADS)

    Johnson, Markes E.; Ledesma-Vázquez, Jorge; Backus, David H.; González, Maria R.

    2012-07-01

    Examples of two closed lagoons with extensive growth of Recent microbialites showing variable surface morphology and internal structure are found on Isla Angel de la Guarda in the Gulf of California. Comparable lagoonal microbialites also occur ashore from Ensenada El Quemado on the adjacent peninsular mainland of Baja California. The perimeters of all three lagoons feature crusted structures indicative of thrombolites with a knobby surface morphology 2 cm to 3 cm in relief and internal clotting without any sign of laminations. Outward from this zone, thrombolitic construction thins to merge with a white calcified crust below which a soft substratum of dark organic material 4 cm to 6 cm in thickness is concealed. The substratum is laminated and heavily mucilaginous, as observed along the edges of extensive shrinkage cracks in the overlying crust. The thrombolitic crust is anchored to the shore, while the thinner crust and associated stromatolitic mats float on the surface of the lagoons. Laboratory cultures of the dark organic material yielded the solitary cyanobacterium Chroococcidiopsis as the predominant taxon interspersed with filamentous forms. In decreasing order of abundance, other morphotypes present include Phormidium, Oscillatoria, Geitlerinema, Chroococus, and probably Spirulina. The larger of the two island lagoons follows an east-west azimuth and covers 0.225 km2, while the smaller lagoon has a roughly north-south axis and covers only 0.023 km2. The salinity of water in the smaller lagoon was measured as148 ppt. Pliocene strata along the edge of the smaller modern lagoon include siltstone bearing calcified platelets suggestive of a microbial origin. Dry lagoons abandoned during the later Quaternary occur inland at higher elevations on the island, but retain no fossils except for sporadic white crusts cemented on cobbles around distinct margins. Raised Quaternary lagoons parallel to the big lagoon on Isla Angel de la Guarda are partly obscured by flood

  1. Socio-economic appraisal of fishing community in Pulicat lagoon, south east coast of India: case study.

    PubMed

    Devi, V Vandhana; Krishnaveni, M

    2012-10-01

    Assessment of socio-economic issues of fishing community is an important aspect in framing a strategy for the preservation of eco-systems which leads to sustainable lagoon management. The present investigation analyses the current potential socio-economic status of the fishing community of Pulicat lagoon, the second largest lagoon in India. The socio-economic indicators considered in the study include demography, economic aspects, social aspects and occupation details. The relevant details were collected from 300 fisher folk family by conducting field survey through a well prepared questionnaire in the villages around Pulicat lagoon. The data analysis was done using Statistical Program for Social Sciences (SPSS) to assess the adequacy and precision of the collected data. The important and encouraging socio-economic indicators identified from the field survey for effective lagoon management includes significant presence of younger generation in the region; affinity and self-belongingness of fisher folk towards the lake; better economic status and moderate education level; appreciable fishing income and affinity towards fishing profession. It is emphasized to motivate the fisher folk to improve their work attitude for betterment in economic status. The pertinent lagoon issues, comprising seasonal variation, local fishing issues, pollution from industries, water intake to thermal power plant which directly or indirectly affects the socio-economic status of fishing community, also need much emphasis while proposing sustainable lagoon management system. The information and observation from this study will be very helpful in formulating management policies on the conservation of the Pulicat lagoon ecosystem.

  2. Watershed-scale drivers of air-water CO2 exchanges in two lagoonal, North Carolina (USA) estuaries

    NASA Astrophysics Data System (ADS)

    Van Dam, B.; Crosswell, J.; Anderson, I. C.; Paerl, H. W.

    2017-12-01

    Riverine loading of nutrients and organic matter act in concert to modulate CO2 fluxes in estuaries, yet quantitative relationships between these factors remain poorly defined. This study explored watershed-scale mechanisms responsible for the relatively low CO2 fluxes observed in two microtidal, lagoonal estuaries. Air-water CO2 fluxes were quantified with 74 high-resolution spatial surveys in the neighboring New River Estuary (NewRE) and Neuse River Estuary (NeuseRE), North Carolina, which experience a common climatology, but differ in marine versus riverine influence. Annually, both estuaries were relatively small sources of CO2 to the atmosphere, 12.5 and 16.3 mmol C m2 d-1 in the NeuseRE and NewRE, respectively. Variations in riverine alkalinity and inorganic carbon loading caused zones of minimum buffering capacity to occur at different locations in each estuary, enhancing the sensitivity of estuarine inorganic C chemistry to acidification. Large-scale pCO2 variations were driven by changes in freshwater age (akin to residence time), which modulate nutrient and organic carbon supply and phytoplankton flushing. Greatest pCO2 under-saturation was observed at intermediate freshwater ages, between 2-3 weeks. Biological controls on CO2 fluxes were obscured by variable inputs of river-borne CO2, which drove CO2 degassing in the river-dominated NeuseRE. Internally produced CO2 exceeded river-borne CO2 in the marine-dominated NewRE, suggesting that net ecosystem heterotrophy, rather than riverine inputs, drove CO2 fluxes in this system. Although annual CO2 fluxes were similar between systems, watershed-specific hydrologic factors led to disparate controls on internal carbonate chemistry, which can influence overall ecosystem health and response to future perturbation.

  3. Watershed-Scale Drivers of Air-Water CO2 Exchanges in Two Lagoonal North Carolina (USA) Estuaries

    NASA Astrophysics Data System (ADS)

    Van Dam, Bryce R.; Crosswell, Joseph R.; Anderson, Iris C.; Paerl, Hans W.

    2018-01-01

    Riverine loading of nutrients and organic matter act in concert to modulate CO2 fluxes in estuaries, yet quantitative relationships between these factors remain poorly defined. This study explored watershed-scale mechanisms responsible for the relatively low CO2 fluxes observed in two microtidal, lagoonal estuaries. Air-water CO2 fluxes were quantified with 74 high-resolution spatial surveys in the neighboring New River Estuary (NewRE) and Neuse River Estuary (NeuseRE), North Carolina, which experience a common climatology but differ in marine versus riverine influence. Annually, both estuaries were relatively small sources of CO2 to the atmosphere, 12.5 and 16.3 mmol C m-2 d-1 in the NeuseRE and NewRE, respectively. Large-scale pCO2 variations were driven by changes in freshwater age, which modulates nutrient and organic carbon supply and phytoplankton flushing. Greatest pCO2 undersaturation was observed at intermediate freshwater ages, between 2 and 3 weeks. Biological controls on CO2 fluxes were obscured by variable inputs of river-borne CO2, which drove CO2 degassing in the river-dominated NeuseRE. Internally produced CO2 exceeded river-borne CO2 in the marine-dominated NewRE, suggesting that net ecosystem heterotrophy, rather than riverine inputs, drove CO2 fluxes in this system. Variations in riverine alkalinity and inorganic carbon loading caused zones of minimum buffering capacity to occur at different locations in each estuary, enhancing the sensitivity of estuarine inorganic C chemistry to acidification. Although annual CO2 fluxes were similar between systems, watershed-specific hydrologic factors led to disparate controls on internal carbonate chemistry, which can influence ecosystem biogeochemical cycling, trophic state, and response to future perturbations.

  4. The atypical hydrodynamics of the Mayotte Lagoon (Indian Ocean): Effects on water age and potential impact on plankton productivity

    NASA Astrophysics Data System (ADS)

    Chevalier, C.; Devenon, J. L.; Pagano, M.; Rougier, G.; Blanchot, J.; Arfi, R.

    2017-09-01

    In mesotidal lagoons of the Indian Ocean, the coral reef barrier may be temporarily submerged at high tide and partially exposed at low tide, and this may cause unusual lagoon dynamics. A field measurement campaign was conducted in the north-east Mayotte Lagoon in order to understand these processes. An experimental approach was used, combining measurements taken by 1) a side-mounted Acoustic Doppler Current Profiler (ADCP) on a moving boat along transects through the reef passages (17 transects) and 2) by more conventional high-resolution moored ADCP measurements. A specific tidal analysis methodology was used to determine the spatial variability of the velocity. The tidal hydrodynamics within the lagoon were determined using a numerical model and then analyzed. The tide acted as a quasi-progressive forced wave in the lagoon: at low tide, water entered through the south passage, over the reef and left the lagoon through the north passage. This flow was reversed at high tide. The tide-driven quasi-progressive wave created a specific lagoon dynamics. Contrary to most other channel lagoons, the flow over the reef was mainly outward. This increases the inflow through the passages, which renews the water in the lagoon as shown by the indicators of age and origin of the water inside the lagoon. This study also showed the importance of these indicators for better understanding the variations and levels of plankton biomass (with chlorophyll concentration as proxy) which is quite high in this lagoon.

  5. Histology and gametogenesis in Heleobia piscium (Cochliopidae) from the Multiple Use Reserve “Isla Martín García,” Buenos Aires, Argentina

    PubMed Central

    Díaz, Ana C.

    2016-01-01

    Heleobia piscium (d’Orbigny, 1835), a member of the Cochliopidae family found only in South America, is distributed from Entre Ríos, Delta del Paraná, and the littoral of the Río de la Plata down as far as to Punta Indio (Buenos Aires), the southernmost limit of the snail’s geographical distribution. To date, little information is available regarding the reproductive cycle of species within this family either in Argentina or throughout South America. The present work analyzed the histology of the reproductive system of the gonochoric species H. piscium and determined the stages oogenesis and spermatogenesis under natural conditions. Specimens of H. piscium were collected in the Multiple-Use Natural Reserve Isla Martín García, located in the Upper Río de la Plata estuary to the south of the mouth of the Uruguay River. The gametogenic cycle in both sexes was found to consist of the following stages: early maturation, maturation, and evacuation. The maturation period was found to extend from January to October and evacuation of the gametes to start in November and end in February (summer in the Southern Hemisphere). The results indicated the H. piscium exhibit a reproductive cycle without a resting period. PMID:27761336

  6. Groundwater and porewater as major sources of alkalinity to a fringing coral reef lagoon (Muri Lagoon, Cook Islands)

    NASA Astrophysics Data System (ADS)

    Cyronak, T.; Santos, I. R.; Erler, D. V.; Eyre, B. D.

    2013-04-01

    To better predict how ocean acidification will affect coral reefs, it is important to understand how biogeochemical cycles on reefs alter carbonate chemistry over various temporal and spatial scales. This study quantifies the contribution of shallow porewater exchange (as quantified from advective chamber incubations) and fresh groundwater discharge (as traced by 222Rn) to total alkalinity (TA) dynamics on a fringing coral reef lagoon along the southern Pacific island of Rarotonga over a tidal and diel cycle. Benthic alkalinity fluxes were affected by the advective circulation of water through permeable sediments, with net daily flux rates of carbonate alkalinity ranging from -1.55 to 7.76 mmol m-2 d-1, depending on the advection rate. Submarine groundwater discharge (SGD) was a source of TA to the lagoon, with the highest flux rates measured at low tide, and an average daily TA flux of 1080 mmol m-2 d-1 at the sampling site. Both sources of TA were important on a reef-wide basis, although SGD acted solely as a delivery mechanism of TA to the lagoon, while porewater advection was either a sink or source of TA dependent on the time of day. This study describes overlooked sources of TA to coral reef ecosystems that can potentially alter water column carbonate chemistry. We suggest that porewater and groundwater fluxes of TA should be taken into account in ocean acidification models in order to properly address changing carbonate chemistry within coral reef ecosystems.

  7. Air quality assessment for land disposal of industrial wastes

    NASA Astrophysics Data System (ADS)

    Shen, Thomas T.

    1982-07-01

    Air pollution from hazardous waste landfills and lagoons is largely unknown. Routine monitoring of toxic air contaminants associated with hazardous waste facilities is difficult and very costly. The method presented in this paper would be useful for air quality assessment in the absence of monitoring data. It may be used as a screening process to examine the question of whether or not volatilization is considered to be significant for a given contaminant and also to evaluate permit applications for new hazardous waste facilities concerning waste volatilization problems.

  8. Evidence of North Africa’s Green Revolution Preserved in Sedimentary Organic Matter Deposited in Three Coastal Lagoons.

    EPA Science Inventory

    Because of longer residence times and limited mixing in coastal lagoons, the impacts of anthropogenic nutrient loading to lagoon food webs are often more pronounced than in other coastal ecosystems. For these reasons, many lagoons also provide an excellent environment for the dep...

  9. Decline of phosphorus, copper, and zinc in anaerobic lagoon columns receiving pretreated influent

    USDA-ARS?s Scientific Manuscript database

    Confined swine production generates large volumes of wastewater typically stored and treated in anaerobic lagoons. These lagoons usually require a sludge management plan for their maintenance consisting of regular sludge removal by mechanical agitation and pumping followed by land application at agr...

  10. The role of benthic macrophytes and their associated macroinvertebrate community in coastal lagoon resistance to eutrophication.

    PubMed

    Lloret, Javier; Marín, Arnaldo

    2009-12-01

    Eutrophication is widely recognised as one of the major menaces to coastal environments, particularly enclosed bays and lagoons. Although there is a general understanding of the consequences of eutrophication in these systems, there is a lack of sufficient knowledge concerning biotic feedbacks that influence eutrophication patterns and the resistance capacity of coastal environments. In this paper, the isotope ratios of main producers and consumers of a Mediterranean lagoon were examined in order to elucidate the fate of anthropogenic inputs from the main watercourse flowing into the lagoon. The results of the study of stable isotope data in the Mar Menor lagoon reflected that the whole benthic community plays an important role as a natural 'filter' that removes excess nutrients from the water column and stores them in the sediments, thereby enhancing lagoon resistance to eutrophication.

  11. Living in a coastal lagoon environment: photosynthetic and biochemical mechanisms of key marine macroalgae.

    PubMed

    García-Sánchez, Marta; Korbee, Nathalie; Pérez-Ruzafa, Isabel María; Marcos, Concepción; Figueroa, Félix L; Pérez-Ruzafa, Ángel

    2014-10-01

    The physiological status of Cystoseira compressa, Padina pavonica and Palisada tenerrima was studied by in vivo chlorophyll fluorescence, pigment content, stoichiometry (C:N), accumulation of UV photoprotectors and antioxidant activity; comparing their photosynthetic response in a coastal lagoon (Mar Menor) and in Mediterranean coastal waters. In general, the specimens reached their highest ETRmax in spring in the Lagoon, but in summer in the Mediterranean, coinciding with their maximum biomass peak. The species exhibited a dynamic photoinhibition. Except C. compressa, they showed a lower decrease in Fv/Fm and higher recovery rates in the Mediterranean populations when exposed to high irradiance. The higher salinity and temperature of the lagoon could impair the photoprotection mechanisms. The acclimation to lagoon environments is species-specific and involves complex regulatory mechanisms. The results underline the importance of N in repair, avoidance, quenching and scavenging mechanisms. In general, Lagoon specimens showed higher pigment concentration. Although xanthophylls play important photo-protective and antioxidant roles, the observed trend is more likely to be explained by the higher temperatures reached in the lagoon compared to Mediterranean. Therefore the studied photosynthetic and biochemical mechanisms can be effective not only for high irradiance, but also for higher temperatures in a climate change scenario, but are highly dependent on nutrient availability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. A Bayesian Network Model for Assessing Estrogen Fate and Transport in a Swine Waste Lagoon

    PubMed Central

    Lee, Boknam; Kullman, Seth W.; Yost, Erin; Meyer, Michael T.; Worley-Davis, Lynn; Reckhow, Kenneth H.

    2017-01-01

    Commercial swine waste lagoons are regarded as a major reservoir of natural estrogens, which have the potential to produce adverse physiological effects on exposed aquatic organisms and wildlife. However, there remains limited understanding of the complex mechanisms of physical, chemical, and biological processes that govern the fate and transport of natural estrogens within an anaerobic swine lagoon. To improve lagoon management and ultimately help control the offsite transport of these compounds from swine operations, a Bayesian network model was developed to predict estrogen fate and budget and compared against data collected from a commercial swine field site. In general, the model was able to predict the estrogen fate and budget in both the slurry and sludge stores within the swine lagoon. Sensitivity analysis within the model, demonstrated that the estrogen input loading from the associated barn facility was the most important factor in controlling estrogen concentrations within the lagoon slurry storage, while the settling rate was the most significant factor in the lagoon sludge storage. The degradation reactions were shown to be minor in both stores based on prediction of average total estrogen concentrations. Management scenario evaluations showed that the best possible management options to reduce estrogen levels in the lagoon are either to adjust the estrogen input loading from swine barn facilities or to effectively enhancing estrogen bonding with suspended solids through the use of organic polymers or inorganic coagulants. PMID:24798317

  13. Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico

    NASA Astrophysics Data System (ADS)

    Chuang, P.-C.; Young, M. B.; Dale, A. W.; Miller, L. G.; Herrera-Silveira, J. A.; Paytan, A.

    2017-05-01

    Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.

  14. Fingerprints of lagoonal life: Migration of the marine flatfish Solea solea assessed by stable isotopes and otolith microchemistry

    NASA Astrophysics Data System (ADS)

    Dierking, Jan; Morat, Fabien; Letourneur, Yves; Harmelin-Vivien, Mireille

    2012-06-01

    The commercially important marine flatfish common sole (Solea solea) facultatively uses NW Mediterranean lagoons as nurseries. To assess the imprint left by the lagoonal passage, muscle carbon (C) and nitrogen (N) isotope values of S. solea juveniles caught in Mauguio lagoon in spring (shortly after arrival from the sea) and in autumn (before the return to the sea) were compared with values of juveniles from adjacent coastal marine nurseries. In addition, in the lagoon, sole otolith stable isotope (C and oxygen (O)) and elemental (11 elements) composition in spring and autumn, and the stable isotope composition (C and N) of organic matter sources in autumn, were determined. Overall, our data indicate that a distinct lagoonal signature existed. Specifically, lagoon soles showed a strong enrichment in muscle tissue 15N (>6‰) compared to their coastal relatives, likely linked to sewage inputs (see below), and a depletion in 13C (1-2‰), indicative of higher importance of 13C depleted terrestrial POM in the lagoon compared to coastal nurseries. In addition, over the time spent in the lagoon, sole otolith δ13C and δ18O values and otolith elemental composition changed significantly. Analysis of the lagoon sole foodweb based on C and N isotopes placed sediment particulate organic matter (POM) at the base. Seagrasses, formerly common but in decline in Mauguio lagoon, played a minor role in the detritus cycle. The very strong 15N enrichment of the entire foodweb (+7 to +11‰) compared to little impacted lagoons and coastal areas testified of important human sewage inputs. Regarding the S. solea migration, the analysis of higher turnover and fast growth muscle tissue and metabolically inert and slower growth otoliths indicated that soles arrived at least several weeks prior to capture in spring, and that no migrations took place in summer. In the autumn, the high muscle δ15N value acquired in Mauguio lagoon would be a good marker of recent return to the sea, whereas

  15. Taphonomy of coral reefs from Southern Lagoon of Belize

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Westphall, M.J.; Ginsburg, R.N.

    1985-02-01

    The Southern Lagoon of the Belize barrier complex, an area of some 600 km/sup 2/, contains a tremendous number of lagoon reefs, which range in size from patches several meters across to rhomboidal-shaped structures several kilometers in their long dimension. These lagoon reefs are remarkable because they have Holocene sediment accumulations in excess of 13 m consisting almost entirely of coral debris and lime mud and sand, and rise up to 30 m above the surrounding lagoon floor with steeply sloping sides (50-80/sup 0/), yet are totally uncemented. The reef-building biota and their corresponding deposits were studied at a representativemore » reef, the rhomboidal complex of Channel Cay. As with many of the reefs in this area, the steeply sloping flanks of Channel Cay are covered mainly by the branched staghorn coral Acropora cervicornis and ribbonlike and platy growth of Agaricia spp. The living corals are not cemented to the substrate, but are merely intergrown. Fragmented pieces of corals accumulate with an open framework below the living community; this open framework is subsequently infilled by lime muds and sands produced mainly from bioerosion. Results from probing and coring suggest that the bafflestone fabric of coral debris and sediment extends at least 13 m into the subsurface. Radiocarbon-age estimates indicate these impressive piles of coral rubble and sediment have accumulated in the past 9000 yr (giving a minimum accumulation rate of 1.4 m/1000 yr) and illustrate the potential for significant carbonate buildups without the need for early lithification.« less

  16. A multimodal intervention to improve hand hygiene in ICUs in Buenos Aires, Argentina: a stepped wedge trial.

    PubMed

    Rodriguez, Viviana; Giuffre, Carolina; Villa, Silvia; Almada, Griselda; Prasopa-Plaizier, Nittita; Gogna, Monica; Gibbons, Luz; García Elorrio, Ezequiel

    2015-10-01

    Hand hygiene is a cost-effective measure to reduce microbial transmission (Teare EL, Cookson B, French GL, et al. UK handwashing initiative. J Hosp Infect. 1999;43:1-3.) and is considered to be the most important measure to prevent healthcare-associated infections (Pittet D, Allegranzi B, Sax H, Evidence-based model for hand transmission during patient care and the role of improved practices. Lancet Infect Dis 2006;6:641-52). Unfortunately, the compliance rate of healthcare workers (HCWs) with recommended hand hygiene procedures is less than expected. In order to estimate the effect of a multimodal intervention on improving healthcare workers' compliance with hand hygiene in eleven intensive care units (ICUs) from 11 hospitals of Buenos Aires, a randomized cluster-stepped wedge trial was designed. A multimodal intervention was designed based on practices characterized by being evidence-based, low cost and suggested by qualitative research: (i) leadership commitment, (ii) surveillance of materials needed to comply with hand hygiene and alcohol consumption, (iii) utilization of reminders, (iv) a storyboard of the project and (v) feedback (hand hygiene compliance rate). The study enrolled 705 participants, comprising nurses (66.4%), physicians (25.8%) and other HCW (7.8%) along 9 months of observation. Compliance with hand hygiene in the control group was 66.0% (2354/3565) vs. 75.6% (5190/6864) in the intervention group. Univariate analysis showed an association between the intervention and hand hygiene compliance (odds ratio, OR 1.17; 95% confidence interval (CI), 1.13-1.22). The effect was still present after adjustment by calendar's time and providers' characteristics-age, gender and profession (OR 1.08; 95% CI, 1.03-1.14). His study supports that a multimodal intervention was effective to improve compliance with hand hygiene in ICUs. © The Author 2015. Published by Oxford University Press in association with the International Society for Quality in Health Care

  17. Biodiversity patterns of macrophyte and macroinvertebrate communities in two lagoons of Western Greece.

    NASA Astrophysics Data System (ADS)

    Fyttis, G.; Reizopoulou, S.; Papastergiadou, E.

    2012-04-01

    Aquatic macrophytes and benthic macroinvertebrates were studied seasonally (Spring, Autumn, Summer) between the years 2009 - 2011 in two coastal lagoons (Kotychi and Prokopos) located in Peloponnese, Greece, in order to investigate spatial and temporal biodiversity trends related to hydrological processes (degree of confinement, nitrates, phosphates, chl-a, total suspended materials, light irradiance, pH, salinity, temperature and dissolved oxygen). Kotychi lagoon presents a better communication with the sea, while Prokopos has a high degree of confinement. Both ecosystems seasonally receive freshwater input from streams. The submerged aquatic macrophytes constituted a major component of the ecosystems studied. In total, 22 taxa of aquatic macrophytes (angiosperms and macroalgae), 16 taxa for Kotychi (2 Rhodophyta, 8 Chlorophyta, 5 Magnoliophyta, 1 Streptophyta) and 14 taxa for Prokopos (1 Rhodophyta, 5 Chlorophyta, 5 Magnoliophyta, 3 Streptophyta) were found. Ruppia cirrhosa, and Potamogeton pectinatus were dominant in both lagoons. Kotychi lagoon was also dominated by Zostera noltii and Prokopos by Zannichellia pallustris ssp. pedicellata, while the biomass of aquatic species peaked during the summer periods, in both lagoons. The total number of macroinvertebrates found in the lagoons was 28 taxa for Kotychi and 19 for Prokopos. Chironomidae were dominant in both lagoons, while Kotychi was also dominated by Lekanesphaera monodi and Monocorophium insidiosum, and Prokopos by Ostracoda and Lekanesphaera monodi. Benthic diversity ranged from 1.33 to 2.57 in Kotychi and from 0.67 to 2.48 in Prokopos. Species richness, diversity, and abundance of benthic macroinvertebrates were strongly related to aquatic vegetation and to the degree of communication with the marine environment. Moreover, species richness and abundance of both macrophytes and macroinvertebrates were mainly dependent on depth, temperature, pH and concentration of total suspended materials (TSM). Results

  18. Observations of emperor geese feeding at Nelson Lagoon, Alaska

    USGS Publications Warehouse

    Petersen, Margaret R.

    1983-01-01

    Estuaries along the north side of the Alaska Peninsula provide essential habitat for most of the American population of Emperor Goose (Chen canagica) during migration (Petersen and Gill 1982). Most of the population passes through Nelson Lagoon in spring and fall, with over 40,000 birds recorded there (Gill et al 1981). Little is known about the feeding activity of Emperor Geese while they are in estuaries, and the importance of estuaries as staging areas during spring and fall migration is poorly understood. Here I report observations on the feeding activity of emperor Geese at one estuary (Nelson Lagoon).

  19. HYDROBIOLOGICAL CHARACTERISTICS OF THE COASTAL LAGOONS AT HUGH TAYLOR BIRCH STATE RECREATION AREA, FORT LAUDERDALE, FLORIDA: A HISTORICAL PERSPECTIVE.

    USGS Publications Warehouse

    Brock, Robert J.

    1987-01-01

    The author presents initial results of an ongoing study of Southeast Florida coastal lagoon lakes. Objectives include presenting environmental conditions within and adjacent to the lagoons under a variety of hydrologic conditions and to determine water-quality changes in ground water and surface water and how these changes in water quality affect lagoonal biological communities within the lagoons.

  20. Parasite communities of the neotropical cormorant Phalacrocorax brasilianus (Gmelin) (Aves, Phalacrocoracidae) from two coastal lagoons in Guerrero state, Mexico.

    PubMed

    Violante-González, Juan; Monks, Scott; Gil-Guerrero, Salvador; Rojas-Herrera, Agustín; Flores-Garza, Rafael; Larumbe-Morán, Edvino

    2011-11-01

    The parasite community structure of the neotropical cormorant, Phalacrocorax brasilianus, from two lagoons (Coyuca and Tres Palos) from Guerrero state, México, was examined. Fourteen species of adult helminths (6,391 individuals) from 48 cormorants were identified: 9 digeneans, 1 acanthocephalan, 1 cestode, and 3 nematodes. A total of 11 species were collected in Coyuca Lagoon and 12 in Tres Palos Lagoon. Nine species co-occurred in cormorants of both lagoons but, with the exception of Contracaecum multipapillatum and Drepanocephalus olivaceus, species were not equally common in both lagoons. The prevalence values of six species of helminth and the mean abundance of four species varied significantly between lagoons, and C. multipapillatum was numerically dominant in both lagoons. The qualitative similarity between the two communities at the component level was 64%. All cormorants examined were infected, and parasite species richness was 3-5 in Coyuca and 4-9 in Tres Palos lagoon. The results indicate that both communities presented a similar structure at the component level, probably because the cormorants of both lagoons feed on the same species of fish and thus acquire almost the same species of parasites. Differences observed at the infracommunity level were attributed to variations in the degree of dominance of the particular species.

  1. Flushing of a polluted lagoon in Canc'un, using a SIBEO wave-driven seawater pump

    NASA Astrophysics Data System (ADS)

    Czitrom, Steven; Carbajal, Noel

    2006-11-01

    The coastal lagoon which adorns the seaside resort at Canc'un, Mexico, is heavily polluted as a result of decades of intense tourist activity development and overwhelmed inadequate planning. The natural flushing time of the lagoon, estimated at 2 to 4 years, is insufficient to cope with the waste that is being dumped and a thick layer of organic matter has accumulated on the lagoon bed. Appropriate legal and sewage treatment measures are imperative to curb further dumping and thus attack the root cause of the problem. This aside, however, the existing situation requires additional technical solutions to restore the ecosystem to a less altered state. A wave and tide driven seawater pump, invented and developed at the National University of Mexico, has been proposed to flush the lagoon with an average 0.2 m^3/s of clean and oxygen rich seawater from the neighboring ocean. This flow would reduce the residence time of the lagoon to around 6 months, promoting long term recovery of the ecosystem. The effect and distribution of the pumped water is being studied using a wind and tide driven 3D numerical model of the lagoon hydrodynamics. Some results from this study are presented here.

  2. Inhibition of microbial metabolism in anaerobic lagoons by selected sulfonamides, tetracyclines, lincomycin, and tylosin tartrate

    USGS Publications Warehouse

    Loftin, Keith A.; Henny, Cynthia; Adams, Craig D.; Surampali, Rao; Mormile, Melanie R.

    2005-01-01

    Antibiotics are used to maintain healthy livestock and to promote weight gain in concentrated animal feed operations. Antibiotics rarely are metabolized completely by livestock and, thus, are often present in livestock waste and in waste-treatment lagoons. The introduction of antibiotics into anaerobic lagoons commonly used for swine waste treatment has the potential for negative impacts on lagoon performance, which relies on a consortium of microbes ranging from fermentative microorganisms to methanogens. To address this concern, the effects of eight common veterinary antibiotics on anaerobic activity were studied. Anaerobic microcosms, prepared from freshly collected lagoon slurries, were amended with individual antibiotics at 10 mg/L for the initial screening study and at 1, 5, and 25 mg/L for the dose-response study. Monitored metabolic indicators included hydrogen, methane, and volatile fatty acid concentrations as well as chemical oxygen demand. The selected antibiotics significantly inhibited methane production relative to unamended controls, thus indicating that antibiotics at concentrations commonly found in swine lagoons can negatively impact anaerobic metabolism. Additionally, historical antibiotic usage seems to be a potential factor in affecting methane production. Specifically, less inhibition of methane production was noted in samples taken from the lagoon with a history of multiple-antibiotic use.

  3. Inhibition of microbial metabolism in anaerobic lagoons by selected sulfonamides, tetracyclines, lincomycin, and tylosin tartrate.

    PubMed

    Loftin, Keith A; Henny, Cynthia; Adams, Craig D; Surampali, Rao; Mormile, Melanie R

    2005-04-01

    Antibiotics are used to maintain healthy livestock and to promote weight gain in concentrated animal feed operations. Antibiotics rarely are metabolized completely by livestock and, thus, are often present in livestock waste and in waste-treatment lagoons. The introduction of antibiotics into anaerobic lagoons commonly used for swine waste treatment has the potential for negative impacts on lagoon performance, which relies on a consortium of microbes ranging from fermentative microorganisms to methanogens. To address this concern, the effects of eight common veterinary antibiotics on anaerobic activity were studied. Anaerobic microcosms, prepared from freshly collected lagoon slurries, were amended with individual antibiotics at 10 mg/L for the initial screening study and at 1, 5, and 25 mg/L for the dose-response study. Monitored metabolic indicators included hydrogen, methane, and volatile fatty acid concentrations as well as chemical oxygen demand. The selected antibiotics significantly inhibited methane production relative to unamended controls, thus indicating that antibiotics at concentrations commonly found in swine lagoons can negatively impact anaerobic metabolism. Additionally, historical antibiotic usage seems to be a potential factor in affecting methane production. Specifically, less inhibition of methane production was noted in samples taken from the lagoon with a history of multiple-antibiotic use.

  4. Sludge reduction and water quality improvement in anaerobic lagoons through influent pre-treatment

    USDA-ARS?s Scientific Manuscript database

    Confined swine production generates large volumes of wastewater typically stored and treated in anaerobic lagoons. These lagoons may require cleanup and closure measures in the future. In practice, liquid and sludge need to be removed by pumping, usually at great expense of energy, and land applied ...

  5. Developing a model for the mercury cycle in the Marano-Grado Lagoon (Italy)

    EPA Science Inventory

    The Marano-Grado Lagoon is a wetland system of about 160 km2 located in the Northern Adriatic Sea (Italy) between the Tagliamento and the Isonzo River mouths. The lagoon morphology and biogeochemistry are primarily controlled by the exchange with the Adriatic Sea and, to a lesser...

  6. The role of connectivity and hydrodynamic conditions in the configuration of ichthyoplankton assemblages in coastal lagoons

    NASA Astrophysics Data System (ADS)

    Pérez-Ruzafa, Angel; Quispe, Jhoni I.; Umgiesser, Georg; Ghezzo, Michol; De Pascalis, Francesca; Marcos, Concepción

    2014-05-01

    Fish assemblages in coastal lagoons are constituted by species with different gilds and life stories including estuarine residents but also a high percentage of marine stragglers and marine migrants. Previous studies showed that different ichthyoplancton assemblages can be identified inside a lagoon, depending on hydrological conditions, but at the same time a high spatial and temporal variability haven observed. The proposed models to explain lagoon assemblages configuration based on probabilities of colonization from the open sea involves an important stochastic component and introduces some randomness that could lead to that high spatial and temporal variability at short and long-term scales. In this work we analyze the relationship between ichthyoplankton assemblages in the Mar Menor lagoon and the adjacent open sea in the framework of the hydrodynamics of the lagoon and connectivity between sampling stations using hydrodynamic models. The results, show a complex interaction between the different factors that lead to a highly variable system with high accumulated richness and diversity of species, and a large proportion of occasional visitors and stragglers suggesting that the mechanisms of competitive lottery can play an important role in the maintenance of communities of coastal lagoons , where environmental variability occurs in a system with strong differences in colonization rates and connectivity, not only with the open sea, but also between locations within the lagoon.

  7. CISOCUR - Hydrodynamic circulation in the Curonian Lagoon inferred through stable isotope measurements and numerical modelling

    NASA Astrophysics Data System (ADS)

    Umgiesser, Georg; Razinkovas-Baziukas, Arturas; Barisevičiūtė, Ruta; Baziukė, Dalia; Ertürk, Ali; Gasiūnaitė, Jovita; Gulbinskas, Saulius; Lubienė, Irma; Maračkinaite, Jurgita; Petkuvienė, Jolita; Pilkaitytė, Renata; Ruginis, Tomas; Zemlys, Petras; Žilius, Mindaugas

    2013-04-01

    The spatial pattern of the hydrodynamic circulation of the Curonian lagoon, the largest European coastal lagoon, is still little understood. In absence of automatic current registration data all the existing models relied mostly on such data as water levels leaving high level of uncertainty. Here we present CISOCUR, a new project financed by the European Social Fund under the Global Grant measure. The project applies a new methodology that uses the carbon stable isotope (SI) ratio of C12 and C13 that characterize different water sources entering the lagoon and may be altered by internal kinetic processes. Through the tracing of these isotope ratios different water masses can be identified. This gives the possibility to validate several hypotheses of water circulation and validate hydrodynamic models. In particular it will be possible to 1) trace water masses entering the lagoon through the Nemunas and the Klaipeda strait; 2) test the hypothesis of sediment transport mechanisms inside the lagoon; 3) evaluate the importance of physical forcing on the lagoon circulation. The use of a hydrodynamic finite element model, coupled with the SI method, will allow for a realistic description of the transport processes inside the Curonian lagoon. So the main research goal is to apply the stable isotope tracers and a finite element model to determine the circulation patterns in the Curonian lagoon. Overall, the project will develop according to 4 main phases: 1) A pilot study to measure the isotope composition of different carbon compounds (dissolved and suspended) in different water bodies that feed water into the central lagoon. Through this pilot study the optimal study sites for the seasonal campaign will be identified as well. 2) Seasonal field campaigns in the monitoring stations identified in phase 1 to measure the carbon isotope ratio. 3) Development of a model that describes the kinetics of carbon isotopes and its transformation. 4) Application of a hydrodynamic model

  8. Metazoan parasites of fishes from the Celestun coastal lagoon, Yucatan, Mexico.

    PubMed

    Sosa-Medina, Trinidad; Vidal-Martínez, Víctor M; Aguirre-Macedo, M Leopoldina

    2015-08-31

    The aims of this study were to produce a checklist of the metazoan parasites of fishes from the Celestun coastal lagoon and to determine the degree of faunal similarity among the fishes based on the metazoan parasites they share. A checklist was prepared including all available records (1996-2014) of parasites of marine, brackish water and freshwater fishes of the area. All of these data were included in a presence/absence database and used to determine similarity via Jaccard's index. The results indicate the presence of 62 metazoan parasite species infecting 22 fish species. The number of metazoan parasite species found in the fishes from the Celestún lagoon is apparently the highest reported worldwide for a tropical coastal lagoon. The parasites included 12 species of adult digeneans, 27 digeneans in the metacercarial stage, 6 monogeneans, 3 metacestodes, 9 nematodes, 2 acanthocephalans, 2 crustaceans and 1 annelid. Forty parasite species were autogenic and 23 were allogenic and 1 unknown. The overall similarity among all of the species of fish with respect to the metazoan parasites they share was low (0.08 ± 0.12), with few similarity values above 0.4 being obtained. This low similarity was due primarily to the presence of suites of parasites exclusive to specific species of fish. The autogenic component of the parasite fauna (40 species) dominated the allogenic component (21 species). The most likely explanation for the large number of fish parasites found at Celestún is the good environmental condition of the lagoon, which allows the completion of parasite life cycles and free circulation of euryhaline fishes from the marine environment bringing marine parasites into the lagoon.

  9. Sediment characteristics and water quality in the two hyper-saline lagoons along the Red Sea coast of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Rasul, Najeeb; Al-Farawati, Radwan; Al-Harbi, Omer; Naser Qutub, Abdul

    2013-04-01

    The two hyper-saline Shoaiba lagoons, Khawr ash Shaibah al Masdudah (northern lagoon) and Khawr ash Shaibah al Maftuhah (southern lagoon) have a unique environmental set-up because no rivers or wadis flow into the lagoons and therefore detrital material to the lagoons is lacking and most of the sediments are indigenous carbonates. The biogenic material is mostly derived from coral debris, coralline algae and molluscs abundant in gravel and sand size fractions. The evaporite deposits from the adjoining sabkhas are transported to the lagoon during tidal cycles. Carbonate is abundant in the form of aragonite and High Mg-calcite indicating carbonate to be recent and formed under shallow water conditions. In general, the sediments are the result of the mechanical breakdown of molluscs and coral reefs by either human activity or by coral boring marine organisms and physical processes such as tidal and wind generated currents. Strong currents dominate only the deeper part at the entrance of the lagoons that causes the winnowing of the finer sediments, and its transportation during flooding and ebbing. Shallow depths averaging 3 m, wind and tidal stirring are the main forces preventing the lagoons from developing stratification resulting in a well-mixed body of water. The shallow depth of the lagoons keep the turbidity levels higher, whereas salinity as high as 52 ‰ and water temperature as high as 38 °C helps in the formation of halite at the periphery. The cyclical inundation of sabkhas by a thin sheet of water during tidal cycles is important in understanding the ecological consequence. Mangrove stands in the lagoons act as a source of nutrients to the flora and fauna inhabiting the lagoons. The configurations of the mouth of the lagoons influence the tidal currents, including the sediment and water movement. The tidal current is enhanced as it enters the lagoons, in response to the funneling effect caused by the narrow channel. The current diffuses as the entrance

  10. Into the Depths of the Lagoon Nebula

    NASA Image and Video Library

    2011-09-16

    Swirling dust clouds and bright newborn stars dominate the view in this image of the Lagoon nebula from NASA Spitzer Space Telescope. The nebula lies in the general direction of the center of our galaxy in the constellation Sagittarius.

  11. Test plan, the Czechowice Oil Refinery bioremediation demonstration of a process waste lagoon. Revision 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Altman, D.J.; Hazen, T.C.; Tien, A.J.

    1997-05-10

    The overall objective of the bioremediation project is to provide a cost effective bioremediation demonstration of petroleum contaminated soil at the Czechowice Oil Refinery. Additional objectives include training of personnel, and transfer of this technology by example to Poland, and the Risk Abatement Center for Central and Eastern Europe (RACE). The goal of the remediation is to reduce the risk of PAH compounds in soil and provide a green zone (grassy area) adjacent to the site boundary. Initial project discussions with the Czechowice Oil Refinery resulted in helping the refinery find an immediate cost effective solution for the dense organicmore » sludge in the lagoons. They found that when mixed with other waste materials, the sludge could be sold as a fuel source to local cement kilns. Thus the waste was incinerated and provided a revenue stream for the refinery to cleanup the lagoon. This allowed the bioremediation project to focus on remediation of contaminated soil that unusable as fuel, less recalcitrant and easier to handle and remediate. The assessment identified 19 compounds at the refinery that represented significant risk and would require remediation. These compounds consisted of metals, PAH`s, and BTEX. The contaminated soil to be remediated in the bioremediation demonstration contains only PAH (BTEX and metals are not significantly above background concentrations). The final biopile design consists of (1) dewatering and clearing lagoon A to clean clay, (2) adding a 20 cm layer of dolomite with pipes for drainage, leachate collection, air injection, and pH adjustment, (3) adding a 1.1 m layer of contaminated soil mixed with wood chips to improve permeability, and (4) completing the surface with 20 cm of top soil planted with grass.« less

  12. Tidal dynamics in a changing lagoon: Flooding or not flooding the marginal regions

    NASA Astrophysics Data System (ADS)

    Lopes, Carina L.; Dias, João M.

    2015-12-01

    Coastal lagoons are low-lying systems under permanent changes motivated by natural and anthropogenic factors. Ria de Aveiro is such an example with its margins currently threatened by the advance of the lagoonal waters recorded during the last decades. This work aims to study the tidal modifications found between 1987 and 2012 in this lagoon, motivated by the main channels deepening which induce higher inland tidal levels. Additionally it aims to study the impact that protective walls designed to protect the margins against flooding may have in those modifications under sea level rise predictions. The hydrodynamic model ELCIRC previously calibrated for Ria de Aveiro was used and tidal asymmetry, tidal ellipses and residual currents were analyzed for different scenarios, considering the mean sea level rise predicted for 2100 and the implementation of probable flood protection walls. Results evidenced that lagoon dominance remained unchanged between 1987 and 2012, but distortion decreased/increased in the deeper/shallower channels. The same trend was found under mean sea level rise conditions. Tidal currents increased over this period inducing an amplification of the water properties exchange within the lagoon, which will be stronger under mean sea level rise conditions. The deviations between scenarios with or without flood protection walls can achieve 60% for the tidal distortion and residual currents and 20% for the tidal currents, highlighting that tidal properties are extremely sensitive to the lagoon geometry. In summary, the development of numerical modelling applications dedicated to study the influence of mean sea level rise on coastal low-lying systems subjected to human influence should include structural measures designed for flood defence in order to accurately predict changes in the local tidal properties.

  13. A Trophic Model of a Sandy Barrier Lagoon at Chiku in Southwestern Taiwan

    NASA Astrophysics Data System (ADS)

    Lin, H.-J.; Shao, K.-T.; Kuo, S.-R.; Hsieh, H.-L.; Wong, S.-L.; Chen, I.-M.; Lo, W.-T.; Hung, J.-J.

    1999-05-01

    Using the ECOPATH 3.0 software system, a balanced trophic model of a sandy barrier lagoon with intensive fishery activities at Chiku in tropical Taiwan was constructed. The lagoon model comprised 13 compartments. Trophic levels of the compartments varied from 1·0 for primary producers and detritus to 3·6 for piscivorous fish. Hanging-cultured oysters accounted for 39% of the harvestable fishery biomass and were the most important fishery species. The most prominent group in terms of biomass and energy flow in the lagoon was herbivorous zooplankton. Manipulations of the biomass of herbivorous zooplankton would have a marked impact on most compartments. Both total system throughput and fishery yield per unit area were high when compared to other reported marine ecosystems. This appears mainly due to high planktonic primary production, which is probably promoted by enriched river discharges draining mangroves and aquaculture ponds. Consequently, more than half of the total system throughput originates from primary producers in the lagoon. Although half of the primary production was not immediately used by upper trophic levels and flowed into the detrital pool, most of the detritus was directly consumed, passed up the food web and was exported to the fishery. Thus only a small proportion of energy was recycled through detritus pathways. This mechanism produces short pathways with high trophic efficiencies at higher trophic levels. The high fishery yield in the lagoon is due to high primary production and short pathways. This is the first model of a tropical sandy barrier lagoon with intensive fishery activities and thus may serve as a basis for future comparisons and ecosystem management.

  14. Biodegradation of hexadecane using sediments from rivers and lagoons of the Southern Gulf of Mexico.

    PubMed

    García-Cruz, N Ulises; Sánchez-Avila, Juan I; Valdés-Lozano, David; Gold-Bouchot, Gerardo; Aguirre-Macedo, Leopoldina

    2018-03-01

    The Southern Gulf of Mexico is an area highly impacted by crude oil extraction, refining activities and the presence of natural petroleum seepage. Oceanic currents in the Gulf of Mexico continually facilitate the transport of hydrocarbons to lagoons and rivers. This research evaluated hexadecane (HXD) degradation in marine sediment samples from lagoons and rivers that are fed by the Southern Gulf of Mexico, specifically six samples from rivers, three samples from lagoons, and one sample from a marine outfall. The highest rates of biodegradation were observed in sediments from the mouths of the Gonzalez River and the Champotón Lagoon. The lowest consumption rate was found in sediment from the mouth of the Coatzacoalcos River. With regards to the Ostión Lagoon and the Grijalva River, there was a low rate of consumption, but a high efficiency of degradation which took place at the end of the experiments. No correlation was found between the consumption rate and the environmental physicochemical parameters. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Meiobenthic communities in permanently open estuaries and open/closed coastal lagoons of Uruguay (Atlantic coast of South America)

    NASA Astrophysics Data System (ADS)

    Kandratavicius, N.; Muniz, P.; Venturini, N.; Giménez, L.

    2015-09-01

    This study aimed to determine if estuarine meiofaunal communities of Uruguay (South America) vary between permanently open estuaries and open/closed coastal lagoons, or if they respond to the sediment composition. In Uruguay, estuaries and coastal lagoons vary in the degree of connectivity to the sea and in the sediment composition; sediments in estuaries are characterized by fine-medium sands but sediments vary from lagoon to lagoon (either fine-medium or coarse sand). Taxa richness (total = 16) showed less temporal variability in lagoons than in estuaries, due to patterns of presence/absence of the less abundant taxa. However, no major response to habitat was found in the most abundant groups: polychaetes (6% of total fauna) were on average 5% more abundant in lagoons than in estuaries. Some level of zonation, within estuaries and lagoons, was found in the most abundant groups, nematodes (63% of total fauna) and copepods (15%) in response to medium and fine sands. In addition, sediment type modulated seasonal patterns in the frequency of presence/absence in ostracods, polychaetes and oligochaetes. For instance, in polychaetes and ostracods the increase in the frequency of absences, occurring from summer to winter, was stronger in lagoons and estuaries dominated by fine sands. The lagoon habitat appears to ameliorate the effects of unfavourable (winter) conditions in less abundant meiofaunal taxa. In summary, sediment fractions explain spatial patterns in the average abundance of organisms (e.g. nematodes) as well as the seasonal changes in frequency of presence/absence (e.g. polychaetes).

  16. Spatial variation of acid-volatile sulfide and simultaneously extracted metals in Egyptian Mediterranean Sea lagoon sediments.

    PubMed

    Younis, Alaa M; El-Zokm, Gehan M; Okbah, Mohamed A

    2014-06-01

    In risk assessment of aquatic sediments, the immobilizing effect of acid-volatile sulfide (AVS) on trace metals is a principal control on availability and associated toxicity of metals to aquatic biota, which reduces metal bioavailability and toxicity by binding and immobilizing metals as insoluble sulfides. Spatial variation pattern of AVS, simultaneously extracted metals (SEM), and sediment characteristics were studied for the first time in surface sediment samples (0-20 cm) from 43 locations in Egyptian northern delta lagoons (Manzalah, Burullus, and Maryut) as predictors of the bioavailability of some divalent metals (Cu, Zn, Cd, Pb, and Ni) in sediments as well as indicators of metal toxicity in anaerobic sediments. The results indicated that the ∑SEM (Cu + Zn + Cd + Pb + Ni) values in sediments of lagoon Burullus had higher concentrations than those of Maryut and Manzalah. In contrast, AVS concentrations were considerably higher in lagoons Manzalah and Maryut and seemed to be consistent with the increase in organic matter than lagoon Burullus. Generally, the average concentrations of the SEM in all lagoons were in the order of Zn > Cu > Ni > Pb > Cd. The ratios of ∑SEM/AVS were less than 1 at all the sampling stations except at one station in lagoon Maryut as well as four stations located in lagoon Burullus (∑SEM/AVS > 1), which suggests that the metals have toxicity potential in these sediments. Therefore, SEM concentrations probably are better indicators of the metal bioavailability in sediments than the conventional total metal concentrations.

  17. Vadose Zone Monitoring of Dairy Green Water Lagoons using Soil Solution Samplers.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brainard, James R.; Coplen, Amy K

    2005-11-01

    Over the last decade, dairy farms in New Mexico have become an important component to the economy of many rural ranching and farming communities. Dairy operations are water intensive and use groundwater that otherwise would be used for irrigation purposes. Most dairies reuse their process/green water three times and utilize lined lagoons for temporary storage of green water. Leakage of water from lagoons can pose a risk to groundwater quality. Groundwater resource protection infrastructures at dairies are regulated by the New Mexico Environment Department which currently relies on monitoring wells installed in the saturated zone for detecting leakage of wastemore » water lagoon liners. Here we present a proposal to monitor the unsaturated zone beneath the lagoons with soil water solution samplers to provide early detection of leaking liners. Early detection of leaking liners along with rapid repair can minimize contamination of aquifers and reduce dairy liability for aquifer remediation. Additionally, acceptance of vadose zone monitoring as a NMED requirement over saturated zone monitoring would very likely significantly reduce dairy startup and expansion costs. Acknowledgment Funding for this project was provided by the Sandia National Laboratories Small Business Assistance Program« less

  18. Optical researches for cyanobacteria bloom monitoring in Curonian Lagoon

    NASA Astrophysics Data System (ADS)

    Shirshin, Evgeny A.; Budylin, Gleb B.; Yakimov, Boris P.; Voloshina, Olga V.; Karabashev, Genrik S.; Evdoshenko, Marina A.; Fadeev, Victor V.

    2016-04-01

    Cyanobacteria bloom is a great ecological problem of Curonian Lagoon and Baltic Sea. The development of novel methods for the on-line control of cyanobacteria concentration and, moreover, for prediction of bloom spreading is of interest for monitoring the state of ecosystem. Here, we report the results of the joint application of hyperspectral measurements and remote sensing of Curonian Lagoon in July 2015 aimed at the assessment of cyanobacteria communities. We show that hyperspectral data allow on-line detection and qualitative estimation of cyanobacteria concentration, while the remote sensing data indicate the possibility of cyanobacteria bloom detection using the spectral features of upwelling irradiation.

  19. Late Holocene sedimentation in a high Arctic coastal setting: Simpson Lagoon and Colville Delta, Alaska

    NASA Astrophysics Data System (ADS)

    Hanna, Andrea J. M.; Allison, Mead A.; Bianchi, Thomas S.; Marcantonio, Franco; Goff, John A.

    2014-02-01

    Arctic coastal environments near major river outfalls, like Simpson Lagoon, Alaska and the adjacent Colville River Delta, potentially contain high-resolution sediment records useful in elucidating late Holocene Arctic sediment transport pathways and coupled terrestrial-ocean evidence of paleoclimate variability. This study utilizes a multi-tracer geochronology approach (137Cs, 239,240Pu, and 14C) tailored for high-latitude environments to determine the age models for cores collected from Simpson Lagoon, and to date seismic boundaries in shallow acoustic reflection data (CHIRP) to examine late Holocene infill patterns. Modern (~100 y) sediment accumulation rates range from <0.02 to 0.46±0.04 cm y-1, with a primary depocenter in western Simpson Lagoon adjacent to the Colville Delta and a secondary depocenter in eastern Simpson Lagoon. CHIRP reflectors, age-constrained by 14C analysis, reveal rapid late Holocene (0-3500 y BP) transgression consistent with high modern shoreline retreat rates. The western depocenter contains >5 m of late Holocene interbedded sediments, likely derived primarily from the Colville River, with onset of accumulation occurring prior to ~3500 y BP. A paleo-high in central Simpson Lagoon, separating the two depocenters, was subaerially exposed prior to ~600 y BP. The millimeters-per-year sedimentation rates across the lagoon, coupled with the undisturbed, interbedded sediment record, indicate that these settings hold great potential to develop new Arctic paleoenvironmental records.

  20. Acid Tar Lagoons: Management and Recovery

    NASA Astrophysics Data System (ADS)

    Bohers, Anna; Hroncová, Emília; Ladomerský, Juraj

    2017-04-01

    This contribution presents the issue with possibility of definitive removal of dangerous environmental burden in Slovakia - serious historical problem of two acid tar lagoons. In relation to their removal, no technology has been found so far - technologically and economically suitable, what caused problems with its management. Locality Predajná is well known in Slovakia by its character of contrasts: it is situated in the picturesque landscape of National Park buffer zone of Nízke Tatry, on the other site it is contaminated by 229 211m3 of acid tar with its characteristics of toxicity, carcinogenicity, teratogenicity, mutagenicity and toxicity especially for animals and plants. Acid tar in two landfills with depth of 1m in case of the first lagoon and 9,5m in case of the second lagoon is a waste product derived from operation of Petrochema Dubová - refinery and petrochemical plant whose activity was to process the crude oil through processes of sulfonation and adsorption technology for producing lubricating and special oils, synthetic detergents and special white oils for cosmetic and medical purposes. A part of acid tar was incinerated in two incineration plats. Concentration of SO2 in combustion gases was too high and it was not possible to decrease it under the value of 2000 mg.mn-3 [LADOMERSKÝ, J. - SAMEŠOVÁ, D.: Reduction in sulfur dioxide emissions waste gases of incineration plant. Acta facultatis ecologiae. 1999, p. 217-223]. That is why it was necessary to put them out of operation. Later, because of public opposition it was not possible to build a new incineration plat corresponding to the state of the art. Even though actual Slovak and European legislative for protection of environment against such impacts, neither of tried methods - bio or non-biologic treatment methods - was proved as suitable for processing or for recovery in the reason of different factors admission: i.e. strong aggressivity, difficulty with handling because of its sludgy and

  1. Assessment of temporal and spatial water quality in international Gomishan Lagoon, Iran, using multivariate analysis.

    PubMed

    Basatnia, Nabee; Hossein, Seyed Abbas; Rodrigo-Comino, Jesús; Khaledian, Yones; Brevik, Eric C; Aitkenhead-Peterson, Jacqueline; Natesan, Usha

    2018-04-29

    Coastal lagoon ecosystems are vulnerable to eutrophication, which leads to the accumulation of nutrients from the surrounding watershed over the long term. However, there is a lack of information about methods that could accurate quantify this problem in rapidly developed countries. Therefore, various statistical methods such as cluster analysis (CA), principal component analysis (PCA), partial least square (PLS), principal component regression (PCR), and ordinary least squares regression (OLS) were used in this study to estimate total organic matter content in sediments (TOM) using other parameters such as temperature, dissolved oxygen (DO), pH, electrical conductivity (EC), nitrite (NO 2 ), nitrate (NO 3 ), biological oxygen demand (BOD), phosphate (PO 4 ), total phosphorus (TP), salinity, and water depth along a 3-km transect in the Gomishan Lagoon (Iran). Results indicated that nutrient concentration and the dissolved oxygen gradient were the most significant parameters in the lagoon water quality heterogeneity. Additionally, anoxia at the bottom of the lagoon in sediments and re-suspension of the sediments were the main factors affecting internal nutrient loading. To validate the models, R 2 , RMSECV, and RPDCV were used. The PLS model was stronger than the other models. Also, classification analysis of the Gomishan Lagoon identified two hydrological zones: (i) a North Zone characterized by higher water exchange, higher dissolved oxygen and lower salinity and nutrients, and (ii) a Central and South Zone with high residence time, higher nutrient concentrations, lower dissolved oxygen, and higher salinity. A recommendation for the management of coastal lagoons, specifically the Gomishan Lagoon, to decrease or eliminate nutrient loadings is discussed and should be transferred to policy makers, the scientific community, and local inhabitants.

  2. Assessing hydrological effects of human interventions on coastal systems: numerical applications to the Venice Lagoon

    NASA Astrophysics Data System (ADS)

    Ferrarin, C.; Ghezzo, M.; Umgiesser, G.; Tagliapietra, D.; Camatti, E.; Zaggia, L.; Sarretta, A.

    2012-12-01

    The hydrological consequences of historical, contemporary and future human activities on a coastal system were investigated by means of numerical models. The changes in the morphology of the Lagoon of Venice during the last century result from the sedimentological response to the combined effects of human interventions on the environment and global changes. This study focuses on changes from 1927 to 2012 and includes the changes planned for the protection of the city of Venice from storm surges and exceptional tides under future sea level rise scenarios. The application of a hydrodynamic model to simulate the circulation of water masses and the transport of a passive tracer enabled the analysis of the morphodynamic effects on the lagoon circulation and the interaction with the sea. The absolute values of the exchange between the lagoon and sea increased from 1927 to 2002 (from 3900 to 4600 m3 s-1), while the daily fraction of lagoon water volume exchanged decreased. At the same time, the water renewal time shortened from 11.9 to 10.8 days. Morphological changes during the last decade induced an increase of the basin-wide water renewal time (from 10.8 to 11.3 days). In the future, Venice Lagoon will evolve to a more restricted environment due to sea level rise and periodical closure of the lagoon from the sea during flooding events. Simulated scenarios of sea level rise showed that under fall-winter conditions the water renewal time will increased considerably especially in the central part of the lagoon. Furthermore, some considerations on the impact of the hydromorphological changes on the ecological dynamics are proposed.

  3. Toward a Model Based-Bayesian Theory for Estimating and Recognizing Parameterized 3-D Objects Using Two or More Images Taken from Different Positions

    DTIC Science & Technology

    1989-10-01

    Aires, and Philips Laboratory at Briarcliff, NY. B. Cernuschi-Frias is with Facultad de Ingenieria , Universidad de Buenos Aires, Buenos Aires... Ingenieria , Universidad de Buenos Aires, and from IBM (Thomas J. Watson Research Center). David B. Cooper (S’53-M’64) received the B.Sc. and Sc.M

  4. Lagoons and Reefs of New Caledonia

    NASA Image and Video Library

    2011-04-20

    NASA image acquired May 10, 2001 In July 2008, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) added 27 new areas to its list of World Heritage sites. One of those areas included the lagoons of New Caledonia. Some 1,200 kilometers (750 miles) east of Australia, this French-governed archipelago contains the world’s third-largest coral reef structure. The coral reefs enclose the waters near the islands in shallow lagoons of impressive biodiversity. On May 10, 2001, the Enhanced Thematic Mapper Plus on NASA’s Landsat 7 satellite captured this image of Île Balabio, off the northern tip of Grande Terra, New Caledonia’s main island. In this natural-color image, the islands appear in shades of green and brown—mixtures of vegetation and bare ground. The surrounding waters range in color from pale aquamarine to deep blue, and the color differences result from varying depths. Over coral reef ridges and sand bars, the water is shallowest and palest in color. Darker shades of blue characterize deeper waters. Reef-enclosed, shallow waters surround Île Balabio, and a larger, semi-enclosed lagoon appears immediately east of that island. Immediately north of Grande Terra, unenclosed, deeper waters predominate. The coral reefs around New Caledonia support an unusual diversity of species, including large numbers of predators and big fish, turtles, and the world’s third-largest dugong population. NASA image created by Jesse Allen, using Landsat data provided by the United States Geological Survey. Caption by Michon Scott. Instrument: Landsat 7 - ETM+ Credit: NASA/GSFC/Landsat NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

  5. Stage-specific distribution models can predict eel (Anguilla anguilla) occurrence during settlement in coastal lagoons

    NASA Astrophysics Data System (ADS)

    Leone, C.; Zucchetta, M.; Capoccioni, F.; Gravina, M. F.; Franzoi, P.; Ciccotti, E.

    2016-03-01

    Eel (Anguilla anguilla) is a catadromous fish species typical of Mediterranean coastal lagoons, that currently suffers from several anthropogenic and natural impacts. These are thought to be the cause of a stock-wide decline that this panmictic species is facing, in inland and coastal waters of Europe and North Africa. The decline affects both adult phases and recruitment, i.e. glass eel arrival to coastal waters and their ascent to inland waters. Quantitative features of eel recruitment reflect a transoceanic global scale, but also depend on local environmental conditions, the latter also affecting settlement dynamics in transitional waters. There is only little information on the dynamics of these two processes in coastal lagoons, notwithstanding the paramount importance of both in sustaining local stocks abundance and their demographic structure for this typical but also economically important inhabitant of Mediterranean lagoons, habitats that constitute an important share of the eel distribution area. The present study aims, therefore, to clarify space and time dynamics of local scale recruitment and of settlement in a coastal lagoon in the Mediterranean area, also by setting up a specific methodological approach. For this purpose, data from field surveys in combination with Species Distribution Models (SDMs) have been used in order to relate distribution of eel juvenile stages to the environmental conditions within the lagoon. Specifically, models were calibrated to quantify the relationship between presence of juvenile eel and the main environmental drivers, with the aim of identifying potential habitats for eel settlement within the lagoon. Results gained by modelling suggest certain spatial and temporal colonization patterns for the juvenile eel in the Fogliano lagoon, a typical Mediterranean coastal lake. The modelling approach has therefore proved to be a useful tool for predicting habitats for eel recruitment at the local scale and settlement, because

  6. Evaluation of some heavy metal loading in the Kpeshi lagoon, Ghana

    NASA Astrophysics Data System (ADS)

    Fianko, Joseph R.; Laar, Cynthia; Osei, Juilet; Anim, Alfred K.; Gibrilla, Abass; Adomako, Dickson

    2013-03-01

    A study was carried out on the Kpeshi lagoon to evaluate the relative contributions of some heavy metals (Na, k, Ca, K, Fe, Mn, Ni, Cr, Cd, Al, Pb) on the current state of the Kpeshi lagoon. The lagoon water was sampled along with some fish samples. Water pH, electrical conductivity and total dissolved salts were measured in situ whilst Na and K were measured using flame emission spectrometry. Heavy metals (iron, manganese, nickel, aluminium, chromium, lead and cadmium) in both water and fish samples were analyzed using atomic absorption spectrometry. Measured pH values ranged between 6.60 and 7.87, a mean conductivity and total dissolved salts of 87.31 ± 19.14 μS/cm and 38.4 ± 8.43 mg/L, respectively. Nutrient and organic matter were among the frequent source of pollution in the lagoon with mean sulphate, phosphate and nitrate concentrations of 190 ± 108.84, 1.62 ± 0.49 and 0.89 ± 0.26 mg/L, respectively. Iron and aluminium in the lagoon water measured the highest concentration of 13.2 ± 3.47 and 13.6 ± 4.29 mg/L, respectively. Fish samples however revealed very high concentrations of calcium and potassium measuring 15,709 ± 75.35 and 5,949.49 ± 87.30 mg/kg, respectively. Sodium and aluminium also revealed relatively high concentrations: 3,775.70 ± 24.80 and 708.47 ± 4.95 mg/kg, respectively. Notably, sites closer to settlement community (Teshie Township, e.g. S1, S2, S3 and S4) and the hospitality industries (i.e. dotted hotels, e.g. S7) appeared to be relatively more contaminated.

  7. Tidal dynamics of the Terminos Lagoon, Mexico: observations and 3D numerical modelling

    NASA Astrophysics Data System (ADS)

    Contreras Ruiz Esparza, Adolfo; Douillet, Pascal; Zavala-Hidalgo, Jorge

    2014-09-01

    The tidal circulation patterns in the Terminos Lagoon were studied based on the analysis of 1 year of measurements and numerical simulations using a baroclinic 3D hydrodynamic model, the MARS3D. A gauging network was installed consisting of six self-recording pressure-temperature sensors, a tide gauge station and two current profilers, with pressure and temperature sensors moored in the main lagoon inlets. Model simulations were validated against current and sea level observations and were used to analyse the circulation patterns caused by the tidal forcing. The numerical model was forced with eight harmonic components, four diurnal ( K 1, O 1, P 1, Q 1) and four semi-diurnal ( M 2, S 2, N 2, K 2), extracted from the TPX0.7 database. The tidal patterns in the study area vary from mixed, mainly diurnal in the two main inlets of the lagoon, to diurnal in its interior. The tidal residual circulation inside the lagoon is dominated by a cyclonic gyre. The results indicate a net flux from the southwest Ciudad del Carmen inlet (CdC) towards the northeast Puerto Real inlet (PtR) along the southern side of the lagoon and the opposite in the northern side. The results indicate two areas of strong currents in the vicinity of the inlets and weak currents inside the lagoon. The area of strong currents in the vicinity of the CdC inlet is larger than that observed in the PtR inlet. Nevertheless, the current analysis indicates that the highest current speeds, which can reach a magnitude of 1.9 m s-1, occurred in PtR. A further analysis of the tide distortion in the inlets revealed that both passages are ebb dominated.

  8. Biotic variation in coastal water bodies in Sussex, England: Implications for saline lagoons

    NASA Astrophysics Data System (ADS)

    Joyce, Chris B.; Vina-Herbon, Cristina; Metcalfe, Daniel J.

    2005-12-01

    Coastal water bodies are a heterogeneous resource typified by high spatial and temporal variability and threatened by anthropogenic impacts. This includes saline lagoons, which support a specialist biota and are a priority habitat for nature conservation. This paper describes the biotic variation in coastal water bodies in Sussex, England, in order to characterise the distinctiveness of the saline lagoon community and elucidate environmental factors that determine its distribution. Twenty-eight coastal water bodies were surveyed for their aquatic flora and invertebrate fauna and a suite of exploratory environmental variables compiled. Ordination and cluster analyses were used to examine patterns in community composition and relate these to environmental parameters. Biotic variation in the coastal water body resource was high. Salinity was the main environmental parameter explaining the regional distribution of taxa; freshwater and saline assemblages were evident and related to sea water ingress. Freshwater sites were indicated by the plant Myriophyllum spicatum and gastropod mollusc Lymnaea peregra, while more saline communities supported marine and brackish water taxa, notably a range of chlorophytic algae and the bivalve mollusc Cerastoderma glaucum. Site community differences were also related to bank slope and parameters describing habitat heterogeneity. A saline lagoon community was discerned within the matrix of biotic variation consisting of specialist lagoonal species with associated typically euryhaline taxa. For fauna, the latter were the molluscs Abra tenuis and Hydrobia ulvae, and the crustaceans Corophium volutator and Palaemonetes varians, and for flora they were the algae Ulva lactuca, Chaetomorpha mediterranea, Cladophora spp. and Enteromorpha intestinalis. One non-native polychaete species, Ficopomatus enigmaticus, also strongly influenced community structure within the lagoonal resource. The community was not well defined as specialist and

  9. Organic matter composition in the sediment of three Brazilian coastal lagoons: district of Macaé, Rio de Janeiro (Brazil).

    PubMed

    Zink, Klaus-Gerhard; Furtado, André L S; Casper, Peter; Schwark, Lorenz

    2004-03-01

    Freshwater lagoons comprise important coastal ecosystems and natural buffers between urbanized land areas and open ocean in the Rio de Janeiro State, Brazil. Studies of sediment and water chemistry, zooplankton and bacterial communities to assess the extent of anthropogenic disturbance are available. Here we contribute with an organic-geochemical approach supplemented by some microbiological aspects to complete the characterization of these lagoonal ecosystems. Bulk organic matter and extractable lipids (aliphatic hydrocarbons, alcohols and fatty acids, sterols) were investigated from two locations per lagoon: at the seaward site and landward ends - and at two depth intervals (0-3 and 3-6 cm) per site. Urbanized Imboacica Lagoon received increased anthropogenic input over the most recent years represented by the topmost 3 cm of sediment, whereas deeper sediment layers are less affected by human influence. Eutrophication or nutrient availability favored enhanced algal/cyanobacterial growth. In remote Cabiúnas and Comprida Lagoons pristine conditions are preserved. Organic matter from vascular plants dominates (chain length of free lipids up to C36), which is exceptionally well preserved by acidic lagoonal waters. Differentiation between landward and seaward sites in these two lagoons is less well established due to much smaller surface/volume to catchment ratios. No anthropogenic influences are yet detectable in sediments of Cabiúnas and Comprida Lagoons.

  10. Metal pollution loading, Manzalah lagoon, Nile delta, Egypt: Implications for aquaculture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Siegel, F.R.; Slaboda, M.L.; Stanley, D.J.

    1994-03-01

    High cultural enrichment factors are found for Hg (13 x), Pb (22.1 x), and other potentially toxic metals (e.g., Sn, Zn, Cu, Ag) in the upper 20 cm of sediment cores from the southeastern Ginka subbasin of Manzalah lagoon, Nile delta, Egypt. Cores from other areas of the lagoon show little metal loading. Metal loading followed the closure of the Aswan High Dam, the availability of abundant cheap electricity, and the development of major power-based industries. Industrial wastes containing potentially toxic metals are dumped into the Nile delta drain system. The load carried by Bahr El-Baqar drain discharges into themore » Ginka subbasin, which acts as a sink and results in metal loading of the sediment deposited there. Further development of aquaculture in this subbasin, of food-stuff agriculture on recently reclaimed lagoon bottom, or where irrigation waters come from Bahr El-Baqar drain or its discharge should be halted or strictly limited until potentially toxic metals in the drain waters and sediment are removed and polluted input drastically reduced. This environmental assessment of heavy metals in aquaculture or agriculture development should extend to other waterbodies in the northern Nile delta, particularly Idku lagoon and Lake Mariut, where industrial metal-bearing wastes discharge into the waterbodies. 21 refs., 7 figs., 3 tabs.« less

  11. Distribution and sources of carbon, nitrogen, phosphorus and biogenic silica in the sediments of Chilika lagoon

    NASA Astrophysics Data System (ADS)

    Nazneen, Sadaf; Raju, N. Janardhana

    2017-02-01

    The present study investigated the spatial and vertical distribution of organic carbon (OC), total nitrogen (TN), total phosphorus (TP) and biogenic silica (BSi) in the sedimentary environments of Asia's largest brackish water lagoon. Surface and core sediments were collected from various locations of the Chilika lagoon and were analysed for grain-size distribution and major elements in order to understand their distribution and sources. Sand is the dominant fraction followed by silt + clay. Primary production within the lagoon, terrestrial input from river discharge and anthropogenic activities in the vicinity of the lagoon control the distribution of OC, TN, TP and BSi in the surface as well as in the core sediments. Low C/N ratios in the surface sediments (3.49-3.41) and cores (4-11.86) suggest that phytoplankton and macroalgae may be major contributors of organic matter (OM) in the lagoon. BSi is mainly associated with the mud fraction. Core C5 from Balugaon region shows the highest concentration of OC ranging from 0.58-2.34%, especially in the upper 30 cm, due to direct discharge of large amounts of untreated sewage into the lagoon. The study highlights that Chilika is a dynamic ecosystem with a large contribution of OM by autochthonous sources with some input from anthropogenic sources as well.

  12. Lacaziosis in bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon, Florida, USA.

    PubMed

    Durden, Wendy Noke; St Leger, Judy; Stolen, Megan; Mazza, Teresa; Londono, Catalina

    2009-07-01

    The objective of this study was to document the presence of the fungal granulomatous skin disease lacaziosis in stranded Indian River Lagoon (IRL) bottlenose dolphins (Tursiops truncatus). From 1 January 2007 through 31 December 2007, stranded dolphins from the northern part of the IRL were thoroughly examined, and appropriate tissue samples were collected. The intralesional fungal agent (Lacazia loboi) was identified histologically in three bottlenose dolphins. Histologically, lacaziosis has been previously documented in IRL dolphins inhabiting the southern portion of the lagoon. Our findings suggest that the disease occurs throughout the lagoon. Enhanced monitoring of the prevalence of lacaziosis in dolphins throughout the IRL is needed to assess changes in population health.

  13. Biomonitoring approach with mussel Mytilus galloprovincialis (Lmk) and clam Ruditapes philippinarum (Adams and Reeve, 1850) in the Lagoon of Venice.

    PubMed

    Moschino, Vanessa; Delaney, Eugenia; Meneghetti, Francesca; Ros, Luisa Da

    2011-06-01

    Transplanted Mytilus galloprovincialis and native Ruditapes philippinarum were deployed in 10 sampling stations with different pollution impact within the Lagoon of Venice to evaluate the temporal variations and the suitability of the following cytochemical and histochemical biomarkers just as indicators of environmental stress: lysosomal membrane stability, lipofuscins, neutral lipids and lysosome to cytoplasm volume ratio. The physiological status of the organisms was also investigated by determining the survival in air capability and the reburrowing rate (clams). The biological parameters were assessed in June and October. Furthermore, for a better definition of the environmental aspects of the study sites, heavy metal, PAH and PCB concentrations were also evaluated in the sediments. As a whole, the biological responses examined in both species from all the sampling sites showed significant differences between the two seasonal campaigns, only lysosomal membrane stability exhibited less variability. Pollutants in sediments generally showed low-intermediate contamination levels, few hotspots persisting mostly in the inner areas of the lagoon, the most influenced by the industrial zone. Transplanted mussels were more responsive than native clams and the biological responses of both species varied temporally. The range of the spatial variability was always narrow and reflected only partially the broader variability shown by the chemical content in the sediments. In this sense, biological responses seemed to be particularly influenced by the high temporal and spatial heterogeneity that characterise the Lagoon of Venice, as well as most of the transitional environments.

  14. The Defense Committees of Sleepy Lagoon: A Convergent Struggle against Fascism, 1942-1944

    ERIC Educational Resources Information Center

    Barajas, Frank P.

    2006-01-01

    The Sleepy Lagoon Defense Committee originated as an ad hoc committee and evolved to a broad-based movement for legal justice on behalf of seventeen youth convicted of murder and assault charges in connection with the Sleepy Lagoon case in Los Angeles in January 1943. This essay chronicles the multidimensional organizing to shift public opinion in…

  15. [Mangrove dynamics in the Cispata lagoon system (Colombian Caribbean) during last 900 years].

    PubMed

    Castaño, Ana; Urrego, Ligia; Bernal, Gladys

    2010-12-01

    The lagoon complex of Cispatá (old Sinú river delta) located at the Northwestern coast of the Colombian Caribbean, encloses one of the biggest mangrove areas in this region. This area has changed during the last 330 years because of several environmental and climatic causes, mainly changes in the position of the delta (Sinú River), which is the main freshwater source in this area, and sea level rise. We hypothesized that the climatic and geomorphologic dynamics has caused changes in the extension and composition of mangrove vegetation, especially during last 150 years. The dynamics of mangroves during the last 900 years was reconstructed based on the changes in the stratigraphy, pollen record, calcite concentrations (CaCO3) and C/N ratio, along two sediment cores from La Flotante and Navio lagoons, located in Cispatá complex. The age model was built based on lineal interpolation of 210Pb ages and changes in granulometry. Establishment and expansion of mangrove forests during the last 900 years were related to fluviomarine dynamics in the area and the lagoon formation. During the period encompassed between 1064 and 1762 A.D., the Mestizos spit was formed when marine conditions predominated in the surroundings of La Flotante Lagoon. At the site of Navío, a river dominated lagoon, terrigenous conditions dominated since 1830. Although the colonization of herbaceous pioneer vegetation started between 1142 and 1331 A.D., mangrove colonization only took place since 1717 A.D. Mangrove colonization was a result of the delta progradation. In 1849 A.D. the Sinú river delta migrated to the Cispatá bay. The eustatic sea level rise, the increase in river discharges and sedimentation rates produced the establishment of mangrove forests dominated by Rhizophora since 1849. Since 1900 a marine intrusion was recorded in both lagoons. In 1938, the migration of the delta toward its actual location in Tinajones gave place to the formation of the present lagoon system and to the

  16. A new sampler for stratified lagoon chemical and microbiological assessments.

    PubMed

    McLaughlin, M R; Brooks, J P; Adeli, A

    2014-07-01

    A sampler was needed for a spatial and temporal study of microbial and chemical stratification in a large swine manure lagoon that was known to contain zoonotic bacteria. Conventional samplers were limited to collections of surface water samples near the bank or required a manned boat. A new sampler was developed to allow simultaneous collection of multiple samples at different depths, up to 2.3 m, without a manned boat. The sampler was tethered for stability, used remote control (RC) for sample collection, and accommodated rapid replacement of sterile tubing modules and sample containers. The sampler comprised a PVC pontoon with acrylic deck and watertight enclosures, for a 12 VDC gearmotor, to operate the collection module, and vacuum system, to draw samples into reusable autoclavable tubing and 250-mL bottles. Although designed primarily for water samples, the sampler was easily modified to collect sludge. The sampler held a stable position during deployment, created minimal disturbance in the water column, and was readily cleaned and sanitized for transport. The sampler was field tested initially in a shallow fresh water lake and subsequently in a swine manure treatment lagoon. Analyses of water samples from the lagoon tests showed that chemical and bacterial levels, pH, and EC did not differ between 0.04, 0.47, and 1.0 m depths, but some chemical and bacterial levels differed between winter and spring collections. These results demonstrated the utility of the sampler and suggested that future manure lagoon studies employ fewer or different depths and more sampling dates.

  17. Water hyacinths for upgrading sewage lagoons to meet advanced wastewater treatment standards, part 2

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.

    1976-01-01

    Field tests using water hyacinths as biological filtration agents were conducted in the Mississippi gulf coast region. The plants were installed in one single cell and one multiple cell sewage lagoon systems. Water hyacinths demonstrated the ability to maintain BOD5 and total suspended solid (TSS) levels within the Environmental Protection Agency's prescribed limits of 30 mg/lBOD5 and 30 mg/l TSS. A multiple cell sewage lagoon system consisting of two aerated and one water hyacinth covered cell connected in series demonstrated the ability to maintain BOD5 and TSS levels below 30 mg/l year-round. A water hyacinth covered lagoon with a surface area of 0.28 hectare containing a total volume of 6.8 million liters demonstrated the capacity to treat 437,000 to 1,893,000 liters of sewage influent from 2.65 hectares of aerated lagoons daily and produce an effluent that met or exceeded standards year-round.

  18. Calibration of Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon

    DTIC Science & Technology

    2016-07-01

    was used to drive the transport and water quality kinetics for the simulation of 2007–2009. The sand berm, which controlled the opening/closure of...TECHNICAL REPORT 3015 July 2016 Calibration of Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon Final Report Pei...Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon Final Report Pei-Fang Wang Chuck Katz Ripan Barua SSC Pacific James

  19. Characterization of a Mud Deposit Offshore of the Patos Lagoon, Southern Brazil

    DTIC Science & Technology

    2009-02-01

    Journal Article 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Characterization of mud deposit offshore of the Patos lagoon, southern Brazil 5a...deposition of mud on the beach along the shoreface of Rio Grande do Sul, Brazil dramatically influences the normal operations in the littoral zone...Continental Shelf Research journal homepage: www.elsevier.com/locate/csr Characterization of a mud deposit offshore of the Patos Lagoon, southern Brazil

  20. Growth, Survival and Reproduction of the Giant Clam Tridacna maxima (Röding 1798, Bivalvia) in Two Contrasting Lagoons in French Polynesia

    PubMed Central

    Van Wynsberge, Simon; Andréfouët, Serge; Gaertner-Mazouni, Nabila; Wabnitz, Colette C. C.; Menoud, Mathilde; Le Moullac, Gilles; Levy, Peva; Gilbert, Antoine; Remoissenet, Georges

    2017-01-01

    Shell growth, reproduction, and natural mortality of the giant clam Tridacna maxima were characterized over a two-year-period in the lagoon of the high island of Tubuai (Austral Archipelago) and in the semi-closed lagoon of Tatakoto (Tuamotu Archipelago) in French Polynesia. We also recorded temperature, water level, tidal slope, tidal range, and mean wave height in both lagoons. Lower lagoon aperture and exposure to oceanic swells at Tatakoto than at Tubuai was responsible for lower lagoon water renewal, as well as higher variability in temperature and water level at Tatakoto across the studied period. These different environmental conditions had an impact on giant clams. Firstly, spawning events in the lagoon of Tatakoto, detected by gonad maturity indices in June and July 2014, were timed with high oceanic water inflow and a decrease in lagoon water temperature. Secondly, temperature explained differences in shell growth rates between seasons and lagoons, generating different growth curves for the two sites. Thirdly, local mortality rates were also found to likely be related to water renewal patterns. In conclusion, our study suggests that reef aperture and lagoon water renewal rates play an integral role in giant clam life history, with significant differences in rates of shell growth, mortality and fertility found between open versus semi-closed atoll lagoons in coral reef ecosystems. PMID:28118406

  1. Mud deposit formation on the open coast of the larger Patos Lagoon-Cassino Beach system

    NASA Astrophysics Data System (ADS)

    Vinzon, S. B.; Winterwerp, J. C.; Nogueira, R.; de Boer, G. J.

    2009-03-01

    This paper proposes an explanation of the mud deposits on the inner Shelf of Cassino Beach, South Brazil, by using computational modeling. These mud deposits are mainly formed by sediments delivered from Patos Lagoon, a coastal lagoon connected to the Shelf, next to Cassino Beach. The deposits are characterized by (soft) mud layers of about 1 m thick and are found between the -5 and -20 isobaths. Two hydrodynamic models of the larger Patos Lagoon-Cassino Beach system were calibrated against water elevation measured for a 5 months period, and against currents and salinity measured for a week period. The circulation patterns and water exchange through the mouth were analyzed as a function of local and remote wind effects, and river discharges. The remote wind effect mainly governs the quantity of water exchange with the Lagoon through its effect on mean sea level as a result of Ekman dynamics, while river discharges are important for the salinity of the exchanged water masses. Local winds augment the export-import rates by set-up and set-down within the Lagoon, but their effects are much smaller than those of the remote wind. Currents patterns on the inner Shelf during water outflow revealed a recirculation zone south of the Lagoon, induced by the local geometry and bathymetry of the system. This recirculation zone coincides with observed locations of mud deposition. Water, hence suspended sediment export occurs when remote and local winds are from the N-E, which explains why fine sediment deposits are mainly found south of the Lagoon's breakwater. A sensitivity analysis with the numerical model quantified the contribution of the various mechanisms driving the transport and fate of the fine suspended sediments, i.e. the effects of remote and local wind, of the astronomical tide, of river discharge and fresh-salt water-induced density currents, and of earth rotation. It is concluded that gravitational circulation and earth rotation affects the further dispersion of

  2. Hydrologic characteristics of lagoons at San Juan, Puerto Rico, during an October 1974 tidal cycle

    USGS Publications Warehouse

    Gómez-Gómez, Fernando; Ellis, S.R.

    1983-01-01

    Flow and water-quality changes were studied during a period of intense rainfall in the San Juan Lagoon system. The study covered a 25-hour period beginning 0900 hours 22 October, 1974. Precipitation during the study period averaged 70 millimeters. Sampling stations were located at Boca de Cangrejos, the main ocean outlet; Canal Pinones between Laguna de Pinones and Laguna La Torrecilla; Canal Suarez between Laguna San Jose, connects to Laguna La Torrecilla; and Cano de Martin Pena between Laguna San Jose and Bahia de San Juan. In addition water-elevation recording gages were installed at each lagoon. Water samples from the canal stations were analyzed for organic carbon, nitrogen and phosphorus species, and suspended sediment. Specific-conductance measurements were used with the chemical data to estimate the runoff contributions of nutrients. Runoff into the lagoon, system during the study period was about 2.8 million cubic meters, or about 70 percent of the average precipitation. The runoff contributed chemical loadings to the lagoons of 95,000 kilograms total-organic carbon; 2,700 kilograms of total phosphorus; and 10,000 kilograms of total Khjeldhal nitrogen. A comparison with a prior study during which there was no significant rain, show that dry-period loadings are less than 10 percent of the wet-period loadings. At the end of the study period the system had not reached equilibrium, and the lagoons retained 80 percent of the water inflows from 50 to 90 percent of the chemical loads. Nearly 95 percent of the water outflows occurred at the Boca de Cangrejos sea outlet. The three lagoons and interconnecting canals form a very complex hydraulic system that is difficult to study using traditional techniques. A model of the system will facilitate management to improve the quality of water in the lagoons.

  3. Hydrological behavior of coastal lagoons associated to wetlands, an example from southernmost bahía Samborombón (Argentina).

    NASA Astrophysics Data System (ADS)

    Tejada Tejada, Macarena; Carol, Eleanora; Galliari, Julieta; Richiano, Sebastian

    2017-04-01

    Coastal wetlands are located at a critical interface between the terrestrial and marine environments and are ideally positioned to reduce impacts from land-based sources. At the southern region of Bahía Samborombón (Argentina) the wetlands includes several small coastal lagoons developed inside of a sandy spike. The main object of this work is to analyze the hydrological behavior of the lagoons evaluating their role in the maintenances of the wetland. In order to do this, satellite image analysis was performed to identify the marshy areas, drainage features, morphology and connections of the lagoons, both with the tidal flows from the Río de la Plata estuary and from the Argentine Sea. Field surveys were carried out in one of the lagoons to define their geological and geomorphological characteristics. After that, a monitoring network was designed for sampling the superficial and the underground water, additionally electrical conductivity and pH of the water were determined in situ. In all the water samples extracted the content of majority ions was determined by standard methods. Complementary, sedimentological and malacological aspects were observed at several stations in the lagoon. The obtained results allow us to recognize that the tidal flow that enters from the sea, at least in the studied lagoon, is the main hydrological sustenance of the wetland. This flow enters mainly using one tidal channel which connects (in a semi-permanent way) the sea with the lagoon during extraordinary tide and storm events. During low tide the lagoon loses connection and the drainage towards the sea is scarce. The tidal water that accumulates in the lagoon is subsequently evaporated causing an increase in the salinity of the surface water to values higher than the sea. Groundwater that accumulates through the infiltration of rainfall in the sandy sediments of the spike also discharges to the lagoon and supports the wetland surrounding the coastal lagoon. This flow, even when it

  4. Microcystins Presence in Mussels (M. galloprovincialis) and Water of Two Productive Mediterranean's Lagoons (Sardinia, Italy)

    PubMed Central

    Baralla, Elena; Varoni, Maria Vittoria; Sedda, Tiziana; Floris, Antonello; Demontis, Maria Piera

    2017-01-01

    Microcystins (MCs) are hepatotoxins harmful for animal and human health. The most toxic type between them is MC-LR whose presence has been investigated in different reservoirs all around the world. In this work microcystins were monitored in spring and summer in water and mussels (Mytilus galloprovincialis) of two Sardinia lagoons: Cabras and Calich lagoons. A Solid Phase Extraction method was developed to clean and concentrate samples before the Enzyme Linked Immunosorbent Assay (ELISA) and the following Mass Spectrometry detection. MCs presence was detected using the screening ELISA test in both lagoons. MCs peak was revealed in July for water and mussels belonging to Cabras lagoon (0.75 ± 0.07 ng/L in water and 0.12 ± 0.04 ng/g ww in mussels). In water of Calich lagoon there was a constant trend in the concentration of MCs during the considered months, while there was a MCs peak in July (0.6 ± 0.5 ng/g ww) in mussels. The following LC-MS/MS analysis did not reveal MC-LR presence in all analyzed samples. These results can be useful to enrich knowledge on public health and consumer's safeguard. PMID:29359150

  5. Water-Quality Monitoring and Biological Integrity Assessment in the Indian River Lagoon, Florida: Status, Trends, and Loadings (1988-1994).

    PubMed

    Sigua; Steward; Tweedale

    2000-02-01

    / The Indian River Lagoon (IRL) system that extends from Ponce DeLeon Inlet to Jupiter Inlet is comprised of three interconnected estuarine lagoons: the Mosquito Lagoon (ML), the Banana River Lagoon (BRL), and the Indian River Lagoon (subdivided into North Indian River Lagoon, NIRL and the South Indian River Lagoon, SIRL). The declines in both the areal coverage and species diversity of seagrass communities within the IRL system are believed to be due in part to continued degradation of water quality. Large inflows of phosphorus (P) and nitrogen (N) -laden storm-water from urban areas and agricultural land have been correlated with higher chlorophyll a production in the central, south central, and the south segments of the lagoon. In a system as large and complex as the lagoon, N and P limitations are potentially subject to significant spatial and temporal variability. Total Kjeldahl nitrogen (TN) was higher in the north (1.25 mg/liter) and lower in the south (0.89 mg/liter). The reverse pattern was observed for total P (TP), i.e., lowest in the north (0.03 mg/liter) and highest at the south (0.14 mg/liter) ends of the IRL. This increased P concentration in the SIRL appears to have a significantly large effect on chlorophyll a production compared with the other segments, as indicated by stepwise regression statistics. This relationship can be expressed as follows: South IRL [chlorophyll a] = -8.52 + 162.41 [orthophosphate] + 7.86 [total nitrogen] + 0.38 [turbidity]; R(2) = 0.98**.

  6. Tracing organic matter sources in a tropical lagoon of the Caribbean Sea

    NASA Astrophysics Data System (ADS)

    Alonso-Hernández, Carlos M.; Garcia-Moya, Alejandro; Tolosa, Imma; Diaz-Asencio, Misael; Corcho-Alvarado, Jose Antonio; Morera-Gomez, Yasser; Fanelli, Emanuela

    2017-09-01

    The natural protected lagoon of Guanaroca, located between Cienfuegos Bay and the Arimao River, Cuba, has been heavily impacted by human-induced environmental changes over the past century. Sources of organic matter in the Guanaroca lagoon and concentrations of radioisotopes (210Pb, 226Ra, 137Cs and 239,240Pu), as tracers of anthropogenic impacts, were investigated in a 78 cm sediment core. Variations in total organic carbon (TOC), total nitrogen (TN), stable isotopic composition (δ13C and δ15N) and ratio of total organic carbon to total nitrogen (C/N) were analysed. On such a basis, environmental changes in the lagoon were revealed. Down core variation patterns of the parameters representing sources of organic matter were predominantly related to the impacts of human activities. Up to the nineteenth century, the principal sources of organic matter to sediments (more than 80%) were a mixing of terrestrial vascular plants ( 48%) and freshwater phytoplankton ( 8%), with minimal contribution from the marine component ( 16%). In the period 1900-1980, due to the strong influence of human activities in the catchment area, the water exchange capacity of the lagoon declined substantially, as indicated by the relatively high proportion of organic matter originated from human activities (58%). Since 1980, as a result of management actions in the protected area, the lagoon has regained gradually its capability to exchange freshwater, showing sources of organic matter similar to the natural conditions recorded previous to 1900, although an indication of human impact (treated sewage contributed for 26% to the organic matter in sediments) was still observed and further management measures would be required.

  7. [Expanding the boundaries of clinics. Development of a community mental health program for children and teenagers from a rights perspective in the City of Buenos Aires].

    PubMed

    Barcala, Alejandra; Torricelli, Flavia

    2013-01-01

    There are forms of severe suffering in contemporary life that are not accommodated within the mechanisms offered by the mental health care system or that are not described on diagnostics handbooks, which need an appropriate response. This paper deals with the development of a community mental health program that provided care to children and teenagers with severe mental disorders and with a significant subjective suffering in the City of Buenos Aires from 2006 until the beginning of 2012. Pursuant to international standards in force in terms of mental health and human rights, this community, collective and territorial mental health practice suggested an inter-discipline and cross-sector approach that took into consideration the multi-dimension of social health determiners to provide comprehensive care. In order to offer a reply to fragmentation and the repeated traumas to which a large number of these children and teenagers have been exposed to, the program designed individual clinical-community strategies for each child or teenager, based on a network of continuous and reliable institutional supports. Conceived from a psychoanalytical approach, this praxis intended to benefit subjectification processes and the building of social bonds aiming at preventing the growing trends of administering medication and admitting children and teenagers as patients in mental health facilities.

  8. Assessing pollution in a Mediterranean lagoon using acid volatile sulfides and estimations of simultaneously extracted metals.

    PubMed

    Zaaboub, Noureddine; Helali, Mohamed Amine; Martins, Maria Virgínia Alves; Ennouri, Rym; Béjaoui, Béchir; da Silva, Eduardo Ferreira; El Bour, Monia; Aleya, Lotfi

    2016-11-01

    Bizerte Lagoon is a southern Mediterranean semi-enclosed lagoon with a maximum depth of 12 m. After assessing sediment quality, the authors report on the physicochemical characteristics of the lagoon's surface sediment using SEM (simultaneously extracted metals) and AVS (acid volatile sulfides) as proxies. Biogeochemical tools are used to investigate the environmental disturbance at the water-sediment interface by means of SEM and AVS to seek conclusions concerning the study area's pollution status. Results confirm accumulation of trace elements in sediment. The use of the SEM-AVS model with organic matter in sediment (ƒOC) confirms possible bioavailability of accumulated trace elements, especially Zn, in the southern part of the lagoon, with organic matter playing an important role in SEM excess correction to affirm a nontoxic total metal sediment state. Individual trace element toxicity is dependent on the bioavailable fraction of SEM Metal on sediment, as is the influence of lagoon inflow from southern water sources on element bioavailability. Appropriate management strategies are highly recommended to mitigate any potential harmful effects on health from this heavy-metal-based pollution.

  9. Recent sea-level changes and related engineering problems in the Lagoon of Venice (Italy)

    NASA Astrophysics Data System (ADS)

    Pirazzoli, Paolo Antonio

    In the city of Venice, where the average altitude is only a few tens of centimetres, there has been a dangerous increase in the frequency of flooding during the past few decades. Since 1872, the average increase in flooding levels (“acqua alta”) has been about 40cm: 27cm of this is due to the local rise in mean sea-level (of which some 14cm are related to man-induced subsidence of land, and 3-7cm to geological factors), and at least 14cm are caused by hydrodynamical factors, of which about 10cm can be ascribed to man-induced tidal changes. These latter are due above all to the dredging of deep artificial channels, the reclamation of wide areas of tidal flats, and the diking of fish ponds (“valli”), which have changed the ratio between the surface of the lagoon and that of the inlets. Since the latest modification (1963-1969), the lagoon has been open to large oil tankers, thereby allowing an easier entry of storm surges arising out at sea. Indeed an incompatibility exists between the accessibility of very large boats to the lagoon and the safeguard of Venice. Several engineering projects have been proposed with a view to improving the present critical situation. These projects include underground injections to raise the islands, the construction of new embankments, a reduction in the size of the passes, new access to wide areas for the tide, and the construction of flood gates at the passes. The reliability and effects of these projects are analysed and discussed. In conclusion, the removal of the oil terminal from the lagoon and a stricter control of water pollution are considered the most urgent preliminary actions for a long term solution of the flooding problem. This would enable a decrease in the exchanges between the lagoon and the sea, without, however, reducing the depth of the navigation channels to levels inconsistent with most of the present non-oil traffic. A final measure would be the construction of mobile gates at the passes which would

  10. Recovery of viruses from field samples of raw, digested, and lagoon-dried sludges*

    PubMed Central

    Sattar, Syed A.; Westwood, J. C. N.

    1979-01-01

    In a 22-month study, viruses were detected in 84% (62/74) of raw, 53% (19/36) of anaerobically digested, and 39% (11/28) of lagoon-dried sludge samples. Lagoon sludge contained detectable viruses (reovirus and enterovirus groups) even after 8 months of retention. Because of such prolonged virus survival in sludge, care must be taken in its disposal or utilization. PMID:311705

  11. Depositional history and fault-related studies, Bolinas Lagoon, California

    USGS Publications Warehouse

    Berquist, Joel R.

    1978-01-01

    Studies of core sediments and seismic reflection profiles elucidate the structure and depositional history of Bolinas Lagoon, Calif., which covers 4.4 km 2 and lies in the San Andreas fault zone at the southeast corner of the Point Reyes Peninsula 20 km northwest of San Francisco. The 1906 trace of the San Andreas fault crosses the west side of the lagoon and was determined from (1) tectonically caused salt-marsh destruction indicated by comparison of 1854 and 1929 U.S. Coast and Geodetic Survey (U.S.C. & G.S.) topographic surveys, (2) formation of a tidal channel along the border of destroyed salt marshes, and (3) azimuths of the trend of the fault measured in 1907. Subsidence in the lagoon of 30 cm occurred east of the San Andreas fault in 1906. Near the east shore, seismic-reflection profiling indicates the existence of a graben fault that may connect to a graben fault on the Golden Gate Platform. Comparison of radiocarbon dates on shells and plant debris from boreholes drilled on Stinson Beach spit with a relative sea-level curve constructed for southern San Francisco Bay indicates 5.8 to more than 17.9 m of tectonic subsidence of sediments now located 33 m below mean sea level. Cored sediments indicate a marine transgression dated at 7770?65 yrs B.P. overlying freshwater organic-rich lake deposits. Fossil pollen including 2 to 8 percent Picea (spruce) indicate a late Pleistocene (?)-Early Holocene climate, cooler, wetter, and foggier than at present. Above the transgression are discontinuous and interfingering sequences of transgressive-regressive marine, estuarine, and barrier sediments that reflect rapid lateral and vertical shifts of successive depositional environments. Fossil megafauna indicate (1) accumulation in a protected, shallow-water estuary or bay, and (2) that the lagoon was probably continuously shallow and never a deep-water embayment. Analysis of grain-size parameters, pollen frequencies, and organic remains from a core near the north end of

  12. A new model evaluating Holocene sediment dynamics: Insights from a mixed carbonate-siliciclastic lagoon (Bora Bora, Society Islands, French Polynesia, South Pacific)

    NASA Astrophysics Data System (ADS)

    Isaack, Anja; Gischler, Eberhard; Hudson, J. Harold; Anselmetti, Flavio S.; Lohner, Andreas; Vogel, Hendrik; Garbode, Eva; Camoin, Gilbert F.

    2016-08-01

    Mixed carbonate-siliciclastic lagoons of barrier reefs provide great potential as sedimentary archives focusing on paleoenvironmental and paleoclimatic changes as well as on event deposition. Sediment sources include lagoonal carbonate production, the marginal reef and the volcanic hinterland. Mixed carbonate-siliciclastic continent-attached coastal lagoons have been intensively studied, however, their isolated oceanic counterparts have been widely disregarded. Here, we present a new model of Holocene sediment dynamics in the barrier-reef lagoon of Bora Bora based on sedimentological, paleontological, geochronological and geochemical data. The lagoonal succession started with a Pleistocene soil representing the Lowstand Systems Tract. As the rising Holocene sea inundated the carbonate platform, peat accumulated locally 10,650-9400 years BP. Mixed carbonate-siliciclastic sedimentation started ca. 8700-5500 years BP and represents the Transgressive Systems Tract. During that time, sediments were characterized by relatively coarse grain size and contained high amounts of terrestrial material from the volcanic hinterland as well as carbonate sediments mainly produced within the lagoon. Siliciclastic content decreases throughout the Holocene. After the rising sea had reached its modern level, sand aprons formed between reef crest and lagoon creating transport pathways for reef-derived material leading to carbonate-dominated sedimentation ca. 6000-3000 years BP during the Highstand Systems Tract. However, mainly fine material was transported and accumulated in the lagoon while coarser grains were retained on the prograding sand apron. From ca. 4500-500 years BP, significant variations in grain-size, total organic carbon as indicator for primary productivity, Ca and Cl element intensities as qualitative indicators for carbonate availability and lagoonal salinity are seen. Such patterns could indicate event (re-)deposition and correlate with contemporaneous event deposits

  13. High human immunodeficiency virus type 1 seroprevalence in men who have sex with men in Buenos Aires, Argentina: risk factors for infection.

    PubMed

    Pando, Maria de los Angeles; Maulen, Sergio; Weissenbacher, Mercedes; Marone, Rubén; Duranti, Ricardo; Peralta, Liliana Martínez; Salomón, Horacio; Russell, Kevin; Negrete, Monica; Sosa Estani, Sergio; Montano, Silvia; Sanchez, José L; Avila, Maria Mercedes

    2003-10-01

    To determine human immunodeficiency virus (HIV) seroprevalence in a sample of men who have sex with men (MSM) in Buenos Aires City and to identify risk factors associated with HIV type 1 infection. Participants were invited to receive HIV counselling and testing at "NEXO" (a gay non-governmental organization) by means of informative leaflets distributed in gay nightclubs, porno cinemas, gymnasiums, and in the streets. During the encounter, the study was explained by a trained social worker and individuals were invited to volunteer for the study. Diagnosis of HIV was performed using two screening tests and Western Blot assay was used as confirmatory. Human immunodeficiency virus was detected in 96 (13.8%; 95% CI: 11.4-16.7) of 694 MSM. Fourteen (14.6%) of the 96 HIV-positive MSM were already aware of their HIV serostatus. In univariate analysis, HIV-1 infection (odds ratio [OR] >1.5) was found to be associated with older age (30-39 years), being unemployed, a previous sexually transmitted disease (STD) history, and having an HIV-positive partner. Cocaine consumption and irregular use of condoms with occasional partners were also found to be risk factors. In multivariate logistic regression analysis, being unemployed (OR = 3.42; 95% CI: 1.17-9.99) and having an HIV-positive partner (OR = 2.67; 95% CI: 1.09-6.52) remained significant risk factors. The high HIV-1 prevalence observed suggests an urgent need for implementation of effective prevention campaigns. This represents the first cross-sectional epidemiological study of HIV among the high-risk group of MSM in Argentina.

  14. Comprehensive assessment of hormones, phytoestrogens, and estrogenic activity in an anaerobic swine waste lagoon

    USGS Publications Warehouse

    Yost, Erin E.; Meyer, Michael T.; Dietze, Julie E.; Meissner, Benjamin M.; Williams, Mike; Worley-Davis, Lynn; Lee, Boknam; Kullman, Seth W.

    2013-01-01

    In this study, the distribution of steroid hormones, phytoestrogens, and estrogenic activity was thoroughly characterized within the anaerobic waste lagoon of a typical commercial swine sow operation. Three independent rounds of sampling were conducted in June 2009, April 2010, and February 2011. Thirty-seven analytes in lagoon slurry and sludge were assessed using LC/MS-MS, and yeast estrogen screen was used to determine estrogenic activity. Of the hormone analytes, steroidal estrogens were more abundant than androgens or progesterone, with estrone being the predominant estrogen species. Conjugated hormones were detected only at low levels. The isoflavone metabolite equol was by far the predominant phytoestrogen species, with daidzein, genistein, formononetin, and coumestrol present at lower levels. Phytoestrogens were often more abundant than steroidal estrogens, but contributed minimally towards total estrogenic activity. Analytes were significantly elevated in the solid phases of the lagoon; although low observed log KOC values suggest enhanced solubility in the aqueous phase, perhaps due to dissolved or colloidal organic carbon. The association with the solid phase, as well as recalcitrance of analytes to anaerobic degradation, results in a markedly elevated load of analytes and estrogenic activity within lagoon sludge. Overall, findings emphasize the importance of adsorption and transformation processes in governing the fate of these compounds in lagoon waste, which is ultimately used for broadcast application as a fertilizer.

  15. Comprehensive Assessment of Hormones, Phytoestrogens, and Estrogenic Activity in an Anaerobic Swine Waste Lagoon

    PubMed Central

    2013-01-01

    In this study, the distribution of steroid hormones, phytoestrogens, and estrogenic activity was thoroughly characterized within the anaerobic waste lagoon of a typical commercial swine sow operation. Three independent rounds of sampling were conducted in June 2009, April 2010, and February 2011. Thirty-seven analytes in lagoon slurry and sludge were assessed using LC/MS-MS, and yeast estrogen screen was used to determine estrogenic activity. Of the hormone analytes, steroidal estrogens were more abundant than androgens or progesterone, with estrone being the predominant estrogen species. Conjugated hormones were detected only at low levels. The isoflavone metabolite equol was by far the predominant phytoestrogen species, with daidzein, genistein, formononetin, and coumestrol present at lower levels. Phytoestrogens were often more abundant than steroidal estrogens, but contributed minimally toward total estrogenic activity. Analytes were significantly elevated in the solid phases of the lagoon; although low observed log KOC values suggest enhanced solubility in the aqueous phase, perhaps due to dissolved or colloidal organic carbon. The association with the solid phase, as well as recalcitrance of analytes to anaerobic degradation, results in a markedly elevated load of analytes and estrogenic activity within lagoon sludge. Overall, findings emphasize the importance of adsorption and transformation processes in governing the fate of these compounds in lagoon waste, which is ultimately used for broadcast application as a fertilizer. PMID:24144340

  16. Clipperton, a possible future for atoll lagoons

    NASA Astrophysics Data System (ADS)

    Charpy, L.; Rodier, M.; Couté, A.; Perrette-Gallet, C.; Bley-Loëz, C.

    2010-09-01

    Closure of the Clipperton Island atoll (10°17' N 109°13' W), now a meromictic lake, is estimated to have occurred between 1839 and 1849. It was still closed in 2005. Brackish waters in the upper layer (0-10 m) were oxygenated, while saline waters in the deep layer (>20 m) were anoxic. Allowing for the methodological difficulties of earlier measurements, the physical characteristics of the lagoon did not seem to have changed significantly since the last expedition (1980). The intermediate layer between brackish and saline waters was characterized by a strong density gradient and a temperature inversion of up to 1.6°C. Microbial activity, water exchange between the deep layer and surrounding oceanic waters and the geothermal flux hypothesis are discussed. The low DIN and SRP concentrations observed in the upper layer, despite high nutrient input by seabird droppings, reflect the high nutrient uptake by primary producers as attested by the elevated overall gross primary production (6.6 g C m-2 day-1), and high suspended photosynthetic biomass (2.23 ± 0.23 μg Chl a l-1) and production (263 ± 27 μg C l-1 day-1). Phytoplankton composition changed in 67 years with the advent of new taxa and the disappearance of previously recorded species. The freshwater phytoplanktonic community comprised 43 taxa: 37 newly identified during the expedition and 6 previously noted; 16 species previously found were not seen in 2005. The closure of the lagoon, combined with the positive precipitation-evaporation budget characteristic of the region, has induced drastic changes in lagoon functioning compared with other closed atolls.

  17. Social and environmental health determinants and their relationship with parasitic diseases in asymptomatic children from a shantytown in Buenos Aires, Argentina.

    PubMed

    Garbossa, Graciela; Pía Buyayisqui, María; Geffner, Laura; López Arias, Ludmila; de la Fournière, Sofía; Haedo, Ana S; Marconi, Adela E; Frid, Juan C; Nesse, Alcira B; Bordoni, Noemí

    2013-04-01

    Health inequities are a common problem for all countries and are the result of not only adverse social conditions but also poor public policies. Today chronic diseases represent the most relevant threats and are a current challenge. Parasitic infections, a leading cause of child morbidity affecting low-income populations, can be transmitted because of an unhealthy environment. Notwithstanding, scarce data have been published on the epidemiological profile of intestinal parasitoses in asymptomatic children living in shantytowns. Vulnerable populations settled in slums are growing in Argentina, particularly in Buenos Aires city. Consequently, this work intended to screen healthy carriers of enteric parasites and determine the epidemiologic profile in asymptomatic children residing in one of those communities, to explore risk factors associated with the transmission of parasites, and to initiate a basic health education campaign to promote healthy behavior in the community. Fecal samples (n = 138) were analyzed by conventional parasitological methods and a survey gathered data on symptoms, family composition, and environmental and hygiene-related variables. High prevalence of feco-orally-transmitted parasitoses (83·3%) and polyparasitism were remarkable findings. The main environmental health determinants were those related to excreta disposal and water provision. Health promotion actions were performed through the diffusion of a set of posters with iconic images and brief messages for health education. Results suggest the need for an environmental sanitation policy to complement health promotion actions. It is essential to spread the results of investigations that address inequities and social determinants of health in order to integrate data with local political processes and alert on acceptable actions for developing appropriate interventions.

  18. Social and environmental health determinants and their relationship with parasitic diseases in asymptomatic children from a shantytown in Buenos Aires, Argentina

    PubMed Central

    Garbossa, Graciela; Pía Buyayisqui, María; Geffner, Laura; López Arias, Ludmila; de la Fournière, Sofía; Haedo, Ana S; Marconi, Adela E; Frid, Juan C; Nesse, Alcira B; Bordoni, Noemí

    2013-01-01

    Health inequities are a common problem for all countries and are the result of not only adverse social conditions but also poor public policies. Today chronic diseases represent the most relevant threats and are a current challenge. Parasitic infections, a leading cause of child morbidity affecting low-income populations, can be transmitted because of an unhealthy environment. Notwithstanding, scarce data have been published on the epidemiological profile of intestinal parasitoses in asymptomatic children living in shantytowns. Vulnerable populations settled in slums are growing in Argentina, particularly in Buenos Aires city. Consequently, this work intended to screen healthy carriers of enteric parasites and determine the epidemiologic profile in asymptomatic children residing in one of those communities, to explore risk factors associated with the transmission of parasites, and to initiate a basic health education campaign to promote healthy behavior in the community. Fecal samples (n = 138) were analyzed by conventional parasitological methods and a survey gathered data on symptoms, family composition, and environmental and hygiene-related variables. High prevalence of feco-orally-transmitted parasitoses (83.3%) and polyparasitism were remarkable findings. The main environmental health determinants were those related to excreta disposal and water provision. Health promotion actions were performed through the diffusion of a set of posters with iconic images and brief messages for health education. Results suggest the need for an environmental sanitation policy to complement health promotion actions. It is essential to spread the results of investigations that address inequities and social determinants of health in order to integrate data with local political processes and alert on acceptable actions for developing appropriate interventions. PMID:23683369

  19. Dissolved Copper, Nickel and Lead in Tampamachoco Lagoon and Tuxpan River Estuary in the SW Gulf of Mexico.

    PubMed

    Garduño Ruiz, E P; Rosales Hoz, L; Carranza Edwards, A

    2016-10-01

    In order to estimate the effects of a thermal power plant, physicochemical parameters and the concentrations of copper, nickel and lead were evaluated in water from both Tampamachoco Lagoon and the estuary of the Tuxpan River. Average salinities were 33.66 ups in the lagoon area, 32.77 ups in the channel that joins the lagoon and the river, and 24.74 ups in the river estuary. Total average metal concentrations were 21.95 for Cu, 29.67 for Ni and 4.31 µ/L for Pb. Sampling point 1 and samples from the bottom water of the lagoon present the highest salinities and concentrations of suspended matter, TOC, Cu, Ni and Pb.These high values may be associated with the infiltration of sea water either from plant operation or from the channel that connects the lagoon with the sea.

  20. Identifying tsunami deposits using shell taphonomy: Sur lagoon, Oman

    NASA Astrophysics Data System (ADS)

    Donato, S.; Reinhardt, E.; Rothaus, R.; Boyce, J.

    2007-05-01

    On November 28th, 1945 an 8.1 magnitude earthquake focused in the eastern portion of the Makran subduction zone (Arabian Sea) generated a powerful tsunami that destroyed many coastal villages in Pakistan and India. Reports indicate that the tsunami also caused significant damage in Muscat, Oman, although its effects elsewhere in Oman are unknown. A thick bivalve dominated shell horizon was discovered inside the Sur lagoon, which is located on the eastern promontory of Oman (200 km south of Muscat). This shell deposit is significant because it is laterally extensive (> 1 km2), extends deep within the lagoon (>2 km), ranges in thickness from 5 - 25 cm at the sample localities, contains numerous subtidal and offshore bivalve species, and articulated subtidal and offshore bivalve species are abundant. Although there is an absence of typical tsunami indicators such as allochthonous sediment in and around the lagoon, verbal accounts, cultural evidence recovered during coring, and the absence of strong storms during the past 100 years indicates that this shell unit was caused by the 1945 tsunami. In this setting, it would be advantageous to have another proxy for tsunami detection and risk prediction. The use of shell taphonomy is one of the potential indicators and here we present new evidence of its utility. We sampled this unit in eight locations, and compared the shell taphonomy to surface shell samples collected from beach and reworked horizons in the lagoon, and to shell samples from a known tsunami and corresponding storm/ballast deposit in Israel (Reinhardt et al., 2006). Taphonomic analysis yielded promising results, as the two tsunami horizons shared excellent agreement between the amount of fragmented shells, and the percentage of shells displaying angular breaks. Both of these categories were significantly different from the percentage of fragments and angular fragments recovered from the reworked, beach, and storm/ballast deposits, indicating different

  1. Benthic foraminiferal and organic matter compounds as proxies of environmental quality in a tropical coastal lagoon: The Itaipu lagoon (Brazil).

    PubMed

    Raposo, Débora; Clemente, Iara; Figueiredo, Marcos; Vilar, Amanda; Lorini, Maria Lucia; Frontalini, Fabrizio; Martins, Virgínia; Belart, Pierre; Fontana, Luiz; Habib, Renan; Laut, Lazaro

    2018-04-01

    Lagoons in the southeast coast of Brazil have experienced eutrophication due to the exponential increase of human population and sewage discharges. Living benthic foraminifera have demonstrated to be good bioindicators of such impacts. This study aims to evaluate the organic matter accumulation effects on the foraminiferal distribution in the Itaipu lagoon (Brazil). On the basis of the biotic and abiotic analyses, three sectors are identified. The Sector I, an inner area, is characterized by high dissolved oxygen values and foraminiferal species with preference for marine conditions, demonstrating the sea influence. The Sector II, in the mangrove margins, is associated to sandy sediment and biopolymers and mainly represented by euryhaline species. The Sector III is marked by low density or absence of living foraminifera and corresponds to a low quality organic matter enriched area (North, Southwest and Centre). Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Liquid and atmospheric ammonia concentrations from a dairy lagoon during an aeration experiment

    NASA Astrophysics Data System (ADS)

    Rumburg, Brian; Neger, Manjit; Mount, George H.; Yonge, David; Filipy, Jenny; Swain, John; Kincaid, Ron; Johnson, Kristen

    Ammonia emissions from agriculture are an environmental and human health concern, and there is increasing pressure to reduce emissions. Animal agriculture is the largest global source of ammonia emissions and on a per cow basis dairy operations are the largest emitters. The storage and disposal of the dairy waste is one area where emissions can be reduced, aerobic biological treatment of wastewater being a common and effective way of reducing ammonia emissions. An aeration experiment in a dairy lagoon with two commercial aerators was performed for 1 month. Liquid concentrations of ammonia, total nitrogen, nitrite and nitrate were monitored before, during and after the experiment and atmospheric ammonia was measured downwind of the lagoon using a short-path differential optical absorption spectroscopy (DOAS) instrument with 1 ppbv sensitivity. No changes in either liquid or atmospheric ammonia concentrations were detected throughout the experiment, and neither dissolved oxygen, nitrite nor nitrate could be detected in the lagoon at any time. The average ammonia concentration at 10 sampling sites in the lagoon at a depth of 0.15 m was 650 mg l -1 and at 0.90 m it was 700 mg l -1 NH 3-N. The average atmospheric ammonia concentration 50 m downwind was about 300 ppbv. The 0.90 m depth total nitrogen concentrations and total and volatile solids concentrations decreased during the experiment due to some mixing of the lagoon but the 0.15 m depth concentrations did not decrease indicating that the aerators were not strong enough to mix the sludge off the bottom into the whole water column.

  3. State-of-the-lagoon reports as vehicles of cross-disciplinary integration.

    PubMed

    Zaucha, Jacek; Davoudi, Simin; Slob, Adriaan; Bouma, Geiske; van Meerkerk, Ingmar; Oen, Amy Mp; Breedveld, Gijs D

    2016-10-01

    An integrative approach across disciplines is needed for sustainable lagoon and estuary management as identified by integrated coastal zone management. The ARCH research project (Architecture and roadmap to manage multiple pressures on lagoons) has taken initial steps to overcome the boundaries between disciplines and focus on cross-disciplinary integration by addressing the driving forces, challenges, and problems at various case study sites. A model was developed as a boundary-spanning activity to produce joint knowledge and understanding. The backbone of the model is formed by the interaction between the natural and human systems, including economy and governance-based subsystems. The model was used to create state-of-the-lagoon reports for 10 case study sites (lagoons and estuarine coastal areas), with a geographical distribution covering all major seas surrounding Europe. The reports functioned as boundary objects to build joint knowledge. The experiences related to the framing of the model and its subsequent implementation at the case study sites have resulted in key recommendations on how to address the challenges of cross-disciplinary work required for the proper management of complex social-ecological systems such as lagoons, estuarine areas, and other land-sea regions. Cross-disciplinary integration is initially resource intensive and time consuming; one should set aside the required resources and invest efforts at the forefront. It is crucial to create engagement among the group of researchers by focusing on a joint, appealing overall concept that will stimulate cross-sectoral thinking and focusing on the identified problems as a link between collected evidence and future management needs. Different methods for collecting evidence should be applied including both quantitative (jointly agreed indicators) and qualitative (narratives) information. Cross-disciplinary integration is facilitated by functional boundary objects. Integration offers important

  4. Diazotroph community succession during the VAHINE mesocosms experiment (New Caledonia Lagoon)

    NASA Astrophysics Data System (ADS)

    Turk-Kubo, K. A.; Frank, I. E.; Hogan, M. E.; Desnues, A.; Bonnet, S.; Zehr, J. P.

    2015-06-01

    The VAHINE mesocosm experiment, conducted in the low-nutrient low-chlorophyll waters of the Noumea Lagoon (coastal New Caledonia) was designed to trace the incorporation of nitrogen (N) fixed by diazotrophs into the food web, using large volume (50 m3) mesocosms. This experiment provided a unique opportunity to study the succession of different N2-fixing microorganisms (diazotrophs) and calculate in situ net growth and loss rates in response to fertilization with dissolved inorganic phosphate (DIP) over a 23 day period, using quantitative polymerase chain reaction (qPCR) assays. Inside the mesocosms, the diazotroph community assemblage was dominated by the heterocyst-forming Richelia associated with Rhizosolenia (Het-1) in the first half of the experiment, and unicellularcyanobacterial Group C (UCYN-C) became the dominant diazotroph in the second half of the experiment. Decreasing DIP concentrations following the fertilization event and increasing temperatures were significantly correlated with increasing abundances of UCYN-C. Maximum net growth rates for UCYN-C were calculated to be between 1.23 ± 0.07 and 2.16 ± 0.07 d-1 which are among the highest growth rates reported for diazotrophs. Outside the mesocosms in the Noumea Lagoon, UCYN-C abundances remained low, despite increasing temperatures, suggesting that the microbial community response to the DIP fertilization created conditions favorable for UCYN-C growth inside the mesocosms. Maximum net growth and loss rates for nine diazotroph phylotypes throughout the 23 day experiment were variable between mesocosms, and repeated fluctuations between periods of net growth and loss were commonly observed. The field population of diazotrophs in the Noumea Lagoon, was dominated by Het-1 over the course of the study period. However, eight additional diazotroph phylotypes were present in the lagoon at lower abundances, indicating a diverse field population of diazotrophs. Two ecotypes of the Braarudosphaera bigelowii

  5. Macrobenthic molluscs from a marine - lagoonal environmental transition in Lesvos Island (Greece).

    PubMed

    Evagelopoulos, Athanasios; Koutsoubas, Drosos; Gerovasileiou, Vasilis; Katsiaras, Nikolaos

    2016-01-01

    This paper describes an occurence dataset, also including numerical abundance and biomass data, pertaining to the macrobenthic molluscan assemblages from a marine - lagoonal environmental transition. The study system was the soft-substrate benthoscape of the area of the Kalloni solar saltworks (Lesvos Island, Greece). Specifically, the study area extended from the infralittoral zone of the inner Kalloni Gulf (marine habitat) to the bottoms of the first two evaporation ponds of the Kalloni solar saltworks (lagoonal habitat). Bottom sediment samples (3 replicates) were collected with a Van Veen grab sampler (0.1 m 2 ) at four sampling sites, along a 1.5 km long line transect that spanned the marine - lagoonal environmental transition. A total of four surveys were carried out seasonally in 2004.  A total of 39,345 molluscan individuals were sorted out of the sediment samples and were identified to 71 species, belonging to the Gastropoda (36), Bivalvia (34) and Scaphopoda (1) classes. Numerical abundance and wet biomass (with shells) data are included in the dataset. The dataset described in the present paper partially fills a significant gap in the scientific literature: Because ecological research of coastal lagoons has seldom explicitly considered the marine - lagoonal habitats interface, there are no openly accessible datasets pertaining to the particular structural component of the transitional waters benthoscapes of the Mediterranean Sea. Such datasets could prove valuable in the research of the structure and functioning of transitional waters benthoscapes. The present dataset is available as a supplementary file (Suppl. material 1) and can also be accessed at http://ipt.medobis.eu/resource?r=kalloni_saltworks_phd.

  6. Identifying nutrient sources to three lagoons at Ofu and Olosega, American Samoa using δ15N of benthic macroalgae

    USGS Publications Warehouse

    Garrison, Virginia H.; Kroeger, Kevin D.; Fenner, Douglas; Craig, Peter

    2007-01-01

    Degradation of nearshore habitats is a serious problem in some areas of American Samoa, such as in Pago Pago Harbor on Tutuila Island, and is a smaller but chronic problem in other areas. Sedimentation, pollution, nutrient enrichment from surface runoff or groundwater, and trampling are the major factors causing the changes (Peshut and Brooks, 2005). On the outer islands of Ofu and Olosega (Manu’a Islands; Fig. 1), there is an interesting contrast between relatively pristine lagoon habitats not far from comparatively degraded lagoon habitats. To’aga lagoon on the southeast side of Ofu Island (Fig. 1) has clear waters, a high diversity of corals and fishes, no human habitations, and an undeveloped watershed with no streams. To’aga lagoon is within the boundaries of the National Park of American Samoa and is the site of long-term research on coral reef resilience and global climate change. Only 3 km to the east of To’aga is a degraded lagoon that fronts Olosega Village. The Olosega lagoon is similar in size but has significantly less live coral than To’aga, and blooms of filamentous algae have been reported to cover the Olosega lagoon/reef flat bottom (unpublished data, PC; Fig. 2). The islands are influenced by the same regional-scale and biogeochemical regimes, and both islands are remnants of a volcanic caldera (Craig, 2005). Thus, local factors operating on the scale of a kilometer or less are thought to be driving the differences observed between lagoons. Land disturbance is limited to a road linking the villages, the clearing of vegetation for buildings, and two village dump sites located on the narrow strip of land between the steep slopes of the islands and the shoreline; there is no industry or associated pollution on either island. Cesspools are used for sewage disposal. Nutrient enrichment (from cesspools) of groundwater and the lagoon, as well as trampling during gleaning of reef organisms, are possible factors affecting the spatial relief

  7. Methane in Sediments From Three Tropical, Coastal Lagoons on the Yucatan Peninsula, Mexico

    NASA Astrophysics Data System (ADS)

    Young, B.; Paytan, A.; Miller, L.; Herrera-Silveira, J.

    2002-12-01

    Tropical wetlands are significant sources of methane (CH4) to the atmosphere, and the majority of research on methane flux and cycling in the tropics has been conducted in fresh-water wetlands and lakes. However, several previous studies have shown that tropical coastal ecosystems can produce significant methane flux to the atmosphere despite the presence of moderate to marine salinities. Information regarding methane cycling within the sediments is crucial to understanding how natural and anthropogenic changes may influence these systems. We measured methane concentrations in sediments from two tropical coastal lagoons during different seasons, as well as in a third, heavily polluted, lagoon (Terminos) during the rainy season. These three lagoons, Celestun, Chelem, and Terminos, have similar vegetation, seasonal temperature and rainfall patterns, and substrate geology, but very different levels of ground water discharge and pollution. Methane concentrations in Celestun and Terminos lagoon showed high spatial variability(> 0.001 to 5 mmol kg-1 wet sediment), while sediments in Chelem Lagoon, which has near marine salinities and little sewage discharge, showed much lower variability of methane concentrations. Methane concentrations in Celestun sediments displayed two predominant patterns: some profiles contained a peak in methane concentration (1 to 2 mmole methane kg-1 wet sediment) between 5 and 15 cm below the surface while the other sediment profiles instead displayed a steady or monotonic increase in methane concentration with depth to approximately 0.025-0.080 mmol kg-1 at 10-15cm below surface followed by stable methane concentrations to the bottom of the cores (20-45 cm below the surface). A subsurface peak in methane concentrations was also found in some locations in Chelem, however, the concentrations were much lower than those measured in Celestun. Previous studies have shown that sewage pollution may drastically increase methane production in tropical

  8. Atoll-phosphate genesis: Role of lagoonal biomass and possible role of endo-upwelling processes in phosphate concentration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Trichet, J.; Rougerie, F.

    1990-06-01

    Sedimentological and hydrogeological data in Niau, a closed atoll in French Polynesia where P-concentration has been measured, suggest the role played by lagoonal organic matter in P-accumulation and the possible role of endo-upwelling processes in P-input in the system. A 15 m deep core through the lagoonal deposits shows the succession of organic-rich strata in which the P-content can reach up to 1.3% P{sub 2}O{sub 5}. Such a pattern suggests that, whatever the source of P within the lagoon (lagoonal water, bird guano, or endo-upwelled solutions, see below), this element is likely to be incorporated in quantitatively important lagoonal biomassmore » whose decay releases phosphorus back to the sediment. An example of such biomass and organic matter is given by the large amounts of cyano-bacterial organic matter that are present in the lagoon of Niau. A source for island phosphate has recently been proposed to be relatively deep seawater, which would be endo-upwelled from depths of hundreds of meters ({approximately}500 m, where P content is approximately 1.5 mmol.m{sup {minus}3} PO{sub 4}-P) through the permeable reef-body up to its surface (i.e., to its lagoonal waters, where P content reaches 5 mmol.m{sup {minus}3} in Niau atoll). The energy necessary for the transport of such solutions would be geothermal (at the bottom of the water column, i.e., close to the volcanic substrate of the reef body) and solar at its top through evaporation.« less

  9. Tet and sul antibiotic resistance genes in livestock lagoons of various operation type, configuration, and antibiotic occurrence

    USGS Publications Warehouse

    McKinney, C.W.; Loftin, K.A.; Meyer, M.T.; Davis, J.G.; Pruden, A.

    2010-01-01

    Although livestock operations are known to harbor elevated levels of antibiotic resistant bacteria, few studies have examined the potential of livestock waste lagoons to reduce antibiotic resistance genes (ARGs). The purpose of this study was to determine the prevalence and examine the behavior of tetracycline [tet(O) and tet(W)] and sulfonamide [sul(I) and su/(II)] ARGsin a broad cross-section of livestock lagoons within the same semiarid western watershed. ARGs were monitored for one year in the water and the settled solids of eight lagoon systems by quantitative polymerase chain reaction. In addition, antibiotic residues and various bulk water quality constituents were analyzed. It was found that the lagoons of the chicken layer operation had the lowest concentrations of both tet and sul ARGs and low total antibiotic concentrations, whereas su ARGs were highest in the swine lagoons, which generally corresponded to the highest total antibiotic concentrations. A marginal benefit of organic and small dairy operations also was observed compared to conventional and large dairies, respectively. In all lagoons, su ARGs were observed to be generally more recalcitrant than tet ARGs. Also, positive correlations of various bulk water quality constituents were identified with tet ARGs but not sul ARGs. Significant positive correlations were identified between several metals and tet ARGs, but Pearson's correlation coefficients were mostly lower than those determined between antibiotic residues and ARGs. This study represents a quantitative characterization of ARGs in lagoons across a variety of livestock operations and provides insight into potential options for managing antibiotic resistance emanating from agricultural activities. ?? 2010 American Chemical Society.

  10. Environmental changes in the Moulay Bousselham lagoon (Morocco) during the last 7 000 years using a multiproxy approach

    NASA Astrophysics Data System (ADS)

    Zourarah, Bendahhou; Maanan, Mohamed; Conceição Freitas, Maria; Leroy, Suzanne; Andrade, César; Cearreta, Alejandro; Cruces, Anabela

    2016-04-01

    The aim of this research is to reconstruct Holocene environmental changes in Moulay Bousselham lagoon using a multi-proxy approach to the study of sediments of two short cores: biological (e.g., pollen, foraminifera and diatoms), physicochemical (isotopes, chemical composition) and sedimentary (grain size, clay minerals). The research highlights the role of climatic variations and human interference in the evolution of this lagoon. The results show that at the beginning of the Holocene this area corresponded to a wide coastal bay, including the surface of Moulay Bousselham present-day lagoon and Merja Ras Ed-Dora. The dating's obtained in the base of the sediment cores range from 6790-6640 BP (end of the Atlantic and early Sub-boreal). Sand predominates in this section of the cores, with low content of organic matter and high content of bioclasts. Ammonia tepida is the predominant species but Haynesina germânica, Quinqueloculina semínula,Cibicides lobatulus,Criboelphidium oceanensis and Miliolinella sobrotunda are also presente. At the base, foraminifera assemblages show a relative abundance of Planorbulina mediterranensis, Rosalina anomala, Rosalina irregularis, Miliolinella subrotunda and Cibicides lobatulus. These are typical of a shallow environment with normal marine salinity. During the sub-boreal period (6640-4520 BP), a sandy barrier developed and the lagoon evolved to a brackish lagoon with low salinity. Sedimentation is homogeneous, the content of silt and clay is high (90%), calcium carbonate content is usually lower than 20% and the organic material exhibited the highest values (> 10%). Ammonia tepida is also the dominant species but C. oceanensis and H. germanica are secondary. The lagoon was closed in drier conditions and has gradually filled by sediments coming from the watershed, represented by an illite-chlorite association. The lagoon evolved to a sabkha. We must emphasize the role of deforestation caused by the Romans (2100 BP) in that period

  11. Alterations in macroinvertebrate spatial patterns in coastal lagoons: Óbidos (NW coast of Portugal) 1984 versus 2002

    NASA Astrophysics Data System (ADS)

    Rodrigues, Ana Maria; Quintino, Victor; Pereira, Fábio; Freitas, Rosa

    2012-09-01

    The macroinvertebrate spatial distribution patterns in the Lagoon of Óbidos were studied in 1984 and revisited in 2002. The overall surficial sediments and benthic community patterns show consistent similarities in the two sampling periods, but also important differences. The lagoon is relatively shallow, with about 1/3 of the area covered with extensive intertidal sand banks. These are interrupted by a navigation channel bordering the northern margin (1984) and, following dredging operations, a new navigation channel was opened along the southern margin (2002). The sediments in the navigation channels were coarser and with less percentage of fines in 2002 than in 1984. Arthropods dominated the species richness and abundance in 1984, but were much less important in 2002, when the community was dominated by molluscs and annelids, both in species numbers as well as in abundance. In 1984, the structure of the macrofauna communities closely followed a general model proposed for Atlantic and Mediterranean lagoons, with the marine, the transition and the lagoon communities occupying very well defined areas. This gradient was in accordance with an increase in the fines and organic matter content directed inwards allowing for the coexistence of several characteristic lagoon species with others characteristic of organic enriched sediments. In 2002 this spatial pattern is still recognized but the marine and the transition communities are spatially mixed, occupying both the entrance region and the navigation channels, whereas the characteristic lagoon community identified in 1984 was only recognized in a group of sites located along the southern margin in 2002. Several species show very important changes in their distribution extent in the lagoon system. These changes essentially show a generalized inward expansion of the distribution range of the marine species, in agreement with a larger influence of marine conditions toward the inner areas of the lagoon. This study shows

  12. The structure and productivity of the Thalassia testudinum community in Bon Accord Lagoon, Tobago.

    PubMed

    Juman, Rahanna A

    2005-05-01

    The Thalassia testudinum dominated seagrass community in the Buccoo Reef/ Bon Accord Lagoon Marine Park, measures 0.5 km(2) and is part of a contiguous coral reef, seagrass bed and mangrove swamp system in southwest Tobago. 7 testudinum coverage, productivity and percent turnover rates were measured from February 1998 to February 1999 at four sample locations, while total T. testudinum biomass was measured at two locations in the lagoon from 1992-2002. Productivity and turnover rates varied spatially and seasonally. They were higher in the back-reef area than in the mangrove-fringed lagoon, and were lowest at locations near to a sewage outfall. 7 testudinum coverage ranged from 6.6% in the lagoon to 68.5% in the back-reef area while productivity ranged from 3.9 to 4.9 g dry wt m(-2) d(-1) . Productivity and percentage turnover rates were higher in the dry season (January-June) than in the wet season (July-December). Productivity ranged from 3.0 in the wet season to 5.0 g dry wt m2 d-' in the dry season while percentage turnover rates ranged from 4.2% to 5.6%. Total Thalassia biomass and productivity in Bon Accord Lagoon were compared to six similar sites in the Caribbean that also participate in the Caribbean Coastal Marine Productivity Program (CARICOMP). This seagrass community is being negatively impacted by nutrient-enriched conditions.

  13. Modelling the salinization of a coastal lagoon-aquifer system

    NASA Astrophysics Data System (ADS)

    Colombani, N.; Mastrocicco, M.

    2017-08-01

    In this study, a coastal area constituted by alternations of saline-brackish lagoons and freshwater bodies was studied and modelled to understand the hydrological processes occurring between the lagoons, the groundwater system of the Po River Delta (Italy) and the Adriatic Sea. The contribution of both evaporation and anthropogenic factors on groundwater salinization was assessed by means of soil, groundwater and surface water monitoring. Highresolution multi-level samplers were used to capture salinity gradients within the aquifer and surface water bodies. Data were employed to calibrate a density-dependent numerical transport model implemented with SEAWAT code along a transect perpendicular to the coast line. The results show that the lagoon is hydraulically well connected with the aquifer, which provides the major source of salinity because of the upcoming of paleo-seawater from the aquitard laying at the base of the unconfined aquifer. On the contrary, the seawater (diluted by the freshwater river outflow) creates only a limited saltwater wedge. The increase in groundwater salinity could be of serious concern, especially for the pinewood located in the dune near the coast, sensitive to salinity increases. This case study represents an interesting paradigm for other similar environmental setting, where the assumption of classical aquifer salinization from a saltwater wedge intruding from the sea is often not representative of the actual aquifer’s salinization mechanisms.

  14. Wind effects on prey availability: How northward migrating waders use brackish and hypersaline lagoons in the sivash, Ukraine

    NASA Astrophysics Data System (ADS)

    Verkuil, Yvonne; Koolhaas, Anita; Van Der Winden, Jan

    Large numbers of waders migrating northward in spring use the Sivash, a large system of shallow, brackish and hypersaline lagoons in the Black Sea and Azov Sea region (Ukraine). The bottoms of these lagoons are often uncovered by the wind. Hence, for waders the time and space available for feeding depend on wind conditions. In hypersaline lagoons the benthic and pelagic fauna was very poor, consisting mainly of chironomid larvae (0.19 g AFDM·m -2) and brine shrimps Artemia salina, respectively. Brine shrimp abundance was correlated with salinity, wind force, wind direction and water depth. Dunlin Calidris alpina and curlew sandpiper Calidris ferruginea were the only species feeding on brine shrimp. As brine shrimp densities are higher in deeper water, smaller waders such as broad-billed sandpipers Limicola falcinellus are too short-legged to reach exploitable densities of brine shrimp. In brackish lagoons the benthic and pelagic fauna was rich, consisting of polychaetes, bivalves, gastropods, chironomid larvae, isopods and amphipods (8.9 to 30.5 g AFDM·m -2), but there were no brine shrimps. Prey biomass increased with the distance from the coast, being highest on the site that was most frequently inundated. Dunlin, broad-billed sandpiper and grey plover Pluvialis squatarola were the most abundant birds in the brackish lagoon. Due to the effects of wind-tides only a small area was usually available as a feeding site. Gammarus insensibilis was the alternative prey resource in the water layer, and their density varied with wind direction in the same way as brine shrimp. Curlew sandpipers and dunlins in the hypersaline lagoons and broad-billed sandpipers in the brackish lagoons often changed feeding sites, probably following the variation in prey availability. Only because of the large size and variety of lagoons are waders in the Sivash always able to find good feeding sites.

  15. Epidemiology of Toxocara canis in the dog population from two areas of different socioeconomic status, Greater Buenos Aires, Argentina.

    PubMed

    Rubel, D; Zunino, G; Santillán, G; Wisnivesky, C

    2003-07-29

    Toxocara canis infection in dogs is a public health problem in most countries, although it has been poorly documented in many of them. The main objective of the present work was to investigate the epidemiology of infection in the canine populations from two areas of Buenos Aires of different socioeconomic status and urban conditions: a middle-income neighbourhood (MIN) and a low-income neighbourhood (LIN). This study evaluated the prevalence of infection in dogs by parasitological and serological techniques in both areas, and described the relationship between the infection and different epidemiological variables for each neighbourhood. A cross-sectional study was carried out after a house-to-house census was completed. During August 1999, a sample of households was selected at random (nMIN=53 and nPA=52). In each house, one dog was randomly chosen for the collection of fresh faeces and blood. The dog owners were interviewed utilising a questionnaire about dogs on sex, recent anthelmintic treatment, degree of confinement, control by the dog's owner (whether the dog goes out of the house accompanied or not, leashed or unleashed), defecation site, defecation substratum and number of dogs in the house. The diagnostic techniques were concentration-sedimentation formalin/ether method and ELISA test. The parasitological prevalences in dogs were 9% (5/53) in MIN and 19% (10/52) in LIN, and serological prevalences were 22% (2/9) in MIN and 40% (15/37) in LIN. In MIN, the patent infection of males was significantly higher than that of females. In LIN, puppies less than 1 year old were the most prevalent age class. Our serological results showed that the positivity of adult dogs was more frequent in LIN than in MIN. The density of puppies with patent infection was seven times higher in LIN than in MIN, when combining coprological analysis and the estimated age structure obtained by the census.

  16. Potential changes in bacterial metabolism associated with increased water temperature and nutrient inputs in tropical humic lagoons.

    PubMed

    Scofield, Vinicius; Jacques, Saulo M S; Guimarães, Jean R D; Farjalla, Vinicius F

    2015-01-01

    Temperature and nutrient concentrations regulate aquatic bacterial metabolism. However, few studies have focused on the effect of the interaction between these factors on bacterial processes, and none have been performed in tropical aquatic ecosystems. We analyzed the main and interactive effects of changes in water temperature and N and P concentrations on bacterioplankton production (BP), bacterioplankton respiration (BR) and bacterial growth efficiency (BGE) in tropical coastal lagoons. We used a factorial design with three levels of water temperature (25, 30, and 35°C) and four levels of N and/or P additions (Control, N, P, and NP additions) in five tropical humic lagoons. When data for all lagoons were pooled together, a weak interaction was observed between the increase in water temperature and the addition of nutrients. Water temperature alone had the greatest impact on bacterial metabolism by increasing BR, decreasing BP, and decreasing BGE. An increase of 1°C lead to an increase of ~4% in BR, a decrease of ~0.9% in BP, and a decrease of ~4% in BGE. When data were analyzed separately, lagoons responded differently to nutrient additions depending on Dissolved Organic Carbon (DOC) concentration. Lagoons with lowest DOC concentrations showed the strongest responses to nutrient additions: BP increased in response to N, P, and their interaction, BR increased in response to N and the interaction between N and P, and BGE was negatively affected, mainly by the interaction between N and P additions. Lagoons with the highest DOC concentrations showed almost no significant relationship with nutrient additions. Taken together, these results show that different environmental drivers impact bacterial processes at different scales. Changes of bacterial metabolism related to the increase of water temperature are consistent between lagoons, therefore their consequences can be predicted at a regional scale, while the effect of nutrient inputs is specific to different

  17. Potential changes in bacterial metabolism associated with increased water temperature and nutrient inputs in tropical humic lagoons

    PubMed Central

    Scofield, Vinicius; Jacques, Saulo M. S.; Guimarães, Jean R. D.; Farjalla, Vinicius F.

    2015-01-01

    Temperature and nutrient concentrations regulate aquatic bacterial metabolism. However, few studies have focused on the effect of the interaction between these factors on bacterial processes, and none have been performed in tropical aquatic ecosystems. We analyzed the main and interactive effects of changes in water temperature and N and P concentrations on bacterioplankton production (BP), bacterioplankton respiration (BR) and bacterial growth efficiency (BGE) in tropical coastal lagoons. We used a factorial design with three levels of water temperature (25, 30, and 35°C) and four levels of N and/or P additions (Control, N, P, and NP additions) in five tropical humic lagoons. When data for all lagoons were pooled together, a weak interaction was observed between the increase in water temperature and the addition of nutrients. Water temperature alone had the greatest impact on bacterial metabolism by increasing BR, decreasing BP, and decreasing BGE. An increase of 1°C lead to an increase of ~4% in BR, a decrease of ~0.9% in BP, and a decrease of ~4% in BGE. When data were analyzed separately, lagoons responded differently to nutrient additions depending on Dissolved Organic Carbon (DOC) concentration. Lagoons with lowest DOC concentrations showed the strongest responses to nutrient additions: BP increased in response to N, P, and their interaction, BR increased in response to N and the interaction between N and P, and BGE was negatively affected, mainly by the interaction between N and P additions. Lagoons with the highest DOC concentrations showed almost no significant relationship with nutrient additions. Taken together, these results show that different environmental drivers impact bacterial processes at different scales. Changes of bacterial metabolism related to the increase of water temperature are consistent between lagoons, therefore their consequences can be predicted at a regional scale, while the effect of nutrient inputs is specific to different

  18. Diazotroph community succession during the VAHINE mesocosm experiment (New Caledonia lagoon)

    NASA Astrophysics Data System (ADS)

    Turk-Kubo, K. A.; Frank, I. E.; Hogan, M. E.; Desnues, A.; Bonnet, S.; Zehr, J. P.

    2015-12-01

    The VAHINE mesocosm experiment, conducted in the low-nutrient low-chlorophyll waters of the Noumea lagoon (coastal New Caledonia) was designed to trace the incorporation of nitrogen (N) fixed by diazotrophs into the food web, using large volume (50 m3) mesocosms. This experiment provided a unique opportunity to study the succession of different N2-fixing microorganisms (diazotrophs) and calculate in situ net growth and mortality rates in response to fertilization with dissolved inorganic phosphate (DIP) over a 23-day period, using quantitative polymerase chain reaction (qPCR) assays targeting widely distributed marine diazotroph lineages. Inside the mesocosms, the most abundant diazotroph was the heterocyst-forming Richelia associated with Rhizosolenia (Het-1) in the first half of the experiment, while unicellular cyanobacterial Group C (UCYN-C) became abundant during the second half of the experiment. Decreasing DIP concentrations following the fertilization event and increasing temperatures were significantly correlated with increasing abundances of UCYN-C. Maximum net growth rates for UCYN-C were calculated to range between 1.23 ± 0.07 and 2.16 ± 0.07 d-1 in the mesocosms, which are among the highest growth rates reported for diazotrophs. Outside the mesocosms in the New Caledonia lagoon, UCYN-C abundances remained low, despite increasing temperatures, suggesting that the microbial community response to the DIP fertilization created conditions favorable for UCYN-C growth inside the mesocosms. Diazotroph community composition analysis using PCR targeting a component of the nitrogenase gene (nifH) verified that diazotrophs targeted in qPCR assays were collectively among the major lineages in the lagoon and mesocosm samples, with the exception of Crocosphaera-like phylotypes, where sequence types not typically seen in the oligotrophic ocean grew in the mesocosms. Maximum net growth and mortality rates for nine diazotroph phylotypes throughout the 23-day

  19. Water-quality monitoring and biological integrity assessment in the Indian River Lagoon, Florida: Status, trends, and loadings (1988--1994)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sigua, G.C.; Steward, J.S.; Tweedale, W.A.

    2000-02-01

    The Indian River Lagoon (IRL) system that extends from Ponce DeLeon inlet to Jupiter inlet is comprised of three interconnected estuarine lagoons: The Mosquito Lagoon (ML), the Banana River Lagoon (BRL), and the Indian River Lagoon. The declines in both the aerial coverage and species diversity of seagrass communities within the IRL system are believed to be due in part to continued degradation of water quality. Large inflows of phosphorus (P) and nitrogen (N)-laden storm-water from urban areas an agricultural land have been correlated with higher chlorophyll a production in the central, south central, and the south segments of themore » lagoon. In a system as large and complex as the lagoon, N and P limitations are potentially subject to significant spatial and temporal variability. Total Kjeidahl nitrogen (TN) was higher in the north and lower in the south. The reverse pattern was observed for total P (TP), i.e., lowest in the north and highest at the south ends of the IRL. This increased P concentration in the SIRL appears to have a significantly large effect on chlorophyll a production compared with the other segments, as indicated by stepwise regression statistics. This relationship can be expressed as follows: South IRL [chlorophyll a] = {minus}8.52 + 162.41 [orthophosphate] + 7.86 [total nitrogen] + 0.38 [turbidity]; R{sup 2} = 0.98**.« less

  20. Spatial variations in dietary organic matter sources modulate the size and condition of fish juveniles in temperate lagoon nursery sites

    NASA Astrophysics Data System (ADS)

    Escalas, Arthur; Ferraton, Franck; Paillon, Christelle; Vidy, Guy; Carcaillet, Frédérique; Salen-Picard, Chantal; Le Loc'h, François; Richard, Pierre; Darnaude, Audrey Michèle

    2015-01-01

    Effective conservation of marine fish stocks involves understanding the impact, on population dynamics, of intra-specific variation in nursery habitats use at the juvenile stage. In some regions, an important part of the catching effort is concentrated on a small number of marine species that colonize coastal lagoons during their first year of life. To determine the intra-specific variation in lagoon use by these fish and their potential demographic consequences, we studied diet spatiotemporal variations in the group 0 juveniles of a highly exploited sparid, the gilthead seabream (Sparus aurata L.), during their ∼6 months stay in a NW Mediterranean lagoon (N = 331, SL = 25-198 mm) and traced the origin of the organic matter in their food webs, at two lagoon sites with contrasted continental inputs. This showed that the origin (marine, lagoonal or continental) of the organic matter (OM) available in the water column and the sediment can vary substantially within the same lagoon, in line with local variations in the intensity of marine and continental inputs. The high trophic plasticity of S. aurata allows its juveniles to adapt to resulting differences in prey abundances at each site during their lagoon residency, thereby sustaining high growth irrespective of the area inhabited within the lagoon. However, continental POM incorporation by the juveniles through their diet (of 21-37% on average depending on the site) is proportional to its availability in the environment and could be responsible for the greater fish sizes (of 28 mm SL on average) and body weights (of 40.8 g on average) observed at the site under continental influence in the autumn, when the juveniles are ready to leave the lagoon. This suggests that continental inputs in particulate OM, when present, could significantly enhance fish growth within coastal lagoons, with important consequences on the local population dynamics of the fish species that use them as nurseries. As our results indicate that

  1. Facultative Lagoons. Instructor's Guide. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Andersen, Lorri

    This instructor's guide contains materials needed to teach a two-lesson unit on the structure and components of facultative lagoons, the biological theory of their operation, and factors affecting their operation. Control testing recommendations, maintenance guidelines, and troubleshooting hints are also provided. These materials include: (1) an…

  2. TENDENCIA DE LA TUBERCULOSIS EN LA REGIÓN SANITARIA V DE LA PROVINCIA DE BUENOS AIRES, AÑOS 2000–2011

    PubMed Central

    CHIRICO, CRISTINA; SANJURJO, MYRIAM; IRIBARREN, SARAH; APPENDINO, ANDREA; ZERBINI, ELSA; ETCHEVARRIA, MIRTA

    2016-01-01

    El objetivo del presente trabajo fue analizar la situación epidemiológica de la tuberculosis (TB) en la Región Sanitaria V (RSV), provincia de Buenos Aires. El estudio de tendencia permitió conocer un valor promedio de las variaciones de la tasa de incidencia (TI), calculadas por regresión lineal simple y expresadas como variación anual promedio (VAP). Se analizaron el número de casos notificados y TI por 100 000 habitantes de todas las formas de TB, los casos de TB pulmonar (TBP) y TBP confirmados por bacteriología, total casos por grupos de edad: 0 – 14; 15 – 29 y mayores de 64 años, entre el 1° de enero de 2000 al 31 de diciembre de 2011. La declinación de la TI fue menor al 5% para todas las formas de TB e inferior en las TBP confirmadas bacteriológicamente. Los casos de TBP y TI más elevadas, se concentraron en el grupo de 15 a 29 años, con tendencia estable o ligeramente ascendente de la TI en la TBP bacilífera. El mismo comportamiento presentaron los casos de TBP infantil con confirmación bacteriológica. La mayor velocidad de descenso en la TI de la TBP se produjo en este grupo de edad, mientras que en mayores de 64 años, el descenso fue sostenido en el tiempo. La TB persiste como un riesgo de salud en la RSV, con casos en edades jóvenes, por lo que sigue siendo necesario fortalecer el control de la TB en esta región. PMID:26117604

  3. Effect of climate change and mollusc invasion on eutrophication and algae blooms in the lagoon ecosystems of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Aleksandrov, Sergei; Gorbunova, Julia; Rudinskaya, Lilia

    2015-04-01

    Coastal lagoons are most vulnerable to impacts of natural environmental and anthropogenic factors. The Curonian Lagoon and Vistula Lagoon are the largest coastal lagoons of the Baltic Sea, relating to the most highly productive water bodies of Europe. The Curonian Lagoon is choke mostly freshwater lagoon, while the Vistula Lagoon is restricted brackish water lagoon. In the last decades the nutrients loading changes, warming trend and biological invasions are observed. The researches (chlorophyll, primary production, nutrients, phytoplankton, benthos, etc) were carried out monthly since 1991 to 2014. The database includes 1600 stations in the Curonian Lagoon, 1650 stations in the Vistula Lagoon. Eutrophication and algae blooms are most important problems. Multiple reductions of nutrients loading from the watershed area in 1990s did not result in considerable improvement of the ecological situation in the lagoons. The Curonian Lagoon may be characterized as hypertrophic water body with "poor" water quality. Climate change in 1990s-2000s combined with other factors (freshwater, slow-flow exchange, high nutrients concentrations) creates conditions for Cyanobacteria "hyperblooms". Hyperbloom of Cyanophyta (average for the growing season Chl > 100 μg/l) were observed during 4 years in 1990s and 7 years in 2000s. The summer water temperature is the key environmental factor determining the seasonal and long-term variability of the primary production and algae blooms. Mean annual primary production in 2010-2014 (600 gC·m-2·year-1) is considerable higher, than in the middle of 1970s (300 gC·m-2·year-1). The local climate warming in the Baltic region caused ongoing eutrophication and harmful algae blooms in the Curonian Lagoon despite of significant reduction of nutrients loading in 1990s-2000s. Harmful algal blooms in July-October (chlorophyll to 700-3400 μg/l) result in deterioration of the water chemical parameters, death of fish in the coastal zone and pollution

  4. WISE Catches the Lagoon Nebula in Center of Action

    NASA Image and Video Library

    2011-01-06

    This colorful picture is a mosaic of Messier 8, or the Lagoon nebula, taken by NASA Wide-field Infrared Survey Explorer. This nebula is composed of clouds of gas and dust in which new stars are forming.

  5. Assessing Pathogen Levels in Dairy Lagoon Wastewater and Potential Evaporation Losses

    NASA Astrophysics Data System (ADS)

    Pandey, P.; Biswas, S.; Souza, A.; Silva-del-Rio, N.; Vaddella, V. K.; Castillo, A. R.

    2014-12-01

    The ongoing drought in California necessitates the conservation of existing water resources while protecting the water quality. There is a critical need to improve the understanding of evaporation losses from dairy lagoons in California, and their corresponding changes in pathogen levels in the lagoon wastewater. We have carried out preliminary studies involving extensive dairy lagoon water sampling, and batch-scale experiments. The dairy wastewater was collected from both primary and secondary lagoons in three counties of California (Merced, Tulare, and Glenn Counties) for enumerating the levels of E. coli O157:H7, Salmonella spp., and Listeria monocytogenes. Subsequently, we conducted batch-scale experiments at mesophilic (31 and 37 ⁰C) and thermophilic temperatures (43 and 49 ⁰C) to understand the E. coli O157:H7 inactivation process and potential evaporative water losses. In addition, we compared the evaporation losses under the environment of biological activity and the environment of restricted biological activity (extreme environment with low pH). For E. coli O157:H7 enumeration, we used MacConkey agar, while for Salmonella spp., XLD agar was used. Listeria monocytogenes levels were measured using PALCAM agar (with selective supplement). In flushed dairy wastewater (fresh) samples, the average of E. coli O157:H7 levels were 2 × 104 CFU/mL. The average Listeria monocytogenes levels in flushed manure were 9 × 101. The levels of Salmonella spp. were non-detectable. In mesophilic condition (37 ⁰C) after 5 days of incubation, 8% of total water loss was observed, while at thermophilic temperature (49 ⁰C), 70% of total water loss was observed. After 5 days of incubation at 37 ⁰C, E. coli O157:H7 levels in flushed dairy manure were increased from 2.8 × 103 to 5.2 × 104 CFU/mL, while at 49 ⁰C, E. coli O157:H7 levels were reduced from 2.8 × 103 to 5 × 101 CFU/mL after 4 days of incubation. We anticipate that the results of this study would be useful

  6. Dynamics of pollution-indicator and heterotrophic bacteria in sewage treatment lagoons.

    PubMed

    Legendre, P; Baleux, B; Troussellier, M

    1984-09-01

    The spatio-temporal dynamics of pollution-indicator bacteria and aerobic heterotrophic bacteria were studied in the sewage treatment lagoons of an urban wastewater center after 26 months of biweekly sampling at eight stations in these lagoons. Robust statistical methods of time-series analysis were used to study successional steps (through chronological clustering) and rhythmic behavior through time (through contingency periodogram). The aerobic heterotrophic bacterial community showed two types of temporal evolution: in the first four stations, it seems mainly controlled by the nutrient support capacity of the sewage input, whereas in the remaining part of the lagoon, it seems likely that the pollution-indicator bacteria are gradually replaced by other bacterial types that are better adapted to this environment. On the other hand, the pollution-indicator bacteria showed an annual cycle which increased in amplitude at distances further from the wastewater source. The main events in this cycle were produced simultaneously at all stations, indicating control of these bacterial populations by climatic factors, which act through physical and chemical factors, and also through other biological components of this ecosystem (phytoplankton and zooplankton). Finally, we use results from this study to suggest a modified design for a future study program.

  7. Amount and type of derelict gear from the declining black pearl oyster aquaculture in Ahe atoll lagoon, French Polynesia.

    PubMed

    Andréfouët, Serge; Thomas, Yoann; Lo, Cedrik

    2014-06-15

    Pearl oyster aquaculture is a major activity in French Polynesia atoll lagoons. After the economic decline that characterized the last decade, concerns recently rose about discarded installations and materials that supported aquaculture practices and by facilities abandoned after they had to close their activities. In May 2013, a first inventory of the type and amount of pearl farms derelict gear (PFDG) was achieved on 47 sites in Ahe lagoon. Surveys were conducted within and outside the boundaries of aquaculture concessions. Twenty types of PFDG littered the lagoon floor and the water column. The most impacted areas were near abandoned grafting houses with up to nine types of PFDG. Forty-five percent of the sites were impacted, including outside concessions. While management authorities are fully aware of the problem, this first assessment is a wake-up call to stimulate the cleaning of lagoons, enhance awareness among farmers, and identify potential ecological consequences on lagoon ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Hatching rhythms and dispersion of decapod crustacean larvae in a brackish coastal lagoon in Argentina

    NASA Astrophysics Data System (ADS)

    Anger, K.; Spivak, E.; Bas, C.; Ismael, D.; Luppi, T.

    1994-12-01

    Mar Chiquita, a brackish coastal lagoon in central Argentina, is inhabited by dense populations of two intertidal grapsid crab species, Cyrtograpsus angulatus and Chasmagnathus granulata. During a preliminary one-year study and a subsequent intensive sampling programme (November December 1992), the physical properties and the occurrence of decapod crustacean larvae in the surface water of the lagoon were investigated. The lagoon is characterized by highly variable physical conditions, with oligohaline waters frequently predominating over extended periods. The adjacent coastal waters show a complex pattern of semidiurnal tides that often do not influence the lagoon, due to the existence of a sandbar across its entrance. Besides frequently occurring larvae (exclusively freshly hatched zoeae and a few megalopae) of the two dominating crab species, those of three other brachyurans ( Plathyxanthus crenulatus, Uca uruguayensis, Pinnixa patagonica) and of one anomuran (the porcellanid Pachycheles haigae) were also found occasionally. Caridean shrimp ( Palaemonetes argentinus) larvae occurred in a moderate number of samples, with a maximum density of 800·m-3. The highest larval abundance was recorded in C. angulatus, with almost 8000°m-3. Significantly more C. angulatus and C. granulata zoeae occurred at night than during daylight conditions, and more larvae (statistically significant only in the former species) during ebb (outflowing) than during flood (inflowing) tides. In consequence, most crab zoeae were observed during nocturnal ebb, the least with diurnal flood tides. Our data suggest that crab larvae do not develop in the lagoon, where the adult populations live, but exhibit an export strategy, probably based upon exogenously coordinated egg hatching rhythms. Zoeal development must take place in coastal marine waters, from where the megalopa eventually returns for settlement and metamorphosis in the lagoon. Significantly higher larval frequency of C. granulata in

  9. The ecological status of Karavasta Lagoon (Albania): Closing the stable door before the horse has bolted?

    PubMed

    Munari, Cristina; Tessari, Umberto; Rossi, Remigio; Mistri, Michele

    2010-02-01

    Karavasta is the widest and most important lagoon in Albania. This study aimed to assess the ecological quality status of the lagoon, acquire knowledge of a natural environment which might be exploited for aquaculture, and give management hints on the basis of anthropogenic impact and ecological conditions. A sampling campaign was carried out in 2008: at six stations, benthic fauna, water, and sediment parameters were considered. Statistical analyses were carried out through multivariate procedures (PCA, classification-clustering, SIMPER, RDA, DISTLM, PERMANOVA). Ecological quality was assessed through the AZTI Marine Biotic Index (AMBI), the multivariate AMBI (M-AMBI) and the Benthic Index based on Taxonomic Sufficiency (BITS). Sediment characteristics (percent organic matter, %OM; redox potential discontinuity layer depth, RPDL; particle size composition) and salinity represented contributory influences on lagoon communities. It was possible to distinguish and characterise a confined area, and benthic communities, from a marine-influenced area and its biota. The number of species was quite low when compared with other open Adriatic lagoons. The M-AMBI and BITS classifications gave quite similar results, which seemed consistent with the ecological conditions of the lagoon, that is a distinction in the ecological quality between the seaward and landward stations, with higher ecological quality (EcoQ) at the seaward stations. Given the pressures and the ecological condition of Karavasta, an intensification of aquaculture activities must be considered with caution, since the lagoon seems at significant risk of serious hypereutrophication. This situation is made worse by the limited water exchange with the marine environment due to the irregular dredging of the communication channels. 2009 Elsevier Ltd. All rights reserved.

  10. Does coastal lagoon habitat quality affect fish growth rate and their recruitment? Insights from fishing and acoustic surveys

    NASA Astrophysics Data System (ADS)

    Brehmer, P.; Laugier, T.; Kantoussan, J.; Galgani, F.; Mouillot, D.

    2013-07-01

    Ensuring the sustainability of fish resources necessitates understanding their interaction with coastal habitats, which is becoming ever more challenging in the context of ever increasing anthropogenic pressures. The ability of coastal lagoons, exposed to major sources of disturbance, to provide resources and suitable habitats for growth and survival of juvenile fish is especially important. We analysed three lagoons with different ecological statuses and habitat quality on the basis of their eutrophication and ecotoxicity (Trix test) levels. Fish abundances were sampled using fishing and horizontal beaming acoustic surveys with the same protocols in the same year. The relative abundance of Anguilla anguilla, Dicentrarchus labrax or the Mugilidae group was not an indicator of habitat quality, whereas Atherina boyeri and Sparus aurata appeared to be more sensitive to habitat quality. Fish abundance was higher in the two lagoons with high eutrophication and ecotoxicity levels than in the less impacted lagoon, while fish sizes were significantly higher in the two most severely impacted lagoons. This leads us to suggest low habitat quality may increase fish growth rate (by the mean of a cascading effect), but may reduce lagoon juvenile abundance by increasing larval mortality. Such a hypothesis needs to be further validated using greater investigations which take into account more influences on fish growth and recruitment in such variable environments under complex multi-stressor conditions.

  11. Effects of rainfalls variability and physical-chemical parameters on enteroviruses in sewage and lagoon in Yopougon, Côte d'Ivoire

    NASA Astrophysics Data System (ADS)

    Momou, Kouassi Julien; Akoua-Koffi, Chantal; Traoré, Karim Sory; Akré, Djako Sosthène; Dosso, Mireille

    2017-07-01

    The aim of this study was to assess the variability of the content of nutrients, oxidizable organic and particulate matters in raw sewage and the lagoon on the effect of rainfall. Then evaluate the impact of these changes in the concentration of enteroviruses (EVs) in waters. The sewage samples were collected at nine sampling points along the channel, which flows, into a tropical lagoon in Yopougon. Physical-chemical parameters (5-day Biochemical Oxygen Demand, Chemical Oxygen Demand, Suspended Particulate Matter, Total Phosphorus, Orthophosphate, Total Kjeldahl Nitrogen and Nitrate) as well as the concentration of EV in these waters were determined. The average numbers of EV isolated from the outlet of the channel were 9.06 × 104 PFU 100 ml-1. Consequently, EV was present in 55.55 and 33.33 % of the samples in the 2 brackish lagoon collection sites. The effect of rainfall on viral load at the both sewage and brackish lagoon environments is significant correlate (two-way ANOVA, P < 0.05). Furthermore, in lagoon environment, nutrients (Orthophosphate, Total Phosphorus), 5-day Biochemical Oxygen Demand, Chemical Oxygen Demand and Suspended Particulate Matter were significant correlated with EVs loads ( P < 0.05 by Pearson test). The overall results highlight the problem of sewage discharge into the lagoon and correlation between viral loads and water quality parameters in sewage and lagoon.

  12. Structure and diversity of fishes in a freshwater and coastal subtropical lagoon.

    PubMed

    Ferreira, N C; Guereschi, R M; Machado, C; Lopes, C A; Nuñer, A P O

    2017-04-01

    This study examined the fish communities of Peri Lagoon in southern Brazil to aid in the development of an effective management plan because the area is under threat from human activities. Sampling of fish fauna, ichthyoplankton and limnological data were compared between sites, differing by habitat type and characteristics such as depth, substratum composition and vegetation type. Results were significantly related to site, with the highest diversity and abundance recorded at shallow vegetated sites. A total of 14 fish species were recorded throughout the lagoon, with the most abundant being Hyphessobrycon luetkenii. Of the 14 species, half were sampled at their larval stage, suggesting a healthy and protected system. Significantly more larvae and eggs were collected during colder months (autumn to winter) and at sites closer to stream flow, possibly owing to increased food sources and habitat protection. This study highlights the importance of Peri Lagoon as a nursery ground for a wide range of fish species, providing essential information for incorporation into the future protection of fish stocks throughout Brazil. © 2016 The Fisheries Society of the British Isles.

  13. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon

    PubMed Central

    Pantos, Olga; Morgan, Thomas C.; Rich, Virginia; Tonin, Hemerson; Bourne, David G.; Mercurio, Philip; Negri, Andrew P.; Tyson, Gene W.

    2016-01-01

    Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR) lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L), and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems. PMID:26989611

  14. Transport of steroid hormones, phytoestrogens, and estrogenic activity across a swine lagoon/sprayfield system.

    PubMed

    Yost, Erin E; Meyer, Michael T; Dietze, Julie E; Williams, C Michael; Worley-Davis, Lynn; Lee, Boknam; Kullman, Seth W

    2014-10-07

    The inflow, transformation, and attenuation of natural steroid hormones and phytoestrogens and estrogenic activity were assessed across the lagoon/sprayfield system of a prototypical commercial swine sow operation. Free and conjugated steroid hormones (estrogens, androgens, and progesterone) were detected in urine and feces of sows across reproductive stages, with progesterone being the most abundant steroid hormone. Excreta also contained phytoestrogens indicative of a soy-based diet, particularly, daidzein, genistein, and equol. During storage in barn pits and the anaerobic lagoon, conjugated hormones dissipated, and androgens and progesterone were attenuated. Estrone and equol persisted along the waste disposal route. Following application of lagoon slurry to agricultural soils, all analytes exhibited attenuation within 2 days. However, analytes including estrone, androstenedione, progesterone, and equol remained detectable in soil at 2 months postapplication. Estrogenic activity in the yeast estrogen screen and T47D-KBluc in vitro bioassays generally tracked well with analyte concentrations. Estrone was found to be the greatest contributor to estrogenic activity across all sample types. This investigation encompasses the most comprehensive suite of natural hormone and phytoestrogen analytes examined to date across a livestock lagoon/sprayfield and provides global insight into the fate of these analytes in this widely used waste management system.

  15. Transport of Steroid Hormones, Phytoestrogens, and Estrogenic Activity across a Swine Lagoon/Sprayfield System

    PubMed Central

    Yost, Erin E.; Meyer, Michael T.; Dietze, Julie E.; Williams, C. Michael; Worley-Davis, Lynn; Lee, Boknam; Kullman, Seth W.

    2017-01-01

    The inflow, transformation, and attenuation of natural steroid hormones, phytoestrogens, and estrogenic activity was assessed across the lagoon/sprayfield system of a prototypical commercial swine sow operation. Free and conjugated steroid hormones (estrogens, androgens, and progesterone) were detected in urine and feces of sows across reproductive stages, with progesterone being the most abundant steroid hormone. Excreta also contained phytoestrogens indicative of a soy-based diet; particularly daidzein, genistein, and equol. During storage in barn pits and the anaerobic lagoon, conjugated hormones dissipated, and androgens and progesterone were attenuated. Estrone and equol persisted along the waste disposal route. Following application of lagoon slurry to agricultural soils, all analytes exhibited attenuation within 2 days. However, analytes including estrone, androstenedione, progesterone, and equol remained detectable in soil at two months post-application. Estrogenic activity in the yeast estrogen screen and T47D-KBluc in vitro bioassays generally tracked well with analyte concentrations. Estrone found to be the greatest contributor to estrogenic activity across all sample types. This investigation encompasses the most comprehensive suite of natural hormone and phytoestrogen analytes examined to date across a lagoon/sprayfield system, and provides global insight into the fate of these analytes in this widely used waste management system. PMID:25148584

  16. Resolving land subsidence within the Venice Lagoon by persistent scatterer SAR interferometry

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Tosi, L.; Strozzi, T.; Carbognin, L.; Cecconi, G.; Rosselli, R.; Libardo, S.

    Land subsidence is a severe geologic hazard threatening the lowlying transitional coastal areas worldwide. Monitoring land subsidence has been significantly improved over the last decade by space borne earth observation techniques based on Synthetic Aperture Radar (SAR) interferometry. Within the INLET Project, funded by Magistrato alle Acque di Venezia - Venice Water Authority (VWA) and Consorzio Venezia Nuova (CVN), we use Interferometric Point Target Analysis (IPTA) to characterize the ground displacements within the Venice Lagoon. IPTA measures the movement of backscattering point targets (PTs) at the ground surface that persistently reflect radar signals emitted by the SAR system at different passes. For this study 80 ERS-1/2 and 44 ENVISAT SAR scenes recorded from 1992 to 2005 and from 2003 to 2007, respectively, have been processed. Highly reliable displacement measurements have been detected for thousands of PTs located on the lagoon margins, along the littorals, in major and small islands, and on single structures scattered within the lagoon. On the average, land subsidence ranges from less than 1 mm/year to 5 mm/year, with some PTs that exhibit values also larger than 10 mm/year depending on both the local geologic conditions and the anthropic activities. A network of a few tens of artificial square trihedral corner reflectors (TCRs) has been established before summer 2007 in order to monitor land subsidence in the inner lagoon areas where “natural” reflectors completely lack (e.g., on the salt marshes). The first interferometric results on the TCRs appear very promising.

  17. Estimating greenhouse gas emissions from a waste lagoon

    USDA-ARS?s Scientific Manuscript database

    A cost-effective approach was used to investigate the relationship between emission of the greenhouse gases (GHG) CO2, CH4, and N2O and energy fluxes from a swine waste lagoon. Energy fluxes were calculated using the Penman method. The energy fluxes showed a diurnal pattern as expected of such flux...

  18. An early work [1910-1913] in Biological Psychology by pioneer psychiatrist, criminologist and philosopher José Ingenieros, M.D. (1877-1925) of Buenos Aires.

    PubMed

    Triarhou, Lazaros C; del Cerro, Manuel

    2006-04-01

    One of the earliest recorded works in Biological Psychology was published in 1910 by Argentine psychiatrist José Ingenieros (1877-1925), Professor of Experimental Psychology at the Faculty of Philosophy and Letters of the University of Buenos Aires. Ingenieros, a multifaceted personality and prolific author and educator famous for his lapidary aphorisms, has been considered a 'luminary' for generations. Trained as a physician, he was the first scientist to establish a comprehensive psychological system in Latin America. His long list of publications includes more than 300 titles generally divided in two periods: studies in mental pathology and criminology (1897-1908) and studies in philosophy, psychology and sociology (1908-1925). His works were never made particularly available to English-speaking audiences, despite the fact that certain of his books are still best-sellers in the Spanish-speaking world. We present an overview of Ingenieros' life and work, and a detailed account of his profoundly interesting work Principios de Psicología Biológica, in which he analyzes the development, evolution and social context of mental functions. We also provide an English translation of the Introduction contributed by Nobel laureate Wilhelm Ostwald (1853-1932) to the 1922 German edition of the work, pertinent to the energetic principles Ingenieros used and the study of Psychology as a natural science. It is a hope, 80 years after Ingenieros' parting, to bibliographically resurrect this champion of reason, who, until now, has not been given his due placement in the international psychological and biomedical literature.

  19. SPREADING LAGOONED SEWAGE SLUDGE ON FARMLAND: A CASE HISTORY

    EPA Science Inventory

    This project demonstrated that land application is feasible and practical for a metropolitan treatment plant for disposal of a large volume (265,000 cu m) of stabilized, liquid sewage sludge stored in lagoons. The project involved transportation of sludge by semi-trailer tankers ...

  20. Organotins' fate in lagoon sewage system: dealkylation and sludge sorption/desorption.

    PubMed

    Ophithakorn, Thiwari; Sabah, Aboubakr; Delalonde, Michele; Bancon-Montigny, Chrystelle; Suksaroj, Thunwadee Tachapattaworakul; Wisniewski, Christelle

    2016-11-01

    Organotin compounds (OTs) have been widely used for their biocidal properties and as stabilizers in various industrial applications. Due to their high toxicity, organotins are subject to many studies regarding their behavior in wastewater treatment plant and aquatic environment. However, few studies are available regarding their behavior in lagoon sewage system, although such treatment is commonly used for sewage treatment in low-population areas. The present study aimed at studying the fate of organotins (monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT)) in lagoon sewage system. Short-term experiments, carried out at lab scale, consisted in sampling sludge from aerobic stabilization ponds, and then quantifying sorption and desorption of the different organotin species, as well as their respective transformation, under defined operating conditions (e.g., tributyltin spike and dilution) simulating possible change in the surrounding environment of sludge in the lagoon. Results established that a very important percentage of the OTs was localized in the solid phase of the sludge (more than 98 %), whatever the operating conditions may be; however, transformation and locations of the three OT species differed according to the different conditions of sludge dilution, TBT spiking, and test duration. After dilution of lagoon sludge, TBT desorption from sludge was observed; it was supposed that dealkylation of TBT after desorption occurred rapidly and increased dissolved MBT and DBT in liquid phase; MBT sorbed subsequently on solid phase. The nature of the diluent (i.e., tap water or saline solution) appeared to slightly influence the sludge behavior. After TBT spiking, TBT was supposed to be rapidly sorbed but also transformed in DBT and MBT that would as well sorbed on the sludge, which explained the decrease of these species in the liquid phase. Tests aimed at studying long-term effect of TBT spiking demonstrated that the sorbed species could be remobilized

  1. Using hydrochemistry, tracers and isotopes to analyze hydrogeological dynamics and eutrophication processes in coastal lagoons

    NASA Astrophysics Data System (ADS)

    Menció, Anna; Mas-Pla, Josep; Quintana, Xavier D.

    2016-04-01

    Wetlands and coastal lagoons in Mediterranean areas have recently been the focus of an increasing interest due to the degradation of their ecological status in terms of declining biodiversity, alteration of ecological functioning and limitation of the ecosystem services they provide. Accordingly, the Horizon 2020 Programme of the European Union has set, as one of its priorities, to prevent a further degradation of these ecosystems and to recover their ecological functioning. The aim of this project is to analyze the hydrogeological dynamics in the Pletera coastal lagoons (NE, Spain) as a basis to propose guidelines for their sustainable management. Thus, monthly hydrochemical (with major ions, nutrients and tracers) and isotopic (δ18OH2O and δD) campaigns have been conducted, from November 2014 to October 2015, to determine the hydrogeological dynamics of the Pletera lagoons. In addition, in some of the sampling campaigns δ34SSO4, δ18OSO4, δ15NNO3 and δ18ONO3 have also been analyzed to determine the origin of eutrophication problems observed in these lagoons, mainly caused by nitrogen compounds. Project founded by MEC CGL-2014-57215-C4-2R and LIFE 13 NAT/ES/001001

  2. Aghien lagoon: a sustainable resource of fresh water for the city of Abidjan (Ivory Coast)? Description of the project and preliminary results

    NASA Astrophysics Data System (ADS)

    Kamagaté, Bamory; Effebi, Rose K.; Goula Bi, Tié Albert; Lanciné Goné, Droh; Noufé, Djibril; Diallo, Seydou; Ehouman, Serge K.; Koffi, Thierry; Zamblé Trabi, Armand; Lazare, Kouakou; Paturel, Jean Emmanuel; Perrin, Jean-Louis; Salles, Christian; Seguis, Luc; Tournoud, Marie-George; Karoui, Hela

    2016-04-01

    With more than 6 million inhabitants, Abidjan district faces tremendous difficulties in water supply. The aquifer of the Continental Terminal which is actually the only drinking water source of the city shows a decline of resources and water demand is increasing due to the population growth. Moreover significant evidences of chemical and biological pollution of the groundwater are observed The Aghien lagoon, the largest freshwater pool located near Abidjan, has been identified by the State of Côte d'Ivoire as a potential resource for the production of drinking water.. The main objective of this project is to assess the quantitative and qualitative capacity of the Aghien lagoon to complement the water supply of Abidjan city in the near future. The main components of the project are: • to assess the water budget of the lagoon and its tributaries, • to characterize the spatial and temporal variability of contaminant levels and fluxes from the tributaries toward the lagoon, • to assess the sustainability of the water resources (quantity and quality) of the lagoon according to land use changes in the catchments . The project started in January 2015. The first year was devoted to the set-up of hydro-meteorological gauges within the lagoon watershed. Three major tributaries of the lagoon are considered, the Mé (4000 km2), the Djibi (78 km2) and Bete (206 km2) rivers. Since the start of the project, bi-monthly hydrochemical sampling surveys have been carried out along the tributaries and in the lagoon. The data available from the surveys concern the physico-chemical parameters, trace elements, all the forms of nitrogen and phosphorus, organic carbon, suspended solids. The Djibi and Bete watersheds are partly urbanized while the Mé basin is mainly rural. Baseflow has been identified as the major contribution to streamflow at the annual scale. The Mé flows into a channel downstream to the Aghien lagoon but during the floods, water from the Mé River can flow up the

  3. Hydrological heterogeneity, nutrient dynamics and water quality of a non-tidal lentic ecosystem (Lesina Lagoon, Italy)

    NASA Astrophysics Data System (ADS)

    Roselli, Leonilde; Fabbrocini, Adele; Manzo, Cristina; D'Adamo, Raffaele

    2009-10-01

    The dynamics of the Lesina coastal lagoon (Italy) in terms of nutrients, phytoplankton and chemical-physical parameters were evaluated, together with their functional relationships with freshwater inputs, in order to identify ecosystem responses to changes in driving forces in a Mediterranean non-tidal lentic environment. Lesina Lagoon is a shallow coastal environment characterised by limited exchange with coastal waters, which favours enrichment of nutrients and organic matter and benthic fluxes within the system. Lagoon-sea exchanges are influenced by human management. There is a steep salinity gradient from East to West. High nitrogen and silica values were found close to freshwater inputs, indicating wastewater discharges and agricultural runoff, especially in winter. Dissolved oxygen was well below saturation (65%) near sewage and runoff inputs in the western part of the lagoon during summer. Classification in accordance with EEA (2001) guidelines suggests the system is of "poor" or "bad" quality in terms of nitrogen concentrations in the eastern zone during the winter rainy period. In terms of phosphate concentrations, the majority of the stations fall into the "good" category, with only two stations (close to the sewage and runoff inputs) classed as "bad". In both cases, the raw nitrogen levels make the lagoon a P-limited system, especially in the eastern part. There was wide space-time variability in chlorophyll a concentrations, which ranged from 0.25 to 56 μg l -1. No relationships between chlorophyll a and nutrients were found, suggesting that autotrophic biomass may be controlled by a large number of internal and external forcing factors driving eutrophication processes. Water quality for this type of environment depends heavily on pressure from human activities but also on the management of sewage treatment plants, agricultural practices and the channels connecting the lagoon with the sea.

  4. Radiochemical methodology for the determination of the mass balance of suspended particulate materials exchanged at the inlets of the Venice Lagoon

    NASA Astrophysics Data System (ADS)

    Degetto, S.; Cantaluppi, C.

    2004-11-01

    The Venice Lagoon is connected to the Adriatic Sea by three inlets, with an average daily water inflow of 345∗10 6 m 3. Due to the diversion of the major rivers out of the lagoon (done in the past centuries), the sediment supply from the drainage basin is now very low when compared to the amount of sediment exchanged at the inlets (<1%). The limited sediment supply and the combined action of natural and anthropic pressures (e.g. waves, ships, fishing activities, dredging for navigation purposes) have caused in the last few decades a significant erosion of mudflats and salt-marshes. In order to investigate the history and the characteristics of the above phenomenon, with particular regard to the most recent years and the future trend, a wide radiochemical survey has been carried out in the whole lagoon, including the characterisation of the suspended particulate matter entering and leaving the lagoon in different tidal and meteorological conditions, with the aim of obtaining an indirect estimate of the sediment mass balance of the lagoon. The proposed radiochemical methodology, which is based on concentration measurements of airborne radionuclides in suspended particulate matter, appears to be an useful alternative to direct methods (e.g. bathymetric campaigns in the lagoon or mass fluxes measurements of the suspended particulate materials exchanged at the inlets). The results obtained, which show a complex sedimentary situation, highlight the erosion acting in some central and southern lagoon areas but recognise also the present accumulation phase coming into view in the northern lagoon.

  5. Dioxins in the Venice lagoon: Present situation, projects and recovering hypotheses.

    PubMed

    Raccanelli, S; Bonamin, V

    2000-01-01

    Venice is famous around the world for its uniqueness and architectural splendours, arts and the history of the "Serenissima Repubblica", as it was known in the past, but few are aware that Venice economy is strongly dependent on the industrial activities based mainly on the adjacent Porto Marghera area. For many years, the lagoon that physically separates the city from the dry land has avoided association between the concern connected with the pollution derived from these industrial activities and the public perception of Venice. Since 1995, dioxins have appeared as a lagoon contaminant, and their presence, at such a level requiring immediate "in depth" studies and interventions, has been fully realized for decades.

  6. 75 FR 53299 - Issuance of NPDES General Permits for Wastewater Lagoon Systems Located in Indian Country in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9195-3] Issuance of NPDES General Permits for Wastewater... Elimination System (NPDES) general permits for wastewater lagoon systems that are located in Indian country in... general permit for wastewater lagoon systems that are located in Indian country in the State of Colorado...

  7. Assessment of hydrologic and water quality data collected in Abbotts Lagoon watershed, Point Reyes National Seashore, California, during water years 1999 and 2000

    USGS Publications Warehouse

    Kratzer, Charles R.; Saleh, Dina K.; Zamora, Celia

    2006-01-01

    Abbotts Lagoon is part of Point Reyes National Seashore, located about 40 miles northwest of San Francisco and about 20 miles south of Bodega Bay. Water-quality samples were collected quarterly during water year 1999 at a site in each of three connected lagoons that make up Abbotts Lagoon and at a site in its most significant tributary. The quarterly samples were analyzed for major ions, nutrients, and chlorophyll-a. A bed-sediment sample was collected in each lagoon during August 1999 and was analyzed for organic carbon, iron, and total phosphorus. Seven tributaries were sampled during a February 1999 storm and four during an April 1999 storm. These samples were analyzed only for nutrients. One storm sample collected in April 1999 from a tributary downstream of the I Ranch dairy was analyzed for a suite of 47 compounds indicative of wastewater. Continuous water-level recorders were installed in the most significant tributary and the two largest lagoons for portions of the study. A water budget analysis for an April 2000 storm indicated that the main tributary accounted for 85 percent of surface inflows to Abbotts Lagoon. The portion of the surface inflow from the main tributary was lower in the February 1999 storms and is a function of upstream storage and vegetative growth in the tributary basins. Another water budget analysis for a period of no surface inflow (June and July 2000) indicated that the net ground-water contribution was an outflow (seepage) from Abbotts Lagoon of about 0.3 ft3/s. Salinity increased and nutrient concentrations decreased from upstream to downstream in the chain of lagoons. The lower lagoon, nearest the ocean, had less organic carbon and total phosphorus in the bed sediment than the upper lagoons. The two tributaries originating in the I Ranch dairy had the highest concentrations of nutrients in storm runoff, and the highest loading rates and yields of ammonia and phosphorus. These tributaries account for only 10.3 percent of the area

  8. Sources and fate of sediment organic matter in Asia's largest brackish water lagoon and nearby mangrove ecosystem

    NASA Astrophysics Data System (ADS)

    Mukherjee, R.; Muduli, P. R.; Barik, S.; Kumar, S.

    2017-12-01

    Coastal lagoons and mangrove ecosystems regularly undergo natural (tidal) and anthropogenic (riverine inputs) forcings. After effects of these forcings cause coastal environments to sustain high biological production leading to high suspended organic matter (OM) and hence fast sedimentation and accumulation of OM in sediments.The different sources of OM and its burial in tropical lacustrine and mangrove systems have been rarely studied in detail with a few reports from Indian estuaries. The present study attempts to understand the sources and fate organic matter at two Ramsar sites, viz. Chilika Lake (Asia's largest brackish water lagoon) and nearby Bhitarkanika mangroves, located in the east coast of India. We measured nitrogen and carbon content (% N and % C) and isotopic composition (δ13Corg and δ15N) of OM at different depths in eight and three sediment cores collected from the Chilika lagoon and Bhitarkanika mangroves, respectively. Overall, the mean δ13Corg and % C in the lagoon were ‒21.10 ± 0.79 ‰ and 0.84 ± 0.47 %, respectively; whereas the same for mangrove cores were ‒24.56 ± 0.80 ‰ and 1.04 ± 0.26 %, respectively. Similarly, average δ15N and % N in the lagoon cores were 4.15 ± 0.63 ‰ and 0.11 ± 0.05 %, respectively; for mangrove cores the values were 4.28 ± 0.50 ‰ and 0.07 ± 0.01 %, respectively. Preliminary analysis of the isotopic composition (δ13Corg and δ15N) and elemental ratios indicates that organic carbon in the sediment at Bhitarkanika mangrove was of terrigenous, marine and in situ origin, whereas cores of Chilika lagoon showed predominantly marine signature. No relationship between δ13Corg of suspended and sediment in the Chilika lagoon indicates these two organic pools to be not directly coupled. End member mixing model in the mangrove ecosystem indicate on an average 50 % terrestrial contribution to the OM pool.

  9. Dynamics of pollution-indicator and heterotrophic bacteria in sewage treatment lagoons.

    PubMed Central

    Legendre, P; Baleux, B; Troussellier, M

    1984-01-01

    The spatio-temporal dynamics of pollution-indicator bacteria and aerobic heterotrophic bacteria were studied in the sewage treatment lagoons of an urban wastewater center after 26 months of biweekly sampling at eight stations in these lagoons. Robust statistical methods of time-series analysis were used to study successional steps (through chronological clustering) and rhythmic behavior through time (through contingency periodogram). The aerobic heterotrophic bacterial community showed two types of temporal evolution: in the first four stations, it seems mainly controlled by the nutrient support capacity of the sewage input, whereas in the remaining part of the lagoon, it seems likely that the pollution-indicator bacteria are gradually replaced by other bacterial types that are better adapted to this environment. On the other hand, the pollution-indicator bacteria showed an annual cycle which increased in amplitude at distances further from the wastewater source. The main events in this cycle were produced simultaneously at all stations, indicating control of these bacterial populations by climatic factors, which act through physical and chemical factors, and also through other biological components of this ecosystem (phytoplankton and zooplankton). Finally, we use results from this study to suggest a modified design for a future study program. Images PMID:6497372

  10. Morphometric or morpho-anatomal and genetic investigations highlight allopatric speciation in Western Mediterranean lagoons within the Atherina lagunae species (Teleostei, Atherinidae)

    NASA Astrophysics Data System (ADS)

    Trabelsi, M.; Maamouri, F.; Quignard, J.-P.; Boussaïd, M.; Faure, E.

    2004-12-01

    Current distribution of Atherina lagunae poses an interesting biogeographical problem as this species inhabits widely separate circum-Mediterranean lagoons. Statistical analyses of 87 biometric parameters and genetic variation in a portion of the cytochrome b gene were examined in four populations of A. lagunae from Tunisian and French lagoons. The results suggested a subdivision into two distinct Atherinid groups: one included the French lagoonal sand smelts and the second included the Tunisian ones. Tunisian lagoonal sand smelts were distinguished from the French ones by the lower number of lateral line scales, vertebrae, pectorals and first dorsal fin rays and the higher number of lower and total gillrakers. In addition, A. lagunae from Tunisian lagoons are characterised by short preorbital length, developed operculum, broad interorbital space, larger head, robust body and a relatively small first dorsal fin which is positioned backwards. In addition, intraspecific sequence variation in a portion of the cytochrome b gene was examined in 87 individuals from Tunisia and France. The high correlation between the results of the molecular phylogenetic tree and biometric statistical data analysis suggested that two different sibling species or at least sub-species or semi-species have colonised the lagoons. In addition, our analyses suggested that the evolution of A. lagunae probably occurred in two steps including marine sympatric speciation within the large Atherina boyeri complex and a post-Pleistocene colonisation of the lagoons.

  11. Eutrophication increases methane emission to the atmosphere in tropical lagoons: insights from two Ivory Coast sites

    NASA Astrophysics Data System (ADS)

    José-mathieu Koné, Yéfanlan; Vieira Borges, Alberto

    2017-04-01

    Eutrophication increases methane emission to the atmosphere in tropical lagoons: insights from two Ivory Coast sites. Y J M Koné (1) & A.V. Borges (2) (1) Centre de recherches océanologiques (CRO) d'Abidjan, (Ivory Coast) (2) University of Liège, Chemical Oceanography Unit, Liège, Belgium (Belgium) Eutrophication is a worldwide environmental problem and a definitive solution is far from being achieved, despite the large number of studies documenting its causes. In small aquatic ecosystems, excessive growth of macrophytes is a well known undesirable consequence of eutrophication. When these plants die and sink to the bottom the decomposing biomass depletes oxygen content in the water column thus leading to anoxia promoting methane (CH4) production. Here, we reported the CH4 data obtained during six campaigns covering the annual cycle in two small lagoons of Ivory Coast (Ono, Kodjoboué) that are contrasted in the degree of eutrophication and the corresponding coverage of macrophytes (e.g. Echinochloa pyramidalis, Eichhornia crassipes, Hydrilla verticillata). Our data showed a high spatio-temporal variability of CH4 within the lagoons and between the two systems, with CH4 concentrations in surface waters ranging between 80 to 74,604 nmol L-1. The highest CH4 concentration values were observed in the eutrophic Ono lagoon that is covered by 80% of macrophytes, suggesting that lagoons dominated by macrophytes are significant sources of CH4 toward the atmosphere.

  12. Investigation of residence time and groundwater flux in Venice Lagoon: comparing radium isotope and hydrodynamic models.

    PubMed

    Rapaglia, John; Ferrarin, Christian; Zaggia, Luca; Moore, Willard S; Umgiesser, Georg; Garcia-Solsona, Ester; Garcia-Orellana, Jordi; Masqué, Pere

    2010-07-01

    The four naturally-occurring isotopes of radium were coupled with a previously evaluated hydrodynamic model to determine the apparent age of surface waters and to quantify submarine groundwater discharge (SGD) into the Venice Lagoon, Italy. Mean apparent age of water in the Venice Lagoon was calculated using the ratio of 224Ra to 228Ra determined from 30 monitoring stations and a mean pore water end member. Average apparent age was calculated to be 6.0 d using Ra ratios. This calculated age was very similar to average residence time calculated for the same period using a hydrodynamic model (5.8 d). A mass balance of Ra was accomplished by quantifying each of the sources and sinks of Ra in the lagoon, with the unknown variable being attributed to SGD. Total SGD were calculated to be 4.1 +/- 1.5, 3.8 +/- 0.7, 3.0 +/- 1.3, and 3.5 +/- 1.0 x 10(10) L d(-1) for (223,224,226, 228)Ra, respectively, which are an order of magnitude larger than total mean fluvial discharge into the Venice Lagoon (3.1 x 10(9) L d(-1)). The SGD as a source of nutrients in the Venice Lagoon is also discussed and, though significant to the nutrient budget, is likely to be less important as the dominant control on SGD is recirculated seawater rather than freshwater. 2009 Elsevier Ltd. All rights reserved.

  13. Characterization and evolution of the sediments of a Mediterranean coastal lagoon located next to a former mining area.

    PubMed

    García, Gregorio; Muñoz-Vera, Ana

    2015-11-15

    Coastal lagoons are ecosystems that are relatively enclosed water bodies under the influence of both the terrestrial and the marine environment, being vulnerable to human impacts. Human activities, such as mining extraction, are significant anthropogenic coastal stressors that can negatively affect ecosystems and communities. In light of the above, the objective of this research is to examine the influence of metal mining activities on the composition of sediments of a Mediterranean coastal lagoon, named Mar Menor. This paper presents a comprehensive characterization for grain size, mineralogy, geochemistry and organic matter of sediments of this coastal lagoon, investigating their variation along space and time. Sedimentation dynamics are ruling clearly the grain size predominant in each area of the Mar Menor coastal lagoon, determining the existence of entrainment, transport and sedimentation areas. For minerals, elements and organic matter, sedimentation dynamics are also determining their distribution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Benthic foraminifera as bio-indicators of trace element pollution in the heavily contaminated Santa Gilla lagoon (Cagliari, Italy).

    PubMed

    Frontalini, Fabrizio; Buosi, Carla; Da Pelo, Stefania; Coccioni, Rodolfo; Cherchi, Antonietta; Bucci, Carla

    2009-06-01

    In order to assess the response of benthic foraminifera to trace element pollution, a study of benthic foraminiferal assemblages was carried out into sediment samples collected from the Santa Gilla lagoon (Sardinia, Italy). The lagoon has been contaminated by industrial waste, mainly trace elements, as well as by agricultural and domestic effluent. The analysis of surficial sediment shows enrichment in trace elements, including Cr, Cu, Hg, Ni, Pb and Zn. Biotic and abiotic data, analyzed with multivariate techniques of statistical analysis, reveal a distinct separation of both the highly polluted and less polluted sampling sites. The innermost part of the lagoon, comprising the industrial complex at Macchiareddu, is exposed to a high load of trace elements which are probably enhanced by their accumulation in the finer sediment fraction. This area reveals lower diversity and higher percentages of abnormalities when compared to the outermost part of the lagoon.

  15. Air breathing in Magadi tilapia Alcolapia grahami, under normoxic and hyperoxic conditions, and the association with sunlight and reactive oxygen species.

    PubMed

    Johannsson, O E; Bergman, H L; Wood, C M; Laurent, P; Kavembe, D G; Bianchini, A; Maina, J N; Chevalier, C; Bianchini, L F; Papah, M B; Ojoo, R O

    2014-03-01

    Observations of the Magadi tilapia Alcolapia grahami in hot, highly alkaline Lake Magadi revealed that they air breathe not only during hypoxia, as described previously, but also during normoxia and hyperoxia. Air breathing under these latter conditions occurred within distinct groupings of fish (pods) and involved only a small proportion of the population. Air breathing properties (duration and frequency) were quantified from video footage. Air breathing within the population followed a diel pattern with the maximum extent of pod formation occurring in early afternoon. High levels of reactive oxygen species (ROS) in the water may be an irritant that encourages the air-breathing behaviour. The diel pattern of air breathing in the field and in experiments followed the diel pattern of ROS concentrations in the water which are amongst the highest reported in the literature (maximum daytime values of 2.53 – 8.10 μM H₂O₂). Interlamellar cell masses (ILCM) occurred between the gill lamellae of fish from the lagoon with highest ROS and highest oxygen levels, while fish from a normoxic lagoon with one third the ROS had little or no ILCM. This is the first record of air breathing in a facultative air-breathing fish in hyperoxic conditions and the first record of an ILCM in a cichlid species. © 2013 The Fisheries Society of the British Isles.

  16. Influence of environmental variation on the bacterioplankton community and its loss to viral lysis in the Curonian Lagoon

    NASA Astrophysics Data System (ADS)

    Šulčius, Sigitas; Reunamo, Anna; Paškauskas, Ričardas; Leskinen, Piia

    2018-05-01

    Coastal lagoons are continuously exposed to strong environmental gradients that determine the distribution and trophic interactions of microbial communities. Therefore, in this study we assessed whether and how environmental changes influence the bacterial community and its vulnerability to viral infection and lysis along the major environmental gradient in the Curonian Lagoon. We found significant differences in bacterial community profiles, their richness and evenness between the riverine, freshwater southern part and the Baltic Sea water intrusion-influenced northern part of the lagoon, suggesting strong environmental control of the structure of bacterial communities. Viruses were found to be play an important role in bacterial mortality in the Curonian Lagoon, being responsible for the removal of 20-50% of the bacterial standing stock. We observed differences in virioplankton decay rates and virus burst sizes between the northern and southern parts of the lagoon. However, no relationships were found between viral activity and bacterial communities within the lagoon ecosystem. The frequency of infected cells and virus-mediated bacterial mortality (VMBM) remained constant among the sampling sites irrespective of differences in bacteria community assemblages and environmental conditions. The results indicate that factors determining changes in bacterial diversity are different from the factors limiting their vulnerability to viral infection and lysis. This study also suggests that under changing environmental conditions, virus-bacteria interactions are more stable than the interacting viral and bacterial communities themselves. These findings are important for understanding the functioning of the coastal ecosystems under the rapidly changing local (spatial and temporal) and global (e.g. eutrophication, climate change) conditions.

  17. A spatially resolved model of seasonal variations in phytoplankton and clam ( Tapes philippinarum) biomass in Barbamarco Lagoon, Italy

    NASA Astrophysics Data System (ADS)

    Spillman, C. M.; Hamilton, D. P.; Hipsey, M. R.; Imberger, J.

    2008-08-01

    Barbamarco Lagoon (area = 7 km 2) is in the Po River Delta, adjoining the Northern Adriatic Sea, and supports a commercially valuable clam ( Tapes philippinarum) fishery. This study investigated interactions of the lagoon with adjacent coastal waters and inland riverine inputs by modelling both the lagoon and the Northern Adriatic Sea, using a coupled three-dimensional (3D) hydrodynamic-ecological model (ELCOM-CAEDYM) adapted to include the clam population. The clam model accounted for carbon (C), nitrogen (N) and phosphorus (P) biomass in the benthos through parameterisations for filtration, excretion, egestion, respiration, mortality, and harvesting. Multiple clam size classes were included in a new population dynamics sub-model. Output from the coupled model was validated against hydrodynamic and water quality data from intensive field sampling and routine monitoring. Time scales of tidal flushing, primary production and clam grazing were investigated with the model to demonstrate that food supply to clam populations is dominated by phytoplankton inputs from the Northern Adriatic Sea. Effects of clam cultivation on nutrient concentrations and phytoplankton biomass in Barbamarco Lagoon were primarily localised, with strong tidal flushing minimising impacts of clam filtration on lagoon-wide nutrient concentrations at current clam stocking levels. Clam populations were found to alter the cycling of nutrients in the system, causing the lagoon to become a net sink for particulate organic matter and to export dissolved organic matter to the adjacent sea via tidal flushing. Ecosystem health and sensitivity of nutrient cycles to clam cultivation are important considerations for the long term sustainable management and potential expansion of the fishery.

  18. Environmental Quality Assessment of Bizerte Lagoon (Tunisia) Using Living Foraminifera Assemblages and a Multiproxy Approach.

    PubMed

    Alves Martins, Maria Virgínia; Zaaboub, Noureddine; Aleya, Lotfi; Frontalini, Fabrizio; Pereira, Egberto; Miranda, Paulo; Mane, Miguel; Rocha, Fernando; Laut, Lazaro; El Bour, Monia

    2015-01-01

    This study investigated the environmental quality of the Bizerte Lagoon (Tunisia) through an integrated approach that combined environmental, biogeochemical, and living benthic foraminiferal analyses. Specifically, we analyzed the physicochemical parameters of the water and sediment. The textural, mineralogical, and geochemical characteristics of the sediment, including total organic carbon, total nitrogen, simultaneously extracted metals (SEM), acid volatile sulfides (AVS), chlorophyll a, CaCO3, and changes in bacterial populations and carbon isotopes were measured. The SEM/AVS values indicated the presence of relatively high concentrations of toxic metals in only some areas. Foraminiferal assemblages were dominated by species such as A. parkinsoniana (20-91%), Bolivina striatula (<40%), Hopkinsina atlantica (<17%), and Bolivina ordinaria (<15%) that cannot be considered typical of impacted coastal lagoons both in Mediterranean and northeast Atlantic regions. The results of this work suggest that Bizerte Lagoon is a unique setting. This lagoon is populated by typical marine species that invaded this ecosystem, attracted not only by the prevailing favorable environmental conditions but also by the abundance and quality of food. The results indicate that the metal pollution found in some areas have a negative impact on the assemblages of foraminifera. At present, however, this negative impact is not highly alarming.

  19. Environmental Quality Assessment of Bizerte Lagoon (Tunisia) Using Living Foraminifera Assemblages and a Multiproxy Approach

    PubMed Central

    Alves Martins, Maria Virgínia; Zaaboub, Noureddine; Aleya, Lotfi; Frontalini, Fabrizio; Pereira, Egberto; Miranda, Paulo; Mane, Miguel; Rocha, Fernando; Laut, Lazaro; El Bour, Monia

    2015-01-01

    This study investigated the environmental quality of the Bizerte Lagoon (Tunisia) through an integrated approach that combined environmental, biogeochemical, and living benthic foraminiferal analyses. Specifically, we analyzed the physicochemical parameters of the water and sediment. The textural, mineralogical, and geochemical characteristics of the sediment, including total organic carbon, total nitrogen, simultaneously extracted metals (SEM), acid volatile sulfides (AVS), chlorophyll a, CaCO3, and changes in bacterial populations and carbon isotopes were measured. The SEM/AVS values indicated the presence of relatively high concentrations of toxic metals in only some areas. Foraminiferal assemblages were dominated by species such as A. parkinsoniana (20–91%), Bolivina striatula (<40%), Hopkinsina atlantica (<17%), and Bolivina ordinaria (<15%) that cannot be considered typical of impacted coastal lagoons both in Mediterranean and northeast Atlantic regions. The results of this work suggest that Bizerte Lagoon is a unique setting. This lagoon is populated by typical marine species that invaded this ecosystem, attracted not only by the prevailing favorable environmental conditions but also by the abundance and quality of food. The results indicate that the metal pollution found in some areas have a negative impact on the assemblages of foraminifera. At present, however, this negative impact is not highly alarming. PMID:26372655

  20. Water Hyacinths for Upgrading Sewage Lagoons to Meet Advanced Wastewater Treatment Standards, Part 1

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.

    1975-01-01

    Water hyacinths, Eichhornia crassipes Mart. Solms, have demonstrated the ability to function as an efficient and inexpensive final filtration system in a secondary domestic sewage lagoon during a three month test period. These plants reduced the suspended solids, biochemical oxygen demanding substances, and other chemical parameters to levels below the standards set by the state pollution control agency. The water hyacinth-covered secondary lagoon utilized in this experiment had a surface area of 0.28 hectare (0.70 acre) with a total capacity of 6.8 million liters (1.5 million gallons), receiving an inflow of 522,100 liters (115,000 gallons) per day from a 1.1 hectare (3.8 acre) aerated primary sewage lagoon. These conditions allowed a retention time of 14 to 21 days depending on the water hyacinth evapotranspiration rates. The desired purity of final sewage effluent can be controlled by the water hyacinth surface area, harvest rate, and the retention time.

  1. ANALYSIS OF SWINE LAGOONS AND GROUND WATER FOR ENVIRONMENTAL ESTROGENS

    EPA Science Inventory

    A method was developed for analysis of low levels of natural (estradiol, estrone, estriol) and synthetic (ethynylestradiol) estrogens in ground water and swine waste lagoon effluent. The method includes solid phase extraction of the estrogens, preparation of pentafluorobenzyl der...

  2. Quantifying groundwater exchange rates in a beach barrier lagoon using a radioisotopic tracer and geophysical methods: Younger Lagoon, Santa Cruz, CA

    NASA Astrophysics Data System (ADS)

    Richardson, C. M.; Swarzenski, P. W.; Johnson, C.

    2013-12-01

    Coastal lagoons are highly productive systems with a strong dependence on the physico-chemical regime of their surrounding environment. Groundwater interactions with the nearshore environment can drive ecosystem stability and productivity. Lagoons with restricted surface connectivity interact with coastal waters via subsurface flow paths that follow natural hydraulic gradients, producing a dynamic freshwater-saltwater mixing zone with submarine groundwater discharge (SGD) regions that are tidally influenced. Recent studies demonstrate the importance of SGD in maintaining nearshore ecology through a number of processes, including enhanced chemical loadings, focused biogeochemical transformations, and complex water mixing scenarios (Slomp and Van Cappellen, 2004 and Taniguchi et al., 2002). Groundwater discharge to the coastal ocean is often slow, diffuse and site-specific. Traditional methods used to evaluate SGD fluxes operate at varying scales and typically result in over or underestimates of SGD. Novel monitoring and evaluation methods are required in order to better understand how coastal aquifer systems influence multi-scalar water and nutrient budgets. Recently developed methods to determine fluid exchange rates include the use of select U- and Th-series radionuclides, multi-channel resistivity imaging, as well as the integration of temperature data and 1-D analytical modeling. Groundwater fluxes were examined in a coastal lagoon system to characterize the physics of subsurface fluid transport evidenced by visible seepage faces at low tide. Fluid exchange rates were quantified to determine the spatial and temporal variability of groundwater movement using thermal time series, water level data, and a coupled radiotracer-geophysical method. Our investigation of subsurface characteristics and groundwater fluxes using both traditional and newly-developed methods indicated that seasonal water inputs and tidal controls on water table elevation significantly

  3. SUPERFUND TREATABILITY CLEARINGHOUSE: FINAL REPORT: DEVELOPMENT OF OPTIMUM TREATMENT SYSTEM FOR WASTEWATER LAGOONS PHASE II - SOLVENT EXTRACTION LABORATORY TESTING

    EPA Science Inventory

    The U.S. Army surveyed innovative treatment techniques for restoration of hazardous waste lagoons and selected solvent extraction as cost-effective restoration for further study. This treatability study focuses on treatment of organic (explosive) contaminated lagoon sediments w...

  4. ANALYSIS OF SWINE LAGOONS AND GROUND WATER FOR ENVIRONMENTAL ESTROGENS

    EPA Science Inventory

    A method was developed for analysis of low levels of natural (estradiol, estrone, estriol) and synthetic (ethinyl estradiol) estrogens in ground water and swine waste lagoon effluent. The method includes solid phase extraction of the estrogens, preparation of pentafluorobenzyl de...

  5. NPDES Permit for Lame Deer Lagoon Wastewater Treatment Facility in Montana

    EPA Pesticide Factsheets

    Final permit authorizes the Northern Cheyenne Utilities Commission to discharge from its Lame Deer Lagoon wastewater treatment facility located in Rosebud County, Montana to Lame Deer Creek, a tributary to Rosebud Creek.

  6. Fate of estradiol and testosterone in anaerobic lagoon digestors

    USDA-ARS?s Scientific Manuscript database

    Laboratory-scale lagoon digestors were constructed, and the fate of 14C-labelled 17ß-estradiol (E2) and testosterone (Test) were monitored for 42 d anaerobically under biological and sterile conditions. Hormone levels decreased in the liquid layer and increased in the sludge with time. At 42 d, 16-2...

  7. Seahorse (Hippocampinae) population fluctuations in the Ria Formosa Lagoon, south Portugal.

    PubMed

    Correia, M; Caldwell, I R; Koldewey, H J; Andrade, J P; Palma, J

    2015-09-01

    Comparisons of three sets of surveys in the Ria Formosa Lagoon, Portugal, over a 13 year period (2001-2002, 2008-2009 and 2010-2013) revealed significant population fluctuations in at least one of the two seahorse (Hippocampinae) species living there, and that those fluctuations were potentially associated with habitat changes in the lagoon. After a significant decline between the first two survey periods (2001-2002 v. 2008-2009), long-snouted seahorse Hippocampus guttulatus populations increased significantly between 2008-2009 surveys and new 2010-2013 surveys. There were no significant differences in H. guttulatus populations between the 2001-2002 and 2010-2013 surveys. In contrast, there were no significant differences in short-snouted seahorse Hippocampus hippocampus densities among the 16 sites surveyed throughout the three sampling periods, although the ability to detect any change was hampered by the low densities of this species in all time periods. Fluctuations in H. guttulatus densities were positively correlated with the percentage of holdfast coverage, but with none of the other environmental variables tested. These results highlight the importance of holdfast availability in maintaining stable seahorse populations. While population fluctuations are certainly more promising than a consistent downward decline, such extreme fluctuations observed for seahorses in the Ria Formosa Lagoon could still leave these two species vulnerable to any additional stressors, particularly during low density periods. © 2015 The Fisheries Society of the British Isles.

  8. Masterplan to safeguard Venice and to restore the lagoon and conterminous areas

    NASA Astrophysics Data System (ADS)

    Bini, Claudio; Gallo, Alba; Nadimi-Goki, Mandana; Wahsha, Mohammad

    2015-04-01

    Venice and its lagoon constitute a complex system, well known all over the world for the peculiarity of the town and for the fragility of the lagoon ecosystem with its delicate equilibrium. The whole system has been, and is currently, affected by human activities (industry, agriculture, settlements, tourism) that impact severely the ecosystem. Discharge from the agricultural drainage basin affects particularly the area North of the city of Venice; the central and southern areas, instead, receive important pollutant inputs from the industrial zone of Porto Marghera since the early'50s. Additional sources of pollution are domestic sewage and waste disposal from the urban area, that is visited by more than 10M people every year. As a consequence of the increasing land contamination, significant amounts of contaminants (both organic and inorganic) are accumulated in soils of the borderline, in water and in lagoon sediments, which constitute a potential source of secondary pollution. Results of surveys carried out in recent years in the whole area show that contaminants concentration increased from the beginning of the industrial activities until the '90s, when Porto Marghera declined. Most of contaminants have concentrations above the background levels. The highest metal levels were found in an area between Porto Marghera and the city of Venice, where both industrial and urban sewage are discharged, provoking environmental and human health hazard. In order to safeguard the city of Venice, and to restore its lagoon and conterminous areas, a Master Plan of intervention has been developed since the early 2000s. The land currently interested by environmental analysis and/or restoration covers approximately 1350ha; 78% of these (1100ha) proved variously contaminated, with 85% of sites overcoming the National Reference Values. Contamination, besides being diffused, is quite complex, involving the co-existence of several contaminant families (PAH, PCB, dioxin, heavy metals

  9. Silica in invasive wetland plant species of lagoons, Côte d'Ivoire: Spatio-temporal patterns

    NASA Astrophysics Data System (ADS)

    José-mathieu Koné, Yéfanlan; Schoelynck, Jonas

    2017-04-01

    Tropical wetlands are known to accumulate a large quantity of Biogenic Silica (BSi) produced by wetland plant species (Struyf et al., 2015), and approximately 70-80% of the total supply of Dissolved Si (DSi) to the coastal zone occurs in (sub) tropical river systems (Jennerjahn et al. 2006). However, the data at these latitudes are limited. Here, we present the BSi concentration from eleven invasive macrophyte species randomly collected in three small ( 800ha) lagoons of Côte d'Ivoire during 12 months. Our data showed a large spatio-temporal variability of BSi in the three lagoons with no consistent trends. In general, the BSi concentrations obtained were high and values ranged from 0 to 54 mg g-1 through the entire sampling period, with the highest values found in Acroceras zizaniodes (emergent species of Poaceae). In general, free floating species had significantly less BSi than emergent species (P<0.0001) which corroborates with the earlier findings of Schoelynck and Struyf (2016). However, the concentrations of BSi found in Salvinia molesta (a free floating species of fern, Salviniaceae) at the young stage were similar to those found in the emergent species. Based on yearly averages, highest BSi values were observed in Kodjoboué lagoon, and the lowest in the Ono lagoon that is 80% covered by macrophytes. Moreover, the dissolved silica (DSi) concentrations were systematically higher in Ono Lagoon than in Kodjoboué Lagoon. We conclude that in an eutrophic system Si accumulating in aquatic macrophytes is not related to Si availability but to other environmental factors. Jennerjahn, T.C., Knoppers, B.A., de Souze, W.F.L., Brunskill, G.J., Silva, E.I.L., Adi, S. et al., 2006. Factors controlling dissolved silica in tropical rivers. In: Ittekot, V. (ed) The silicon cycle. Island Press, Washington, D. C, pp 29-51 Schoelynck J and Struyf E, 2016. Silicon in aquatic vegetation. Functional Ecology. 30: 1323-1330. Struyf, E., Mosimane, K., Van Pelt, D., Murray

  10. Experimental evidence of nitrogen control on pCO(2) in phosphorus-enriched humic and clear coastal lagoon waters.

    PubMed

    Peixoto, Roberta B; Marotta, Humberto; Enrich-Prast, Alex

    2013-01-01

    Natural and human-induced controls on carbon dioxide (CO(2)) in tropical waters may be very dynamic (over time and among or within ecosystems) considering the potential role of warmer temperatures intensifying metabolic responses and playing a direct role on the balance between photosynthesis and respiration. The high magnitude of biological processes at low latitudes following eutrophication by nitrogen (N) and phosphorus (P) inputs into coastal lagoons waters may be a relevant component of the carbon cycle, showing controls on partial pressure of CO(2) (pCO(2)) that are still poorly understood. Here we assessed the strength of N control on pCO(2) in P-enriched humic and clear coastal lagoons waters, using four experimental treatments in microcosms: control (no additional nutrients) and three levels of N additions coupled to P enrichments. In humic coastal lagoons waters, a persistent CO(2) supersaturation was reported in controls and all nutrient-enriched treatments, ranging from 24- to 4-fold the atmospheric equilibrium value. However, both humic and clear coastal lagoons waters only showed significant decreases in pCO(2) in relation to the controlled microcosms in the two treatments with higher N addition levels. Additionally, clear coastal lagoons water microcosms showed a shift from CO(2) sources to CO(2) sinks, in relation to the atmosphere. Only in the two more N-enriched treatments did pCO(2) substantially decrease, from 650 µatm in controls and less N-enriched treatments to 10 µatm in more N-enriched microcosms. Humic substrates and N inputs can modulate pCO(2) even in P-enriched coastal lagoons waters, thereby being important drivers on CO(2) outgassing from inland waters.

  11. Experimental evidence of nitrogen control on pCO2 in phosphorus-enriched humic and clear coastal lagoon waters

    PubMed Central

    Peixoto, Roberta B.; Marotta, Humberto; Enrich-Prast, Alex

    2013-01-01

    Natural and human-induced controls on carbon dioxide (CO2) in tropical waters may be very dynamic (over time and among or within ecosystems) considering the potential role of warmer temperatures intensifying metabolic responses and playing a direct role on the balance between photosynthesis and respiration. The high magnitude of biological processes at low latitudes following eutrophication by nitrogen (N) and phosphorus (P) inputs into coastal lagoons waters may be a relevant component of the carbon cycle, showing controls on partial pressure of CO2 (pCO2) that are still poorly understood. Here we assessed the strength of N control on pCO2 in P-enriched humic and clear coastal lagoons waters, using four experimental treatments in microcosms: control (no additional nutrients) and three levels of N additions coupled to P enrichments. In humic coastal lagoons waters, a persistent CO2 supersaturation was reported in controls and all nutrient-enriched treatments, ranging from 24- to 4-fold the atmospheric equilibrium value. However, both humic and clear coastal lagoons waters only showed significant decreases in pCO2 in relation to the controlled microcosms in the two treatments with higher N addition levels. Additionally, clear coastal lagoons water microcosms showed a shift from CO2 sources to CO2 sinks, in relation to the atmosphere. Only in the two more N-enriched treatments did pCO2 substantially decrease, from 650 µatm in controls and less N-enriched treatments to 10 µatm in more N-enriched microcosms. Humic substrates and N inputs can modulate pCO2 even in P-enriched coastal lagoons waters, thereby being important drivers on CO2 outgassing from inland waters. PMID:23390422

  12. Recent carbonate firm- to hardgrounds in the Abu Dhabi lagoon: Environmental controls and petrography

    NASA Astrophysics Data System (ADS)

    Immenhauser, Adrian; Lokier, Stephen W.; Kwiecien, Ola; Riechelmann, Sylvia; Buhl, Dieter

    2017-04-01

    Marine carbonate firm- and hardgrounds have been described from the Precambrian to the recent sedimentary archive. In comparison to the numerous publications dealing with fossil case examples, well-constrained studies of shoalwater hardground formation from modern (sub)tropical seas are comparably scarce. This comes as a surprise as only modern depositional environments offer direct insight into the plethora of environmental, geochemical, kinetic, and biological parameters that affect these features at formation and during diagenetic pathways. Here, we present the first results of a combined field and laboratory study with focus on firm- to hardgrounds (also termed "discontinuity" in the sense of a catch-it-all term) forming both in the shallow inner lagoon and the outer lagoon ooid shoals of the Abu Dhabi barrier-island complex. Essentially, the discontinuities found represent sub-grounds in the sense that they form a few centimetres beneath the sediment surface. Sub-grounds in the outer lagoon ooid shoals are cemented by characteristic needle-shaped aragonite crystals and essentially represent lithified crab burrows. In contrast, sub-grounds in the inner lagoon of Abu Dhabi form brittle intervals, perhaps 5 cm in thickness, that are cemented by platy aragonitic crystals that show uncommon morphologies. Botryoids are abundant and generally seem to affect crystal morphologies. First evidence suggests that these features form below the uppermost oxic layer of pore fluids in the shallow sedimentary column. These findings are placed in context with temporally-resolved data on sea and porewater chemistry.

  13. LAGOON WATER FROM CONFINED ANIMAL FEED OPERATIONS AND AMPHIBIAN DEVELOPMENT

    EPA Science Inventory


    Lagoon Water from Confined Animal Feed Operations and Amphibian Development. Dumont, J. N.* and Slagle, S., Oklahoma State University, Stillwater, OK, and Hutchins, S. R., U.S. Environmental Protection Agency (NRMRL/SPRD), Ada, OK. There is some evidence that confined anima...

  14. Use of respondent driven sampling (RDS) generates a very diverse sample of men who have sex with men (MSM) in Buenos Aires, Argentina.

    PubMed

    Carballo-Diéguez, Alex; Balan, Ivan; Marone, Rubén; Pando, María A; Dolezal, Curtis; Barreda, Victoria; Leu, Cheng-Shiun; Avila, María Mercedes

    2011-01-01

    Prior research focusing on men who have sex with men (MSM) conducted in Buenos Aires, Argentina, used convenience samples that included mainly gay identified men. To increase MSM sample representativeness, we used Respondent Driven Sampling (RDS) for the first time in Argentina. Using RDS, under certain specified conditions, the observed estimates for the percentage of the population with a specific trait are asymptotically unbiased. We describe, the diversity of the recruited sample, from the point of view of sexual orientation, and contrast the different subgroups in terms of their HIV sexual risk behavior. 500 MSM were recruited using RDS. Behavioral data were collected through face-to-face interviews and Web-based CASI. In contrast with prior studies, RDS generated a very diverse sample of MSM from a sexual identity perspective. Only 24.5% of participants identified as gay; 36.2% identified as bisexual, 21.9% as heterosexual, and 17.4% were grouped as "other." Gay and non-gay identified MSM differed significantly in their sexual behavior, the former having higher numbers of partners, more frequent sexual contacts and less frequency of condom use. One third of the men (gay, 3%; bisexual, 34%, heterosexual, 51%; other, 49%) reported having had sex with men, women and transvestites in the two months prior to the interview. This population requires further study and, potentially, HIV prevention strategies tailored to such diversity of partnerships. Our results highlight the potential effectiveness of using RDS to reach non-gay identified MSM. They also present lessons learned in the implementation of RDS to recruit MSM concerning both the importance and limitations of formative work, the need to tailor incentives to circumstances of the less affluent potential participants, the need to prevent masking, and the challenge of assessing network size.

  15. Use of Respondent Driven Sampling (RDS) Generates a Very Diverse Sample of Men Who Have Sex with Men (MSM) in Buenos Aires, Argentina

    PubMed Central

    Carballo-Diéguez, Alex; Balan, Ivan; Marone, Rubén; Pando, María A.; Dolezal, Curtis; Barreda, Victoria; Leu, Cheng-Shiun; Ávila, María Mercedes

    2011-01-01

    Background Prior research focusing on men who have sex with men (MSM) conducted in Buenos Aires, Argentina, used convenience samples that included mainly gay identified men. To increase MSM sample representativeness, we used Respondent Driven Sampling (RDS) for the first time in Argentina. Using RDS, under certain specified conditions, the observed estimates for the percentage of the population with a specific trait are asymptotically unbiased. We describe, the diversity of the recruited sample, from the point of view of sexual orientation, and contrast the different subgroups in terms of their HIV sexual risk behavior. Methodology 500 MSM were recruited using RDS. Behavioral data were collected through face-to-face interviews and Web-based CASI. Conclusion In contrast with prior studies, RDS generated a very diverse sample of MSM from a sexual identity perspective. Only 24.5% of participants identified as gay; 36.2% identified as bisexual, 21.9% as heterosexual, and 17.4% were grouped as “other.” Gay and non-gay identified MSM differed significantly in their sexual behavior, the former having higher numbers of partners, more frequent sexual contacts and less frequency of condom use. One third of the men (gay, 3%; bisexual, 34%, heterosexual, 51%; other, 49%) reported having had sex with men, women and transvestites in the two months prior to the interview. This population requires further study and, potentially, HIV prevention strategies tailored to such diversity of partnerships. Our results highlight the potential effectiveness of using RDS to reach non-gay identified MSM. They also present lessons learned in the implementation of RDS to recruit MSM concerning both the importance and limitations of formative work, the need to tailor incentives to circumstances of the less affluent potential participants, the need to prevent masking, and the challenge of assessing network size. PMID:22102896

  16. The Challenge of High-resolution Mapping of Very Shallow Coastal Areas: Case Study of the Lagoon of Venice, Italy

    NASA Astrophysics Data System (ADS)

    Madricardo, F.; Foglini, F.; Kruss, A.; Bajo, M.; Campiani, E.; Ferrarin, C.; Fogarin, S.; Grande, V.; Janowski, L.; Keppel, E.; Leidi, E.; Lorenzetti, G.; Maicu, F.; Maselli, V.; Montereale Gavazzi, G.; Pellegrini, C.; Petrizzo, A.; Prampolini, M.; Remia, A.; Rizzetto, F.; Rovere, M.; Sarretta, A.; Sigovini, M.; Toso, C.; Zaggia, L.; Trincardi, F.

    2017-12-01

    Very shallow coastal environments are often highly urbanized with half of the world's population and 13 of the largest mega-cities located close to the coast. These environments undergo rapid morphological changes due to natural and anthropogenic pressure that will likely be enhanced in the near future by mean sea-level rise. Therefore, there is a strong need for high resolution seafloor mapping to monitor and protect shallow coastal areas. To date, only about 5% of their seafloor has been mapped: their shallowness has prevented so far the use of underwater acoustics to reveal their morphological features; their turbidity often hindered the efficient use of LIDAR technology, particularly in lagoons and estuaries. The recent technological development of multibeam echosounder systems, however, enables these instruments to achieve very high performances also in such shallow environments. In this work, we present the results of an extensive multibeam survey carried out in the Lagoon of Venice (Italy) in 2013. The Lagoon of Venice is the biggest lagoon in the Mediterranean Sea (surface area of about 550 km2, average depth of about 1 m) and it is a UNESCO World Cultural and Natural Heritage site together with the historical city of Venice which is currently endangered by relative sea-level rise. Major engineering works are ongoing at the lagoon inlets (MOSE project) to protect Venice from flood events. In the last century, the morphology and ecology of the lagoon changed dramatically: the extent of the salt marshes was reduced by 60% and some parts of the lagoon deepened by more than 1 m with a net sediment flux exiting from the inlets. To understand and monitor the future evolution of the Lagoon of Venice in view of the inlet modifications and mean sea-level rise, CNR-ISMAR within the project RITMARE (a National Research Programme funded by the Italian Ministry of University and Research) carried out an extensive survey, involving a team of more than 25 scientists, to

  17. Surface water-groundwater exchange in transitional coastal environments by airborne electromagnetics: The Venice Lagoon example

    NASA Astrophysics Data System (ADS)

    Viezzoli, A.; Tosi, L.; Teatini, P.; Silvestri, S.

    2010-01-01

    A comprehensive investigation of the mixing between salt/fresh surficial water and groundwater in transitional environments is an issue of paramount importance considering the ecological, cultural, and socio-economic relevance of coastal zones. Acquiring information, which can improve the process understanding, is often logistically challenging, and generally expensive and slow in these areas. Here we investigate the capability of airborne electromagnetics (AEM) at the margin of the Venice Lagoon, Italy. The quasi-3D interpretation of the AEM outcome by the spatially constrained inversion (SCI) methodology allows us to accurately distinguish several hydrogeological features down to a depth of about 200 m. For example, the extent of the saltwater intrusion in coastal aquifers and the transition between the upper salt saturated and the underlying fresher sediments below the lagoon bottom are detected. The research highlights the AEM capability to improve the hydrogeological characterization of subsurface processes in worldwide lagoons, wetlands, deltas.

  18. Mercury in the sediments of the Marano and Grado Lagoon (northern Adriatic Sea): Sources, distribution and speciation

    NASA Astrophysics Data System (ADS)

    Acquavita, Alessandro; Covelli, Stefano; Emili, Andrea; Berto, Daniela; Faganeli, Jadran; Giani, Michele; Horvat, Milena; Koron, Neža; Rampazzo, Federico

    2012-11-01

    The existence of mining tailings in Idrija (Slovenia) and their subsequent transportation via the Isonzo River has been the primary source of mercury (Hg) in the northern Adriatic Sea for almost 500 years, making the Gulf of Trieste and the adjacent Marano and Grado Lagoon two of the most contaminated marine areas in the world. A further, more recent, contribution of Hg has been added by the operation of a chlor-alkali plant (CAP) located in the drainage basin flowing into the Lagoon. On the basis of previous research, as well as new data obtained from the "MIRACLE" project (Mercury Interdisciplinary Research for Appropriate Clam farming in a Lagoon Environment), the spatial distribution of Hg and its relationships with methylmercury (MeHg), organic matter and several geochemical parameters in surface sediments were investigated. The predominant and long-term impacts of the cinnabar-rich Isonzo River particulate matter in the Lagoon surface sediments are evident and confirmed by a decreasing concentration gradient from east (>11 μg g-1) to west (0.7 μg g-1). Hg originated from the CAP is only significant in the central sector of the Lagoon. Hg is primarily associated with fine-grained sediments (<16 μm), as a consequence of transport and dispersion from the fluvial source through littoral and tidal currents. However, speciation analyses highlighted the presence of Hg sulphides in the coarse sandy fraction of sediments from the eastern area, as expected given the origin of the sedimentary material. Unlike Hg, the distribution of MeHg (0.47-7.85 ng g-1) does not show a clear trend. MeHg constitutes, on average, 0.08% of total Hg and percentages are comparable to those obtained in similar lagoon environments. Higher MeHg concentrations in low to intermediate Hg-contaminated sediments indicate that the metal availability is not a limiting factor for MeHg occurrence, thus suggesting a major role played by environmental conditions and/or speciation. The reasonably

  19. Digging navigable waterways through lagoon tidal flats: which short and long-term impacts on groundwater dynamics and quality?

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Isotton, Giovanni; Nardean, Stefano; Ferronato, Massimiliano; Tosi, Luigi; Da Lio, Cristina; Zaggia, Luca; Bellafiore, Debora; Zecchin, Massimo; Baradello, Luca; Corami, Fabiana; Libralato, Giovanni; Morabito, Elisa; Broglia, Riccardo; Zaghi, Stefano

    2017-04-01

    Coastal lagoons are highly valued ephemeral habitats that have experienced in many cases the pressure of human activities since the development of urbanisation and economic activities within or around their boundaries. One typical intervention is dredging of canals to increase the exchange of water with the sea or for navigation purposes. In order to divert the route of large cruise liners from the historic center of Venice, Italy, the Venice Port Authority has recently proposed a project for the dredging of a new 3-km long and 10-m deep navigation canal (called Marghera-Venice Canal, MVC, in the sequel) through the shallows of the Venice Lagoon. The MVC will connect the passenger terminal located in the southwestern part of the historic center to a main channel that reaches the industrial area on the western lagoon margin. Can the new MVC facilitate saltwater intrusion below the lagoon bottom? Can the release into the lagoon of the chemicals detected in the groundwater around the industrial site be favoured by the MVC excavation? Can the depression waves generated by the ship transit (known as ship-wakes) along the MVC affect the flow and contaminant exchange between the subsurface and surficial systems? A response to these questions has been provided by the use of uncoupled and coupled density-dependent groundwater flow and transport simulators. The hydrogeological modelling has been supported by an in-depth characterization of the Venice lagoon subsurface along the MVC. Geophysical surveys, laboratory analyses on groundwater and sediment samples, in-situ measurements through piezometers and pressure sensors, and the outcome of 3D hydrodynamic and computational fluid dynamic (CFD) models have been used to set-up and calibrate the subsurface multi-model approach. The modelling results can be summarized as follows: i) the MVC has a negligible effect in relation to the propagation of the tidal regime into the subsoil; ii) the depression caused by the ship transit

  20. The sediments of the Venice Lagoon (Italy) evaluated in a screening risk assessment approach: part I--application of international sediment quality guidelines.

    PubMed

    Apitz, Sabine E; Barbanti, Andrea; Bocci, Martina; Carlin, Anna; Montobbio, Laura; Bernstein, Alberto Giulio

    2007-07-01

    A number of studies carried out in recent years have shown the presence of a wide range of contaminants in the Venice Lagoon. It is important to have a good understanding of the ecological quality of Venice Lagoon sediments in order to 1) define and locate areas where a threat to the environment is present and therefore an intervention is needed (i.e., in situ assessment and management); and 2) define sustainable and environmentally correct ways of managing sediments that are to be dredged for navigational purposes or in relation to other interventions (i.e., ex situ management). This study reports on a critical comparison of chemical quality of sediments in Venice Lagoon and its subregions. Data on the Venice Lagoon were compiled from several studies conducted during the past decade on surface sediment contamination; temporal variation and risks for contaminants at depth were not addressed. The comparison of observed pollutant concentrations with local and internationally used sediment quality guidelines (SQGs) was used as a tool to benchmark different sites and for a tier I (screening) ecological risk assessment. Meaning and relevance of a number of SQGs are discussed, together with the options available for carrying out the comparison with sediment data. The screening of the Venice Lagoon sediment quality is discussed from a risk-assessment perspective and appropriate values for use in an in situ-ex situ management framework are suggested. Although there were some differences depending upon which specific SQGs were applied, different SQGs provided the same general picture of screening risk in Venice Lagoon: Although there are geographic differences, median levels for several contaminants in surface sediments exceeded a number of SQGs. Many contaminants exceed threshold effects SQGs, and Hg exceeds probable effects SQGs in most sub-basins except the southern Lagoon. Venice Lagoon south has the lowest screening risk levels, Venice Lagoon central/north has the

  1. Sedimentation rate and lateral migration of tidal channels in the Lagoon of Venice (Northern Italy)

    NASA Astrophysics Data System (ADS)

    Donnici, Sandra; Madricardo, Fantina; Serandrei-Barbero, Rossana

    2017-11-01

    Tidal channels are crucial for the functioning of highly valuable coastal environments, such as estuaries and lagoons. Their properties, however, are currently less understood than those of river systems. To elucidate their past behaviour, an extensive geophysical investigation was performed to reconstruct the evolution of channels and tidal surfaces in the central part of the Lagoon of Venice (Italy) over the past 5000 years. Comparing high-spatial-resolution acoustic data and sedimentary facies analyses of 41 cores, 29 of which were radiocarbon dated, revealed the sedimentation rates in different lagoonal environments and allowed the migration of two large meanders to be reconstructed. The average sedimentation rate of the study succession in the different sedimentary environments was 1.27 mm yr-1. The lateral migration rates were 13-23 m/century. This estimate is consistent with the lateral migration rates determined by comparing aerial photographs of recent channels. Comparing the buried channels with historical and current maps showed that, in general, the number of active channels is now reduced. Their morphology was sometimes simplified by artificial interventions. An understanding of the impact of the artificial interventions over time is useful for the management and conservation of tidal environments, particularly for the Lagoon of Venice, where management authorities are currently debating the possible deepening and rectification of large navigation channels.

  2. International Symposium on Coastal Lagoons. (Bordeaux, France, September 8-14, 1981). Unesco Technical Papers in Marine Science 43.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Marine Sciences.

    Lagoons and their characteristic coastal bay-mouth bars represent 15 percent of the world coastal zone. They are among the most productive ecosystems in the biosphere, this productivity resulting from the interplay of ocean and continent. An International Symposium on Coastal Lagoons (ISCOL) was held to: assess the state of knowledge in the…

  3. Prokaryotic diversity in one of the largest hypersaline coastal lagoons in the world.

    PubMed

    Clementino, M M; Vieira, R P; Cardoso, A M; Nascimento, A P A; Silveira, C B; Riva, T C; Gonzalez, A S M; Paranhos, R; Albano, R M; Ventosa, A; Martins, O B

    2008-07-01

    Araruama Lagoon is an environment characterized by high salt concentrations. The low raining and high evaporation rates in this region favored the development of many salty ponds around the lagoon. In order to reveal the microbial composition of this system, we performed a 16S rRNA gene survey. Among archaea, most clones were related to uncultured environmental Euryarchaeota. In lagoon water, we found some clones related to Methanomicrobia and Methanothermococcus groups, while in the saline pond water members related to the genus Haloarcula were detected. Bacterial community was dominated by clones related to Gamma-proteobacteria, Actinobacteria, and Synechococcus in lagoon water, while Salinibacter ruber relatives dominated in saline pond. We also detected the presence of Alpha-proteobacteria, Pseudomonas-like bacteria and Verrucomicrobia. Only representatives of the genus Ralstonia were cosmopolitan, being observed in both systems. The detection of a substantial number of clones related to uncultured archaea and bacteria suggest that the hypersaline waters of Araruama harbor a pool of novel prokaryotic phylotypes, distinct from those observed in other similar systems. We also observed clones related to halophilic genera of cyanobacteria that are specific for each habitat studied. Additionally, two bacterioplankton molecular markers with ecological relevance were analyzed, one is linked to nitrogen fixation (nifH) and the other is linked to carbon fixation by bacterial photosynthesis, the protochlorophyllide genes, revealing a specific genetic distribution in this ecosystem. This is the first study of the biogeography and community structure of microbial assemblages in Brazilian tropical hypersaline environments. This work is directed towards a better understanding of the free-living prokaryotic diversity adapted to life in hypersaline waters.

  4. Epiphyte communities on Thalassia testudinum from Grand Cayman, British West Indies: Their composition, structure, and contribution to lagoonal sediments

    NASA Astrophysics Data System (ADS)

    Corlett, Hilary; Jones, Brian

    2007-02-01

    Thalassia testudinum, the most common seagrass found in lagoons around Grand Cayman, influences sedimentation by baffling currents, binding sediment on the seafloor, and providing substrates for a diverse epiphytic biota. About 85% of the epiphytic biota is formed of at least 3 species of coralline algae, 72 species of foraminifera, and 61 species of diatoms. The rest of the biota is formed of sponges, gastropods, ostracods, coccoliths, dinoflagellates, brown algae, and worms. The epiphytes are organized in three communities that are part of an organized tripartite community succession. The basal diatom community is overlain by the coralline algae community, which is then overlain by a community composed of a variety of taxa. The coralline algae community, which is the most extensive, typically covers ˜ 75% of the leaf's surface. Potentially, the skeletons of these epiphytes can make a significant contribution to the fine-grained sediment budget of these lagoons. Surprisingly, only a few of the epiphytes were found in the lagoonal sediment. It appears, therefore, that the epiphytes are lost through skeletal dissolution or transported out of the lagoon following storms. Irrespective of the cause, the epiphytes do not form a significant part of the lagoon sediment in Grand Cayman.

  5. A Field Study Training Program on Wastewater Lagoon Systems.

    ERIC Educational Resources Information Center

    Water and Wastewater Technical School, Neosho, MO.

    This publication is a text and reference manual for operating personnel of both large and small wastewater lagoon systems with support from the Environmental Protection Agency (EPA). As a text, this inservice training manual is intended to be used in a correspondence course wherein the trainee or operator would read and study each chapter before…

  6. The Role of Terrestrial Inputs of Organic Matter in Arctic Lagoons: Comparative Studies from Open-Water and Ice-Covered Periods

    NASA Astrophysics Data System (ADS)

    Dunton, K. H.; McClelland, J. W.; Connelly, T.; Linn, S.; Khosh, M.

    2012-12-01

    Coastal ecosystems of the Arctic receive extraordinarily large quantities of terrestrial organic matter through river discharge and shoreline erosion. This organic matter, both in dissolved and particulate form, may provide an important carbon and energy subsidy that supports and maintains heterotrophic activity and food webs in coastal waters, especially in the lagoons. Recent food web studies using stable isotopes confirm the significant assimilation of terrestrial organic matter, based on the depletion in both 13C and 15N content of invertebrate and vertebrate consumers collected in eastern Beaufort Sea lagoons vs. offshore waters. Our current work specifically focuses on a set of 12 field sites along the eastern Alaskan Beaufort Sea coast, from Barter Island to Demarcation Bay. To examine linkages between biological communities and organic matter inputs from land, we compared sites ranging from lagoons to open coastal systems that receive differing amounts of freshwater runoff and also differ markedly in their exchange characteristics with shelf waters. Our temporal and spatial effort included field sampling during the ice covered period in a number of lagoons characterized by differences in their exchange characteristics with the nearshore shelf. Our preliminary chemical and biological measurements, the first of their kind in arctic coastal lagoons, reveal that lagoon benthos can become hypersaline (43) and net heterotrophic (values to 30% oxygen saturation) during winter, before rebounding during the period of ice break-up to net autotrophic (>100% saturation) under continued hypersaline conditions. Measurements of water and sediment chemistry, benthic and water column community characteristics, and natural abundance isotopic tracers promise to reveal the dynamic nature of these productive lagoon ecosystems under different hydrologic conditions. The possible role of terrestrially derived carbon to arctic estuarine food webs is especially important in view of

  7. Occurrence and Diversity of Tetracycline Resistance Genes in Lagoons and Groundwater Underlying Two Swine Production Facilities

    USGS Publications Warehouse

    Chee-Sanford, J. C.; Aminov, R.I.; Krapac, I.J.; Garrigues-Jeanjean, N.; Mackie, R.I.

    2001-01-01

    In this study, we used PCR typing methods to assess the presence of tetracycline resistance determinants conferring ribosomal protection in waste lagoons and in groundwater underlying two swine farms. All eight classes of genes encoding this mechanism of resistance [tet(O), tet(Q), tet(W), tet(M), tetB(P), tet(S), tet(T), and otrA] were found in total DNA extracted from water of two lagoons. These determinants were found to be seeping into the underlying groundwater and could be detected as far as 250 m downstream from the lagoons. The identities and origin of these genes in groundwater were confirmed by PCR-denaturing gradient gel electrophoresis and sequence analyses. Tetracycline-resistant bacterial isolates from groundwater harbored the tet(M) gene, which was not predominant in the environmental samples and was identical to tet(M) from the lagoons. The presence of this gene in some typical soil inhabitants suggests that the vector of antibiotic resistance gene dissemination is not limited to strains of gastrointestinal origin carrying the gene but can be mobilized into the indigenous soil microbiota. This study demonstrated that tet genes occur in the environment as a direct result of agriculture and suggested that groundwater may be a potential source of antibiotic resistance in the food chain.

  8. Tidal flushing and wind driven circulation of Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia) from in situ observations and numerical modelling.

    PubMed

    Dumas, F; Le Gendre, R; Thomas, Y; Andréfouët, S

    2012-01-01

    Hydrodynamic functioning and water circulation of the semi-closed deep lagoon of Ahe atoll (Tuamotu Archipelago, French Polynesia) were investigated using 1 year of field data and a 3D hydrodynamical model. Tidal amplitude averaged less than 30 cm, but tide generated very strong currents (2 ms(-1)) in the pass, creating a jet-like circulation that partitioned the lagoon into three residual circulation cells. The pass entirely flushed excess water brought by waves-induced radiation stress. Circulation patterns were computed for climatological meteorological conditions and summarized with stream function and flushing time. Lagoon hydrodynamics and general overturning circulation was driven by wind. Renewal time was 250 days, whereas the e-flushing time yielded a lagoon-wide 80-days average. Tide-driven flush through the pass and wind-driven overturning circulation designate Ahe as a wind-driven, tidally and weakly wave-flushed deep lagoon. The 3D model allows studying pearl oyster larvae dispersal in both realistic and climatological conditions for aquaculture applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Dynamics and contaminants in the coastal lagoon system of Nichupte-Bojórquez located in the Peninsula of Yucatan, Mexico

    NASA Astrophysics Data System (ADS)

    Carbajal, N.; Gaviño, J.; Galicia, M. A.

    2007-05-01

    Measurements of hydrographic parameters like temperature, salinity, pH, turbidity, dissolved oxygen and determination of concentrations of contaminants like ammonia, surfactants, phosphate, nitrite and nitrate give a picture about the degradation of the lagoon system of Nichupté-Bojórquez. Numerical experiments reveal that the tidal circulation is not intense enough to induce an efficient exchange of water. Tidal currents are small and limited to regions near the two mouths which connect the lagoon system with the Caribbean Sea. The circulation induced by wind forcing is more effective in generating strong currents in the different lagoons of the system. The wind induced circulation reduces the residence time of water. To explain the observed distribution of contaminants, we also simulate numerically the dispersion of contaminants. We present a general picture of the environmental problems of this beautiful lagoon system.

  10. Evidence for limited exchange of avian influenza viruses between seaducks and dabbling ducks at Alaska Peninsula coastal lagoons

    USGS Publications Warehouse

    Ramey, Andy M.; Pearce, John M.; Reeves, A.B.; Franson, J. Christian; Petersen, Margaret R.; Ip, Hon S.

    2011-01-01

    Avian influenza virus (AIV) prevalence and sequence data were analyzed for Steller's eiders (Polysticta stelleri) to assess the role of this species in transporting virus genes between continents and maintaining a regional viral reservoir with sympatric northern pintails (Anas acuta). AIV prevalence was 0.2% at Izembek Lagoon and 3.9% at Nelson Lagoon for Steller's eiders and 11.2% for northern pintails at Izembek Lagoon. Phylogenetic analysis of 13 AIVs from Steller's eiders revealed that 4.9% of genes were of Eurasian origin. Seven subtypes were detected, including two also observed in northern pintails. No AIV strains were highly similar (> 99%) at all gene segments between species; however, highly similar individual genes were detected. The proportion of highly similar genes was greater within rather than between species. Steller's eiders likely transport AIV genes between continents through long-distance migratory movements. Differences in AIV prevalence, subtype distribution, and the proportion of highly similar genes suggest limited AIV exchange between Steller's eiders and northern pintails at Alaska Peninsula coastal lagoons during autumn.

  11. Evidence for limited exchange of avian influenza viruses between seaducks and dabbling ducks at Alaska Peninsula coastal lagoons.

    PubMed

    Ramey, Andrew M; Pearce, John M; Reeves, Andrew B; Franson, J Christian; Petersen, Margaret R; Ip, Hon S

    2011-10-01

    Avian influenza virus (AIV) prevalence and sequence data were analyzed for Steller's eiders (Polysticta stelleri) to assess the role of this species in transporting virus genes between continents and maintaining a regional viral reservoir with sympatric northern pintails (Anas acuta). AIV prevalence was 0.2% at Izembek Lagoon and 3.9% at Nelson Lagoon for Steller's eiders and 11.2% for northern pintails at Izembek Lagoon. Phylogenetic analysis of 13 AIVs from Steller's eiders revealed that 4.9% of genes were of Eurasian origin. Seven subtypes were detected, including two also observed in northern pintails. No AIV strains were highly similar (> 99%) at all gene segments between species; however, highly similar individual genes were detected. The proportion of highly similar genes was greater within rather than between species. Steller's eiders likely transport AIV genes between continents through long-distance migratory movements. Differences in AIV prevalence, subtype distribution, and the proportion of highly similar genes suggest limited AIV exchange between Steller's eiders and northern pintails at Alaska Peninsula coastal lagoons during autumn.

  12. USSR Report, International Affairs, The Working Class and the Contemporary World, Number 2, March-April 1986.

    DTIC Science & Technology

    1986-07-31

    3. Ibid., p 36. 4. "Yearbook of Labor Statistics. 1984," Geneva, 1984, p 827; G. Farrel, "Mercado de trabajo urbano y el movimiento sindiecal...Frente de liberacion nacional y social," Buenos .Aires, 1984, p 51. 10. EL PERIODISTA DE BUENOS AIRES, Buenos Aires, 1985, No 61, p 6. 11. OPINION...documents of the 27th CPSU Congress correctly point out, has set difficult tasks "for the young and rapidly growing working class in Asia , Africa and

  13. Influence of salinity regime on the food-web structure and feeding ecology of fish species from Mediterranean coastal lagoons

    NASA Astrophysics Data System (ADS)

    Prado, Patricia; Vergara, Carolina; Caiola, Nuno; Ibáñez, Carles

    2014-02-01

    Dual δ15N and δ13C analyses and estimates of biomass were used to characterize the food webs of valuable fish species in three coastal lagoons of the Ebro Delta subjected to contrasting salinity regimes (polyhaline in the Tancada lagoon, mesohaline in the Encanyissada and oligohaline in the Clot lagoon). The δ13C signatures of the entire food-web including primary producers, sediment organic matter and consumers showed the most enriched values in the Tancada lagoon (from approx. -4.8‰ in sediments to -19.7‰ in fish) and the most depleted ones in the Clot lagoon (from approx. -11.4‰ in sediments to -25.4‰ in fish), consistent with dominant contributions from marine and continental sources, respectively. For δ15N, particularly high values were detected in the submersed vegetation (11.3 ± 0.3‰) together with more enriched sediment values at lower salinities (by approx. 2.5‰), suggesting that historical loadings of agricultural fertilizers are still retained by the systems and transmitted across trophic levels. Negative relationships between δ15N and salinity were also observed for the amphipod Gammarus aequicauda and the isopod Sphaeroma hookeri, suggesting some consumption of accumulated and resuspended detrital material. In contrast, δ15N signatures of fish showed lower values and inconsistent patterns, possibly because most species have a seasonal use of the lagoons. The biomass of fish species did not show a clear effect of the salinity regime (except for the mosquitofish Gambusia holbrookii), but results for mixing models suggest a diet shift from higher contribution of zooplankton size fractions in the Encanyissada (from 57 to 73%) to macrofauna at the other lagoons (from 40 to 67%). We suggest that alterations in salinity might modify the trophic dynamics of the systems from benthic to planktonic pathways, without large-scale differences in δ15N of fish suggestive of similar trophic levels.

  14. Correspondence between the distribution of hydrodynamic time parameters and the distribution of biological and chemical variables in a semi-enclosed coral reef lagoon

    NASA Astrophysics Data System (ADS)

    Torréton, Jean-Pascal; Rochelle-Newall, Emma; Jouon, Aymeric; Faure, Vincent; Jacquet, Séverine; Douillet, Pascal

    2007-09-01

    Hydrodynamic modeling can be used to spatially characterize water renewal rates in coastal ecosystems. Using a hydrodynamic model implemented over the semi-enclosed Southwest coral lagoon of New Caledonia, a recent study computed the flushing lag as the minimum time required for a particle coming from outside the lagoon (open ocean) to reach a specific station [Jouon, A., Douillet, P., Ouillon, S., Fraunié, P., 2006. Calculations of hydrodynamic time parameters in a semi-opened coastal zone using a 3D hydrodynamic model. Continental Shelf Research 26, 1395-1415]. Local e -flushing time was calculated as the time requested to reach a local grid mesh concentration of 1/e from the precedent step. Here we present an attempt to connect physical forcing to biogeochemical functioning of this coastal ecosystem. An array of stations, located in the lagoonal channel as well as in several bays under anthropogenic influence, was sampled during three cruises. We then tested the statistical relationships between the distribution of flushing indices and those of biological and chemical variables. Among the variables tested, silicate, chlorophyll a and bacterial biomass production present the highest correlations with flushing indices. Correlations are higher with local e-flushing times than with flushing lags or the sum of these two indices. In the bays, these variables often deviate from the relationships determined in the main lagoon channel. In the three bays receiving significant riverine inputs, silicate is well above the regression line, whereas data from the bay receiving almost insignificant freshwater inputs generally fit the lagoon channel regressions. Moreover, in the three bays receiving important urban and industrial effluents, chlorophyll a and bacterial production of biomass generally display values exceeding the lagoon channel regression trends whereas in the bay under moderate anthropogenic influence values follow the regressions obtained in the lagoon channel

  15. Zooplankton responses to sandbar opening in a tropical eutrophic coastal lagoon

    NASA Astrophysics Data System (ADS)

    Santangelo, Jayme M.; de M. Rocha, Adriana; Bozelli, Reinaldo L.; Carneiro, Luciana S.; de A. Esteves, Francisco

    2007-02-01

    The effects of a disturbance by sandbar opening on the zooplankton community were evaluated through a long-term study in an eutrophic and oligohaline system, Imboassica Lagoon, Rio de Janeiro, Brazil. Zooplankton samples and limnological data were collected monthly from March 2000 to February 2003. Before the sandbar was opened in February 2001, the lagoon showed eutrophic conditions, with high mean nutrient concentrations and low salinity (total nitrogen - TN = 190.28 μM, chlorophyll a content - Chl. a = 104.60 μg/L and salinity = 0.87'). During this period, the zooplankton species present, such as the rotifers Brachionus calyciflorus and Brachionus havanaensis, were typical of freshwater to oligohaline and eutrophic environments. After the sandbar opening, the lagoon changed to a lower trophic status and increased salinity (TN = 55.11 μM, Chl. a = 27.56 μg/L and salinity = 19.64'). As a result, the zooplankton community came to consist largely of the rotifer Brachionus plicatilis, marine copepods and meroplanktonic larvae, mainly Gastropoda. Salinity was the main force structuring the zooplankton community after the sandbar opening. Two years after this episode, the prior zooplankton community had not reestablished itself, indicating a low resilience to this disturbance. The conditions developed prior to a sandbar opening can be crucial to the community responses in the face of this disturbance and for the capacity of the original zooplankton community to re-establish itself.

  16. Biological control of trace metal and organometal benthic fluxes in a eutrophic lagoon (Thau Lagoon, Mediterranean Sea, France)

    NASA Astrophysics Data System (ADS)

    Point, D.; Monperrus, M.; Tessier, E.; Amouroux, D.; Chauvaud, L.; Thouzeau, G.; Jean, F.; Amice, E.; Grall, J.; Leynaert, A.; Clavier, J.; Donard, O. F. X.

    2007-04-01

    In situ benthic chamber experiments were conducted in the Thau Lagoon that allowed the simultaneous determination of the benthic exchanges of trace metals (Cd, Co, Cu, Mn, Pb and U) and mercury species (iHg and MMHg). Fluxes of organotin compounds (MBT, DBT and TBT) were also investigated for the first time. The benthic incubations were performed during two campaigns at four stations that presented different macrobenthic and macrophytic species distribution and abundance (see [Thouzeau, G., Grall, J., Clavier, J., Chauvaud, L., Jean, F., Leynaert, A., Longpuirt, S., Amice, E., Amouroux, D., 2007. Spatial and temporal variability of benthic biogeochemical fluxes associated with macrophytic and macrofaunal distributions in the Thau lagoon (France). Estuarine, Coastal and Shelf Science 72 (3), 432 446.]). The results indicate that most of the flux intensity as well as the temporal and spatial variability can be explained by the combined influence of microscale and macroscale processes. Microscale changes were identified using Mn flux as a good indicator of the redox conditions at the sediment water interface, and by extension, as an accurate proxy of benthic fluxes for most trace metals and mercury species. We also observed that the redox gradient at the interface is promoted by both microbial and macrobenthic species activity that governs O2 budgets. Macroscale processes have been investigated considering macrobenthic organisms activity (macrofauna and macroalgal cover). The density of such macroorganisms is able to explain most of the spatial and temporal variability of the benthic metal fluxes within a specific site. A tentative estimation of the flux of metals and organometals associated with deposit feeder and suspension feeder activity was found to be in the range of the flux determined within the chambers for most considered elements. Furthermore, a light/dark incubation investigating a dense macroalgal cover present at the sediment surface illustrates the role

  17. Anatomy of the Holocene succession of the southern Venice lagoon revealed by very high-resolution seismic data

    NASA Astrophysics Data System (ADS)

    Zecchin, Massimo; Brancolini, Giuliano; Tosi, Luigi; Rizzetto, Federica; Caffau, Mauro; Baradello, Luca

    2009-05-01

    The southern portion of the Venice lagoon contains a relatively thick (up to 20 m) Holocene sedimentary body that represents a detailed record of the formation and evolution of the lagoon. New very high-resolution (VHR) seismic profiles provided a detailed investigation on depositional geometries, internal bounding surfaces and stratal relationships. These informations, combined with core analysis, allowed the identification of large- to medium-scale sedimentary structures (e.g. dunes, point bars), the corresponding sedimentary environment, and of retrogradational and progradational trends. In addition, the availability of dense seismic network produced a 3D reconstruction of the southern lagoon and the recognition of the along-strike and dip variability of the stratal architecture. Three main seismic units (H1-H3), separated by key stratal surfaces (S1-S3), form the Holocene succession in the southern Venice lagoon. This succession is bounded at the base by the Pleistocene/Holocene boundary (the surface S1), which consists of a surface of subaerial exposure locally subjected to river incision. The lower part of the Holocene succession (up to 13 m thick) consists of incised valley fills passing upward into lagoon and then shallow-marine sediments (Unit H1), and therefore shows a deepening-upward trend and a retrogradational stacking pattern. A prograding delta and adjacent shorelines, showing internal clinoforms downlapping onto the top of Unit H1 (the surface S2), form the middle part of the Holocene succession (Unit H2, up to 7.5 m thick). Unit H2 is interpreted as a result of a regressive phase started about 6 kyr BP and continued until recent time. The upper part of the Holocene succession (Unit H3) consists of lagoonal deposits, including tidal channel and tidal and subtidal flat sediments, that abruptly overlie Unit H2. Unit H3 is thought to represent a drowning of the area primarily due to human interventions that created rivers diversion and consequent

  18. Biodiversity of Saline and Brakish Marshes of the Indian River Lagoon: Historic and Current Patterns

    NASA Technical Reports Server (NTRS)

    Schmalzer, Paul A.

    1995-01-01

    The Indian River Lagoon (IRL) crosses a zone of climatic transition. Historically, marshes dominated saline and brackish environments in the north of the lagoon, while mangroves became important to the south. Distribution of marsh communities was influenced by hydrology, salinity, soil characteristics, and fire, as well as periodic freezes. Marshes of the IRL have been greatly modified since the 1940s. Despite significant modifications, marsh plant species have not been lost from the region, but community and landscape patterns have been greatly modified and ecosystem processes altered.

  19. Sources of fecal indicator bacteria to groundwater, Malibu Lagoon and the near-shore ocean, Malibu, California, USA

    USGS Publications Warehouse

    Izbicki, John A.; Swarzenski, Peter W.; Burton, Carmen A.; Van De Werfhorst, Laurie; Holden, Patricia A.; Dubinsky, Eric A.

    2012-01-01

    Onsite wastewater treatment systems (OWTS) used to treat residential and commercial sewage near Malibu, California have been implicated as a possible source of fecal indicator bacteria (FIB) to Malibu Lagoon and the near-shore ocean. For this to occur, treated wastewater must first move through groundwater before discharging to the Lagoon or ocean. In July 2009 and April 2010, δ18O and δD data showed that some samples from water-table wells contained as much as 70% wastewater; at that time FIB concentrations in those samples were generally less than the detection limit of 1 Most Probable Number (MPN) per 100 milliliters (mL). In contrast, Malibu Lagoon had total coliform, Escherichia coli, and enterococci concentrations as high as 650,000, 130,000, and 5,500 MPN per 100 mL, respectively, and as many as 12% of samples from nearby ocean beaches exceeded the U.S. Environmental Protection Agency single sample enterococci standard for marine recreational water of 104 MPN per 100 mL. Human-associated Bacteroidales, an indicator of human-fecal contamination, were not detected in water from wells, Malibu Lagoon, or the near-shore ocean. Similarly, microarray (PhyloChip) data show Bacteroidales and Fimicutes Operational Taxanomic Units (OTUs) present in OWTS were largely absent in groundwater; in contrast, 50% of Bacteroidales and Fimicutes OTUs present in the near-shore ocean were also present in gull feces. Terminal-Restriction Length Fragment Polymorphism (T-RFLP) and phospholipid fatty acid (PLFA) data showed that microbial communities in groundwater were different and less abundant than communities in OWTS, Malibu Lagoon, or the near-shore ocean. However, organic compounds indicative of wastewater (such as fecal sterols, bisphenol-A and cosmetics) were present in groundwater having a high percentage of wastewater and were present in groundwater discharging to the ocean. FIB in the near-shore ocean varied with tides, ocean swells, and waves. Movement of water from

  20. Molecular Characterization of Swine Manure Lagoon Microbial and Antibiotic Resistant Populations

    USDA-ARS?s Scientific Manuscript database

    Background: The differences in swine manure lagoon effluent based on differing management styles or approaches such as different stages of swine rearing determines the presence of variable antibiotic resistance determinants and functional microbial populations. These concerns determine the suitabil...

  1. Biogeochemical cycling and phyto- and bacterioplankton communities in a large and shallow tropical lagoon (Términos Lagoon, Mexico) under 2009-2010 El Niño Modoki drought conditions

    NASA Astrophysics Data System (ADS)

    Conan, Pascal; Pujo-Pay, Mireille; Agab, Marina; Calva-Benítez, Laura; Chifflet, Sandrine; Douillet, Pascal; Dussud, Claire; Fichez, Renaud; Grenz, Christian; Gutierrez Mendieta, Francisco; Origel-Moreno, Montserrat; Rodríguez-Blanco, Arturo; Sauret, Caroline; Severin, Tatiana; Tedetti, Marc; Torres Alvarado, Rocío; Ghiglione, Jean-François

    2017-03-01

    The 2009-2010 period was marked by an episode of intense drought known as the El Niño Modoki event. Sampling of the Términos Lagoon (Mexico) was carried out in November 2009 in order to understand the influence of these particular environmental conditions on organic matter fluxes within the lagoon's pelagic ecosystem and, more specifically, on the relationship between phyto- and bacterioplankton communities. The measurements presented here concern biogeochemical parameters (nutrients, dissolved and particulate organic matter [POM], and dissolved polycyclic aromatic hydrocarbons [PAHs]), phytoplankton (biomass and photosynthesis), and bacteria (diversity and abundance, including PAH degradation bacteria and ectoenzymatic activities). During the studied period, the water column of the Términos Lagoon functioned globally as a sink and, more precisely, as a nitrogen assimilator. This was due to the high production of particulate and dissolved organic matter (DOM), even though exportation of autochthonous matter to the Gulf of Mexico was weak. We found that bottom-up control accounted for a large portion of the variability of phytoplankton productivity. Nitrogen and phosphorus stoichiometry mostly accounted for the heterogeneity in phytoplankton and free-living prokaryote distribution in the lagoon. In the eastern part, we found a clear decoupling between areas enriched in dissolved inorganic nitrogen near the Puerto Real coastal inlet and areas enriched in phosphate (PO4) near the Candelaria estuary. Such a decoupling limited the potential for primary production, resulting in an accumulation of dissolved organic carbon and nitrogen (DOC and DON, respectively) near the river mouths. In the western part of the lagoon, maximal phytoplankton development resulted from bacterial activity transforming particulate organic phosphorus (PP) and dissolved organic phosphorus (DOP) to available PO4 and the coupling between Palizada River inputs of nitrate (NO3) and

  2. HIV and Other Sexually Transmitted Infections among Men Who Have Sex with Men Recruited by RDS in Buenos Aires, Argentina: High HIV and HPV Infection

    PubMed Central

    Pando, María A.; Balán, Iván C.; Marone, Rubén; Dolezal, Curtis; Leu, Cheng-Shiun; Squiquera, Luis; Barreda, Victoria; Rodriguez Fermepín, Marcelo; Gallo Vaulet, Lucia; Rey, Jorge; Picconi, María; Carballo-Diéguez, Alex; Avila, María M.

    2012-01-01

    Background The aim of this study was to estimate the prevalence of HIV and other STIs, among MSM from Buenos Aires (2007–2009). Methods Responding Driven Sampling was used for recruitment of MSM. Participants completed a structured web-based survey and provided biological samples. Results A total of 496 MSM were studied for HIV, HBV, HCV, and T pallidum infections. Chlamydia and HPV diagnoses were only performed in 98 and 109 participants, respectively. Prevalence of HIV was 17.3%, HBV 22.9%, HCV 7.5%, T pallidum 20.5%, HPV 83.5%, and C trachomatis 1.7%. In the year prior to the evaluation, 71% of the participants had had sex with men and/or trans and women (MMW) while 29% had not had sex with women (MM). Comparing MM to MMW, prevalence of HIV (30.7% vs. 11.9%, p<0.001), HBV (36.4% vs. 17.8%, p<0.001), T pallidum (32.1% vs. 15.7%, p<0.001), and HPV (88.3% vs. 70.4%, p = 0.039) were significantly higher among MM, whereas no significant differences were found for HCV and C trachomatis. The MM group had also significantly higher HIV incidence (5.60 vs. 4.28 per 100 persons-year, p = 0.032). HPV genotypes 16, 6, and 11 were the most frequently found; 40.7% of the MSM had more than one genotype and one high risk genotype was detected in 43.6% of participants. Conclusions Both MM and MMW are at high risk of infection for HIV and other STIs. Rates of HIV, HBV, T pallidum and HPV infections are higher in the MM group. PMID:22768137

  3. VISTA Stares Deeply into the Blue Lagoon

    NASA Astrophysics Data System (ADS)

    2011-01-01

    This new infrared image of the Lagoon Nebula was captured as part of a five-year study of the Milky Way using ESO's VISTA telescope at the Paranal Observatory in Chile. This is a small piece of a much larger image of the region surrounding the nebula, which is, in turn, only one part of a huge survey. Astronomers are currently using ESO's Visible and Infrared Survey Telescope for Astronomy (VISTA) to scour the Milky Way's central regions for variable objects and map its structure in greater detail than ever before. This huge survey is called VISTA Variables in the Via Lactea (VVV) [1]. The new infrared image presented here was taken as part of this survey. It shows the stellar nursery called the Lagoon Nebula (also known as Messier 8, see eso0936), which lies about 4000-5000 light-years away in the constellation of Sagittarius (the Archer). Infrared observations allow astronomers to peer behind the veil of dust that prevents them from seeing celestial objects in visible light. This is because visible light, which has a wavelength that is about the same size as the dust particles, is strongly scattered, but the longer wavelength infrared light can pass through the dust largely unscathed. VISTA, with its 4.1-metre diameter mirror - the largest survey telescope in the world - is dedicated to surveying large areas of the sky at near-infrared wavelengths deeply and quickly. It is therefore ideally suited to studying star birth. Stars typically form in large molecular clouds of gas and dust, which collapse under their own weight. The Lagoon Nebula, however, is also home to a number of much more compact regions of collapsing gas and dust, called Bok globules [2]. These dark clouds are so dense that, even in the infrared, they can block the starlight from background stars. But the most famous dark feature in the nebula, for which it is named, is the lagoon-shaped dust lane that winds its way through the glowing cloud of gas. Hot, young stars, which give off intense

  4. NPDES Permit for Lower Brule Wastewater Lagoon System in South Dakota

    EPA Pesticide Factsheets

    Under NPDES permit number SD-0020800, Lower Brule Rural Water is authorized to discharge from its wastewater lagoon system serving the town of Lower Brule, located in Lyman County, South Dakota, to the bank of the Missouri River (Lake Sharpe).

  5. Can Biochar Covers Reduce Emissions from Manure Lagoons While Capturing Nutrients?

    EPA Science Inventory

    The unique physical and chemical properties of biochars make them promising materials for odor, gas, and nutrient sorption. Floating covers made from organic materials (biocovers) are one option for reducing odor and gas emissions from livestock manure lagoons. This study evaluat...

  6. Diazotrophic bacterioplankton in a coral reef lagoon: phylogeny, diel nitrogenase expression and response to phosphate enrichment.

    PubMed

    Hewson, Ian; Moisander, Pia H; Morrison, Amanda E; Zehr, Jonathan P

    2007-05-01

    We investigated diazotrophic bacterioplankton assemblage composition in the Heron Reef lagoon (Great Barrier Reef, Australia) using culture-independent techniques targeting the nifH fragment of the nitrogenase gene. Seawater was collected at 3 h intervals over a period of 72 h (i.e. over diel as well as tidal cycles). An incubation experiment was also conducted to assess the impact of phosphate (PO(4)3*) availability on nifH expression patterns. DNA-based nifH libraries contained primarily sequences that were most similar to nifH from sediment, microbial mat and surface-associated microorganisms, with a few sequences that clustered with typical open ocean phylotypes. In contrast to genomic DNA sequences, libraries prepared from gene transcripts (mRNA amplified by reverse transcription-polymerase chain reaction) were entirely cyanobacterial and contained phylotypes similar to those observed in open ocean plankton. The abundance of Trichodesmium and two uncultured cyanobacterial phylotypes from previous studies (group A and group B) were studied by quantitative-polymerase chain reaction in the lagoon samples. These were detected as transcripts, but were not detected in genomic DNA. The gene transcript abundance of these phylotypes demonstrated variability over several diel cycles. The PO(4)3* enrichment experiment had a clearer pattern of gene expression over diel cycles than the lagoon sampling, however PO(4)3* additions did not result in enhanced transcript abundance relative to control incubations. The results suggest that a number of diazotrophs in bacterioplankton of the reef lagoon may originate from sediment, coral or beachrock surfaces, sloughing into plankton with the flooding tide. The presence of typical open ocean phylotype transcripts in lagoon bacterioplankton may indicate that they are an important component of the N cycle of the coral reef.

  7. Very high incidence of syphilis in HIV-infected men who have sex with men in Buenos Aires city: a retrospective cohort study.

    PubMed

    Bissio, E; Cisneros, V; Lopardo, G D; Cassetti, L I

    2017-08-01

    The incidence of sexually transmitted infections (STIs), particularly syphilis, is high and continues to rise among some populations, especially among men who have sex with men (MSM). Furthermore, a higher incidence of STIs has been reported in HIV-positive than in HIV-negative MSM. To determine the incidence of syphilis in a cohort of men with HIV in Buenos Aires city. Retrospective cohort study. We examined the records and visits made by men with HIV aged >18 years in our institution during a 1-year period. Venereal Disease Reference Laboratory (VDRL) results for all the men in our cohort during the study period were analysed. We considered a case of syphilis as incident if a person had a VDRL result of ≥16 DILS, provided that this was increased at least fourfold compared with a previous determination. All VDRL results ≤8 were investigated, and analysed together with the medical records, to determine if they were new cases. We analysed the VDRL results and the clinical records of 1150 men followed up in our centre during the study period. Mean age was 40.9 years. According to the definition used, we registered 171 new cases of syphilis-that is, an incidence of 14.9/100 patients/year (95% CI 12.9 to 17.0). No significant differences in incidence according to age group were found, but there was a trend towards a lower incidence in older men. Ten men had two new episodes during the study. The incidence of syphilis in this cohort of men with HIV (predominantly MSM) was very high. In addition to maintaining high surveillance for early diagnosis and treatment, it is necessary to implement newer and more effective measures to prevent syphilis and other STIs in this population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. Coastal Evolution in a Mediterranean Microtidal Zone: Mid to Late Holocene Natural Dynamics and Human Management of the Castelló Lagoon, NE Spain.

    PubMed

    Ejarque, Ana; Julià, Ramon; Reed, Jane M; Mesquita-Joanes, Francesc; Marco-Barba, Javier; Riera, Santiago

    2016-01-01

    We present a palaeoenvironmental study of the Castelló lagoon (NE Spain), an important archive for understanding long-term interactions between dynamic littoral ecosystems and human management. Combining geochemistry, mineralogy, ostracods, diatoms, pollen, non-pollen palynomorphs, charcoal and archaeo-historical datasets we reconstruct: 1) the transition of the lagoon from a marine to a marginal environment between ~3150 cal BC to the 17th century AD; 2) fluctuations in salinity; and 3) natural and anthropogenic forces contributing to these changes. From the Late Neolithic to the Medieval period the lagoon ecosystem was driven by changing marine influence and the land was mainly exploited for grazing, with little evidence for impact on the natural woodland. Land-use exploitation adapted to natural coastal dynamics, with maximum marine flooding hampering agropastoral activities between ~1550 and ~150 cal BC. In contrast, societies actively controlled the lagoon dynamics and become a major agent of landscape transformation after the Medieval period. The removal of littoral woodlands after the 8th century was followed by the expansion of agrarian and industrial activities. Regional mining and smelting activities polluted the lagoon with heavy metals from the ~11th century onwards. The expansion of the milling industry and of agricultural lands led to the channelization of the river Muga into the lagoon after ~1250 cal AD. This caused its transformation into a freshwater lake, increased nutrient load, and the infilling and drainage of a great part of the lagoon. By tracking the shift towards an anthropogenically-controlled system around ~750 yr ago, this study points out Mediterranean lagoons as ancient and heavily-modified systems, with anthropogenic impacts and controls covering multi-centennial and even millennial timescales. Finally, we contributed to the future construction of reliable seashell-based chronologies in NE Spain by calibrating the Banyuls-sur-Mer

  9. Coastal Evolution in a Mediterranean Microtidal Zone: Mid to Late Holocene Natural Dynamics and Human Management of the Castelló Lagoon, NE Spain

    PubMed Central

    Ejarque, Ana; Julià, Ramon; Reed, Jane M.; Mesquita-Joanes, Francesc; Marco-Barba, Javier; Riera, Santiago

    2016-01-01

    We present a palaeoenvironmental study of the Castelló lagoon (NE Spain), an important archive for understanding long-term interactions between dynamic littoral ecosystems and human management. Combining geochemistry, mineralogy, ostracods, diatoms, pollen, non-pollen palynomorphs, charcoal and archaeo-historical datasets we reconstruct: 1) the transition of the lagoon from a marine to a marginal environment between ~3150 cal BC to the 17th century AD; 2) fluctuations in salinity; and 3) natural and anthropogenic forces contributing to these changes. From the Late Neolithic to the Medieval period the lagoon ecosystem was driven by changing marine influence and the land was mainly exploited for grazing, with little evidence for impact on the natural woodland. Land-use exploitation adapted to natural coastal dynamics, with maximum marine flooding hampering agropastoral activities between ~1550 and ~150 cal BC. In contrast, societies actively controlled the lagoon dynamics and become a major agent of landscape transformation after the Medieval period. The removal of littoral woodlands after the 8th century was followed by the expansion of agrarian and industrial activities. Regional mining and smelting activities polluted the lagoon with heavy metals from the ~11th century onwards. The expansion of the milling industry and of agricultural lands led to the channelization of the river Muga into the lagoon after ~1250 cal AD. This caused its transformation into a freshwater lake, increased nutrient load, and the infilling and drainage of a great part of the lagoon. By tracking the shift towards an anthropogenically-controlled system around ~750 yr ago, this study points out Mediterranean lagoons as ancient and heavily-modified systems, with anthropogenic impacts and controls covering multi-centennial and even millennial timescales. Finally, we contributed to the future construction of reliable seashell-based chronologies in NE Spain by calibrating the Banyuls-sur-Mer

  10. An Analysis of Shoreline Change At Little Lagoon, Alabama

    DTIC Science & Technology

    2006-06-14

    AN ANALYSIS OF SHORELINE CHANGE AT LITTLE LAGOON, ALABAMA By Glen R. Gibson THESIS...control number. 1. REPORT DATE 14 JUN 2006 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE An Analysis Of Shoreline Change At...correlation analysis conducted on the gulf shoreline and Little Lagoon’s southern shoreline showed that although weak overall correlation values

  11. The Influence of Wind and Tide on the Hydrodynamics of a Highly Frictional Coastal Lagoon System

    NASA Astrophysics Data System (ADS)

    Polanco-Arias, C.; Marino-Tapia, I.; Enriquez, C.

    2016-02-01

    This study is focused on the influence of wind and tide on the hydrodynamics of a tropical coastal lagoon in Telchac, Yucatan, Mexico. The system is very shallow (z < 1m) and covered with a rim of mangrove forests, both aspects that enhance its frictional characteristics. The lagoon is an important habitat for the exotic flamingo birds and several species of fish, but also is used for fishing and serves as a harbor for small boats. Water level and velocity data gathered during one month in the summer of 2009, shows the expected attenuation of the tidal signal in the head of the system, but during the final ten days of the campaign there is an unusual behavior where the water level in the lagoon head was between 16% and 33% bigger than in the lagoon mouth. Analysis of the data shows a high coherence between the sea level and the wind velocity, primarily at diurnal frequencies. This reinforces the hypothesis of a synchronization between strong sea breezes and the predominant diurnal tide in such a way that amplification of the diurnal signal can occur at the head. Numerical simulations using the Delft3D model are performed to confirm this hypothesis and to better understand the conditions under which such phenomenon can occur. The effects of basin orientation, shape and depth are investigated with the numerical model.

  12. Nutrient dynamics in tropical rivers, estuarine-lagoons, and coastal ecosystems along the eastern Hainan Island

    NASA Astrophysics Data System (ADS)

    Li, R. H.; Liu, S. M.; Li, Y. W.; Zhang, G. L.; Ren, J. L.; Zhang, J.

    2013-06-01

    Nutrient dynamics were studied along the eastern Hainan Island based on field observations during 2006-2009, to understand nutrient biogeochemical processes and to have an overview of human perturbations on coastal ecosystems in this tropical region. The concentrations of nutrients in the rivers had seasonal variations enriched with dissolved inorganic nitrogen (DIN). High riverine concentrations of nitrate were mainly originated from agricultural fertilizer input. The ratios of DIN : PO43- ranged from 37 to 1063, suggesting preferential PO43- relative to nitrogen in the rivers. The areal yields of dissolved silicate (DSi) varied from 76 to 448 × 103 mol km-2 yr-1 due to erosion over the drainage area, inducing high levels of DSi among worldwide tropical systems. Aquaculture ponds contained high concentrations of NH4+ (up to 157 μM) and DON (up to 130 μM). Particulate phosphorus concentrations (0.5 ∼1.4 μM) were in lower level comparied with estuaries around the world. Particulate silicate levels in rivers and lagoons were lower than global average level. Nutrient biogeochemistry in coastal areas were affected by human activities (e.g. aquaculture, agriculture), as well as natural events such as typhoon. Nutrient concentrations were low because open sea water dispersed land-derived nutrients. Nutrient budgets were built based on a steady-state box model, which showed that riverine fluxes would be magnified by estuarine processes (e.g. regeneration, desorption) in the Wenchanghe/Wenjiaohe Estuary, Wanquan River estuary, and the Laoyehai Lagoon except in the Xiaohai Lagoon. Riverine and groundwater input were the major sources of nutrients to the Xiaohai Lagoon and the Laiyehai Lagoon, respectively. Riverine input and aquaculture effluent were the major sources of nutrients to the eastern coastal of Hainan Island. Nutrient inputs to the coastal ecosystem can be increased by typhoon-induced runoff of rainwater, and phytoplankton bloom in the sea would be

  13. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires

    PubMed Central

    Balán, Iván C.; Carballo-Diéguez, Alex; Marone, Rubén O.; Pando, María A.; Barreda, Victoria; Ávila, María M.

    2011-01-01

    Resumen El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  14. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires.

    PubMed

    Balán, Iván C; Carballo-Diéguez, Alex; Marone, Rubén O; Pando, María A; Barreda, Victoria; Avila, María M

    2011-03-01

    El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin.

  15. Temporal and spatial fluctuations of phytoplankton in a tropical coastal lagoon, southeast Brazil.

    PubMed

    Melo, S; Bozelli, R L; Esteves, F A

    2007-08-01

    Spatial and temporal variability of the phytoplankton community in the tropical coastal Imboassica lagoon, an environment naturally isolated from the ocean by a narrow sandbar, was analysed every two weeks for 19 months by sampling three sites. During this study, the lagoon received direct input of marine water three times, resulting in remarkable salinity, nutrient concentrations and phytoplankton biomass variations in both temporal and spatial aspects. The phytoplankton biomass presented relatively low values ranging, on average, from 0.54 mg x L(-1) in the station closest to the sea (station 1) to 1.34 mg x L(-1) in the station close to a macrophyte bank (station 3). Diatoms and cryptomonads dominated in stations 1 and 2 (located relatively close to station 1, yet receiving the runoff of domestic sewage), and euglenoids, cryptomonads and dinoflagellates at station 3. Stations 1 and 2 usually presented the same dominant species but station 2 presented a higher phytoplankton biomass. On the other hand, station 3 showed more similar results concerning phytoplankton biomass with station 2, however the dominant species were usually different. The high fluctuations of salinity and the reduced nutrient availability are pointed out as the main factors structuring the dynamics of the phytoplankton community at the Imboassica lagoon.

  16. Effects of land use changes on eutrophication indicators in five coastal lagoons of the Southwestern Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Rodríguez-Gallego, Lorena; Achkar, Marcel; Defeo, Omar; Vidal, Leticia; Meerhoff, Erika; Conde, Daniel

    2017-03-01

    Five catchment areas in Uruguay were selected to conduct a nutrient exportation analysis and to evaluate the effects of current land use on the eutrophication of coastal lagoons. Satellite images and national agriculture censuses were used for a quantitative analysis of land use changes from 1974 to 2005, and a nutrient export coefficient approximation was used to determine long-term changes in annual loads. Several eutrophication indicators (water, sediment and autotrophic communities) were assessed seasonally in the lagoon basins during 2005 and 2006. The areal annual load of nutrients exported to the lagoons increased over time. Population and extensive livestock ranching were the most important nutrient sources, while agriculture is increasing in importance. Buffer effects of riparian forests on eutrophication indicators were observed in contrast to the wetlands surrounding the lagoons, which seem to be acting as a source of nutrients. Catchment size was inversely related to most eutrophication indicators. Afforestation and agriculture were found not to directly impact eutrophication indicators, however, catchments with larger agricultural areas showed higher concentrations of suspended solids, which may indicate the export of particulate nutrients. Salinity was inversely related to most eutrophication indicators, suggesting that the manipulation of the sand bar of the lagoons is a critical management issue. Sediment-related eutrophication indicators were more sensitive to changes in land uses and covers, in contrast with the more variable water column indicators, suggesting their potential use as enduring indicators. This research provides a rapid and integral assessment for qualitatively linking catchment changes with eutrophication indicators in coastal environments, which can easily be replicated to track pollutants in locations that lack standardized monitoring programs needed for more complex catchment modeling approaches.

  17. Hepatic pathologies in the brackish water catfish (Chrysichthys nigrodigitatus) from contaminated locations of the Lagos lagoon complex

    USGS Publications Warehouse

    Olarinmoye, O.; Taiwo, V.; Clarke, E.; Kumolu-Johnson, C.; Aderinola, O.; Adekunbi, F.

    2010-01-01

    Several toxicological studies into the effects of aquatic pollutants on the liver of teleost fish exist in literature. The focus on the liver in these studies is predicated on its central nature in the scheme of biotransformation and excretion of xenobiotics following exposure in polluted water bodies. As a consequence of the latter primary role of the liver in these processes it is regarded as a predilective site for the sub lethal effects of xenobiotics on the organism usually detectable at histological level. Hepatic histopathology recorded in livers from feral populations of the brackish water catfish Chrysichthys nigrodigitatus from locations on the Lagos lagoon complex with significant anthropogenic inputs from denizen populations and industries are presented. Liver sections from sixty specimens from two locations on the Lagos lagoon complex (Badagry lagoon: 6??24'N, 2??56'E; and Lagos lagoon: 6??29'N, 3??22'E) were analysed. Observed pathologies included hydropic degeneration (58%), portal / sinusoidal congestion (33%), hepatic necrosis (26%), hemosiderosis (12%) and foci of cellular alterations (FCA's). No obvious oncologic features were observed; the presence of the hydropic Vacuolation lesion was taken as prelude to the development of neoplasms and discussed as such. ?? 2009, Penkala Bt., Budapest, Hungary.

  18. Disturbance caused by freshwater releases of different magnitude on the aquatic macroinvertebrate communities of two coastal lagoons

    NASA Astrophysics Data System (ADS)

    Cañedo-Argüelles, Miguel; Rieradevall, Maria

    2010-06-01

    The response of the aquatic macroinvertebrate communities to freshwater releases of different magnitude and persistence was investigated in two Mediterranean coastal lagoons (Ca l'Arana and Ricarda). The study was carried out during 14 months (June 2004-July 2005) in which different environmental variables and the macroinvertebrate communities associated with two different habitats, the Phragmites australis belt and the deep area of the lagoons, were sampled monthly. Additionally, potential colonizing sources were identified through the analysis of Chironomidae pupal exuviae. The initial response of the communities to the freshwater releases was similar, being characterized by a peak of opportunistic taxa (mainly Naididae), but the late response was different for each lagoon. In the Ca l'Arana, the magnitude of the freshwater release was higher (salinity dropped below five, which is the limit commonly established for most freshwater species) and its persistence was also higher, allowing the colonization of the lagoon by new insect taxa, which replaced the brackish water species. In the Ricarda, the salinity never dropped beyond five and pre-disturbance conditions were rapidly re-established. This, together with the acclimatizing mechanisms showed by the species Chironomus riparius and Hediste diversicolor, permitted the recovery of the pre-disturbance macroinvertebrate community.

  19. Millennial-scale record of overwash deposits preserved within lagoon sediments from the Arabian Peninsula

    NASA Astrophysics Data System (ADS)

    Griffis, A. M.; Jessica, P.; Reinhardt, E. G.; Kosciuch, T. J.; Kovacs, S. E.; Hoffmann, G.

    2017-12-01

    Coastlines along the Arabian Sea are susceptible to tsunami-related inundation due to their proximity to the Makran Subduction Zone (MSZ). This subduction zone has seen decades of low intensity events, but has historically produced large tsunamigenic-earthquakes that have impacted the 100 million people living along the Arabian Sea. One major problem in assessing the seismic risk of the MSZ is that the historical record of events are spatially and temporally limited and rely heavily on eye witness accounts. This hinders our ability to forecast the potential magnitude and recurrence intervals of earthquakes and tsunamis that can be expected in the future. Sediments deposited by paleotsunamis are useful as they expand the decadal record of events to include millennial timescales that more accurately capture the full range of magnitudes and recurrence intervals. On November 28, 1945 a 8.1 Mw earthquake originating from the MSZ generated a tsunami inundating coastlines along the Arabian Sea with wave heights up to 13m. At Sur, a small village on the northeastern coastline of Oman, the tsunami deposited a laterally continuous shell-rich layer within a 12 km2 lagoon. This layer contained distinctive taphonomic assemblages of foraminifera and bivalves. Below the 1945 shelly deposit at Sur Lagoon, seven anomalous sand layers were found preserved within fine-grained lagoonal sediment. These layers of medium-coarse sands range in thickness from 5 to 35 cm and are separated by sandy-mud sediment. Grain size analysis shows that these anomalously coarse layers are followed by an abrupt return to lagoonal mud. The sand layers have features consistent with the 1945 tsunami deposit such as fining upward trends, sharp basal contact, and marine foraminifera (e.g., Amphistegina sp., planktics). In contrast, the surrounding lagoon deposits are generally massive, finer in grain size, and contain foraminiferal species typically found in shallow quiescent coastal environments (e

  20. Field Sampling Plan for Closure of the Central Facilities Area Sewage Treatment Plant Lagoon 3 and Land Application Area

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewis, Michael George

    This field sampling plan describes sampling of the soil/liner of Lagoon 3 at the Central Facilities Area Sewage Treatment Plant. The lagoon is to be closed, and samples obtained from the soil/liner will provide information to determine if Lagoon 3 and the land application area can be closed in a manner that renders it safe to human health and the environment. Samples collected under this field sampling plan will be compared to Idaho National Laboratory background soil concentrations. If the concentrations of constituents of concern exceed the background level, they will be compared to Comprehensive Environmental Response, Compensation, and Liabilitymore » Act preliminary remediation goals and Resource Conservation and Recovery Act levels. If the concentrations of constituents of concern are lower than the background levels, Resource Conservation and Recovery Act levels, or the preliminary remediation goals, then Lagoon 3 and the land application area will be closed. If the Resource Conservation and Recovery Act levels and/or the Comprehensive Environmental Response, Compensation, and Liability Act preliminary remediation goals are exceeded, additional sampling and action may be required.« less