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Avaliação de bactérias fototróficas em lagoas de estabilização: diversidade, purificação e identificação; Evaluation of phototropic bacteria in stabilization lagoons: diversity, purification and identification

Saavedra del Aguila, Nora Katia
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/06/2007 PT
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As bactérias fototróficas freqüentemente apresentam florescimentos em lagoas de estabilização utilizadas no tratamento de esgoto sanitário, formando uma camada de cor púrpura na sua superfície. Portanto, o estudo das condições que propiciam tais florescimentos, a diversidade microbiana, o potencial de remoção da matéria orgânica e o estabelecimento das relações entre tais conhecimentos, permitem compreender o metabolismo do sistema. Nesse sentido, o objetivo deste trabalho foi avaliar a diversidade de bactérias (domínio Bacteria), bactérias fototróficas púrpuras e bactérias redutoras de sulfato (BRS) em lagoas de estabilização do Vale do Ribeira (Cajati, SP). Para tal, foram realizadas coletas sazonais (primavera, verão, outono e inverno) na sub-superfície, camada intermediária e interface água-sedimento, em dois horários (14:00 h e 02:00 h), nas lagoas anaeróbia e facultativa. Para analisar os diferentes grupos de microrganismos, utilizou-se a técnica de PCR/DGGE, com primers específicos. Nas análises de filogenia realizou-se o seqüenciamento parcial do gene RNAr 16S e da subunidade M do centro de reação fotossintético das bactérias fototróficas púrpuras. Análises físico-químicas, tais como sulfato...

Changes in abiotic characteristics of water in the Paranapanema River and three lateral lagoons at mouth zone of the Jurumirim Reservoir during the flood period, São Paulo, Brazil

Granado, Danielli Cristina; Henry, Raoul
Fonte: Universidade Católica de Valparaíso Publicador: Universidade Católica de Valparaíso
Tipo: Artigo de Revista Científica Formato: 79-89
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 03/12473-9; Floods increase the similarity of the abiotic water characteristics of the rivers with those of the surrounding floodplains and are the main factors that influence the ecosystem dynamics. The aim of this paper was to examine the alterations in abiotic characteristics of the Paranapanema River and three lateral lagoons with different degrees of connectivity to the river during the flood period. Samplings were performed twice a week during a three-month period. Water quality in the Camargo and Coqueiral lagoons, connected to the Paranapanema River, presented patterns of variation similar to those of the lotic ecosystem, evidenced by the principal component analysis. In Cavalos Lagoon, changes in water quality were observed in all the environments, such as a function of dilution after the water level increased and greater nutrients resulting from littoral plant decomposition after submersion. In conclusion, the marginal lagoons and river were influenced by two anthropogenic actions: water storage in a dam reservoir, which acted like a buffer against hydrological pulses, and the widening of the channel uniting Camargo Lagoon with the river, changing the connectivity level and causing an ever-greater similarity of the lagoon with the lotic system.

Parasitological diversity in non-human Primates at the Natural Park of the Lagoons of Cufada (Guinea-Bissau, West Africa)

Crespo, Maria Virgínia; Rosa, Fernanda; Mendes, L.
Fonte: Instituto Politécnico de Santarém Publicador: Instituto Politécnico de Santarém
Tipo: Conferência ou Objeto de Conferência
Publicado em 18/07/2004 ENG
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Apresentação em painel; A parasitological study on non-human primates was performed during a biodiversity study at the Natural Park of the Lagoons of Cufada (Guinea-Bissau, West Africa), on February-March 2001 and October- November 2002. The PRIMATES hosts observed were Cercopithecus mona campbelli (mona monkey), Chlorocebus aethiops sabeus (mangroove monkey), Papio cynocephalus papio (yellow baboon) e Procolobus badius temminckii (red colobus), which were caught by tradicional trapping. The helminths were collected after a decanting process and fixation in alcohol 70º. The morphobiometrical studies were performed on specimens clarified by lactofenol (NEMATODA, PENTASTOMIDA and ARTHROPODA) and stained by chloridrical alcoholic carmin (PLATYHELMINTHES). PHYLLA PLATYHELMINTHES (TREMATODA - Dicrocoelium hospes, Watsonius watsoni - and CESTODA – Bertiella studeri), NEMATODA (ENOPLIDA - Trichuris trichuria; SRONGYLIDA – Strongyloides fuelleborni, Ternidens deminuta, Oesophagostomum bifurcum, O. stephanostomum, Globocephalus longenucronatus, Pithecostrongylus sp., Hyostrongylus rubidus, ASCARIDIDA – Subulura distans; RHABDITIDA – Enterobius sp., and SPIRURIDA), PENTASTOMIDA (Armillifer armillatus) and ARTHROPODA (INSECTA – DIPTERA: first and second stages larvae of BRACHYCERA) were identified. Oesophagostomum stephanostomum and Hyostrongylus rubidus are new record for non-human primates from Guinea-Bissau. All the primates species were infected and NEMATODA was the most abundant and diverse parasitic group. The results obtained showed distinct diversity rates...

Benthic ecology of semi-natural coastal lagoons, in the Ria Formosa (Southern Portugal), Exposed to different water renewal regimes

Gamito, Sofia
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em /02/2006 ENG
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Several studies in semi-natural coastal lagoons in the Ria Formosa lagoonal system have been carried out. These man-made water reservoirs behave as small lagoons with one opening to the tidal channels, which may be intermittent. Because of their size, these reservoirs are ideal sites for ecological studies. Water quality and macrobenthic fauna were analysed in five water reservoirs. All reservoirs received the same incoming water through a tidal channel, but they differed in water renewal regime. Multidimensional Scaling (MDS) and Discriminant Analysis were used to evaluate the similarity among sites, stations and sampling occasions. Different levels of taxonomic resolution (family, large taxonomic groups and phylum level) were also evaluated. The separation of sites and stations became unclear using high taxonomic levels. Results from the multivariate analyses suggest a slight differentiation of the stations according to sampling occasion but a clear differentiation of the several water reservoirs. Some of the lagoons studied with low water renewal rates showed strong environmental variations. They were characterised by low diversity indexes and abundance of small-sized organisms. Other lagoons, with high water renewal rates, showed low environmental variation and well diversified and structured benthic communities. The main environmental factor that seems to affect the benthic communities was the variation in salinity between neap and spring tides...

Organic matter composition in the sediment of three Brazilian coastal lagoons: district of Macaé, Rio de Janeiro (Brazil)

Zink,Klaus-Gerhard; Furtado,André L. S.; Casper,Peter; Schwark,Lorenz
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2004 EN
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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.

Larvae and post-larvae of Penaeidae and Palaemonidae in coastal lagoons of the North of Rio de Janeiro (Macaé, RJ)

ALBERTONI,E. F.; PALMA-SILVA,C.; ESTEVES,F. A.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/1999 EN
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The northern part of the state of Rio de Janeiro shelters many coastal lagoons, located, mostly, in the "restinga" strip that stretches from the municipality of Macaé to the municipality of Quissamã. During 1995 and 1996 samplings were made aiming to verify the diversity and density of Natantia larvae in the Imboassica, Cabiúnas and Comprida lagoons. The monthly samples were taken with a 500 µ net, in horizontal drags from a boat. In Comprida lagoon no larvae of any family of these crustaceans were found. In Cabiúnas lagoon, the autumn was the season of the year with greatest relative abundance, the larvae belonging to only one genus: Macrobrachium. In Imboassica Lagoon samples were taken in two situations related to the variation of the water level and contact with sea water: horizontal boat dragging when the sandbar (the strip of sand that separates the lagoon from the sea) was closed, larvae of Macrobrachium sp. being found, and no seasonal variation being detected, and horizontal manual dragging with open and closed sandbar conditions, in a region close to the sandbar. With the sandbar open, larvae and post-larvae of Penaeus paulensis and P. brasiliensis were found, the greatest abundances being found in the months of April/96 and May/95.

The ichthyofauna of the marginal lagoons of the Sorocaba River, SP, Brazil: composition, abundance and effect of the anthropogenic actions

SMITH,W. S.; BARRELLA,W.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2000 EN
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The marginal lagoons of the Sorocaba River fulfil important functions in their lotic ecosystems and for its fish communities, providing shelter, food, and area for fish early stages of development. The lagoons are also an escape from the river pollution since the physical-chemical characteristics of their water are more stable than the river water. Nevertheless, these lagoons are under a series of impacts that contribute to reduce their diversity and stability such as water pollution, deforesting and river dumping. These impacts decrease habitat availability, and modify the fish community structure by reducing the number of species in the Sorocaba River, the floodplains and its marginal lagoons.

Aspects of the uptake of dissolved oxygen in Cabiúnas and Imboassica Lagoons (Macaé, RJ)

Brum,Paulo R.; Farjalla,Vinicius F.; Gonçalves Jr.,José F.; Santos,Anderson M. dos; Pôrto,Maurício T.; Vieira,Elisa D. R.; Ferreira,Flávia M.; Bianchini Jr.,Irineu
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1999 EN
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In this work, we describe qualitative and quantitative aspects of the cycling of detritus of aquatic macrophytes and carbohydrates in two coastal lagoons of the northeastern part of the State of Rio de Janeiro. Samples of water of the Imboassica and Cabiúnas lagoons were enriched with sucrose. Samples of water of the Cabiúnas lagoon were also utilized to arrange mineralization chambers with fragments of three species of aquatic macrophytes found in these lagoons (Typha domingensis, Potamogeton stenostachys and Nymphaea ampla). Following that, the bottles were aerated and incubated (in the laboratory) for a period of 8 days. The concentrations of dissolved oxygen, the pH, the electrical conductivity and the temperature were daily measured. The anaerobic processes were inhibited by periodical aeration of the bottles. The results suggested that the mineralization process in Imboassica lagoon was more efficient; in Cabiúnas lagoon the process of immobilization of the organic matter was dominant. In the short term, maximum oxygen uptake occurred in the mineralization of N. ampla, followed by the mineralization of P. stenostachys and of T. domingensis. However, it was estimated that in long term the mineralization of P. stenostachys showed a greater oxygen uptake.

Diet of the clupeid fish Platanichthys platana (Regan, 1917) in two different Brazilian coastal lagoons

Aguiaro,Talita; Castelo Branco,Christina Wyss; Verani,José Roberto; Caramaschi,Érica Pellegrini
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2003 EN
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Platanichthys platana is considered a constant species in both Cabiúnas and Imboassica lagoons that are characterised by different marine and freshwater inputs, and anthropogenic influences. The stomach content analysis of P. platana captured between July 1991 and July 1993 revealed filamentous algae, detritus, eggs of benthic invertebrates, larvae of chironomids and bivalves as the main food sources in Imboassica lagoon. Small-sized cladocerans, copepods and shrimp larvae were the prevailing items in Cabiúnas lagoon. Seasonal food variations were noted for the fishes of Imboassica lagoon. Diet differences were highlighted within specimens lesser than 40 mm standard length in Imboassica lagoon, and were related to the increase of marine influence due to artificial sand barrier openings. Dissimilarities among size classes in relation to invertebrate larvae consumption were observed in fishes from Cabiúnas lagoon.

Limnological patterns in northern pantanal lagoons

Bleich,Monica Elisa; Silveira,Roberto Moraes Lima; Nogueira,Flávia Maria Barros
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2009 EN
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The aim of this work was to correlate the limnological patterns recorded among ten lagoons in the northern part of the Pantanal of Mato Grosso with some aspects of the lagoons related to their physical and biological characteristics. Some lagoon characteristics, such as connection with the river and the presence of floating macrophytes were important to group similar lagoons into categories. Attempts were also made to determine which kind of the nutrients could be limiting phytoplankton productivity in the lagoons of the northern Pantanal. Data was collected in nine lagoons during the flooding stage in January 2004, and nutrient and chlorophyll a was followed in a tenth lagoon from June 2004 to October 2004. The phytoplankton biomass was significantly associated with the nitrogen concentration during the flooding and drought periods. All the studied lagoons were potentially limited by the nitrogen concentration with a strong negative relationship between the chlorophyll a biomass and ammonium concentration during the drought season. The drought season also had nearly three times more chlorophyll a biomass when compared to the flooding period.

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

Caliman,A.; Carneiro,LS.; Santangelo,JM.; Guariento,RD.; Pires,APF.; Suhett,AL.; Quesado,LB.; Scofield,V.; Fonte,ES.; Lopes,PM.; Sanches,LF.; Azevedo,FD.; Marinho,CC.; Bozelli,RL.; Esteves,FA.; Farjalla,VF.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2010 EN
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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...

Potential changes in bacterial metabolism associated with increased water temperature and nutrient inputs in tropical humic lagoons

Scofield, Vinicius; Jacques, Saulo M. S.; Guimarães, Jean R. D.; Farjalla, Vinicius F.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 15/04/2015 EN
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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...

Larvae and post-larvae of Penaeidae and Palaemonidae in coastal lagoons of the north of Rio de Janeiro (Macaé, RJ)

Albertoni, Edélti Faria; Palma-Silva, Cleber; Esteves, Francisco de Assis
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.28%
The northern part of the state of Rio de Janeiro shelters many coastal lagoons, located, mostly, i the “restinga” strip that stretches from the municipality of Macaé to the municipality of Quissamã During 1995 and 1996 samplings were made aiming to verify the diversity and density of Natanti larvae in the Imboassica, Cabiúnas and Comprida lagoons. The monthly samples were taken with 500 µ net, in horizontal drags from a boat. In Comprida lagoon no larvae of any family of these crus taceans were found. In Cabiúnas lagoon, the autumn was the season of the year with greatest rela tive abundance, the larvae belonging to only one genus: Macrobrachium. In Imboassica Lagoon sample were taken in two situations related to the variation of the water level and contact with sea water horizontal boat dragging when the sandbar (the strip of sand that separates the lagoon from the sea was closed, larvae of Macrobrachium sp. being found, and no seasonal variation being detected, an horizontal manual dragging with open and closed sandbar conditions, in a region close to the sandba With the sandbar open, larvae and post-larvae of Penaeus paulensis and P. brasiliensis were found the greatest abundances being found in the months of April/96 and May/95.

Avaliação da codisposição de resíduos de fossa e tanque sépticos em sistema de tratamento de esgoto composto por lagoas anaeróbias, facultativas e de maturação; Assesment of co-disposing of wastes from cesspool and septic tanks into wastewater treatment plant composed by anaerobic, facultative and maturation ponds

Haddad, Katia Bittar
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Engenharia do Meio Ambiente (EEC); Escola de Engenharia Civil - EEC (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Engenharia do Meio Ambiente (EEC); Escola de Engenharia Civil - EEC (RG)
Tipo: Dissertação Formato: application/pdf
POR
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The deficiency displayed by public basic sanitation systems in Brazil forces a major part of the population to seek individual alternatives to the final treatment and disposal of domestic septage such as septic tanks and rudimentary cesspools. Waste coming from such individual systems are, for the most part, discharged into Waste Water Treatment Plants (WWTPs), which are not designed to such end. Hence, we observe a decrease in the efficiency of sanitary waste treatment by WWTPs, which, in turn, leads to the pollution of water resources. Thus, the present study aimed to assess the impacts caused by waste discharge from cesspools and septic tanks into an anaerobic lagoon, followed by a facultative and maturation lagoons. Barro Preto WWTP has two modules of stabilizing lagoons (A and B). Module A was utilized as evidence. In other words, it did not receive cesspool and septic tank waste discharge. Module B rate was 0.20%. In order to force the system, the WWTP total flow was deviated to module B and the volumetric flow rate yielded was 0.05%. To characterize sludge yield in the Trindade-GO municipality, composite samples from six septage haulers were collected. Parameter analyses were: PH, Biological Oxygen Demand (BOD)...

An intercalibration exercise for benthic macrophyte indices across the Mediterranean Sea coastal lagoons

ORFANIDIS Sotiris; SFRISO A.; LAUGIER T; DEROLEZ Valerie; RAMFOS Alexios; NAKOU Konstantinia; BIRK Sebastian; ZAMPOUKAS NIKOLAOS; BONNE Wendy
Fonte: EURO-MEDITERRANEAN FEDERATION ON COASTAL LAGOONS & Italina Network for Lagoon Research Publicador: EURO-MEDITERRANEAN FEDERATION ON COASTAL LAGOONS & Italina Network for Lagoon Research
Tipo: Contributions to Conferences Formato: Printed
ENG
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Within the transitional waters macrophyte Mediterranean Geographical Intercalibration Group (MEDGIG) of the Water Framework Directive intercalibration, three countries (France, Greece, and Italy) compared their methodologies (Exclame, EEI-c, R-MaQI, respectively) for coastal lagoons. All methods classified soft bottom benthic macrophytes (angiosperms, seaweeds) in several sensitivity groups following the concept that “anthropogenic pressure” (stress) drives the ecosystem from a pristine state, where seagrasses are dominant, to a degraded state, where opportunistic species and phytoplankton are dominant. While Greece and Italy assessed the species abundance as coverage (%) in the laboratory, France assessed the species abundance as cover (%) in the field. A database consisting of 105 taxa abundance and pressure data from 55 shallow (depth=1-3m) and vegetated (cover >10%) sites (14 in France, 20 in Greece, 20 in Italy) belonging to meso-, poly- and euhaline (salinity >5‰) coastal lagoons, either confined or not confined, has been created. The 3 methods used a similar scale at biological (species), spatial (site) and temporal (one sampling per year during spring-summer) level, enabling a direct comparison of the 3 indices at biological community level. A common pressure index based on expert judgment was calculated. Multivariate analyses (MDS...

Determination of eutrophic areas in Mundaú/Manguaba lagoons, Alagoas-Brazil, through studies of the phytoplanktonic community

Melo-Magalhães,EM.; Medeiros,PRP.; Lira,MCA.; Koening,ML.; Moura,AN.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2009 EN
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Mundaú and Manguaba Lagoons (9° 34' 38"-9° 45' 30" S and 35° 44' 00"-35° 58' 13" W) are considered the largest and most productive ones in the state of Alagoas and were studied with the purpose of identifying the existence of anthropic impacts. Samples were collected at 8 stations, during low tide and flooding in rainy and dry periods, using the "Van Dorn" bottle and plankton net. In total, 155 taxons were identified, with special emphasis on Bacillariophyta and Cyanophyta divisions. The most abundant species in Mundaú Lagoon was Skeletonema cf. costatum, and in the Manguaba Lagoon, Cyclotella meneghiniana, Microcystis aeruginosa and Anabaena spiroides. The diversity ranged from 0.17 bits cell/L to 4.81 bits cell/L. The predominance of freshwater species (51%), evidenced higher influence of the limnetic flow on the two environments studied. The high values related to the phytoplanktonic density characterize the lagoons as strongly impacted environments, indicating the existence of eutrophic conditions in most of the studied stations.

Influence of lagoons size and prey availability on the wading birds (Ciconiiformes) in the upper Paraná river floodplain, Brazil

Gimenes,Márcio Rodrigo; Anjos,Luiz dos
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2006 EN
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The influence of lagoons size and prey availability on the Ciconiiformes in the upper Paraná river floodplain, Brazil, were analysed. The Ciconiiformes census was conducted quarterly in 2002, simultaneously to the fish census (gill nets and seining nets). There was strong relationship between the lagoons size and birds abundance, but modest relationship of lagoons size with the birds diversity and number of species. The presence of Ciconiiformes in the lagoons was better predicted by the fish density in seining nets than by the fish capture by unit of effort in gill nets. Except in the flood, there was strong relationship between the fishes density and birds relative abundance, and more modest relationship of the fishes density with birds diversity and number of species. The lagoon's size and prey availability were strong predictors of Ciconiiformes abundance and relative abundance, respectively. However, environmental variables not analysed probably could have significant influence in the determination of the birds diversity and number of species.

Comparative composition and dynamics of harmful dinoflagellates in Mediterranean salt marshes and nearby external marine waters

López-Flores, Rocio; Garcés, Esther; Boix, Daniel; Badosa, Anna; Brucet, Sandra; Masó, Mercedes; Quintana, Xavier D.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 530832 bytes; application/pdf
ENG
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12 pages, 7 figures, 1 table.-- Printed version published Dec 2006.; The taxonomic structure of phytoplankton populations in two Mediterranean coastal lagoons were compared with those of nearby marine waters (external waters). Mediterranean confined lagoons remain isolated for most the year and concentrate phytoplankton to a very high biomass. Coastal lagoons on the Mediterranean may, therefore, act as accumulators of neritic phytoplankton (including species related to harmful algal blooms). We examined whether coastal lagoons act as concentrators of marine toxic dinoflagellates during confinement periods, and the common environmental factors that favour growth of specific harmful species in the two ecosystems considered: coastal lagoons and external waters. An alternation between the dominance of diatoms and dinoflagellates was observed, coinciding with that described in Margalef's mandala, occurring in external waters as well as in coastal lagoons. Moreover, the temporal patter was different in the two ecosystems. Dinoflagellate species composition and their bloom period were highly variable in time and space, thus, species had to be analysed individually. Most of the dinoflagellate species found in this study were potentially harmful and high biomass producers. Harmful dinoflagellate species performed well in both...

Heterotrophic microbial activity and organic matter degradation in coastal lagoons of Colombia

Gocke,Klaus; Mancera Pineda,José Ernesto; Vallejo,Adriana
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2003 EN
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In this study we measured the community respiration and the bacterial respiration as part of the overall degradation process of organic material. Additionally, the turnover rates of the pools of dissolved free glucose and acetate as representatives of the fraction of easily degradable low molecular organic solutes were determined. The study was performed in several coastal lagoons of the "Outer Delta of the Río Magdalena" in northern Colombia. The lagoons can be separated into two groups: The first group contains highly productive brackish lagoons with chl a concentrations ranging from 62 - 130 µg/l. The second group consists of less productive freshwater lagoons with chl a between 5.5 - 19 µg/l. Turnover rates of glucose and acetate were very fast in the highly productive lagoons resulting in turnover times of less than 20 min for both compounds. In the less productive systems the cycling of glucose and acetate was much slower. Here the mean values of the turnover times were 2 hr for glucose and 1.5 hr for acetate. The rates of bacterial DNA-formation measured as thymidine incorporation differed significantly between both groups of lagoons, being very high (1.86 - 2.76 nmol/l/hr) in the highly productive and relatively low (0.073 - 0.55 nmol/l/hr) in the less productive group. Water column community respiration ranged between 122 and 16 µg C/l/hr with means of 88 µg C/l/hr in the highly and 19 µg C/l/hr in the less productive group. In the first group the mean values of the bacterial contribution to community respiration amounted to 37% and in the second group to 18%. The bacterial respiration was determined in an indirect way via bacterial biomass production and assuming a growth efficiency of 50%. It is discussed whether this relatively high growth efficiency allows reasonable results in both groups of lagoons.

Further remarks on the role of pro-thrombolites in the origin of coastal lagoons for Northwestern Mexico

Siqueiros Beltrones,David Alfaro; Hernández Almeida,Óscar Ubisha; Murillo Jiménez,Janette Magalli
Fonte: UAM, Unidad Iztapalapa, Publicador: UAM, Unidad Iztapalapa,
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
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Along the margins of coastal lagoons in Baja California Sur, Mexico, cyanobacteria-dominated communities form thick mats that eventually generate consolidated mud platforms or pro-thrombolites (unlithified thrombolites). Pro-thrombolite platforms grow seaward and form spits that alter water flow and promote sand deposition that develop into barriers, thus influencing coastal geomorphology, promoting lagoon formation. In this paper we provide evidences on the role of pro-thrombolites in the generation of coastal lagoons that includes different regions of NW Mexico where pro-thrombolite and/or thrombolithic platforms are common. In Bahía Magdalena, desiccating microbial mats are dominated by Microcoleus chthonoplastes Thuret ex Gomont and their remaining empty sheats occur together with lithified structures (thrombolites) cemented with micrite, considered of biotic origin. Previously proposed as a lacunar process, it is now suggested that pro-thrombolithic development leading to coastal lagoon formation actually occurs in non-lacunar environments with similar hidrological conditions. Likewise, this process is further enhanced once the coastal lagoon has been formed. We also suggest that the establishment of mangrove forests is indeed preceded by the formation of prothrombolithic platforms that provide a stabilized substrate for these plants in tropical and subtropical coastal lagoons.