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Sample records for catchment southeastern brazil

  1. Long-term evolution of denudational escarpments in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Cherem, Luis Felipe Soares; Varajão, Cesar Augusto C.; Braucher, Regis; Bourlés, Didier; Salgado, André Augusto R.; Varajão, Angélica C.

    2012-11-01

    Topographic relief in southeastern Brazil consists of a sequence of stepped surfaces that formed after the fragmentation of Gondwana during the Cretaceous, Tertiary and Quaternary tectonic pulses. This region is drained by four major rivers within four major river basins, with interfluves that contain denudational escarpments, fault escarpments and mountain ranges. This study presents an analysis of the long-term evolution of two denudational escarpments, the Cristiano Otoni and the São Geraldo steps, which divide the river basins of the São Francisco, Doce and Paraíba do Sul rivers in southeastern Brazil. Denudation rates were obtained through the measurement of mean concentrations of in situ produced cosmogenic 10Be in sand-sized fluvial quartz sediments collected from granitic terrains. The rates were calculated and compared with one another and correlated to the basin-scale mean relief, slope, area, and stream power. The mean denudation rates of the Cristiano Otoni and São Geraldo highlands are 8.77 (± 2.78) m My- 1 and 15.68 (± 4.53) m My- 1, respectively. The mean denudation rates of the Cristiano Otoni and São Geraldo escarpments are 17.50 (± 2.71) m My- 1 and 21.22 (± 4.24) m My- 1, respectively. The denudation rates of the catchments of highlands that drain toward the escarpments are similar to those of their respective highlands. The results demonstrate that relief and slope have similar positive control on the denudation rates for all of the samples despite their different geomorphic context and history of landscape evolution. The São Francisco River Basin is losing area to the Doce River Basin, which, in turn, is losing area to the Paraíba do Sul River Basin.

  2. The Rio Doce Orogeny, Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Neto, M. C. Campos; Figueiredo, M. C. H.

    1995-04-01

    The Neoproterozoic-Eopaleozoic superposed orogenic system of Southeastern Brazil, which was active during the Brasiliano-Pan-African Cycle during the assembly of this sector of the Gondwana Supercontinent, includes distinct terranes such as the Guanhães, Curitiba, Apiaí-Guaxupé and Serra do Mar microplates and the Juiz de Fora Thrust Belt. These orogenic systems also affected the reworked border of the São Francisco Craton. The collisional or ocean plate subduction-controlled "Brasiliano I" Orogeny was responsible for the generation of fold belts along the southeastern border of the São Francisco Craton, the accretion of different microplates and the formation of a magmatic arc associated with the roots of a northwestward trending thrust belt. The "Brasiliano I" evolution occurred during the Neoproterozoic and by 600 Ma was already in a post-orogenic stage in the Apiaí-Guaxupé Microplate, with the intrusion of rapakivi-like granitoids. The Rio Doce Orogeny is best characterized in the Serra do Mar Microplate by a magmatic arc, active between 590 and 570 Ma, with batholithic calc-alkaline plutonism exhibiting subduction zone components and a chemical zonation indicative of northwestward subduction. The collisional stage (560-530 Ma) accounted for the accretion of the Serra do Mar Microplate to the former orogenic domains. Anatexis of mostly metasediments producing peraluminous migmatites and granites, began at the calc-alkaline magmatic arc stage and culminated during crustal thickening associated with the northwesterly piling-up of large thrust slices. The post-collisional plutonism (520-480 Ma) is characterized by plutons and dikes of mainly alkali-calcic granitoids enriched in incompatible elements.

  3. Whistle comparison of four delphinid species in Southeastern Brazil.

    PubMed

    Lima, Isabela M S; Andrade, Luciana G; Bittencourt, Lis; Bisi, Tatiana L; Flach, Leonardo; Lailson-Brito, José; Azevedo, Alexandre F

    2016-05-01

    The present study evaluates variations in frequency and duration parameters of whistles of four dolphin species (Sotalia guianensis, Steno bredanensis, Stenella frontalis, and Tursiops truncatus), recorded in the Rio de Janeiro State Coast, Southeastern Brazil. A total of 487 whistles were analyzed. Acoustic parameters of the whistles were classified to species by discriminant function analysis. Overall classification score was 72.5%, with the highest classification score obtained for whistles of S. bredanensis and the lowest obtained for S. frontalis. Most differences were among S. bredanensis and S. guianensis, species that did not have their repertoires compared in other studies. PMID:27250196

  4. Lightning forecasting in southeastern Brazil using the WRF model

    NASA Astrophysics Data System (ADS)

    Zepka, G. S.; Pinto, O.; Saraiva, A. C. V.

    2014-01-01

    This paper introduces a lightning forecasting method called Potential Lightning Region (PLR), which is the probability of the occurrence of lightning over a region of interest. The PLR was calculated using a combination of meteorological variables obtained from high-resolution Weather Research and Forecasting (WRF) model simulations during the summer season in southeastern Brazil. The model parameters used in the PLR definition were: surface-based Convective Available Potential Energy (SBCAPE), Lifted Index (LI), K-Index (KI), average vertical velocity between 850 and 700 hPa (w), and integrated ice-mixing ratio from 700 to 500 hPa (QICE). Short-range runs of twelve non-severe thunderstorm cases were performed with the WRF model, using different convective and microphysical schemes. Through statistical evaluations, the WRF cloud parameterizations that best described the convective thunderstorms with lightning in southeastern Brazil were the combination of Grell-Devenyi and Thompson schemes. Two calculation methods were proposed: the Linear PLR and Normalized PLR. The difference between them is basically how they deal with the influence of lightning flashes over the WRF domain's grid points for the twelve thunderstorms analyzed. Three case studies were used to test both methods. A statistical evaluation lowering the spatial resolution of the WRF grid into larger areas was performed to study the behavior and accuracy of the PLR methods. The Normalized PLR presented the most suitable one, predicting flash occurrence appropriately.

  5. Influence of Catchment-Scale Military Land Use on Stream Physical and Organic Matter Variables in Small Southeastern Plains Catchments (USA)

    NASA Astrophysics Data System (ADS)

    Maloney, Kelly O.; Mulholland, Patrick J.; Feminella, Jack W.

    2005-05-01

    We conducted a 3-year study designed to examine the relationship between disturbance from military land use and stream physical and organic matter variables within 12 small (<5.5 km2) Southeastern Plains catchments at the Fort Benning Military Installation, Georgia, USA. Primary land-use categories were based on percentages of bare ground and road cover and nonforested land (grasslands, sparse vegetation, shrublands, fields) in catchments and natural catchments features, including soils (% sandy soils) and catchment size (area). We quantified stream flashiness (determined by slope of recession limbs of storm hydrographs), streambed instability (measured by relative changes in bed height over time), organic matter storage [coarse wood debris (CWD) relative abundance, benthic particulate organic matter (BPOM)] and stream-water dissolved organic carbon concentration (DOC). Stream flashiness was positively correlated with average storm magnitude and percent of the catchment with sandy soil, whereas streambed instability was related to percent of the catchment containing nonforested (disturbed) land. The proportions of in-stream CWD and sediment BPOM, and stream-water DOC were negatively related to the percent of bare ground and road cover in catchments. Collectively, our results suggest that the amount of catchment disturbance causing denuded vegetation and exposed, mobile soil is (1) a key terrestrial influence on stream geomorphology and hydrology and (2) a greater determinant of in-stream organic matter conditions than is natural geomorphic or topographic variation (catchment size, soil type) in these systems.

  6. Karyotype of three Lonchophylla species (Chiroptera, Phyllostomidae) from Southeastern Brazil.

    PubMed

    Almeida, Brunna; Novaes, Roberto Leonan Morim; Aguieiras, Marcia; Souza, Renan de França; Esbérard, Carlos Eduardo Lustosa; Geise, Lena

    2016-01-01

    Lonchophylla Thomas, 1903 is a Neotropical bat genus that comprises 12 species, with little cytogenetic information available. Here we present the description of the karyotype of three species collected in Southeastern Brazil. Lonchophylla bokermanni Sazima, Vizotto & Taddei, 1978, Lonchophylla dekeyseri Taddei, Vizotto & Sazima, 1983, and Lonchophylla peracchii Dias, Moratelli & Esberard, 2013 showed the same diploid number 2n = 28 and the same autosomal fundamental number FNa = 50, in both Lonchophylla bokermanni and Lonchophylla peracchii. We observed that the karyotypes were also cytogenetically similar when we compared the studied species with other species within the same genus. It is therefore not possible to differentiate the species using only karyotypes with conventional staining. However, this information increases the knowledge of the genus and can be one more important character for a better phylogenetic comprehension of this taxon. PMID:27186341

  7. Karyotype of three Lonchophylla species (Chiroptera, Phyllostomidae) from Southeastern Brazil

    PubMed Central

    Almeida, Brunna; Novaes, Roberto Leonan Morim; Aguieiras, Marcia; Souza, Renan de França; Esbérard, Carlos Eduardo Lustosa; Geise, Lena

    2016-01-01

    Abstract Lonchophylla Thomas, 1903 is a Neotropical bat genus that comprises 12 species, with little cytogenetic information available. Here we present the description of the karyotype of three species collected in Southeastern Brazil. Lonchophylla bokermanni Sazima, Vizotto & Taddei, 1978, Lonchophylla dekeyseri Taddei, Vizotto & Sazima, 1983, and Lonchophylla peracchii Dias, Moratelli & Esberard, 2013 showed the same diploid number 2n = 28 and the same autosomal fundamental number FNa = 50, in both Lonchophylla bokermanni and Lonchophylla peracchii. We observed that the karyotypes were also cytogenetically similar when we compared the studied species with other species within the same genus. It is therefore not possible to differentiate the species using only karyotypes with conventional staining. However, this information increases the knowledge of the genus and can be one more important character for a better phylogenetic comprehension of this taxon. PMID:27186341

  8. Vegetation structure in cerrado physiognomies in south-eastern Brazil.

    PubMed

    Batalha, M A; Mantovani, W; de Mesquita Júnior, H N

    2001-08-01

    We studied three cerrado physiognomies (campo cerrado, a savanna woodland; cerrado sensu stricto, a woodland; and cerradão, a tall woodland) in a reserve with 1,225 ha, in Santa Rita do Passa-Quatro (21 degrees 36-38'S and 47 degrees 36-39'W), São Paulo State, South-eastern Brazil, to compare plant communities structure. As descriptors of the vegetation structure, we used richness, density, basal area, cylindrical volume, and diversity. Ten 40 m2 quadrats were placed randomly in each physiognomy, in which we sampled the woody plants with stem diameter equal or larger than 1 cm (woody component), and ten 2.5 m2 quadrats, in which we sampled the woody plants with stem diameter smaller than 1 cm and all the non-woody individuals (herbaceous component). In the woody component, we found significant differences among the physiognomies for richness, density and cylindrical volume. Cylindrical volume increased from campo cerrado to cerradão, but richness and density were higher in cerrado sensu stricto. In the herbaceous component, we detected differences for all variables, which were higher in the savanna physiognomies, campo cerrado and cerrado sensu stricto, than in the forest physiognomy, cerradão. Cylindrical volume was the best variable to distinguish the physiognomies. Floristic similarity followed the campo cerrado-cerrado sensu stricto-cerradão gradient, and beta diversity was higher in the herbaceous component. PMID:11706576

  9. Updating the Seismic Hazard Determination in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Franca, G. S.; Algarte, K. T.

    2012-12-01

    This job presents an update of research by Berrocal in 1996 in the determination of seismic hazard for the Southeast of Brazil, based on the earthquake catalog compiled at the Instituto de Astronomia e Geofisica, Universidade de Sao Paulo and bulletin of Seismological Observatory, Universidade de Brasilia, during the period between 1767 until May 2012. The southeastern Brazil has a level of seismic activity is considered low, typical of intraplate regions. Our database has a total of 3726 events, however 1242 events do not have the magnitude estimated, 1638 events are between magnitudes 0.1 to 1.9 and from 2.0 to 3.9 are 819 events. The largest earthquake in the region occurred on February 28, 1955 with magnitude 6.1 mb (Assumpção, 2000), with its epicenter about 400 km from the coast, this was felt in small cities, especially in Espirito Santo State. The intensity VIII-IX MM was estimated by Berrocal et al. (1984). The database also has four events with magnitude above 5.0 mb in the region that occurred during the past 215 years and a little more than a twenty earthquakes with magnitude between 4.0 and 5.0 mb. Instrumental data are available since the 1970s when the station network was installed in Brasilia. Several other short-period vertical stations have been installed in the region. We used data from the same area defined in the previous survey, located between parallels 15S-32S degree and longitudes 35W-52W degree. It contains the most developed area of Brazil, and the major cities and industrial centers of the country (São Paulo, Rio de Janeiro and Belo Horizonte). Major engineering works, hydroelectric and nuclear power plant (Angra dos Reis) are also in this area. Therefore, the results can be applied to the planning and construction of large engineering within that region. With GIS and seismology tools was calculated relative frequency/magnitude for earthquakes mb > 3.0, the value of b with the maximum likelihood method, and so curves of recurrence was

  10. The Path towards Endangered Species: Prehistoric Fisheries in Southeastern Brazil

    PubMed Central

    Lopes, Mariana Samôr; Bertucci, Thayse Cristina Pereira; Rapagnã, Luciano; Tubino, Rafael de Almeida; Monteiro-Neto, Cassiano; Tomas, Acácio Ribeiro Gomes; Tenório, Maria Cristina; Lima, Tânia; Souza, Rosa; Carrillo-Briceño, Jorge Domingo; Haimovici, Manuel; Macario, Kita; Carvalho, Carla; Aguilera Socorro, Orangel

    2016-01-01

    Brazilian shellmounds are archaeological sites with a high concentration of marine faunal remains. There are more than 2000 sites along the coast of Brazil that range in age from 8,720 to 985 cal BP. Here, we studied the ichthyoarchaeological remains (i.e., cranial/postcranial bones, otoliths, and teeth, among others) at 13 shellmounds on the southern coast of the state of Rio de Janeiro, which are located in coastal landscapes, including a sandy plain with coastal lagoons, rocky islands, islets and rocky bays. We identified patterns of similarity between shellmounds based on fish diversity, the ages of the assemblages, littoral geomorphology and prehistoric fisheries. Our new radiocarbon dating, based on otolith samples, was used for fishery characterization over time. A taxonomical study of the ichthyoarchaeological remains includes a diversity of 97 marine species, representing 37% of all modern species (i.e., 265 spp.) that have been documented along the coast of Rio de Janeiro state. This high fish diversity recovered from the shellmounds is clear evidence of well-developed prehistoric fishery activity that targeted sharks, rays and finfishes in a productive area influenced by coastal marine upwelling. The presence of adult and neonate shark, especially oceanic species, is here interpreted as evidence of prehistoric fisheries capacity for exploitation and possibly overexploitation in nursery areas. Various tools and strategies were used to capture finfish in seasonal fisheries, over rocky reef bottoms and in sandy littoral environments. Massive catches of whitemouth croaker, main target dermersal species of South Atlantic coast, show evidence of a reduction in body size of approximately 28% compared with modern fisheries. Fishery activity involving vulnerable species, especially in nursery areas, could mark the beginning of fish depletion along the southeastern Brazilian coast and the collapse of natural fish populations. PMID:27355355

  11. The Path towards Endangered Species: Prehistoric Fisheries in Southeastern Brazil.

    PubMed

    Lopes, Mariana Samôr; Bertucci, Thayse Cristina Pereira; Rapagnã, Luciano; Tubino, Rafael de Almeida; Monteiro-Neto, Cassiano; Tomas, Acácio Ribeiro Gomes; Tenório, Maria Cristina; Lima, Tânia; Souza, Rosa; Carrillo-Briceño, Jorge Domingo; Haimovici, Manuel; Macario, Kita; Carvalho, Carla; Aguilera Socorro, Orangel

    2016-01-01

    Brazilian shellmounds are archaeological sites with a high concentration of marine faunal remains. There are more than 2000 sites along the coast of Brazil that range in age from 8,720 to 985 cal BP. Here, we studied the ichthyoarchaeological remains (i.e., cranial/postcranial bones, otoliths, and teeth, among others) at 13 shellmounds on the southern coast of the state of Rio de Janeiro, which are located in coastal landscapes, including a sandy plain with coastal lagoons, rocky islands, islets and rocky bays. We identified patterns of similarity between shellmounds based on fish diversity, the ages of the assemblages, littoral geomorphology and prehistoric fisheries. Our new radiocarbon dating, based on otolith samples, was used for fishery characterization over time. A taxonomical study of the ichthyoarchaeological remains includes a diversity of 97 marine species, representing 37% of all modern species (i.e., 265 spp.) that have been documented along the coast of Rio de Janeiro state. This high fish diversity recovered from the shellmounds is clear evidence of well-developed prehistoric fishery activity that targeted sharks, rays and finfishes in a productive area influenced by coastal marine upwelling. The presence of adult and neonate shark, especially oceanic species, is here interpreted as evidence of prehistoric fisheries capacity for exploitation and possibly overexploitation in nursery areas. Various tools and strategies were used to capture finfish in seasonal fisheries, over rocky reef bottoms and in sandy littoral environments. Massive catches of whitemouth croaker, main target dermersal species of South Atlantic coast, show evidence of a reduction in body size of approximately 28% compared with modern fisheries. Fishery activity involving vulnerable species, especially in nursery areas, could mark the beginning of fish depletion along the southeastern Brazilian coast and the collapse of natural fish populations. PMID:27355355

  12. Long-term Lake Evaporation Measurements in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Dias, N. L.; Cancelli, D. M.

    2007-05-01

    We report here for the first time the results of a long-term (37 months) campaign of lake evaporation measurements with the eddy-covariance (EC) method. The measurements were made at Furnas Lake, a large lake (1440 km2) in Southeastern Brazil (20° 44'S, 45° 58'W and 771.8 m ASL). Mean and maximum depths at the Maximum Normal Operating Level are 13 m and 90 m respectively. Taking advantage of a long drought during 2000--2001, a large metal tower was erected over the lake's dry bed. After the water level recovered, we were left with a stable platform for performing EC measurements in one of the lake's many basins. Fetch conditions over the prevailing wind directions were excellent (1000 m from the North, and more than 3000 m from the East), with the closest land at 420 m (from NE) and 440 m (from SW). Measurements included hourly means of water surface temperature, air temperature, specific humidity, downwelling solar radiation, net radiation, wind speed, and wind direction. 10-Hz eddy covariance measurements were made of turbulent fluctuations of 3 wind components, sonic virtual temperature, air temperature (with a fine-wire thermocouple) and of fluctuating specific humidity with a specially adapted capacitive hygrometer. The validation of this sensor to measure latent heat fluxes at high frequency was made on intensive field campaigns that deployed state-of-the art Ultra-Violet and Infra-Red fast-response hygrometers. Our data analysis indicates that atmospheric stability can be far from neutral, and that it plays a very important role in the mass-transfer and heat-transfer equations for the water vapor and sensible heat fluxes. We have also found that significantly different scalar roughenesses for water vapor and for sensible heat were necessary to calibrate properly the Monin-Obukhov Similarity Theory (MOST)-based transfer equations. Due to these differences, gradient-based Bowen ratios (as usually applied in the Energy Budget Bowen Ratio method in the absence

  13. A vulnerability analysis for a drought vulnerable catchment in South-Eastern Austria

    NASA Astrophysics Data System (ADS)

    Hohmann, Clara; Kirchengast, Gottfried; Birk, Steffen

    2016-04-01

    To detect uncertainties and thresholds in a drought vulnerable region we focus on a typical river catchment of the Austrian South-Eastern Alpine forelands with good data availability, the Raab valley. This mid-latitude region in the south-east of the Austrian state Styria (˜ 47° N, ˜ 16° E) exhibits a strong temperature increase over the last decades. Especially the mean summer temperatures (June to August) show a strong increase (˜ 0.7 °C per decade) over the last decades (1971 - 2015) (Kabas et al., Meteorol. Z. 20, 277-289, 2011; pers. comm., 2015). The Styrian Raab valley, with a catchment size of 986 km2, has already struggled with drought periods (e.g., summers of 1992, 2001 and 2003). Thus, it is important to know what happens if warm and dry periods occur more frequently. Therefore we analyze which sensitivities and related uncertainties exist, which thresholds might be crossed, and what the effects on the different components of the water balance equation are, in particular on runoff, soil moisture, groundwater recharge, and evapotranspiration. We use the mainly physics-based hydrological Water Flow and Balance Simulation Model (WaSiM), developed at ETH Zurich (Schulla, Diss., ETH Zurich, CH, 1997). The model is well established and widely used for hydrological modeling at a diversity of spatial and temporal resolutions. We choose a model set up which is as simple as possible but as complex as necessary to perform sensitivity studies on uncertainties and thresholds in the context of climate change. In order to assess the model performance under a wide range of conditions, the calibration and validation is performed with a split sample for dry and wet periods. With the calibrated and validated model we perform a low-flow vulnerability analysis ("stress test"), with focus on drought-related conditions. Therefore we simulate changes in weather and climate (e.g., 20% and 50% less precipitation, 2 °C and 5 °C higher temperature), changes in land use and

  14. A new species of the genus Alterosa (Trichoptera: Philopotaminae) from Southeastern Brazil.

    PubMed

    Jardim, Gabriela Abrantes; Dumas, Leandro Lourenço

    2012-06-01

    Philopotamidae is a large caddisfly family with 20 extant genera comprising about 1000 described species worldwide. Alterosa contains 22 described species distributed in South and Southeastern Brazil. Adults of the genus are very similar in general structure, but are remarkable for their wide variation in male genitalic morphology. The specimens were collected with Pennsylvania light traps and preserved in 80% ethanol. Alterosa nessimiani sp. nov. is described and figured from male specimens collected in streams of Rio de Janeiro state, Southeastern Brazil. The new species is closely related to A. jordaensis Blahnik 2005, from which it can be distinguished by the presence of two spines on the intermediate appendages and by the shape of tergum X. PMID:23894930

  15. Haplotype diversity in mitochondrial DNA hypervariable region in a population of southeastern Brazil.

    PubMed

    Fridman, C; Gonzalez, R S; Pereira, A C; Cardena, M M S G

    2014-07-01

    Brazilian population derives from Native Amerindians, Europeans, and Africans. Southeastern Brazil is the most populous region of the country. The present study intended to characterize the maternal genetic ancestry of 290 individuals from southeastern (Brazil) population. Thus, we made the sequencing of the three hypervariable regions (HV1, HV2, and HV3) of the mitochondrial DNA (mtDNA). The statistical analyses were made using Arlequin software, and the median-joining haplotype networks were generated using Network software. The analysis of three hypervariable regios showed 230 (79.3 %) unique haplotypes and the most common haplotype was "263G" carried by 12 (4.1 %) individuals. The strikingly high variability generated by intense gene flow is mirrored in a high sequence diversity (0.9966 ± 0.0010), and the probability of two random individuals showing identical mtDNA haplotypes were 0.0068. The analysis of haplogroup distribution revealed that 36.9 % (n = 107) presented Amerindian haplogroups, 35.2 % (n = 102) presented African haplogroups, 27.6 % (n = 80) presented European haplogroups, and one (0.3 %) individual presented East Asian haplogroup, evidencing that the southeastern population is extremely heterogeneous and the coexistence of matrilineal lineages with three different phylogeographic origins. The genetic diversity found in the mtDNA control region in the southeastern Brazilian population reinforces the importance of increased national database in order to be important and informative in forensic cases. PMID:24846100

  16. Hantavirus Pulmonary Syndrome, Central Plateau, Southeastern, and Southern Brazil

    PubMed Central

    Moreli, Marcos L.; de Sousa, Ricardo L.M.; Borges, Alessandra A.; de Figueiredo, Glauciane G.; Machado, Alex M.; Bisordi, Ivani; Nagasse-Sugahara, Teresa K.; Suzuki, Akemi; Pereira, Luiz E.; de Souza, Renato P.; de Souza, Luiza T.M.; Braconi, Carla T.; Harsi, Charlotte M.; de Andrade Zanotto, Paolo M.

    2009-01-01

    Hantavirus pulmonary syndrome (HPS) is an increasing health problem in Brazil because of encroachment of sprawling urban, agricultural, and cattle-raising areas into habitats of subfamily Sigmodontinae rodents, which serve as hantavirus reservoirs. From 1993 through June 2007, a total of 884 cases of HPS were reported in Brazil (case-fatality rate 39%). To better understand this emerging disease, we collected 89 human serum samples and 68 rodent lung samples containing antibodies to hantavirus from a 2,500-km-wide area in Brazil. RNA was isolated from human samples and rodent tissues and subjected to reverse transcription–PCR. Partial sequences of nucleocapsid protein and glycoprotein genes from 22 human and 16 rodent sources indicated only Araraquara virus and Juquitiba virus lineages. The case-fatality rate of HPS was higher in the area with Araraquara virus. This virus, which may be the most virulent hantavirus in Brazil, was associated with areas that have had greater anthropogenic changes. PMID:19331732

  17. Hantavirus pulmonary syndrome, central plateau, southeastern, and southern Brazil.

    PubMed

    Figueiredo, Luiz T M; Moreli, Marcos L; de-Sousa, Ricardo L M; Borges, Alessandra A; de-Figueiredo, Glauciane G; Machado, Alex M; Bisordi, Ivani; Nagasse-Sugahara, Teresa K; Suzuki, Akemi; Pereira, Luiz E; de-Souza, Renato P; de-Souza, Luiza T M; Braconi, Carla T; Harsi, Charlotte M; de-Andrade-Zanotto, Paolo M

    2009-04-01

    Hantavirus pulmonary syndrome (HPS) is an increasing health problem in Brazil because of encroachment of sprawling urban, agricultural, and cattle-raising areas into habitats of subfamily Sigmodontinae rodents, which serve as hantavirus reservoirs. From 1993 through June 2007, a total of 884 cases of HPS were reported in Brazil (case-fatality rate 39%). To better understand this emerging disease, we collected 89 human serum samples and 68 rodent lung samples containing antibodies to hantavirus from a 2,500-km-wide area in Brazil. RNA was isolated from human samples and rodent tissues and subjected to reverse transcription-PCR. Partial sequences of nucleocapsid protein and glycoprotein genes from 22 human and 16 rodent sources indicated only Araraquara virus and Juquitiba virus lineages. The case-fatality rate of HPS was higher in the area with Araraquara virus. This virus, which may be the most virulent hantavirus in Brazil, was associated with areas that have had greater anthropogenic changes. PMID:19331732

  18. Evidence of Dry and Cold Climatic Conditions at Glacial Times in Tropical Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Behling, Hermann; Lichte, Martin

    1997-11-01

    Last-glacial paleoenvironments have been reconstructed from a pollen and charcoal record analyzed in organic sediments and dated between ca. 18,000 and >48,000 14C yr B.P. The site is located near the village Catas Altas in the lower highland region of southeastern Brazil. The last-glacial landscape was covered by extensive areas of subtropical grasslands and small areas of gallery forests along the rivers, where tropical semideciduous forests and cerrado ecosystems exist today. The subtropical gallery forests were composed of Araucariaforest trees such as Araucaria angustifolia, Podocarpus, Drimys, Ilex,and Symplocos.Paleofires were frequent. The record indicates that subtropical grassland vegetation, which today is found in patches on the highlands in southern Brazil (especially in the state of Santa Catarina), expanded from southern Brazil to southeastern Brazil, over a distance of more than 750 km, from latitudes of about 28° S to at least 20° S. The completely different last-glacial environment, in comparison to the present-day environment, reflects a dry and cold climate with strong frosts during the winter months. Temperatures of 5°-7°C below those of the present are inferred for the last glaciation.

  19. PROJECT BLUE: An Operational Oceanography program in the Southeastern Brazil.

    NASA Astrophysics Data System (ADS)

    Alves dos Santos, Francisco; da Rocha Fragoso, Maurício; Maturo Marques da Cruz, Leonardo; de Castro Pellegrini, Julio Augusto; de Freitas Assad, Luiz Paulo; Landau, Luiz; Adissi, Flávia

    2013-04-01

    The beginning of 2013 will mark the start for the Project BLUE, one of the greatest efforts in operational oceanography ever proposed in Brazil. The region of interest is located in the continental shelf break between Cabo Frio (23°S) and Floriananópolis Island (28°S). The region is dominated by the Brazil Current system, formed by the Brazil Current, carrying Tropical Water southward from surface down to 400-500 meters and the Intermediate Counter Current, flowing northward in the interface of the South Atlantic Central Water and the Antarctic Intermediate Water. In situ data and operational forecasts efforts in this oil rich region are still few and disperse. Nevertheless, the constant increase of offshore operations is followed by the necessity of both a baseline study and a systematic data collection. All project structure is aimed at optimizing real-time data collection and displaying. Project BLUE is formed by 4 modules: (1) In situ data collection will be performed by 5 gliders, 108 surface drifters and 36 subsurface profiling floats. (2) Remote Sensing module count on a local receiving antenna to provide operational information of Sea Surface Temperature, Height and Ocean Color. (3) Numerical Modelling module aims, initially, to implement a regional grid for long climatological runs, followed by an operational run, with assimilation of the data generated by the first module. One of the great concerns of the Project BLUE is to turn public all collected data, allowing for a greater number of researchers to access the data and, consequently, improving the knowledge on the region. For that purpose, there is an specific module (4) Data displaying focused on easing the access to the data via web services. It is expected, by the end of the first three years, to have a systematic data collection system, a well adapted assimilation scheme and an operational forecast model for the Santos Basin, providing reliable information for offshore operations and emergency

  20. Low water quality in tropical fishponds in southeastern Brazil.

    PubMed

    Costa, Simone M; Appel, Eleonora; Macedo, Carla F; Huszar, Vera L M

    2014-09-01

    Expansion of aquaculture around the world has heavily impacted the environment. Because fertilizers are needed to raise fish, one of the main impacts is eutrophication, which lowers water quality and increases the frequency of algal blooms, mostly cyanobacteria. To evaluate whether the water quality in 30 fishponds in southeastern Brazilian met the requirements of Brazilian legislation, we analyzed biotic and abiotic water conditions. We expected that the high nutrient levels due to fertilization would cause low water quality. We also analyzed cyanotoxins in seston and fish muscle in some systems where cyanobacteria were dominant. The fishponds ranged from eutrophic and hypereutrophic with high phytoplankton biomass. Although cyanobacteria were dominant in most of the systems, cyanotoxins occurred in low concentrations, possibly because only two of the 12 dominant species were potential producers of microcystins. The high phosphorus concentrations caused the low water quality by increasing cyanobacteria, chlorophyll-a, turbidity, and thermotolerant coliforms, and by depleting dissolved oxygen. We found that all the 30 systems were inappropriate for fish culture, according to Brazilian legislation, based on at least one of the parameters measured. Furthermore, there was not any single system in the water-quality thresholds, according to the Brazilian legislation, to grow fish. Our findings indicate the need for better management to minimize the impacts of eutrophication in fishponds, in addition to a rigorous control to guarantee good food. PMID:25211104

  1. Rickettsia amblyommii infecting Amblyomma sculptum in endemic spotted fever area from southeastern Brazil.

    PubMed

    Nunes, Emília de Carvalho; Vizzoni, Vinicius Figueiredo; Navarro, Daniel Leal; Iani, Felipe Campos de Melo; Durães, Liliane Silva; Daemon, Erik; Soares, Carlos Augusto Gomes; Gazeta, Gilberto Salles

    2015-12-01

    The Rickettsia bacteria include the aetiological agents for the human spotted fever (SF) disease. In the present study, a SF group Rickettsia amblyommii related bacterium was detected in a field collected Amblyomma sculptum (Amblyomma cajennense species complex) tick from a Brazilian SF endemic site in southeastern Brazil, in the municipality of Juiz de Fora, state of Minas Gerais. Genetic analysis based on genes ompA,ompB and htrA showed that the detected strain, named R. amblyommii str. JF, is related to the species R. amblyommii. PMID:26676317

  2. Finding Aedes aegypti in a natural breeding site in an urban zone, Sao Paulo, Southeastern Brazil

    PubMed Central

    Lima-Camara, Tamara Nunes; Urbinatti, Paulo Roberto; Chiaravalloti-Neto, Francisco

    2016-01-01

    ABSTRACT This is the description of how nine Aedes aegypti larvae were found in a natural breeding site in the Pinheiros neighborhood, city of Sao Paulo, SP, Southeastern Brazil. The record was conducted in December 2014, during an entomological surveillance program of dengue virus vectors, with an active search of potential breeding sites, either artificial or natural. Finding Ae. aegypti larvae in a tree hole shows this species’ ability to use both artificial and natural environments as breeding sites and habitats, which points towards the importance of maintaining continuous surveillance on this mosquito in all kinds of water-holding containers. PMID:26982959

  3. Seasonal diet shifts of seven fish species in an Atlantic rainforest stream in Southeastern Brazil.

    PubMed

    Deus, C P; Petrere-Junior, M

    2003-11-01

    We analyzed the stomach contents of 116 individuals belonging to seven fishes species in order to investigate seasonal changes in feeding strategy and how trophic interactions between species affect community structure in an Atlantic rainforest stream in Southeastern Brazil. Oligosarcus hepsetus and Pimelodus sp. consumed fewer items during the winter. Phalloceros caudimaculatus switched feeding habits from detritus during summer to algae during winter. These examples are related to variations in food availability and species feeding selectivity. The highest diet overlap values, for most species, as measured using Schoener's index, were observed in summer, along with a species tendency to be more generalist. Feeding pattern variation may influence the fish community structure. PMID:15029369

  4. Effective gamma-ray doses due to natural radiation from soils of southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Silveira, M. A. G.; Medina, N. H.; Moreira, R. H.; Bellini, B. S.; Aguiar, V. A. P.

    2010-08-01

    We have used gamma-ray spectrometry to study the distribution of natural radiation from soils of southeastern Brazil: Billings reservoir, Sa~o Bernardo do Campo Parks, Diadema Parks, Interlagos region, Sa~o Paulo, and soil from Sa~o Paulo and Rio de Janeiro beaches. In most of the regions studied we have found that the dose due the external exposure to gamma-rays, proceeding from natural terrestrial elements, are between the values 0.3 and 0.6 mSv/year, established by the United Nations Scientific Committee on the Effects of Atomic Radiation.

  5. Effective gamma-ray doses due to natural radiation from soils of southeastern Brazil

    SciTech Connect

    Silveira, M. A. G.; Moreira, R. H.; Bellini, B. S.; Medina, N. H.; Aguiar, V. A. P.

    2010-08-04

    We have used gamma-ray spectrometry to study the distribution of natural radiation from soils of southeastern Brazil: Billings reservoir, Sao Bernardo do Campo Parks, Diadema Parks, Interlagos region, Sao Paulo, and soil from Sao Paulo and Rio de Janeiro beaches. In most of the regions studied we have found that the dose due the external exposure to gamma-rays, proceeding from natural terrestrial elements, are between the values 0.3 and 0.6 mSv/year, established by the United Nations Scientific Committee on the Effects of Atomic Radiation.

  6. The intracloud/cloud-to-ground lightning ratio in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    de Souza, P. E.; Pinto, O., Jr.; Pinto, I. R. C. A.; Ferreira, N. J.; dos Santos, A. F.

    2009-02-01

    The intracloud to cloud-to-ground lightning flash ratio ( Z) has been estimated for the first time in Southeastern Brazil and in the tropical region using the Lightning Imaging Sensor (LIS) and Brazilian lightning detection network (BrasilDat) lightning data obtained from 1999 to 2005. Geographical variations of Z and their relation to elevation, latitude, precipitation, total lightning density and percentage of positive CG lightning will be discussed. Daily variations of Z will also be presented. The results suggest that Z values are similar to studies outside the tropics and that are influenced by orographic features.

  7. Assessment of Changes in Blocking Activity Over Southeastern Brazil Under Climate Change Scenarios

    NASA Astrophysics Data System (ADS)

    Ferraz, S. E.; Pedroso, D.; Nascimento, E. D.; Da Rocha, R.; Ambrizzi, T.

    2013-05-01

    One of the main current efforts of the climate community is to investigate the impact of projected global climate change scenarios upon atmospheric circulations on the regional scale. Projections of rainfall anomalies represent a key aspect for assessing regional impacts of climate change on important human activities such as the civil defense, agriculture, and power generation. Given the points above, the present research aims at assessing possible alterations associated with distinct climate change scenarios in the regime of one atmospheric processes that influence the precipitation distribution and modulation over southeastern Brazil: atmospheric blocking. Objectives The objectives are determine an updated climatology of blocking activity over southeastern Brazil, which will serve as the current state of the atmosphere regarding these two weather systems over the region of interest and to evaluate the modification in the frequency and/or strength blocking system in southeastern Brazil given distinct projected climate change scenarios, and to examine how this modification may affect the frequency of heavy rain and drought events in that region; Data The data to be used include for updating the current climatology of blocking: three-dimensional daily atmospheric fields obtained from the NCEP/NCAR Reanalysis (Kalnay et al. 1996) and meteorological fields obtained from distinct climate change scenarios made available by the IPCC. To update the climatology of blocking, objective criteria are necessary to detect (and track) such systems from the NCEP/NCAR Reanalysis data for southeastern South America. For blocking systems, anomalies in the 500hPa geopotential heights will be used, following Tibaldi et al. (1994) and Nascimento and Ambrizzi (2002) approach. References Douglas, M. W., and J. C. Leal, 2003: Summertime surges over the Gulf of California: aspects of their climatology, mean structure, and evolution from radiosonde, NCEP Reanalysis, and rainfall data. Wea

  8. Two new species of the sharpshooter genus Oragua Melichar, 1926 from Southeastern Brazil (Hemiptera: Cicadellidae: Cicadellini).

    PubMed

    Mejdalani, Gabriel; Silva, Cristiane M F Da; Takiya, Daniela M

    2016-01-01

    Two very similar new species of Oragua Melichar, 1926, O. linnavuorii sp. nov. and O. flavolineata sp. nov., are described and illustrated from the Atlantic Forest of Southeastern Brazil (Mantiqueira mountain range). The new species share the presence of a large dentiform process located posteroventrally on the male pygofer, a unique feature within the genus. They can be distinguished from each other by the paraphyses with a pair of elongate, slender asymmetrical rami in O. linnavuorii and with two pairs of short, spiniform apical processes in O. flavolineata. The male of O. linnavuorii is macropterous but the female is submacropterous and thus smaller than the former when specimens are measured from the apex of the crown to the tips of the forewings at rest. The female of O. flavolineata is not known. Male holotypes are deposited in DZRJ. A key to males of the five Oragua species recorded from Southeastern Brazil is provided [O. maculifera Young, 1977, O. discoidula (Osborn, 1926), O. triplehorni Young, 1977, O. linnavuorii, and O. flavolineata]. The superficially similar genera Oragua and Aguana Melichar, 1926 are briefly compared. PMID:27395683

  9. Multiple determinants of anuran richness and occurrence in an agricultural region in South-eastern Brazil.

    PubMed

    Prado, Vitor H M; Rossa-Feres, Denise de C

    2014-04-01

    In agricultural landscapes, studies that identify factors driving species richness and occupancy are important because they can guide farmers to use conservation practices that minimize species loss. In this context, anurans are threatened by habitat loss because they depend on the characteristics of both local water bodies and adjacent landscapes. We used a model selection approach to evaluate the influence of local and landscape variables in determining anuran species richness and occurrence in 40 freshwater bodies in a heavily deforested region of semideciduous Atlantic Forest in southeastern Brazil. Our aim was to develop recommendations for conservation of anuran communities in rural areas. Pond hydroperiod and area were the most important variables for explaining anuran species richness and occupancy, with greatest species richness being found in water bodies with intermediate hydroperiod and area. Other important variables that reflected individual species occupancies were the number of vegetation types and pond isolation. In addition, recent studies evidenced that water bodies near forest fragments have higher anuran abundance or diversity. In conclusion, we suggest the maintenance of semi-permanent ponds, isolated from large rivers or reservoirs and near forest fragments, as an effective strategy to conserve anuran fauna in agricultural landscapes of southeastern Brazil. Brazilian government requires the maintenance of forests as legal reserve in each farm, and farmers need to maintain ponds as drinking water for cattle or crop irrigation. For this reason, the guidelines suggested in the present study can be easily adopted, without additional costs to rural productivity. PMID:24488040

  10. Multiple Determinants of Anuran Richness and Occurrence in an Agricultural Region in South-Eastern Brazil

    NASA Astrophysics Data System (ADS)

    Prado, Vitor H. M.; Rossa-Feres, Denise de C.

    2014-04-01

    In agricultural landscapes, studies that identify factors driving species richness and occupancy are important because they can guide farmers to use conservation practices that minimize species loss. In this context, anurans are threatened by habitat loss because they depend on the characteristics of both local water bodies and adjacent landscapes. We used a model selection approach to evaluate the influence of local and landscape variables in determining anuran species richness and occurrence in 40 freshwater bodies in a heavily deforested region of semideciduous Atlantic Forest in southeastern Brazil. Our aim was to develop recommendations for conservation of anuran communities in rural areas. Pond hydroperiod and area were the most important variables for explaining anuran species richness and occupancy, with greatest species richness being found in water bodies with intermediate hydroperiod and area. Other important variables that reflected individual species occupancies were the number of vegetation types and pond isolation. In addition, recent studies evidenced that water bodies near forest fragments have higher anuran abundance or diversity. In conclusion, we suggest the maintenance of semi-permanent ponds, isolated from large rivers or reservoirs and near forest fragments, as an effective strategy to conserve anuran fauna in agricultural landscapes of southeastern Brazil. Brazilian government requires the maintenance of forests as legal reserve in each farm, and farmers need to maintain ponds as drinking water for cattle or crop irrigation. For this reason, the guidelines suggested in the present study can be easily adopted, without additional costs to rural productivity.

  11. Sarcocystis lindsayi-like (Apicomplexa: Sarcocystinae) of the opossum (Didelphis aurita) from Southeastern Brazil.

    PubMed

    Stabenow, Cristiane S; De Oliveira, Francisco C R; Albuquerque, George R; Lopes, Carlos Wilson G

    2008-09-01

    Sporocysts of Sarcocystis were obtained from intestinal scrapings of three out of five opossums (Didelphis aurita) trapped in the southeastern region, of the State of Rio de Janeiro, Brazil. Fifteen caged budgerigars (Melopsittacus undulatus) received, orally, twenty-six sporocysts in 500 mL PBS, but only five belonging to one of the groups developed clinical signs, that consisted of anorexia, lethargy, ruffled feathers and dyspnoea, and parasitism in tissues. Two of the five budgerigars died on the 25th and 29th days after infection (DAI). The other three budgerigars were posted on the 30th DAI. In all the five infected birds were observed meronts in the capillaries of the lungs and cysts in muscles, mainly in the tongue and legs. PMID:20059875

  12. Two new species of Ulmeritoides Traver (Ephemeroptera: Leptophlebiidae) from Southeastern Brazil.

    PubMed

    Souto, Paula Malaquias; Da-Sil, Elidiomar Ribeirova; Nessimian, Jorge Luiz; Gonçalves, Inês Corrêa

    2016-01-01

    Two new species of Ulmeritoides Traver, 1959 are described from Southeastern Brazil based on male and female imagos. Ulmeritoides angelus sp. nov. (Holotype male deposited in DZRJ: Minas Gerais State) differs from all other species of the genus by the following combination of characters: forewings hyaline, base dark brown and purplish; veins R1 light brown; dark brown spots on bullae of veins Sc and R2; apex of penis lobes somewhat rounded, each with one central spine. Ulmeritoides tamoio sp. nov. (Holotype male deposited in DZRJ: São Paulo State) differs from all other species of the genus by the following combination of characters: wings hyaline; veins C, Sc and R1 brownish; brownish spots on bullae of veins Sc and R2; apex of penis lobes straight, ending in rather acute apical and mesal projections. An updated key to the genera Ulmeritoides Traver, 1956 and Ulmeritus Traver, 1956 is also given. PMID:27395967

  13. In situ measurements of contributions to the global electrical circuit by a thunderstorm in southeastern Brazil

    USGS Publications Warehouse

    Thomas, J.N.; Holzworth, R.H.; McCarthy, M.P.

    2009-01-01

    The global electrical circuit, which maintains a potential of about 280??kV between the earth and the ionosphere, is thought to be driven mainly by thunderstorms and lightning. However, very few in situ measurements of electrical current above thunderstorms have been successfully obtained. In this paper, we present dc to very low frequency electric fields and atmospheric conductivity measured in the stratosphere (30-35??km altitude) above an active thunderstorm in southeastern Brazil. From these measurements, we estimate the mean quasi-static conduction current during the storm period to be 2.5 ?? 1.25??A. Additionally, we examine the transient conduction currents following a large positive cloud-to-ground (+ CG) lightning flash and typical - CG flashes. We find that the majority of the total current is attributed to the quasi-static thundercloud charge, rather than lightning, which supports the classical Wilson model for the global electrical circuit.

  14. A new diminutive frog species of Adelophryne (Amphibia: Anura: Eleutherodactylidae) from the Atlantic Forest, southeastern Brazil.

    PubMed

    Lourenço-de-Moraes, Ricardo; Ferreira, Rodrigo Barbosa; Fouquet, Antoine; Bastos, Rogério Pereira

    2014-01-01

    The genus Adelophryne is composed of diminutive frogs occurring in northern Amazonia and the Atlantic Forest. Herein we describe a new species of Adelophryne found in the leaf litter of primary and secondary forests in the mountainous region of Espírito Santo state, southeastern Brazil. The new species is characterized by its small body size, two phalanges in the finger IV, and a glandular ridge line that runs from the posterior part of eye to the insertion of the forelimb. This species is sensitive to edge effect and conversion of native forest into coffee and Eucalyptus plantations and may be listed as Endangered (EN) under B1ab(iii) criteria of the IUCN Red List. PMID:25112256

  15. Genetic diversity of the Neotropical otter (Lontra longicaudis Olfers, 1818) in Southern and Southeastern Brazil.

    PubMed

    Trinca, C S; Waldemarin, H F; Eizirik, E

    2007-12-01

    The Neotropical otter is one of the least known otter species, and it is considered to be threatened to various degrees throughout its geographic range. Little information exists on the ecological characteristics of this species, and no genetic study has been published about it until now, hampering the design of adequate conservation strategies for its populations. To contribute with genetic information to comprehensive conservation efforts on behalf of L. longicaudis, we characterized the molecular diversity of the 5 portion of the mtDNA control region in samples from this species collected in Southern and Southeastern Brazil. The sequence analysis revealed a high level of haplotype diversity (h=0.819; SE=0.0052) and nucleotide variability ranging from 0.0039 to 0.0067. One of the sampled haplotypes was the most common in both regions and, from this sequence, several other (locally occurring) haplotypes could be derived by single point mutations. No significant genetic differentiation was observed between the Southern and Southeastern regions. PMID:18278347

  16. Sand fly fauna (Diptera: Psychodidae) from the Goytacazes National Forest and surrounding areas of southeastern Brazil.

    PubMed

    das Virgens, Thieres Marassati; Rezende, Helder Ricas; de Souza Pinto, Israel; Falqueto, Aloísio

    2015-06-01

    Most studies of the sand fly fauna in southeastern Brazil are conducted in the peridomiciliary environment of leishmaniasis endemic regions. Therefore, to increase the knowledge about diversity and richness of sand fly conservation areas, we describe here the sand fly fauna from the National Forest of Goytacazes (NFG), state of Espírito Santo, Brazil, and its surroundings areas. We also used sand fly fauna records from eight conservations units within the state of Espírito Santo to understand the similarity and relationships among them. The sand flies were simultaneously collected from June, 2008 to May, 2009 in two different environments: a preserved environment represented by the NFG and a modified environment represented by a peridomicile. To establish the similarity among the conservation units, we used a method very similar to parsimony analysis of endemism. We collected 2,466 sand fly specimens belonging to 13 species. Pressatia choti and Nyssomyia intermedia were the most abundant sand fly species. Ny. intermedia is a known vector of Leishmania braziliensis and epidemiological surveillance must be conducted in the area. We discuss aspects regarding the diversity of sand flies as well as the risk of transmission of Leishmania parasites in the area. We also provide for the first time a hypothesis of similarity relationships among conservation units within the state of Espírito Santo. PMID:26047181

  17. Ticks (Acari: Ixodidae) on swifts (Apodiformes: Apodidae) in Minas Gerais, southeastern Brazil.

    PubMed

    Tolesano-Pascoli, Graziela; Garcia, Frederico Innecco; Gomes, Carla Raphaela Gonzaga; Diniz, Kátia Cristina; Onofrio, Valeria Castilho; Venzal, José Manuel; Szabó, Matias Pablo Juan

    2014-10-01

    Brazil harbors five species of Cypseloidinae swifts. Those from Streptoprocne and Cypseloides genera have a very distinct ecology. They shelter at night and build nests in moist cliffs by waterfalls. Information about tick infestation of these birds is virtually non-existent and restricted to the description of a new species, Ixodes paranaensis, in Streptoprocne biscutata in Paraná State and another record of this species in Streptoprocne zonaris in Minas Gerais State. We herein report tick infestation of swifts at eight waterfalls in the Cerrado biome of Minas Gerais State, southeastern Brazil. Swifts were captured during six campaigns from November 2008 to April 2013. Overall, 584 swifts were captured (527 C. senex, four C. fumigatus and 53 S. zonaris). Four birds were tick infested (prevalence of 0.7 %). Three individuals of C. senex hosted one tick each; a nymph of I. paranaensis, a female of I. paranaensis and a nymph of Amblyomma cajennense. One S. zonaris hosted an I. paranaensis nymph and an Ornithodoros sp. larva (Argasidae). PMID:24696361

  18. Marine reservoir effect on the Southeastern coast of Brazil: results from the Tarioba shellmound paired samples.

    PubMed

    Macario, K D; Souza, R C C L; Aguilera, O A; Carvalho, C; Oliveira, F M; Alves, E Q; Chanca, I S; Silva, E P; Douka, K; Decco, J; Trindade, D C; Marques, A N; Anjos, R M; Pamplona, F C

    2015-05-01

    On the Southeastern coast of Brazil the presence of many archaeological shellmounds offers a great potential for studying the radiocarbon marine reservoir effect (MRE). However, very few such studies are available for this region. These archaeological settlements, mostly dating from 5 to 2 kyr cal BP, include both terrestrial and marine remains in good stratigraphic context and secure association, enabling the comparison of different carbon reservoirs. In a previous study the chronology of the Sambaqui da Tarioba, located in Rio de Janeiro state, Brazil, was established based on marine mollusc shells and charcoal samples from hearths, from several layers in two excavated sectors. We now compare the different materials with the aim of studying the MRE in this region. Calibration was performed with Oxford software OxCal v4.2.3 using the marine curve Marine13 with an undetermined offset to account for local corrections for shell samples, and the atmospheric curve SHCal13 for charcoal samples. The distribution of results considering a phase model indicates a ΔR value of -127 ± 67 (14)C yr in the 1 sigma range and the multi-paired approach leads to a mean value of -110 ± 94 (14)C yr. PMID:25703433

  19. Erosivity, surface runoff, and soil erosion estimation using GIS-coupled runoff-erosion model in the Mamuaba catchment, Brazil.

    PubMed

    Marques da Silva, Richarde; Guimarães Santos, Celso Augusto; Carneiro de Lima Silva, Valeriano; Pereira e Silva, Leonardo

    2013-11-01

    This study evaluates erosivity, surface runoff generation, and soil erosion rates for Mamuaba catchment, sub-catchment of Gramame River basin (Brazil) by using the ArcView Soil and Water Assessment Tool (AvSWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. Daily rainfall data between 1969 and 1989 from six rain gauges were used, and the monthly rainfall erosivity of each station was computed for all the studied years. In order to evaluate the calibration and validation of the model, monthly runoff data between January 1978 and April 1982 from one runoff gauge were used as well. The estimated soil loss rates were also realistic when compared to what can be observed in the field and to results from previous studies around of catchment. The long-term average soil loss was estimated at 9.4 t ha(-1) year(-1); most of the area of the catchment (60%) was predicted to suffer from a low- to moderate-erosion risk (<6 t ha(-1) year(-1)) and, in 20% of the catchment, the soil erosion was estimated to exceed > 12 t ha(-1) year(-1). Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the catchment was divided into four priority categories (low, moderate, high and very high) for conservation intervention. The study demonstrates that the AvSWAT model provides a useful tool for soil erosion assessment from catchments and facilitates the planning for a sustainable land management in northeastern Brazil. PMID:23652539

  20. Peridomiciliary Breeding Sites of Phlebotomine Sand Flies (Diptera: Psychodidae) in an Endemic Area of American Cutaneous Leishmaniasis in Southeastern Brazil

    PubMed Central

    Vieira, Vivaldo Pim; Ferreira, Adelson Luiz; Biral dos Santos, Claudiney; Leite, Gustavo Rocha; Ferreira, Gabriel Eduardo Melim; Falqueto, Aloísio

    2012-01-01

    The occurrence of American cutaneous leishmaniasis (ACL) in areas modified by humans indicates that phlebotomine sand fly vectors breed close to human habitations. Potential peridomiciliary breeding sites of phlebotomines were sampled in an area of transmission of Leishmania (Viannia) braziliensis in Southeastern Brazil. Three concentric circles rounding houses and domestic animal shelters, with radii of 20, 40, and 60 m, defined the area to be monitored using adult emergence traps. Of the 67 phlebotomines collected, Lutzomyia intermedia comprised 71.6%; Lutzomyia schreiberi, 20.9%; and Lutzomyia migonei, 4.5%. The predominance of L. intermedia, the main species suspected of transmitting L. (V.) braziliensis in Southeastern Brazil, indicates its participation in the domiciliary transmission of ACL, providing evidence that the domiciliary ACL transmission cycle might be maintained by phlebotomines that breed close to human habitations. This finding might also help in planning measures that would make the peridomiciliary environment less favorable for phlebotomine breeding sites. PMID:23091196

  1. A new species of Lonchophylla (Chiroptera, Phyllostomidae) from the Atlantic Forest of southeastern Brazil, with comments on L. bokermanni.

    PubMed

    Dias, Daniela; Esbérard, Carlos Eduardo L; Moratelli, Ricardo

    2013-01-01

    We examined Brazilian species of the nectar-feeding bats genus Lonchophylla (Phyllostomidae, Lonchophyllinae) to clarify the identity of Lonchophylla bokermanni and to determine the distribution of this and other species of Lonchophylla in eastern Brazil. As a result, we have found sufficient differences between Cerrado populations (including the type locality of L. bokermanni) and populations inhabiting the Atlantic Forest of southeastern Brazil,which warrant the treatment of the Atlantic Forest populations as a separate and new species. We describe this new species here as Lonchophylla peracchii, sp. nov. The new species appears to be restricted to the Atlantic Forest, whereas L. bokermanni is found only in Cerrado habitats. PMID:26171531

  2. New record of Pelecitus sp. (Nematoda, Onchocercidae) as a parasite of Athene cunicularia (Strigiformes, Strigidae) in southeastern Brazil.

    PubMed

    Silva, Tarcísio Macedo; Okamoto, Adriano Sakai; Silva, Lidiane Aparecida Firmino da; Smaniotto, Bruna Domeneghetti; Silva, Reinaldo José da; Andreatti Filho, Raphael Lucio

    2014-01-01

    The aim of this study was to report the burrowing owl Athene cunicularia as a new host for the filarid nematode Pelecitus sp. in southeastern Brazil for the first time, as well as reporting the occurrence of this nematode species in the body cavity, near the cervical air sac and lung region. This study contributes towards knowledge of parasitism in Brazilian wild birds and an anatomical region of the host as an infection site for Pelecitus sp. PMID:25054513

  3. Stream water quality in the context of payments for environmental services in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Piccolo, M. C.; Reis, L. D. C.; Figueiredo, R. D. O.; Camargo, P. B. D.; Costa, C. F. G. D.; Zuccari, M. L.; Green, T. R.

    2015-12-01

    Public policy of payment for environmental services (PES) was established in 2007 to face the challenge of recuperatingwater resources at one of the headwater areas of the Jaguari River Basin, which supplies an important reservoir for the metropolitan region of São Paulo, Brazil. Such effort consists of reforestation of riparian zones and spring lands at the hills of selected catchments, including the Ribeirão das Posses (RP) catchment. Since 2012 the University of São Paulo has developed research at RP to monitor the benefits of these practices on stream water quality, and identified a few parameters as good indicators to follow up the results of this PES program. The present study has the objective to show results of the monthly monitoring in2015,including 13 sampling stations at RP catchment distributed as follows: one in a spring forested area, three in spring areas of different ages of reforestation (3, 5 and 8 years), and nine at reaches of RP streamlocated in a way to contemplate the effects of the first order streams that comes from the studied spring areas entering RP. We established two additional stations at the Jaguari River, upstream and downstream of RP outlet. In situ measurements include temperature, pH, electric conductivity (EC) and dissolved oxygen (DO), and collect water samples to bring to the laboratory for analyses of dissolved organic and inorganic carbon (DOC and DIC), total nitrogen (TN) and alkalinity. Also, sediments (fine fraction: >0.45 μm; and coarse fraction: >63 μm) are collected for isotopic carbon analyses. Preliminary results show pH values ranging from 5.5 to 7.8, while DO ranges from 5.8 to 8.9 mg L-1. As for EC, the mean at the spring forested station was 34.6 μS cm-1, while at spring areas of 3, 6 and 8 years of reforestation they were 53.3, 73.8 and 34.8 μS cm-1, respectively. We expected that by the end of this annual monitoring the benefits of reforestation will be affirmed.

  4. Persistent organic pollutants in liver of Brazilian sharpnose shark (Rhizoprionodon lalandii) from southeastern coast of Brazil.

    PubMed

    Cascaes, M J; Oliveira, R T; Ubarana, M M; Sato, R M; Baldassin, P; Colabuono, F I; Leonel, J; Taniguchi, S; Weber, R R

    2014-09-15

    In the present study, persistent organic pollutants (POPs) were determined in 14 livers from specimens of the Brazilian sharpnose shark (Rhizoprionodon lalandii), which is an important economic resource for small-scale fisheries on the southeastern coast of Brazil. The following concentrations (lipid weight) of POPs were found: ∑PCBs: 1019±267 ng g(-1); ∑DDTs: 111±40 ng g(-1) and ∑PBDEs: 10.4±4.78. PCB 153 made the greatest contribution to ∑PCB (21.4%), followed by PCB 138 (14.6%) and PCB 180 (9.94%). Among chlorinated pesticides, only the p,p'-DDE and p,p'-DDD isomers had concentrations above the detection limit. Moreover, levels above the detection limit were found only for PBDE congeners 47 and 100 (BDEs 47>99). On average, BDE 47 accounted for 88% of the total PBDE load. The feeding habits of the Brazilian sharpnose shark close to the Brazilian coastline are likely the most important difference regarding the accumulation of POPs in comparison to oceanic species that feed in deeper waters. Thus, this species may be used to evaluate the pollution of coastal areas as well as human exposure to contaminants, as the Brazilian sharpnose shark is a frequently used for human consumption. Further studies in other areas of Brazil and involving other species are needed to clarify the mechanisms and potential impact of POPs, which can affect the biology of different organisms and cause population declines. PMID:25127497

  5. Feature-oriented regional modeling and simulations (FORMS) for the western South Atlantic: Southeastern Brazil region

    NASA Astrophysics Data System (ADS)

    Calado, L.; Gangopadhyay, A.; da Silveira, I. C. A.

    The multi-scale synoptic circulation system in the southeastern Brazil (SEBRA) region is presented using a feature-oriented approach. Prevalent synoptic circulation structures, or "features," are identified from previous observational studies. These features include the southward-flowing Brazil Current (BC), the eddies off Cabo São Tomé (CST - 22°S) and off Cabo Frio (CF - 23°S), and the upwelling region off CF and CST. Their synoptic water-mass ( T- S) structures are characterized and parameterized to develop temperature-salinity ( T- S) feature models. Following [Gangopadhyay, A., Robinson, A.R., Haley, P.J., Leslie, W.J., Lozano, C.J., Bisagni, J., Yu, Z., 2003. Feature-oriented regional modeling and simulation (forms) in the gulf of maine and georges bank. Cont. Shelf Res. 23 (3-4), 317-353] methodology, a synoptic initialization scheme for feature-oriented regional modeling and simulation (FORMS) of the circulation in this region is then developed. First, the temperature and salinity feature-model profiles are placed on a regional circulation template and objectively analyzed with available background climatology in the deep region. These initialization fields are then used for dynamical simulations via the Princeton Ocean Model (POM). A few first applications of this methodology are presented in this paper. These include the BC meandering, the BC-eddy interaction and the meander-eddy-upwelling system (MEUS) simulations. Preliminary validation results include realistic wave-growth and eddy formation and sustained upwelling. Our future plan includes the application of these feature models with satellite, in-situ data and advanced data-assimilation schemes for nowcasting and forecasting the SEBRA region.

  6. Ectoparasitic flies (Diptera, Streblidae) of bats (Chiroptera, Phyllostomidae) in an Atlantic Forest area, southeastern Brazil.

    PubMed

    França, D S; Pereira, S N; Maas, A C S; Martins, M A; Bolzan, D P; Lima, I P; Dias, D; Peracchi, A L

    2013-11-01

    We studied infestation rates and parasite-host associations between streblid flies and phyllostomid bats in an Atlantic Forest area of Rio de Janeiro state, southeastern Brazil. We captured 301 individuals from seven Phyllostomidae bat species. Out of that total, 69 bats had been parasitised by nine Streblidae species; the most frequent species were Trichobius joblingi and Trichobius tiptoni. The species Paraeuctenodes longipes, associated with Anoura geoffroyi, was the most frequent species. The highest mean intensity was observed for Paraeuctenodes longipes, associated with A. geoffroyi, and Paratrichobius longicrus associated with Artibeus lituratus, both ectoparasite species with a mean intensity of five individuals per bat. Trichobius joblingi exhibited the highest mean abundance, which was over three on its host species. Streblid richness in the study area was similar to the richness found in other studies carried out in the Atlantic Forest. We observed that streblid richness in this biome depends more on inherent characteristics of each physiognomy and on the host-species than on the sampling effort. PMID:24789402

  7. Holocene dynamics of vegetation change in southern and southeastern Brazil is consistent with climate forcing

    NASA Astrophysics Data System (ADS)

    Rodrigues, Jackson Martins; Behling, Hermann; Giesecke, Thomas

    2016-08-01

    At mid to high northern latitudes postglacial vegetation change has often occurred synchronously over large regions triggered mainly by abrupt climate change. Based on 19 pollen diagrams from southern and southeastern Brazil we explore if similar synchronicities in vegetation change were also characteristic for the vegetation dynamics in low latitudes. We used sequence splitting to detect past vegetation change in the pollen diagrams and computed principal curves and rates of change to visually evaluate the changes in composition and dynamics. The results show that vegetation change occurred mostly during the second half of the Holocene with distinct episodes of change. The character of vegetation change is generally consistent with shifts to wetter conditions and agrees with inferred shifts of the South American Monsoon. Speleothems as well as the titanium record from the Cariaco Basin indicate several episodes of rapid shifts in the precipitation regime, which are within the dating uncertainty of the here detected periods of vegetation change (8900, 5900, 2800, 1200 and 550 cal yrs BP). Our results indicate that low latitude vegetation composition follows precession forcing of the hydrology, while change is often triggered and synchronized by rapid climate change much like in high and mid latitudes. Pollen diagrams document changes in the abundance of individual taxa and changes in the amount of woodland cover, while small compositional changes indicate a regional stability of vegetation types during the Holocene.

  8. Whistles of small groups of Sotalia fluviatilis during foraging behavior in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Pivari, Daniela; Rosso, Sergio

    2005-10-01

    Whistle emissions were recorded from small groups of marine tucuxi dolphins (Sotalia fluviatilis) in two beaches located in an important biological reserve in the Cananéia estuary (25°03'S, 47°58'W), southeastern Brazil. A total of 17 h of acoustic data was collected when dolphins were engaged in a specific feeding foraging activity. The amount of 3235 whistles was recorded and 40% (n=1294) were analyzed. Seven acoustic whistle parameters were determined: duration (ms), number of inflection points, start and end frequency (kHz), minimum and maximum frequency (kHz), and frequency range (kHz). Whistles with up to four inflection points were found. Whistles with no inflection points and rising frequency corresponded to 85% (n=1104) of all analyzed whistles. Whistle duration varied from 38 to 627 ms (mean=229.6+/-109.9 ms), with the start frequency varying between 1 and 16 kHz (mean=8.16+/-3.0 kHz) and the end frequency between 2 and 18 kHz (mean=14.35+/-3.0 kHz). The importance of this study requires an accurate measurement of the whistles' emissions in an unusual foraging feeding behavior situation on two beaches where several tucuxis, mostly mother-calf pairs, are frequently present. These two beaches are located in a federal and state environment Environmental Protected Area threatened by the progressive increase of tourism.

  9. Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil.

    PubMed

    Favaro, E G P; Sipaúba-Tavares, L H; Milstein, A

    2015-11-01

    In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study. PMID:26602348

  10. Batflies parasitic on some phyllostomid bats in southeastern Brazil: parasitism rates and host-parasite relationships.

    PubMed

    Komeno, C A; Linhares, A X

    1999-01-01

    Ectoparasitic batflies were studied on 12 species of phyllostomid bats, by making 35 nightly collections of bats using mist nets at the "Panga" Ecological Reservation near Uberlândia, State of Minas Gerais, southeastern Brazil, from August 1989 to July 1990. Eleven species of Streblidae and one of Nycteribiidae were collected on 12 species of bats. Prevalence of ectoparasitic flies was lower than those reported by other authors for the New World and may be the result of the lack of caves in the study area, causing bats to roost in less favorable locations, forming smaller colonies. The fly, Trichobius joblingi Wenzel, was found on Carollia perspicillata (Linnaeus), showing preference for adult male bats. This could be explained by the predominance of males in the bat colonies, and by the fact that females rest in isolation during the reproductive period making them less exposed to the parasites. The streblid flies, Aspidoptera falcata Wenzel and Megistopoda proxima (Séguy), were found on Sturnira lilium (Geoffroy). A. falcata occurred mainly on young and adult females, whereas M. proxima did not show any preferences relative to the reproductive condition of the host. Ecological factors are important in determining differential numbers of parasites occurring on the different sexes, ages and reproductive state of the hosts. PMID:10224519

  11. Seasonal Variation and Frequency Distribution of Ectoparasites in Crossbreed Cattle in Southeastern Brazil

    PubMed Central

    Ferraz da Costa, Maria do Socorro; Guimarães, Marcos Pezzi; Lima, Walter dos Santos; Ferraz da Costa, Ana Julia; Facury Filho, Elias Jorge; Araujo, Ricardo Nascimento

    2014-01-01

    The aims of this study were to evaluate the seasonal variation and frequency distribution of Rhipicephalus (Boophilus) microplus, Haematobia irritans, and Dermatobia hominis on crossbred heifers under field conditions in the northeast of Minas Gerais state, southeastern Brazil. From November 2007 to September 2009 (23 months), 40 heifers aged 16.6 ± 2.4 months were divided into groups A (1/4 Holstein × 3/4 Gir) and B (1/2 Holstein × 1/2 Gir) and had the monthly infestation estimated along with the climatic conditions. The mean maximum and minimum temperatures were 28.5 and 19°C, respectively. The ectoparasites were present on animals in all months of the year. The levels of ticks on the animals were low (3.0 ± 0.2 ticks/animal), with the highest density in midwinter. The temperature was the climatic factor that most influenced the tick levels. The population of H. irritans (13.9 ± 0.3 flies/animal) and D. hominis (1.5 ± 0.2 larvae/animal) on heifers was more influenced by rainfall and exhibited two population peaks during the year. 1/2 Holstein heifers harbored significantly more H. irritans and D. hominis than 1/4 Holstein heifers. The results are discussed considering the most appropriate periods to apply ectoparasiticides and the genetic make-up of the animals. PMID:26464941

  12. [Ants as biological indicators of human impact in mangroves of the southeastern coast of Bahia, Brazil].

    PubMed

    Delabie, Jacques H C; Paim, Valéria R L de M; Do Nascimento, Ivan C; Campiolo, Sofia; Mariano, Cléa dos S F

    2006-01-01

    Mangroves are common in estuaries along the Atlantic coast of Brazil. Although plant diversity is low, this ecosystem supports a range of animals, offering some resources for non-aquatic organisms. Many insects live in mangroves and, between them, many ant species that are exclusively arboreous. Mangroves throughout the world suffer from high levels of human impact, and this is particularly true for southeastern Bahia, where land-uses include traditional crab and fish exploitation, urban development, refuse pollution, recreation, and timber extraction. The ants of 13 mangrove sites, representing a range of levels of human use, have been studied along 250 km of the southern Bahia littoral, between Itacaré and Porto Seguro. Ants were sampled both inside and on the periphery of the tidal zone, using entomological rainbow, baiting, collect of hollow branches and pit-fall. A total of 108 species have been collected, with the richest genera being Camponotus and Pseudomyrmex, and the most frequent belonging to the genera Azteca and Crematogaster. The ant community living on the periphery of mangrove areas is rather homogeneous regardless of the degree of environmental perturbation, but varies markedly with the disturbance inside the mangroves themselves. The evolution of richness of the both communities, mangrove and periphery, is negatively related to the human effects, even limited to the periphery. Ant communities therefore have the potential to be useful as biological indicators of ecological impacts of land-use in these mangrove systems. PMID:17144131

  13. Ultrastructure and pollen morphology of Bromeliaceae species from the Atlantic Rainforest in Southeastern Brazil.

    PubMed

    Silva, Vanessa J D; Ribeiro, Ester M; Luizi-Ponzo, Andrea P; Faria, Ana Paula G

    2016-01-01

    Pollen grain morphology of Bromeliaceae species collected in areas of the Atlantic Rainforest of southeastern Brazil was studied. The following species were analyzed: Aechmea bambusoides L.B.Sm. & Reitz, A. nudicaulis (L.) Griseb., A. ramosa Mart. ex Schult.f., Ananas bracteatus (Lindl.) Schult.f., Billbergia distachia (Vell.) Mez, B. euphemiae E. Morren, B. horrida Regel, B. zebrina (Herb.) Lindl., Portea petropolitana (Wawra) Mez, Pitcairnia flammea Lindl., Quesnelia indecora Mez, Tillandsia polystachia (L.) L., T. stricta Sol., T. gardneri Lindl., T. geminiflora Brongn. and Vriesea grandiflora Leme. Light and scanning electron microscopy were used and the species were grouped into three pollen types, organized according to aperture characteristics: Type I - pantoporate pollen grains observed in P. petropolitana, Type II - 2-porate pollen grains, observed in the genera Ananas, Aechmea and Quesnelia, and Type III - 1-colpate pollen grains, observed in the genera Billbergia, Pitcairnia, Tillandsia and Vriesea. Pollen data led to the construction of an identification key. The results showed that the species analyzed can be distinguished using mainly aperture features and exine ornamentation, and that these characteristics may assist in taxonomic studies of the family. PMID:27168370

  14. Whistles emitted by Atlantic spotted dolphins (Stenella frontalis) in Southeastern Brazil.

    PubMed

    Azevedo, Alexandre F; Flach, L; Bisi, Tatiana L; Andrade, Luciana G; Dorneles, Paulo R; Lailson-Brito, J

    2010-04-01

    The whistles of Atlantic spotted dolphins have been studied in a few localities of the North Atlantic Ocean and those studies revealed that the species emits whistles within a broad frequency range, with a high number of inflection points and presence of harmonics. In the South Atlantic Ocean, there is no information about the sounds produced by Atlantic spotted dolphins. A total of 1092 whistles emitted by free-ranging Atlantic spotted dolphins in Southeastern Brazilian coastal waters were analyzed. Whistles recorded in this study had a broad frequency range from 1.15 to 23.44 kHz. Whistles without harmonics were frequently emitted (N=701; 64.2%) and those signals with zero up to two inflection points corresponded to 94% of all whistles. Some differences in whistle characteristics (inflection points and duration) were found in relation to areas in North Atlantic Ocean and whistles were shorter and with a smaller number of inflection points in Brazil. Whistles produced by Atlantic spotted dolphins varied between the two behavioral states in which dolphins were engaged. Whistles were more frequently emitted when dolphins presented behaviors that included fast movement at surface, prey pursuit, aerial behavior, and physical contact. In these situations, whistles were on average longer and had higher frequency parameters than those emitted when animals were engaged in slowly and moderate traveling. The findings presented herewith reveal that dolphins modified whistle structures within behavioral states. PMID:20370045

  15. Access to prenatal care: inequalities in a region with high maternal mortality in southeastern Brazil.

    PubMed

    Martinelli, Katrini Guidolini; Santos Neto, Edson Theodoro Dos; Gama, Silvana Granado Nogueira da; Oliveira, Adauto Emmerich

    2016-05-01

    Aim This article aims to evaluate access to prenatal care according to the dimensions of availability, affordability and acceptability in the SUS microregion of southeastern Brazil. Methods A cross-sectional study conducted in 2012-2013 that selected 742 postpartum women in seven hospitals in the region chosen for the research. The information was collected, processed and submitted to the chi-square test and the nonparametric Spearman's test, with p-values less than 5% (p < 0.05). Results Although the SUS constitutionally guarantees universal access to health care, there are still inequalities between pregnant women from rural and urban areas in terms of the availability of health care and among families earning up to minimum wage and more than one minimum wage per month in terms of affordability; however, the acceptability of health care was equal, regardless of the modality of the health services. Conclusion The location, transport resources and financing of health services should be reorganised, and the training of health professionals should be enhanced to provide more equitable health care access to pregnant women. PMID:27166912

  16. A checklist of arthropods associated with pig carrion and human corpses in southeastern brazil.

    PubMed

    Carvalho, L M; Thyssen, P J; Linhares, A X; Palhares, F A

    2000-01-01

    Necrophagous insects, mainly Diptera and Coleoptera, are attracted to specific stages of carcass decomposition, in a process of faunistic succession. They are very important in estimating the postmortem interval, the time interval between the death and the discovery of the body. In studies done with pig carcasses exposed to natural conditions in an urban forest (Santa Genebra Reservation), located in Campinas, State of São Paulo, southeastern Brazil, 4 out of 36 families of insects collected - Calliphoridae, Sarcophagidae, Muscidae (Diptera) and Dermestidae (Coleoptera) - were considered of forensic importance, because several species were collected in large numbers both visiting and breeding in pig carcasses. Several species were also observed and collected on human corpses at the Institute of Legal Medicine. The species belonged to 17 different families, 6 being of forensic importance because they were reared from human corpses or pig carcasses: Calliphoridae, Sarcophagidae, Muscidae, Piophilidae (Diptera), Dermestidae, Silphidae and Cleridae (Coleoptera). The most important species were: Diptera - Chrysomya albiceps, Chrysomya putoria, Hemilucilia segmentaria, Hemilucilia semidiaphana (Calliphoridae), Pattonella intermutans (Sarcophagidae), Ophyra chalcogaster (Muscidae), Piophila casei (Piophilidae); Coleoptera - Dermestes maculatus (Dermestidae), Oxyletrum disciolle (Silphidae) and Necrobia rufipes (Cleridae). PMID:10656720

  17. Identification and characterization of Wolbachia in Solenopsis saevissima fire ants (Hymenoptera: Formicidae) in southeastern Brazil.

    PubMed

    Fernando de Souza, Rodrigo; Daivison Silva Ramalho, João; Santina de Castro Morini, Maria; Wolff, José Luiz Caldas; Araújo, Ronaldo Carvalho; Mascara, Douglas

    2009-03-01

    The genus Solenopsis appears to have evolved and radiated very rapidly in South America and then spread throughout the rest of the continent. As part of the expansion process, distribution patterns and different degrees of geographic isolation among populations of S. saevissima can be observed. We have investigated the presence of Wolbachia in 52 colonies and 1623 individuals in southeastern Brazil. Detection of Wolbachia infection was based on amplification of the 16S rRNA and wsp genes by polymerase chain reactions. Wolbachia was found in only one of the four locations investigated and it was observed that the populations were polymorphic for infection. The infection level observed increased during the period of screening. In particular, double infection (16SWA and B) increased from 44% in 2005 to 90% in 2006. The A-group of Wolbachia from the wsp sequences was determined by sequencing. However, two variant wsp sequences were detected in Wolbachia present in these populations. The alignment of our sequences with those deposited in GenBank indicated significant differences in relation to homologous sequences. Phylogenetic relationships were inferred using parsimony, and confidence intervals were estimated by bootstrapping. Then the divergence of the Wolbachia of S. saevissima in the populations studied with other variants allowed us to verify that wSS1 and dwSS2 formed a distinct clade within the A-group (>75%). These results can be useful in studies on the dynamics of ant populations. PMID:18979132

  18. Hydrological modelling in small, semi-arid catchments of south-eastern Australia: reforestation affects groundwater but not streamflow

    NASA Astrophysics Data System (ADS)

    Dean, Joshua; Camporese, Matteo; Grover, Samantha; Webb, John; Dresel, Evan; Daly, Edoardo

    2015-04-01

    Land use has a strong influence on evapotranspiration (ET) and thus a large effect on catchment hydrology. The dearth of data from arid and semi-arid catchments limits the understanding of the possible effects of land-use and land-use change on water resources in these environments. Here we use three years of rainfall, streamflow, and groundwater level measurements to estimate the water balance components in two small, adjacent ephemeral Australian catchments, one predominantly covered with a young eucalypt plantation and the other primarily dedicated to grazing pasture. The average annual rainfall for the study area is ~670 mm, with ET greatly exceeding rainfall for most of the year, excepting the winter months of May through September. The paired catchments are similar in size and are situated on the same Devonian granitic geology. Land-use is the most striking difference between the catchments; this allows for a strong hydrological comparison of the eucalypt catchment (planted in 2008) with the pasture catchment. The majority of data is available from 2009 until present, although historical bi-monthly groundwater level data exists back to 1986. We focus on 2010-2012, and we have maximum data for 2012, including eddy covariance and sap flow measurements. The integrated hydrological model CATHY was calibrated and validated against the data in the two catchments for 2011 and 2012. The water balances estimated from both data and model show a significant increase in ET in the eucalypt plantation catchment at the expense of groundwater storage: ET accounted for 95-97% of rainfall in the pasture catchment and 104-110% in the eucalypt catchment across the three years studied. Direct measurements of ET in 2012 confirm the water balance values. However, streamflow was more or less constant at 3-4% of rainfall in both catchments for the study period. The model results suggest that this is because streamflow is generated primarily from surface runoff, showing that land use

  19. Cytogenetic and Molecular Data Demonstrate that the Bryconinae (Ostariophysi, Bryconidae) Species from Southeastern Brazil Form a Phylogenetic and Phylogeographic Unit

    PubMed Central

    Travenzoli, Natália Martins; Silva, Priscilla Caroline; Santos, Udson; Zanuncio, José Cola; Oliveira, Claudio; Dergam, Jorge Abdala

    2015-01-01

    Brycon spp. occur in Neotropical watersheds to the west and east of the Andes, and as they are sensitive to anthropogenic changes, many these species are endangered in southeastern Brazil. Coastal rivers in southeastern Brazil are characterized by the presence of relatively few freshwater fish species and high endemism of this fauna. The objective of this study was to examine whether Brycon spp. occurring in the coastal basins of southeastern Brazil are monophyletic, using cytogenetic data, mitochondrial, and nuclear molecular markers. All the species showed a diploid number of 50 chromosomes, a conserved number within the subfamily Bryconinae. However, the karyotypic formulas were unique to most species, including Brycon devillei (26m+22sm+2st), Brycon ferox (26m+12sm+12st), Brycon insignis (22m+20sm+8st), Brycon opalinus, and Brycon vermelha (24m+20sm+6st), indicating the prevalence of pericentric and paracentric inversions in the chromosomal evolution of these species. All of them had nucleolar organizer regions in the first pair of subtelocentric chromosomes and no equilocal distribution of heterochromatin in the first pair of chromosomes of the karyotype. These two features, not seen in any other Brycon spp. examined to date, indicate that Bryconinae species from the Brazilian southeastern coastal basins, including the monotypic genus Henochilus, are monophyletic. Also, this is the first study that reports NOR location and C-banding patterns as synapomorphies for a Neotropical fish species group. The monophyly was also supported by a phylogenetic analysis of 16S rDNA (16S), cytochrome oxidase subunit I (COI), alpha-myosin (MYH6) genes and S72 intron molecular data. Our results partially corroborate the “Brycon acuminatus” group proposed by Howes in 1982: our proposed clade keeps B. devillei, B. ferox, and B. insignis; but it also includes B. opalinus, B. vermelha, and H. weatlandii whereas it excludes B. nattereri. The phylogeographic unit formed by

  20. Molecular evidence of two cryptic species of Stramonita (Mollusca, Muricidae) in the southeastern Atlantic coast of Brazil

    PubMed Central

    De Biasi, Juliana Beltramin; Tomás, Acácio Ribeiro Gomes; Hilsdorf, Alexandre Wagner Silva

    2016-01-01

    Abstract Snails of the genus Stramonita are commonly found in the rocky intertidal habitat of the western Atlantic Ocean coast. They belong to a monophyletic taxon that occurs along the tropical and warm-temperate Atlantic and eastern Pacific rocky shores. This genus comprises different valid species and members of the S. haemastoma complex. In the present study, samples of Stramonita were collected from three different regions of southeastern Brazil. Partial sequences of two mitochondrial genes, COI and 16S rRNA, were used to compare nucleotides sequences between Stramonita specimens. Levels of nucleotide divergence greater than 2% across the three sampled regions were used for differentiation at the species level. One of the identified species was S. brasiliensis, which has recently been described by molecular analysis; the other species may represent S. haemastoma, not yet described in the southeastern Brazilian coast. PMID:27560649

  1. Molecular evidence of two cryptic species of Stramonita (Mollusca, Muricidae) in the southeastern Atlantic coast of Brazil.

    PubMed

    De Biasi, Juliana Beltramin; Tomás, Acácio Ribeiro Gomes; Hilsdorf, Alexandre Wagner Silva

    2016-01-01

    Snails of the genus Stramonita are commonly found in the rocky intertidal habitat of the western Atlantic Ocean coast. They belong to a monophyletic taxon that occurs along the tropical and warm-temperate Atlantic and eastern Pacific rocky shores. This genus comprises different valid species and members of the S. haemastoma complex. In the present study, samples of Stramonita were collected from three different regions of southeastern Brazil. Partial sequences of two mitochondrial genes, COI and 16S rRNA, were used to compare nucleotides sequences between Stramonita specimens. Levels of nucleotide divergence greater than 2% across the three sampled regions were used for differentiation at the species level. One of the identified species was S. brasiliensis, which has recently been described by molecular analysis; the other species may represent S. haemastoma, not yet described in the southeastern Brazilian coast. PMID:27560649

  2. Molecular evidence of two cryptic species of Stramonita (Mollusca, Muricidae) in the southeastern Atlantic coast of Brazil.

    PubMed

    De Biasi, Juliana Beltramin; Tomás, Acácio Ribeiro Gomes; Hilsdorf, Alexandre Wagner Silva

    2016-07-01

    Snails of the genus Stramonita are commonly found in the rocky intertidal habitat of the western Atlantic Ocean coast. They belong to a monophyletic taxon that occurs along the tropical and warm-temperate Atlantic and eastern Pacific rocky shores. This genus comprises different valid species and members of the S. haemastoma complex. In the present study, samples of Stramonita were collected from three different regions of southeastern Brazil. Partial sequences of two mitochondrial genes, COI and 16S rRNA, were used to compare nucleotides sequences between Stramonita specimens. Levels of nucleotide divergence greater than 2% across the three sampled regions were used for differentiation at the species level. One of the identified species was S. brasiliensis, which has recently been described by molecular analysis; the other species may represent S. haemastoma, not yet described in the southeastern Brazilian coast. PMID:27392237

  3. The Effects of Different Tillage Systems on Soil Hydrology and Erosion in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Bertolino, A. V. F. A.; Fernandes, N. F.; Souza, A. P.; Miranda, J. P.; Rocha, M. L.

    2009-04-01

    Conventional tillage usually imposes a variety of modifications on soil properties that can lead to important changes in the type and magnitude of the hydrological processes that take place at the upper portion of the soil profile. Plough pan formation, for example, is considered to be an important consequence of conventional tillage practices in southeastern Brazil, decreasing infiltration rates and contributing to soil erosion, especially in steep slopes. In order to characterize the changes in soil properties and soil hydrology due to the plough pan formation we carried out detailed investigations in two experimental plots in Paty do Alferes region, located in the hilly landscape of Serra do Mar in southeastern Brazil, close to Rio de Janeiro city. Farming activities are very important in this area, in particular the ones related to the tomato production. The local hilly topography with short and steep hillslopes, as well as an average annual rainfall of almost 2000 mm, favor surface runoff and the evolution of rill and gully erosion. The two runoff plots are 22m long by 4m wide and were installed side by side along a representative hillslope, both in terms of soil (Oxisol) and steepness. At the lower portion of each plot there is a collecting trough connected by a PVC pipe to a 500 and 1000 liters sediment storage boxes. Soil tillage treatments used in the two plots were: Conventional Tillage (CT), with one plowing using disc-type plow (about 18 cm depth) and one downhill tractor leveling, in addition to burning residues from previous planting; and Minimum Tillage (MT), which did not allow burning residues from previous planting and preserved a vegetative cover between plantation lines. Runoff and soil erosion measurements were carried out in both plots immediately after each rainfall event. In order to characterize soil water movements under the two tillage systems (CT and MT), 06 nests of tensiometers and 04 nests of Watermark sensors were installed in each

  4. Fallow Effects on Improving Soil Properties and Decreasing Erosion: Atlantic Forest, Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Miranda, J. P.; Silva, L. M.; Lima, R. L.; Donagemma, G. K.; Bertolino, A. V. A.; Fernandes, N. F.; Correa, F. M.; Polidoro, J. C.; Tato, G.

    2009-04-01

    Soil tillage plays a major role in changing physical and hydrological properties of soils through time, and in consequence, in the dynamics of infiltration, soil water and erosion. In the hilly landscape of southeastern Brazil, many areas originally occupied by the Atlantic Forest (one the most threatened biomes on the planet) have been continuously transformed in the last decades into agricultural systems, usually associated with small farming properties. Traditionally, the agricultural activities in these areas incorporate rotational systems which include a fallow period, where previously farmed areas repose for at least five years. In some areas, vegetation grows so fast that after 7 or 8 years these sites may be considered by regulator agencies as forests, impeding their use again for farming. As a consequence, farmers tend to decrease the amount of time used fallow impeding the recovery of original soil properties, reducing in consequence the infiltration rate, and increasing the runoff and erosion. Currently, the Brazilian laws allow that the farmers use the fallow system for 10 years in areas where this technique has been used traditionally. So, a major issue here is for how long the farming plots should be left reposing. Therefore, this study aims both to characterize the effects of continuous farming on soil physical and hydrological properties, as well as to define the impacts of different fallow periods on the improvement of soil properties and in the reduction of runoff and erosion. The experiments were carried out in a cultivation site located at Bom Jardim city, close to Rio de Janeiro city. The area is situated at about 800m of elevation in the hilly steep topography of the Serra do Mar, a coast range in southeastern Brazil, with an average total annual rainfall of 2000 mm. In this study, carried out in a typical farm of the area, we compared the effects of 5 different soil usages on soil properties: banana, coffee, F2 (2-year fallow), F5 (5-year

  5. Geomorphology Drives Amphibian Beta Diversity in Atlantic Forest Lowlands of Southeastern Brazil

    PubMed Central

    Luiz, Amom Mendes; Leão-Pires, Thiago Augusto; Sawaya, Ricardo J.

    2016-01-01

    Beta diversity patterns are the outcome of multiple processes operating at different scales. Amphibian assemblages seem to be affected by contemporary climate and dispersal-based processes. However, historical processes involved in present patterns of beta diversity remain poorly understood. We assess and disentangle geomorphological, climatic and spatial drivers of amphibian beta diversity in coastal lowlands of the Atlantic Forest, southeastern Brazil. We tested the hypothesis that geomorphological factors are more important in structuring anuran beta diversity than climatic and spatial factors. We obtained species composition via field survey (N = 766 individuals), museum specimens (N = 9,730) and literature records (N = 4,763). Sampling area was divided in four spatially explicit geomorphological units, representing historical predictors. Climatic descriptors were represented by the first two axis of a Principal Component Analysis. Spatial predictors in different spatial scales were described by Moran Eigenvector Maps. Redundancy Analysis was implemented to partition the explained variation of species composition by geomorphological, climatic and spatial predictors. Moreover, spatial autocorrelation analyses were used to test neutral theory predictions. Beta diversity was spatially structured in broader scales. Shared fraction between climatic and geomorphological variables was an important predictor of species composition (13%), as well as broad scale spatial predictors (13%). However, geomorphological variables alone were the most important predictor of beta diversity (42%). Historical factors related to geomorphology must have played a crucial role in structuring amphibian beta diversity. The complex relationships between geomorphological history and climatic gradients generated by the Serra do Mar Precambrian basements were also important. We highlight the importance of combining spatially explicit historical and contemporary predictors for understanding

  6. Production of Excirolana armata (Dana, 1853) (Isopoda, Cirolanidae) on an exposed sandy beach in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Petracco, Marcelo; Cardoso, Ricardo Silva; Turra, Alexander; Corbisier, Thais Navajas

    2012-09-01

    The somatic and gonad productions of the cirolanid isopod Excirolana armata were analyzed by taking monthly samples from December 2003 to November 2005 on Una beach, São Paulo state (24°S), southeastern Brazil. Sampling was performed along three fixed transects established from the base of the foredunes to the waterline. Weight-specific growth rate was used to estimate the E. armata somatic production for 2004 and 2005, separately. The gonad production was estimated based on the monthly reproductive potential (mean number of eggs/embryos per female × monthly abundance of ovigerous females with near-release broods) for 2004. The annual somatic production of E. armata population varied from 15.57 to 17.25 g AFDW m-1 year-1 and the somatic production/biomass ratio ( P s/ B) from 3.55 to 3.14 year-1 for 2004 and 2005, respectively. The P s/ B ratios were higher for males (4.02 and 3.19 year-1 for 2004 and 2005) than for females (3.10 year-1 for both years). The annual gonad production ( P g = 1.07 g AFDW m-1 year-1) contributed about 15 and 6% to the total production ( P s + P g) of females and the population, respectively. The proportion of gonad to somatic production of females ( P g/ P s) increased with individual size (ca 90% in the 7.5 mm size class), and the annual weight-specific gonad production ( P g/ B ratio) was estimated to 0.24 year-1. The high P s/ B ratios estimated for E. armata derive from the fast growth of individuals and show the importance of this population to the energy flow on Una beach ecosystem. However, the low percentage of juveniles verified in this population and in other studies of populations of the genus Excirolana is discussed as an important source of underestimation of P s/ B ratio.

  7. Prevalence and factors associated with scleral hyaline plaque: clinical study of older adults in southeastern Brazil

    PubMed Central

    Horowitz, Soraya; Damasceno, Nadyr; Damasceno, Eduardo

    2015-01-01

    Purpose To investigate the prevalence of scleral hyaline plaque among older adults in the city of Niterói in southeastern Brazil. A second goal was to assess the correlation between scleral hyaline plaque and several age-related diseases, including eye diseases and systemic diseases. Methods The study sample comprised 667 participants who were followed for 15 months. The study had a prospective, longitudinal, observational design that established inclusion and exclusion criteria. The following variables were selected for correlation with scleral hyaline plaque: sex, age, age range, iris color, ethnicity, presence of cataract, moderate to high myopia, age-related macular degeneration (AMD), diabetes mellitus, systemic arterial hypertension, degenerative arthritis, and osteoporosis. These correlations were assessed by means of the χ2 test and Student’s t-test. Multivariate analysis was performed to exclude factors that were potentially associated with aging exclusively but that did not have a direct relationship with hyaline plaque. Binary logistic regression was used to calculate odds ratios, significance, and confidence intervals. Results Scleral hyaline plaques were found in 177 patients (17.54%). There was a statistically significant association between the presence of hyaline plaques and sex (female), age range (≥70 years old), ethnicity (Caucasian), cataract, moderate to high myopia, systemic arterial hypertension, degenerative arthritis, and osteoporosis (P<0.05). On multivariate binary logistic regression analysis, only female sex, age range (≥70 years), moderate to high myopia, and degenerative arthritis exhibited significant correlation. Conclusion The prevalence of scleral hyaline plaque in the present study was higher than in previous reports in the medical literature. Several age-related diseases exhibited a correlation with scleral hyaline plaque. The most significant factors associated with scleral hyaline plaque were advanced age, female sex

  8. Reduction of social inequalities in life expectancy in a city of Southeastern Brazil

    PubMed Central

    2011-01-01

    Background Around the world the life expectancy at birth has risen steadily over time. However, this increase in life years is not equally distributed among different social segments of the population. Studies have demonstrated that social groups living in deprived areas have a shorter life expectancy at birth in comparison to affluent ones. The aim of this study was to evaluate inequalities in life expectancy by socioeconomic strata in a city with one million inhabitants in Southeastern Brazil, in 2000 and 2005. Methods Through an ecological approach, the 49 areas of health care units of the city were classified into three socioeconomic strata, defined according to variables of income and educational level of the heads of household obtained from the 2000 Census. Life tables were constructed by sex for each of the three socioeconomic strata in 2000 and 2005. Results The life expectancy at birth for men and women living in poor areas was 6.9 and 5.5 years lower in comparison to the affluent ones in 2000. Between 2000 and 2005, these social inequalities in life expectancy at birth reduced, since the groups with lower socioeconomic level had gained more life years. The increase in life expectancy at birth experienced by areas with worse living conditions was 3 times higher than the increment estimated for prosperous areas for both sexes. Males had the greatest gain in life years, leading to a narrowing of gender differentials in life expectancy between 2000 and 2005. Conclusions The reduction of social inequalities in life expectancy suggests that living and health conditions have improved over time, due to social and health policies. The expansion of both health care coverage and cash transfer policies could have had positive effects on mortality reduction and on the consequent increase in the life expectancy, especially for the poor population. PMID:21871100

  9. Metal, metallothionein and glutathione levels in blue crab (Callinectes sp.) specimens from southeastern Brazil.

    PubMed

    Lavradas, Raquel Teixeira; Hauser-Davis, Rachel Ann; Lavandier, Ricardo Cavalcanti; Rocha, Rafael Christian Chávez; Saint' Pierre, Tatiana D; Seixas, Tércia; Kehrig, Helena Amaral; Moreira, Isabel

    2014-09-01

    Metal concentrations (Cu, Pb, Zn and Cd) were determined in muscle, gills, soft tissues and eggs in male, non-ovigerous and ovigerous female Callinectes sp. specimens from a reference site in Southeastern Brazil. Metallothionein (MT) and reduced glutathione (GSH) levels were also determined. Results demonstrate that sex has a significant influence on metal, MT and GSH concentrations. Significant maternal transfer of Pb and Zn from ovigerous females to eggs was verified, while female crabs, both ovigerous and non-ovigerous, showed elevated GSH and MT in viscera when compared to males, indicating possible MT role in excreting metals to eggs in ovigerous females of this species. Several strong statistical correlations between metals and MT indicate MTs role in detoxification of both toxic and essential elements in different organs. Pb and Zn were significantly correlated to GSH, indicating oxidative stress caused by the former and a direct link between Zn and GSH in maintaining homeostasis. Regarding human consumption, metal concentrations were lower than the maximum permissible levels established by international and Brazilian regulatory agencies, indicating that this species is safe for human consumption concerning this parameter. The presence of metals in Callinectes sp., however, is still of importance considering that this is a key species within the studied ecosystem and, therefore, plays a major role in the transference of pollutants to higher trophic levels. In addition, the presence of significant metal concentrations found in eggs must be considered in this context, since crab eggs are eaten by several other species, such as shorebirds, seabirds, and fish. Also, to the best of our knowledge, this is the first study regarding both MT and GSH levels in Callinectes sp. eggs and is of interest in the investigation of molecular mechanisms regarding metal exposure in these crustaceans. Data reported in this study support the conclusions from previous reports

  10. Edge effect on post-dispersal artificial seed predation in the southeastern Amazonia, Brazil.

    PubMed

    Penido, G; Ribeiro, V; Fortunato, D S

    2015-05-01

    This paper evaluates the post-dispersal artificial seed predation rates in two areas of the southeastern Amazon forest-savanna boundary, central Brazil. We conducted the survey in a disturbance regime controlled research site to verify if exists an edge effect in these rates and if the disturbance (in this case annual fire and no fire) affects seed predation. We placed 800 peanuts seeds in each area at regular distance intervals from the fragment`s edge. Data were analyzed by a likelihood ratio model selection in generalized linear models (GLM). The complete model (with effects from edge distance and site and its interaction) was significative (F3=4.43; p=0.005). Seeds had a larger predation rates in fragment's interior in both areas, but in the controlled area (no disturbance) this effect was less linear. This suggests an edge effect for post-dispersal seed predation, and that disturbances might alter these effects. Even if we exclude the site effect (grouping both areas together) there is still a strong edge effect on seed predation rates (F3=32.679; p>0.001). We did not verify predator's species in this study; however, the presence of several species of ants was extremely common in the seeds. The detection of an edge effect in only a short survey time suggests that there is heterogeneity in predation rates and that this variation might affect plant recruitment in fragmented areas of the Amazon forest. Henceforth, this seed predation should be taken in consideration in reforestation projects, where the main source of plants species is from seed distribution. PMID:26132017

  11. Geomorphology Drives Amphibian Beta Diversity in Atlantic Forest Lowlands of Southeastern Brazil.

    PubMed

    Luiz, Amom Mendes; Leão-Pires, Thiago Augusto; Sawaya, Ricardo J

    2016-01-01

    Beta diversity patterns are the outcome of multiple processes operating at different scales. Amphibian assemblages seem to be affected by contemporary climate and dispersal-based processes. However, historical processes involved in present patterns of beta diversity remain poorly understood. We assess and disentangle geomorphological, climatic and spatial drivers of amphibian beta diversity in coastal lowlands of the Atlantic Forest, southeastern Brazil. We tested the hypothesis that geomorphological factors are more important in structuring anuran beta diversity than climatic and spatial factors. We obtained species composition via field survey (N = 766 individuals), museum specimens (N = 9,730) and literature records (N = 4,763). Sampling area was divided in four spatially explicit geomorphological units, representing historical predictors. Climatic descriptors were represented by the first two axis of a Principal Component Analysis. Spatial predictors in different spatial scales were described by Moran Eigenvector Maps. Redundancy Analysis was implemented to partition the explained variation of species composition by geomorphological, climatic and spatial predictors. Moreover, spatial autocorrelation analyses were used to test neutral theory predictions. Beta diversity was spatially structured in broader scales. Shared fraction between climatic and geomorphological variables was an important predictor of species composition (13%), as well as broad scale spatial predictors (13%). However, geomorphological variables alone were the most important predictor of beta diversity (42%). Historical factors related to geomorphology must have played a crucial role in structuring amphibian beta diversity. The complex relationships between geomorphological history and climatic gradients generated by the Serra do Mar Precambrian basements were also important. We highlight the importance of combining spatially explicit historical and contemporary predictors for understanding

  12. Aspects of the reproductive biology of the shortfin Mako, Isurus oxyrinchus (Elasmobranchii Lamnidae), in the southeastern region of Brazil.

    PubMed

    Costa, F E S; Braga, F M S; Arfelli, C A; Amorim, A F

    2002-05-01

    Uteri from four pregnant females and two newborn of shortfin mako, Isurus oxyrinchus, were collected in the southeastern region of Brazil, during September, October, and November of 1993 and 1994. All embryos were near-term with developing dentition and inner organs. Total length ranged from 64.5 to 72.0 cm, and the maximum number of embryos observed in a litter was 20. These observations further confirmed oophagy as a form of nutrition in this species, and its periodicity. The presence of teeth in the embryos' stomachs suggest that tooth replacement begins in the uterine phase. PMID:12489396

  13. Diet and helminths of Enyalius brasiliensis (Lacertilia, Iguania, Leiosauridae) in an Atlantic Rainforest remnant in southeastern Brazil.

    PubMed

    Dorigo, T A; Maia-Carneiro, T; Almeida-Gomes, M; Siqueira, C C; Vrcibradic, D; Van Sluys, M; Rocha, C F D

    2014-02-01

    Our study aimed to add information about the diet and endoparasites of Enyalius brasiliensis from an Atlantic Rainforest remnant in the state of Rio de Janeiro, southeastern Brazil. Regarding diet, E. brasiliensis consumed arthropods, with caterpillars and beetles being the most important preys. Regarding helminth parasites, overall prevalence was low (9.5%), with 238 nematodes of the genus Physaloptera found in the stomach of one specimen and one nematode of the genus Rhabdias inside the lung of another. Our results corroborate the observations of previous studies that indicate that lizards of the genus Enyalius tend to feed mainly on relatively large-bodied arthropods and to harbour depauperate endoparasite fauna. PMID:25055102

  14. Rift-zone magmatism: Petrology of basaltic rocks transitional from CFB to MORB, southeastern Brazil margin

    NASA Astrophysics Data System (ADS)

    Fodor, R. V.; Vetter, S. K.

    1984-12-01

    Compositions of basaltic samples from the southeastern Brazil passive margin (18° 24° S) depict the change from continental to oceanic lithosphere during the opening of the South Atlantic Ocean. Samples studied range from 138 to 105 m.y. old and are from 12 Petrobrás drill cores recovered from the coastline to about 150 km offshore in the Espirito Santo, Campos, and Santos basins. Compositions vary, ranging, for example, from 49 54 wt.% SiO2, 0.5 3.0 wt.% TiO2, 0.6 5.0 FeO*/MgO, and <1->6 La/ Yb(n), but can be grouped: (i) basalts enriched in incompatible elements, such as K (some K2O>2.0 wt.%), Rb (>18 ppm), Zr (>120 ppm), and LREE (some FeO* 16 wt.%; most with SiO2 51 54 wt.%), and resembling Serra Geral continental flood basalts (SG-CFB) of southern Brazil; (ii) basalts less enriched, or transitional, in incompatible elements, having K2O <0.40 wt.% and flat REE patterns, and resemble N. Atlantic diabases and FAMOUS basalts; and (iii) one depleted sample, Ce/Yb(n)=0.7, where Ce(n)=4. Expressed in oceanic-basalt terminology and Zr-Nb-Y abundances, ‘enriched’ samples are P- and T-type MORB (e.g., Zr/Nb ˜4 25), ‘transitional’ samples are T-type (Zr/ Nb ˜8 27), and the ‘depleted’ sample is N-type MORB (Zr/Nb>30). Trace-element ratios (e.g., Zr/Nb, Zr/Y) link the Brazil margin basalts to a heterogeneous mantle (attributed to metasomatic veining) of variably proportioned mixtures of depleted-mantle (N-MORB) and plume (P-MORB, e.g., Tristan hotspot) materials. The various compositions therefore reflect, in part, different zones of melting during the separation of Gondwanaland, where gradual decompression during rifting enabled concurrent melting of upper, more depleted (non- or sparsely-veined) mantle and enriched (densely-veined) mantle. Within the time represented, melting produced enriched, transitional, and depleted magmas that were emplaced subaerially, hypabyssally, and subaqueously; they mark the transition from CFB before rifting and separation

  15. Characteristics of whistles from rough-toothed dolphins (Steno bredanensis) in Rio de Janeiro coast, southeastern Brazil.

    PubMed

    Seabra de Lima, Isabela Maria; de Andrade, Luciana Guimarães; Ramos de Carvalho, Rafael; Lailson-Brito, José; de Freitas Azevedo, Alexandre

    2012-05-01

    There is no information about the whistles of rough-toothed dolphins in the South Atlantic Ocean. This study characterizes the whistle structure of free-ranging rough-toothed dolphins recorded on the Rio de Janeiro coast, southeastern Brazil, and compares it to that of the same species in other regions. A total of 340 whistles were analyzed. Constant (N = 115; 33.8%) and ascending (N = 99; 29.1%) whistles were the most common contours. The whistles recorded had their fundamental frequencies between 2.24 and 13.94 kHz. Whistles without inflection points were frequently emitted (N = 255; 75%). Some signals presented breaks or steps in their contour (N = 97; 28.5%). Whistle duration was short (347 ± 236 ms and 89.7% of the whistles lasted <600 ms). Seventy-eight whistle contour types were found in the total of whistles analyzed, and 27 (7.9%) of these occurred only once. Most of the whistle types were unique to a particular recording session (N = 43). The signals emitted by the rough-toothed dolphins in southeastern Brazil were characterized by low frequency modulation, short duration, low number of inflection points, and breaks. Differences in the mean values of the whistle parameters were found between this and other studies that recorded Steno bredanensis, but as in other localities, whistles above 14 kHz are rare. PMID:22559388

  16. A new genus and new bromelicolous species of Cicadellini (Insecta: Hemiptera: Cicadellidae) from Southeastern Brazil.

    PubMed

    Mejdalani, Gabriel; Quintas, Victor; Carvalho, Rachel A; Takiya, Daniela M

    2014-01-01

    A new genus, Cavichiana, is described for a new species of Cicadellini, C. bromelicola, from Southeastern Brazil (states of Rio de Janeiro and São Paulo). The new genus can be distinguished from other genera of the Cicadellini by the following combination of features: (1) head deltoid, strongly produced anteriorly; (2) ocelli located distinctly anterad of anterior eye angles; (3) aedeagus tubular, elongate, its apex with a conspicuous crown of spines; (4) paraphyses with both stalk and rami elongate, rami slender and each with basidorsal dentiform projection. The new species has a distinctive color pattern. The dorsum is dark brown to black with contrasting blue to white spots. The anterior half of the fore wings has a large, circular transcommissural yellow macula bordered by a blue to white border, the anterior portion of this macula covering the scutellum. Specimens of the new species were found on leaves of bromeliads in areas of restinga (sand dune vegetation) of the Atlantic Forest of Southeastern Brazil. Other cases of association between hemipterans and bromeliads are listed and briefly discussed. PMID:24869841

  17. Sensitivity of tree ring growth to local and large-scale climate variability in a region of Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Venegas-González, Alejandro; Chagas, Matheus Peres; Anholetto Júnior, Claudio Roberto; Alvares, Clayton Alcarde; Roig, Fidel Alejandro; Tomazello Filho, Mario

    2016-01-01

    We explored the relationship between tree growth in two tropical species and local and large-scale climate variability in Southeastern Brazil. Tree ring width chronologies of Tectona grandis (teak) and Pinus caribaea (Caribbean pine) trees were compared with local (Water Requirement Satisfaction Index—WRSI, Standardized Precipitation Index—SPI, and Palmer Drought Severity Index—PDSI) and large-scale climate indices that analyze the equatorial pacific sea surface temperature (Trans-Niño Index-TNI and Niño-3.4-N3.4) and atmospheric circulation variations in the Southern Hemisphere (Antarctic Oscillation-AAO). Teak trees showed positive correlation with three indices in the current summer and fall. A significant correlation between WRSI index and Caribbean pine was observed in the dry season preceding tree ring formation. The influence of large-scale climate patterns was observed only for TNI and AAO, where there was a radial growth reduction in months preceding the growing season with positive values of the TNI in teak trees and radial growth increase (decrease) during December (March) to February (May) of the previous (current) growing season with positive phase of the AAO in teak (Caribbean pine) trees. The development of a new dendroclimatological study in Southeastern Brazil sheds light to local and large-scale climate influence on tree growth in recent decades, contributing in future climate change studies.

  18. Population biology of the gastropod Olivella minuta (Gastropoda, Olividae) on two sheltered beaches in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Petracco, Marcelo; Camargo, Rita Monteiro; Tardelli, Daniel Teixeira; Turra, Alexander

    2014-10-01

    The structure, dynamics and production of two populations of the olivid gastropod Olivella minuta were analyzed through monthly sampling from November 2009 through October 2011 on two sandy beaches, Pernambuco (very sheltered) and Barequeçaba (sheltered) in São Paulo state (23°48'S), southeastern Brazil. On both beaches, samples were taken along five transects established perpendicular to the waterline. Parameters of the von Bertalanffy growth function were estimated for both populations from monthly length-frequency distributions. The production and turnover ratios were determined using the mass-specific growth rate method. The population on the less-sheltered Barequeçaba Beach was less abundant (120.02 ± 22.60 ind m-1) than on Pernambuco Beach (3295.30 ± 504.86 ind m-1 (±SE)), which we attribute to the greater environmental stability of the latter. Conversely, the mean length, size of the largest individual, and body mass were higher at Barequeçaba than at Pernambuco. The significant differences in the growth of individuals and the mortality rate (Z) between the beaches suggest that density-dependent processes were operating at Pernambuco Beach. The production and P/B ratio at Pernambuco (12.12 g AFDM m-1 year-1 and 1.91 year-1) were higher than at Barequeçaba (0.82 g AFDM m-1 year-1 and 1.06 year-1). The difference in production can be attributed to the higher abundance on Pernambuco, while the higher P/B ratio resulted from the scarcity of smaller individuals in the intertidal zone of Barequeçaba. The P/B ratio estimated for the Pernambuco population is the highest found so far for sandy-beach gastropods. This study reinforces the theory that biological interactions are important regulators of sheltered sandy-beach populations. Future studies with multi-beach sampling are needed to better understand the life-history variations of O. minuta along gradients of degree of exposure of sandy beaches.

  19. Habitat selection by anurofauna community at rocky seashore in coastal Atlantic Forest, Southeastern Brazil.

    PubMed

    Pontes, R C; Santori, R T; Gonçalves e Cunha, F C; Pontes, J A L

    2013-08-01

    Rocky seashores are low granitic hills distributed along the southeastern Brazilian coast with xeric-like vegetation due to the shallow soil. Knowledge on amphibian communities and their reproductive patterns is especially reduced on this kind of environment. Herein, we present a framework of two years monitoring an amphibian community at a rocky seashore environment located at the protected area of Parque Estadual da Serra da Tiririca, municipality of Niterói, state of Rio de Janeiro, Brazil. We conducted diurnal and nocturnal searches for frogs in tank bromeliads, rocky surface and shrubby vegetation. Annual pattern of breeding activity of anurans was also estimated. Individuals of the most abundant tank-bromeliad, Alcantarea glaziouana were collected and measured according to several variables to understanding the selection of bromeliads by frogs. We checked the influence of the environmental conditions on amphibian abundance, association between the bromeliads measures, and the water storage in the tank. We recorded the species: Scinax aff. x-signatus; S. cuspidatus; S. littoreus; Thoropa miliaris and Gastrotheca sp. Bromeliads were the preferential habitat used by anurans. The nocturnal habit was predominant for all species and during diurnal searches, the specimens were found sheltered in bromeliads axils. The number of calling males as well as amphibian abundance was associated with the rainiest and warmest period of the year. The species S. littoreus was observed in breeding activity in the majority of sample period. Adult calling males of T. miliaris were observed especially in the rainy season. Rainfall and temperature combined are positively correlated to the total number of captured amphibians. However, individually, rainfall was not significantly correlated, while temperature was positively correlated with the amphibian abundance. Water storage capacity by bromeliads was correlated to characteristics and size of the plant. In the rainy season, the

  20. The fate of organic carbon in colluvial soils in a subtropical agricultural catchment (Arvorezinha, Brazil)

    NASA Astrophysics Data System (ADS)

    Van de Broek, Marijn; Van Oost, Kristof; Minella, Jean; Govers, Gerard

    2016-04-01

    One of the main reasons as to why soil erosion is considered to be a carbon sink for the atmosphere is that eroded carbon is often redeposited and buried in depositional environments. However, the quantification of the magnitude of this effect is still uncertain because the residence time of soil organic carbon in depositional environments is ill defined. The latter is especially true for tropical and subtropical areas as field data for these climatic zones are largely lacking. This is an important hiatus as ca. 40% of the total global arable land is located in the (sub-)tropics [1]. We collected samples from four depositional and one stable agricultural profile in a small agricultural catchment in Arvorezinha (Brazil) where deforestation started ca. 90 yrs ago. δ13C depth profiles allowed to identify the bottom of the original A-horizon: this is because δ13C values of the buried forest soils are significantly heavier than those of the colluvial deposits. The results show that soil organic carbon contents systematically decrease with depth below the actual plough layer. This is due to the fact that a significant fraction of the organic carbon that was originally deposited is removed by mineralization from these soils over decadal time scales. As the time of deforestation is known, age-depth curves could be established. Combining this information with SOC measurements allowed for a first estimate of carbon preservation rates and showed that after 70 years ca. 25% of the deposited organic carbon is released to the atmosphere: results were very consistent across profiles. In temperate environments, the time necessary for this fraction of the deposited carbon to be mineralized is somewhat longer, i.e. 100 years [2]. This suggests that soil organic carbon may be decomposed faster in sub-tropical environments in comparison to temperate environments. This is not unexpected, given the fact that average soil temperatures are higher and soils are, in this climate

  1. Establishing a sediment budget for a small agricultural catchment in southern Brazil, to support the development of effective sediment management strategies

    NASA Astrophysics Data System (ADS)

    Minella, Jean P. G.; Walling, Desmond E.; Merten, Gustavo H.

    2014-11-01

    The rapid expansion of agriculture in Brazil has increased erosion rates and sediment yields, causing many negative environmental and economic impacts, both on- and off-site. However, to date, very few catchment-scale sediment budget investigations have been carried out in Brazil. Given the need to reduce the negative off-site impacts of increasing agricultural activity, there is an important need for such investigations in order to inform the development of effective sediment management strategies. Against this background, 137Cs measurements have been combined with measurements of sediment yield and fingerprinting the source of the fine sediment output, to establish a provisional sediment budget for a small (1.19 km2) agricultural catchment in southern Brazil. The catchment is located in an area of steep highly erodible basaltic terrain, which has been intensively cultivated with tobacco. An ongoing monitoring programme provided information on the sediment yield from the catchment and existing suspended sediment source fingerprinting investigations provided information on the main sediment sources contributing to the sediment load at the catchment outlet. 137Cs measurements have been used to estimate medium-term erosion and deposition rates along 17 transects across the cultivated slopes and to quantify sedimentation rates within valley floor sediment sinks. These data have been used to estimate sediment redistribution rates within the cultivated areas of the study catchment and sediment accumulation in the valley floor sinks. The information provided by the three primary data sources has been integrated to establish the sediment budget for the catchment over the past 57 years. The individual terms of the budget necessarily involve much uncertainty, but its closure adds confidence to the final result. The budget calculations indicate that the study catchment has a sediment delivery ratio of ∼15%. The implications of the key features of the budget for developing

  2. Long-term sediment yield from small catchment in southern Brazil affected by land use and soil management changes.

    NASA Astrophysics Data System (ADS)

    Gomes Minella, Jean Paolo; Henrique Merten, Gustavo; Alessandra Peixoto de Barros, Claudia; Dalbianco, Leandro; Ramon, Rafael; Schlesner, Alexandre

    2015-04-01

    Soil erosion and sediment yield are the main cause of soil degradation in Brazil. Despite this, there is a lack of information about the effects of the soil management on the hydrology and sediment yield at catchment scale. This study aimed to investigate the long-term relationship between the land use and sediment yield in a small catchment with significant changes in soil management, and its impacts on soil erosion and sediment yield. To account the anthropogenic and climatic effects on sediment yield were monitored precipitation, stream flow and suspended sediment concentration during thirteen years (2002 and 2014) at 10 minutes interval and the changes that occurred each year in the land use and soil management. Despite the influence of climate on the sediment yield, the results clearly show three distinct periods affected by the land use and soil management changes during this this period. In the first four years (2002-2004) the predominant land use was the tobacco with traditional soil management, where the soils are plough every year and without winter cover crop. In this period the sediment yield reached the order of 160 t.ha-1.y-1. In the period of 2005-2009, a soil conservation program introduced the adoption of minimum tillage in the catchment and the sediment yield decrease to 70 t.ha-1.y-1. In the last period (2010-2014) there was a partial return to the traditional soil management practices with an increase trend in sediment yield. However, there was also an increase in reforestation areas with positive effect in reducing erosion and sediment yield. The magnitude order of sediment yield in this period was 100 t.ha-1.y-1. The long term sediment yield data was able to demonstrate the impact of the improved management practices in reducing soil erosion and sediment yield. The results allowed a good understanding of the changing sediment dynamics and soil erosion at catchment scale.

  3. Isolation, in vitro propagation, genetic analysis, and immunogenic characterization of an Ehrlichia canis strain from southeastern Brazil

    PubMed Central

    Rieck, Susana Elisa; Ueira-Vieira, Carlos; Labruna, Marcelo Bahia; Beletti, Marcelo Emílio

    2014-01-01

    Amplification of the 16S rRNA gene from a blood sample obtained from a dog in southeastern Brazil was used to confirm a naturally acquired Ehrlichia (E.) canis infection. Following isolation and culturing of the new bacterial strain called Uberlândia, partial sequences of the dsb and p28 genes were obtained. The dsb partial sequence of the novel strain was 100% similar to dsb gene sequences of E. canis obtained from different geographic areas around the world. Conversely, the p28 partial sequence for the E. canis Uberlândia strain differed at several nucleotides from other sequences available in GenBank. To confirm the antigenic profile of the Uberlândia strain, an indirect immunofluorescence assay against E. canis antigens was performed using dog sera collected from two different areas in Brazil (Uberlândia and São Paulo). The results suggest that both antigens were able to identify animals seropositive for E. canis in Brazil since these Brazilian strains appear to be highly conserved. PMID:24136211

  4. Hesionidae Grube, 1850 (Annelida: Polychaeta) from South-Southeastern Brazil, with descriptions of four new species.

    PubMed

    Rizzo, Alexandra E; Salazar-Vallejo, Sergio I

    2014-01-01

    On the basis of extensive intertidal and subtidal samplings in South-Southeastern Brazil, five hesionid species were found; four are newly described and Podarkeopsis levisfuscina Perkins, 1984 is redescribed. Micropodarke pleijeli n. sp. differs from the other species because it lacks eyes, and by having a large number of pharynx papillae and by neurochaetal features; this species differs from M. dubia (Hessle, 1925) by lacking eyes, having a pharynx with more papillae, and by the neurochaetal features. Syllidia amaralae n. sp. resembles more closely S. armata sensu Day, 1967 (non S. armata de Quatrefages, 1865) because both have dorsal and tentacular cirri annulated or moniliform, and 10-15 pharyngeal papillae. However, S. amaralae n. sp. specimens differ from Day's ones because they have a quadrangular prostomium, by the relative size and arrangement of eyes, and by a reduced number of chaetae which are disposed in two bundles; these features are consistent and present in juveniles and mature specimens. Neogyptis nonatoi n. sp. is distinguishable from the others by having four types of neurochaetae; this species resembles N. crypta (Pleijel, 1993), and N. plurisetis (Hilbig, 1992). It differs from N. crypta by having a few acicular notochaetae with blunt tip, a small number of compound neurochaetae, simple capillary neurochaetae distally curved, and much slender notopodial and neuropodial lobes. The new species also differs from N. plurisetis by having four types of neurochaetae instead of having only falciger chaetae; there are less pharyngean papillae and they are far apart to each other, conical and shorter in N. plurisetis when compared to those of N. nonatoi n. sp., which are fringed, longer and closer among them, having some other longer lateral papillae. Oxydromus lanai n. sp. resembles O. obscurus (Verrill, 1873) as recorded by Uebelacker (1984), O. pugettensis by Hilbig (1994), O. guanicus by Hoagland (1919), and O. cf. guanicus by Hartman (1951). The

  5. Understanding the variations in the vegetation of Cabo Frio, Southeastern coast of Brazil, during the Quaternary

    NASA Astrophysics Data System (ADS)

    Macario, K.; Coe, H. H.; Gomes, J.; Oliveira, F.; Gomes, P.; Carvalho, C.; Linares, R.; Alves, E.; Santos, G. M.

    2012-12-01

    The Brazilian Southeast was formerly occupied by Atlantic forest before the arrival of Europeans in the 16th century, when deforestation slowly started to take place. To understand the variations in the vegetation of Cabo Frio during the Quaternary, and possibly identify when they roughly took place, we make use of soil phytolith identification (as proxy), stable isotopes analyses and 14C dating of soil profiles. Nowadays, those are helpful tools to reveal the palaeoenvironmental secrets hidden below-ground. The soil profile studied, which was divided in 4 horizons ranging from 10 and 115 cm in depth, was collected in the surroundings of Cabo Frio, in the Rio de Janeiro (RJ), Southeastern coast of Brazil. Its total organic carbon (TOC) varied from 0.42 to 1.11% (for the different horizons), when its δ13C values ranged from -18.81 (topsoil) to -23.72‰ (~ 80cm deep). Phytolith D/P index varied from 0.1 to 0.21. Due to the low carbon content within soil horizons, soil organic matter (SOM) fractions were chosen for isotopic analyses. Mostly of the 14C-SOM analyses were performed in a newer 14C facility, which runs a NEC 250 kV Single Stage Accelerator Mass Spectrometry system, the Radiocarbon Laboratory of the Fluminense Federal University (LAC-UFF) located in Niteroi, RJ. In brief, before measurements could be performed, the soil samples were treated with HCl 1.0M to remove carbonates, then combusted in sealed evacuated pre-baked tubes, cryogenically clean and converted to graphite (as decribed in Xu et al. 2007). In order to verify the distribution of 14C ages of different chemical soil fractions (Pessenda et al. 2001), a refractory C fraction (humin) was extracted from the topsoil horizon, and also converted to graphite following established protocols (Santos et al. 2007a,b). Due to its very low carbon mass (<<50mgC), this graphite target was processed and measured at the Keck-CCAMS Facility at University of California, Irvine. (UCI), which runs a modified NEC

  6. A Lagrangian identification of major sources of moisture for Southeastern Brazil during anomalous dry periods

    NASA Astrophysics Data System (ADS)

    Pampuch, L. A.; Ambrizzi, T.; Gimeno, L.; Drumond, A.

    2013-12-01

    The Southeast region of Brazil (SEB) comprises the states of Sao Paulo, Minas Gerais, Rio de Janeiro and Espirito Santo. Its rainy season occurs in the Austral summer.. Although less rain is registered during the winter, spring and autumn, there are years that negative precipitation anomalies were recorded in these seasons. In preliminary studies, the SEB was divided into homogenous regions with respect to precipitation. Five regions were determined: R1 (south-central state of São Paulo), R2 (north of São Paulo and southern Minas Gerais), R3 (central Minas Gerais and south-central state of Rio de Janeiro), R4 (north of the state of Minas Gerais) and R5 (north of Rio de Janeiro, the central-eastern Minas Gerais and Espírito Santo). For each region, extreme dry events were identified based on the method of consecutive dry periods. In this study, the method developed by Stohl and James (2004,2005), which use the Lagrangian particle dispersion model FLEXPART (Stohl et al.,1998), was applied with the objective to calculate and track the air particles and the atmospheric moisture backward in time to produce information on the spatial distribution of moisture sources. In this approach, the atmosphere is divided homogeneously into a large number of particles that are transported by the model which register their positions and specific humidity (q) every 6h. Increases and decreases in moisture along the trajectory can be calculated through changes in (q) with time. Adding thes changes for all particles residing in the atmospheric column over an area, we obtain (E-P) (E is the evaporation an P the precipitation per unit area).Where (E-P) is positive, the particles gain humidity and these are sources regions. For (E-P) negative, the particles lose humidity and these are sink regions. We analyzed the winter, autumn and spring from 1982 to 2009. FLEXPART were forced by ERA Interim dataset available every 6h with a 1 degree resolution. For each homogenous region in SEB (E

  7. The female reproductive cycle of the neotropical snake Atractus pantostictus (Fernandes and Puorto, 1993) from south-eastern Brazil.

    PubMed

    de Resende, F C; Nascimento, L B

    2015-06-01

    Data on reproductive activity of fossorial species are limited because the specimens are difficult to be observed and captured. Here in, we present the reproductive cycle of female Atractus pantostictus, a fossorial neotropical species, and the sexual maturity of males and females in south-eastern Brazil. The female reproductive cycle of A. pantostictus is seasonal, with vitellogenic follicles being found from September to April and eggs in November, February, March and April with the number varying between two and four. Spermatozoa were found in the lumen of the glandular and non-glandular uterus in females collected during the rainy season. Sperm storage tubules were found in the posterior infundibulum of the females, where the storage of sperm occurs for a short time. The storage may occur because mating and ovulation are dissociated. PMID:25041410

  8. Another new and threatened species of lancehead genus Bothrops (Serpentes, Viperidae) from Ilha dos Franceses, Southeastern Brazil.

    PubMed

    Barbo, Fausto E; Gasparini, João Luiz; Almeida, Antonio P; Zaher, Hussam; Grazziotin, Felipe G; Gusmão, Rodrigo B; Ferrarini, José Mário G; Sawaya, Ricardo J

    2016-01-01

    A new insular species of the genus Bothrops is described from Ilha dos Franceses, a small island off the coast of Espírito Santo State, in southeastern Brazil. The new species differs from mainland populations of B. jararaca mainly by its small size, relative longer tail, relative smaller head length, and relative larger eyes. The new species is distinguished from B. alcatraz, B. insularis and B. otavioi by the higher number of ventral and subcaudal scales, relative longer tail and smaller head. The new species is highly abundant on the island, being nocturnal, semiarboreal, and feeding on small lizards and centipeds. Due its unique and restricted area of occurrence, declining quality of habitat, and constant use of the island for tourism, the new species may be considered as critically endangered. PMID:27394563

  9. Helicometrina nimia Linton, 1910 (Digenea: Opecoelidae) in dusky grouper Epinephelus marginatus (Lowe, 1834) (Teleostei: Serranidae) from southeastern Brazil.

    PubMed

    Roumbedakis, K; Marchiori, N C; Garcia, P; Pereira Junior, J; Castro, L A S; Martins, M L

    2014-05-01

    Helicometrina nimia (Opecoelidae) is a digenean with wide distribution. Fish families most commonly used as hosts for H. nimia are Serranidae, Pomodasydae, Scorpaenidae and Clinidae. In the present study, a new host and a new host locality are presented for the species. A description of the studied specimens, besides comments concerning its taxonomic status and biometrically compared tables of H. nimia reports are given. The taxonomic status of members of Helicometrina has been questionable. The greatest controversy for the genus seems to be related to the validity of diagnostic features, especially in regard to the number of testes. In the present study, all studied specimens presented a permanent and steady number of testes (n=9) and therefore its use as a diagnostic character is supported by the present authors. Epinephelus marginatus is considered a new host for Helicometrina nimia, and São Paulo state, southeastern Brazil, a new locality for the species. PMID:25166333

  10. Contributions to the Dart versus Arrow Debate: New Data from Holocene Projectile Points from Southeastern and Southern Brazil.

    PubMed

    Okumura, Mercedes; Araujo, Astolfo G M

    2015-01-01

    Lithic bifacial points are very common in the southern and southeastern regions of the Brazilian territory. Dated from Early to Late Holocene, these artifacts have not been studied in terms of their propulsion system. Given the characteristics of the bow and arrow compared to the atlatl and dart, there are important differences in the size and weight of arrowheads and dart points. Applying the techniques proposed by Shott (1997), Bradbury (1997), Fenenga (1953), Hughes (1998), and Hildebrandt and King (2012) to specimens recovered from eight sites dating from the early to the late Holocene, this work aims to present preliminary results to better understand the potential presence of darts and arrows in southeastern and southern Brazil. There was a variation in the results according to the application of different techniques. At least one set of points, dated from the Early Holocene, presented quite a high proportion of specimens classified as arrows, indicating the presence of points that could be used as arrowheads. PMID:26648546

  11. River water quality of the River Cherwell: an agricultural clay-dominated catchment in the upper Thames Basin, southeastern England.

    PubMed

    Neal, Colin; Neal, Margaret; Hill, Linda; Wickham, Heather

    2006-05-01

    The water quality of the River Cherwell and a tributary of it, the Ray, are described in terms of point and diffuse sources of pollution, for this rural area of the upper Thames Basin. Point sources of pollution dominate at the critical ecological low flow periods of high biological activity. Although the surface geology is predominantly clay, base flow is partly supplied from springs in underlying carbonate-bearing strata, which influences the water quality particularly with regards to calcium and alkalinity. The hydrogeochemistry of the river is outlined and the overall importance of urban point sources even in what would normally be considered to be rural catchments is stressed in relation to the European Unions Water Framework Directive. Issues of phosphorus stripping at sewage treatment works are also considered: such stripping on the Cherwell has reduced phosphorus concentrations by about a factor of two, but this is insufficient for the needs of the Water Framework Directive. PMID:16253306

  12. Monitoring Two Small Catchments to Evaluate Effects of No-Tillage Agricultural Management in São Paulo State, Brazil

    NASA Astrophysics Data System (ADS)

    Figueiredo, R. D. O.; Gonçalves, A. O.; Melo, A. D. S.; de Bona, F. D.; Hernani, L. C.

    2015-12-01

    In recent years, declines in water and soil quality have been observed in areas of Brazil where no-till agriculture had been previously implemented. Poor soil management associated with the absence of public policies has caused soil erosion, because many farmers are moving back from no-till to traditional cultivation for faster economic gains. A research project - SoloVivo Project - leaded by Embrapa (Brazilian Agricultural Research Corporation) in partnership with Itaipu Binacional aims to develop and validate, in a participatory way, tools to evaluate the technical performance of soil and water management at the rural properties that practice no-till agriculture. In this context we have selected two paired small (< 100 ha) catchments in the Paranapanema region, São Paulo State, where no-till management is practiced at two different degrees of effectiveness. In the figure bellow it can be seen a scene of one of the two studied catchments. For monitoring rainfall, soil solution and stream water, each catchment will be equipped with a programmable datalogger (with cell phone communication for data collection) linked to: a high intensity tipping bucket rain gage; a reflectometer to monitor soil volumetric water content, bulk electric conductivity and temperature; a radar water level sensor; a turbidity sensor; and an electric conductivity-temperature probe. We expect that stream flow and sediment generation, besides water quality (measured by conductivity) may serve as indicators of the benefits of no-tillage agriculture done more or less well. The results of this study will be used to stimulate discussions at workshops with the farmers who participate in a rural producers association in the region. In addition this and other results can be used to help the Brazilian National Water Agency (ANA) decide about applying no-till agricultural management systems in its programs of payment for environmental services.

  13. Sediments in urban river basins: identification of sediment sources within the Lago Paranoá catchment, Brasilia DF, Brazil - using the fingerprint approach.

    PubMed

    Franz, C; Makeschin, F; Weiß, H; Lorz, C

    2014-01-01

    The development of effective sediment management strategies is a key requirement in tropical areas with fast urban development, like Brasilia DF, Brazil, because of the limited resources available. Accurate identification and management of sediment sources areas, however, is hampered by the dearth of reliable information on the primary sources of sediment. Few studies have attempted to quantify the source of sediment within fast urbanizing, mixed used, tropical catchments. In this study, statistically verified composite fingerprints and a multivariate mixing model have been used to identify the main land use specific sources of sediment deposited in the artificial Lago Paranoá, Central Brazil. Because of the variability of urban land use types within the Lago Paranoá sub-catchments, the fingerprinting approach was additionally undertaking for the Riacho Fundo sub-catchment. The main contributions from individual source types (i.e. surface materials from residential areas, constructions sites, road deposited sediment, cultivated areas, pasture, farm tracks, woodland and natural gullies) varied between the whole catchment and the Riacho Fundo sub-catchment, reflecting the different proportions of land uses. The sediments deposited in the silting zones of the Lago Paranoá originate largely from urban sources (85 ± 4%). Areas with (semi-) natural vegetation and natural gullies contribute 10 ± 2% of the sediment yield. Agricultural sites have only a minor sediment contribution of about 5 ± 4% within the whole catchment. Within the Riacho Fundo sub-catchment there is a significant contribution from urban (53 ± 4%) source, such as residential areas with semi-detached housings (42 ± 3%) with unpaved roads (12 ± 3%) and construction sites (20 ± 3%) and agricultural areas (31 ± 2%). The relative contribution from land use specific sources to the sediment deposition in the silting zone of the Lago Paranoá demonstrated that most of the sediment is derived from

  14. Hepatozoon spp. infections in wild rodents in an area of endemic canine hepatozoonosis in southeastern Brazil.

    PubMed

    Demoner, Larissa de Castro; Magro, Natalia Mizuhira; da Silva, Maria Regina Lucas; de Paula Antunes, João Marcelo Azevedo; Calabuig, Cecilia Irene Pérez; O'Dwyer, Lucia Helena

    2016-07-01

    Hepatozoon canis is a tick-borne parasite that occurs worldwide. In rural areas of Brazil, H. canis vectors remain unknown, which has led to speculation about alternative routes of transmission. Small rodents can play a role in the transmission (via predation) of Hepatozoon americanum, which led us to question whether predation might be an alternative mode of transmission for H. canis. Thus, this study investigated whether Hepatozoon spp. are present in wild small rodents in forest fragments that surround rural areas in Botucatu County, São Paulo, Brazil, where canine hepatozoonosis is endemic. The study included blood samples from 158 dogs, which were screened by microscopy and molecular analysis. Blood samples and tissues from 67 rodents were obtained for histopathology and molecular detection. The prevalence of H. canis was high (66.45%) in dogs from rural areas of Botucatu, São Paulo, Brazil. The molecular analysis showed that wild rodent species in Brazil were infected with Hepatozoon spp. other than H. canis. Therefore, although the hypothesis that sylvatic rodents act as reservoirs for H. canis was not supported, the presence of monozoic cysts in the rodents suggests that, in addition to intermediate hosts, wild small rodents in Brazil might act as paratenic hosts of Hepatozoon spp. because they harbor infective stages for intermediate host predators. PMID:27091081

  15. Growth and reproductive dynamics of the South American red shrimp, Pleoticus muelleri (Crustacea: Solenoceridae), from the southeastern coast of Brazil

    NASA Astrophysics Data System (ADS)

    Castilho, A. L.; Wolf, M. R.; Simões, S. M.; Bochini, G. L.; Fransozo, V.; Costa, R. C.

    2012-12-01

    The increase in the fishing fleet in southeastern Brazil and the decrease in the landings of profitable shrimp species have contributed to the incorporation of additional species into those fisheries, such as Pleoticus muelleri. The goal of the present study is to investigate the growth and reproductive dynamics of P. muelleri in the Southeastern coast of Brazil over a period of two years. Monthly collections were conducted in Ubatuba (UB) and Caraguatatuba (CA) using a commercial shrimp fishing boat equipped with “double-rig” nets. Each region was divided into 7 sampling stations up to 35 m deep. Population parameters from size frequency distributions (carapace length = CL), growth, longevity, sex ratio, and abundance of individuals in each life period (demographic class), from both sampling areas were analyzed and compared. The relationship between abiotic factors and abundance of each demographic class was assessed using a Canonical Correlation Analysis (CCorrA). A total of 19,816 individuals were collected, of which 5341 were measured, with an estimated longevity of 2.02 (UB) and 2.15 (CA) years for females and 1.80 (UB) and 1.96 (CA) years for males. There was a statistically significant bias in sex ratio toward females (Chi-square test, p < 0.05) in both regions. The CCorrA resulted in a canonical correlation coefficient of 0.32 (p < 0.00001). Both temperature and grain size composition of the sediment showed high correlation mainly with the presence of reproductive females, followed spermatophore-bearing males and recruits. In general, these demographic classes were most common in conditions of low temperature and fine sediments. These findings, as well as other studies carried out in colder regions with the same species, are consistent with the classical paradigm of lower longevity at lower latitudes. However, our results also suggest that this species maintained abiotic preference as populations located in cold temperate regions, mainly with

  16. Metal bioaccumulation in edible target tissues of mullet (Mugil liza) from a tropical bay in Southeastern Brazil.

    PubMed

    Hauser-Davis, Rachel Ann; Bordon, Isabella C A C; Oliveira, Terezinha F; Ziolli, Roberta Lourenço

    2016-07-01

    The present study aimed to investigate metal bioaccumulation in mullet (M. liza) from a tropical bay located in Southeastern Brazil, comparing a previously considered reference site to a known contaminated area of the bay, as well as to conduct human health risk assessments with regard to the consumption of this species. The metal concentrations were compared to the maximum residue level (MRL) in foods established by the different national and international regulatory agencies, and the Provisional Tolerable Daily Intake (PTDI) was determined and compared to reference values. Chromium (Cr), Zinc (Zn), Copper (Cu), Manganese (Mn), Nickel (Ni), Cadmium (Cd) and Lead (Pb) concentrations were determined in the gills, muscle and liver of 28 mullet by ICP-MS after acid digestion. Certain metals exceeded MRL guidelines established by different regulatory agencies, indicating human health risks associated to these metals. PTDI values, however, did not exceed corresponding metal values proposed by the World Health Organization. The metal concentrations found in the mullet samples indicate that the previously considered reference site is now showing signs of anthropogenic contamination. PMID:27259350

  17. Long-term trends in hydrochemistry in the Paraíba do Sul River, southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Ovalle, A. R. C.; Silva, C. F.; Rezende, C. E.; Gatts, C. E. N.; Suzuki, M. S.; Figueiredo, R. O.

    2013-02-01

    SummaryThe Paraíba do Sul watershed is an important hydrological resource for southeastern Brazil, that has undergone extensive land use changes related to industrial, agricultural and urban activities. Over 11 years, between 1997 and 2007, a long-term study was conducted to evaluate hydrochemical variation in the basin outlet through estimations of annual fluxes and identification of their controlling factors. River water was classified as Na-HCO3, with TDS ranging from 32 to 132 mg L-1. Variation between seasons was found: cations, total alkalinity, electrical conductivity, dissolved oxygen, nitrate and chlorophyll "a" had increased values the during low discharge period, while concentrations of DOC, ammonium, nitrite, phosphate and SPM had increased values during the high discharge period. Chloride, sulfate, silica and pH showed no clear relationship with discharge. These patterns also were correlated with hydrological flow paths originating from different sources. Wavelet decomposition was used to characterize precipitation anomalies largely associated both with long-term climate factors (i.e. ENSO) and short-term climate responses from the two discharge periods that were studied. Distinct responses of fluvial hydrochemistry were observed including ENSO-induced fluctuation to be particularly strong for DOC, with annual flux varying approximately 60% around measured median value.

  18. Links between riparian landcover, instream environment and fish assemblages in headwater streams of south-eastern Brazil

    USGS Publications Warehouse

    Cruz, Bruna B.; Miranda, Leandro E.; Cetra, Mauricio

    2013-01-01

    We hypothesised and tested a hierarchical organisation model where riparian landcover would influence bank composition and light availability, which in turn would influence instream environments and control fish assemblages. The study was conducted during the dry season in 11 headwater tributaries of the Sorocaba River in the upper Paraná River Basin, south-eastern Brazil. We focused on seven environmental factors each represented by one or multiple environmental variables and seven fish functional traits each represented by two or more classes. Multivariate direct gradient analyses suggested that riparian zone landcover can be considered a higher level causal factor in a network of relations that control instream characteristics and fish assemblages. Our results provide a framework for a hierarchical conceptual model that identifies singular and collective influences of variables from different scales on each other and ultimately on different aspects related to stream fish functional composition. This conceptual model is focused on the relationships between riparian landcover and instream variables as causal factors on the organisation of stream fish assemblages. Our results can also be viewed as a model for headwater stream management in that landcover can be manipulated to influence factors such as bank composition, substrates and water quality, whereas fish assemblage composition can be used as indicators to monitor the success of such efforts.

  19. Helminth fauna of two species of Physalaemus (Anura: Leiuperidae) from an undisturbed fragment of the Atlantic rainforest, southeastern Brazil.

    PubMed

    Toledo, Gislayne M; Aguiar, Aline; Silva, Reinaldo J; Anjos, Luciano A

    2013-10-01

    Two amphibian species, Physalaemus cuvieri and Physalaemus olfersii, from Serra do Mar State Park, which is an old-growth environment of the Atlantic Rainforest in southeastern Brazil, were surveyed for endoparasites. Hosts were sampled in 2 ponds; each was colonized by only 1 Physalaemus species. The overall prevalence of helminths was high and similar in both amphibian species. The mean intensity of infection in P. olfersii did not differ statistically from that in P. cuvieri . Nine helminth species were found: 2 acanthocephalans, 1 cestode, and 6 nematodes. Parasite richness in the 2 host species was similar. The composition of helminth fauna differed but the 2 hosts shared the most prevalent taxon of nematode (an unidentified species of Cosmocercidae). All helminth species exhibited an aggregated distribution pattern in the host species. The present results demonstrate relatively low species richness and the dominance of generalist parasite species. This study contributes to knowledge regarding the structure and composition of the helminth community in anurans. PMID:23409941

  20. Lifespan and population dynamics of the endemic South American shrimp Artemesia longinaris (Crustacea: Penaeidae) in southeastern Brazil.

    PubMed

    Castilho, Antonio L; Grabowski, Raphael C; Simões, Sabrina M; Santos, Ana Paula F; Costa, Rogério C; Fransozo, Adilson

    2015-01-01

    The present study investigated the growth, longevity and reproductive dynamics of Artemesia longinaris in the southeastern coast of Brazil over a two-year period. Monthly collections were conducted in Ubatuba and Caraguatatuba using a shrimp fishing boat equipped with "double-rig" nets. Each region was divided into 7 sampling stations up to 35 m deep. Size frequency distributions, growth, longevity, sex ratio, and abundance of individuals in each demographic class, were compared. The relationship between abiotic factors and abundance of each demographic class was assessed using a Canonical Correlation Analysis. A total of 64,641 individuals were collected (6,928 measured) with an estimated longevity of 1.30 (Ubatuba) and 1.14 (Caraguatatuba) years for females and 1.03 years for males in both regions. There was a statistically significant bias in sex ratio toward females (Chi-squared test, p < 0.05) in both regions. The Canonical Correlation Analysis resulted in a canonical correlation coefficient of 0.31 (p = 0.00002). Salinity and temperature showed high correlation mainly with the presence of reproductive females. In general, this demographic class was most common in conditions of low temperature and high salinity. These findings, as well as other studies carried out in colder regions with the same species, are consistent with classical latitudinal paradigm. PMID:26628032

  1. Aechmea pectinata: a hummingbird-dependent bromeliad with inconspicuous flowers from the rainforest in south-eastern Brazil.

    PubMed

    Canela, Maria Bernadete Ferreira; Sazima, Marlies

    2003-11-01

    The pollination biology of Aechmea pectinata (Bromeliaceae) was studied in a submontane rainforest in south-eastern Brazil. This species has a mainly clumped distribution and its aggregated individuals are likely to be clones. From October to January, during the flowering period, the distal third of its leaves becomes red. The inflorescence produces 1-15 flowers per day over a period of 20-25 d. The flowers are inconspicuous, greenish-white coloured, tubular shaped with a narrow opening, and the stigma is situated just above the anthers. Anthesis begins at 0400 h and flowers last for about 13 h. The highest nectar volume and sugar concentration occur between 0600 and 1000 h, and decrease throughout the day. Aechmea pectinata is self-incompatible and therefore pollinator-dependent. Hummingbirds are its main pollinators (about 90 % of the visits), visiting flowers mainly in the morning. There is a positive correlation between the number of hummingbird visits per inflorescence and the production of nectar, suggesting that the availability of this resource is important in attracting and maintaining visitors. The arrangement of the floral structures favours pollen deposition on the bill of the hummingbirds. Flowers in clumps promote hummingbird territoriality, and a consequence is self-pollination in a broader sense (geitonogamy) as individuals in assemblages are genetically close. However, trap-lining and intruding hummingbirds promote cross-pollination. These observations suggest that successful fruit set of A. pectinata depends on both the spatial distribution of its individuals and the interactions among hummingbirds. PMID:14573525

  2. The Alegre Lineament and its role over the tectonic evolution of the Campos Basin and adjacent continental margin, Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Calegari, Salomão Silva; Neves, Mirna Aparecida; Guadagnin, Felipe; França, George Sand; Vincentelli, Maria Gabriela Castillo

    2016-08-01

    The structural framework and tectonic evolution of the sedimentary basins along the eastern margin of the South American continent are closely associated with the tectonic framework and crustal heterogeneities inherited from the Precambrian basement. However, the role of NW-SE and NNW-SSE structures observed at the outcropping basement in Southeastern Brazil and its impact over the development of those basins have not been closely investigated. In the continental region adjacent to the Campos Basin, we described a geological feature with NNW-SSE orientation, named in this paper as the Alegre Fracture Zone (AFZ), which is observed in the onshore basement and can be projected to the offshore basin. The main goal of this work was to study this structural lineament and its influence on the tectonic evolution of the central portion of the Campos Basin and adjacent mainland. The onshore area was investigated through remote sensing data joint with field observations, and the offshore area was studied through the interpretation of 2-D seismic data calibrated by geophysical well logs. We concluded that the AFZ occurs in both onshore and offshore as a brittle deformation zone formed by multiple sets of fractures that originated in the Cambrian and were reactivated mainly as normal faults during the rift phase and in the Cenozoic. In the Campos Basin, the AFZ delimitates the western side of the Corvina-Parati Low, composing a complex fault system with the NE-SW faults and the NW-SE transfer faults.

  3. Investigation of thermostable metalloproteins in Perna perna mussels from differentially contaminated areas in Southeastern Brazil by bioanalytical techniques.

    PubMed

    Lavradas, Raquel Teixeira; Rocha, Rafael Christian Chávez; Saint' Pierre, Tatiana Dillenburg; Godoy, José Marcus; Hauser-Davis, Rachel Ann

    2016-03-01

    Metallomic studies regarding environmental contamination by metals are of value in elucidating metal uptake, trafficking, accumulation and metabolism in biological systems. Many proven bioindicator species, such as bivalves, have not yet, however, been well-characterized regarding their metalloprotein expression in response to environmental contaminants. In this context, the aim of the present study was to investigate metalloprotein expressions in the thermostable protein fraction of muscle tissue and digestive glands from mussels (Perna perna) from three differentially metal-contaminated sites in Southeastern Brazil in comparison with a reference site. The thermostable protein fractions were analyzed by SDS-PAGE and SEC-HPLC-ICP-MS. Metal content was also determined in both the crude and the purified extracts. Several inter-organ differences were observed, which is to be expected, while inter-site differences regarding thermostable protein content were also verified, indicating accumulation of these elements in muscle tissue and digestive glands and disruption of homeostasis of essential elements, with detoxification attempts by metal-bound proteins, since all metalloproteins present in both matrices eluted bound to at least one non-essential metal. These results are also noteworthy with regard to the adopted reference site, that also seems to be contaminated by toxic metals. PMID:26854248

  4. Fish gills alterations as potential biomarkers of environmental quality in a eutrophized tropical river in south-eastern Brazil.

    PubMed

    Nascimento, A A; Araújo, F G; Gomes, I D; Mendes, R M M; Sales, A

    2012-06-01

    Gill anomalies in three common fish species of different taxonomic order, habitat dwelling and feeding habits (one Characiformes, Oligosarcus hepsetus; one Siluriformes, Hypostomus auroguttatus; and one Perciformes, Geophagus brasiliensis) from a eutrophized tropical river in south-eastern in Brazil were compared. The aim of this study was to search for sentinel species that could be used as potential biomarkers of environmental quality. Most fish had gills with histological changes, namely epithelial lifting, interstitial oedema, leucocyte infiltration, hyperplasia of the epithelial cells, lamellar fusion, vasodilatation and necrosis. On the other hand, lamellar blood congestion and lamellar aneurysm, which are more serious and often irreversible changes, were recorded for the water column carnivorous O. hepsetus and, to a lesser extent, for the bottom-dwelling detritivorous H. auroguttatus. A histopathological alteration index (HAI) based on the occurrence and severity of gills anomalies indicated that O. hepsetus (mean score = 11.4) had significantly higher values (Kruskall-Wallis H(2,41) = 15.95, P = 0.0003) compared with G. brasiliensis (mean score = 7.0). Overall, the omnivorous G. brasiliensis had comparatively lesser occurrence of most gill anomalies compared with other two species, being less suitable as biomarker of environmental quality. In contrast, the water column-dweller O. hepsetus (water column) and the bottom-dweller H. auroguttatus had gills most susceptible to changes, making them more suitable for using as histological biomarkers of the environmental quality in entrophized tropical rivers. PMID:22211803

  5. Parasite fauna of wild and cultured dusky-grouper Epinephelus marginatus (Lowe, 1834) from Ubatuba, southeastern Brazil.

    PubMed

    Roumbedakis, K; Marchiori, N C; Paseto, Á; Gonçalves, E L T; Luque, J L; Cepeda, P B; Sanches, E G; Martins, M L

    2013-11-01

    This study aimed at identifying and quantifying the parasites of wild and cultured dusky grouper Epinephelus marginatus. During a year and thereby all four seasons, 20 wild and 20 cultured groupers were examined for the presence of parasites, except in the last season, in which 19 wild and 20 cultured fish were examined, totalling 159 groupers analysed from Ubatuba, southeastern Brazil. Prevalence, mean intensity of infection, mean abundance and mean relative dominance were calculated. Five species of parasites were identified in fish from both origins: Pseudorhabdosynochus beverleyburtonae (Monogenea), Neobenedenia melleni (Monogenea), Pseudempleurosoma sp. (Monogenea), Helicometrina nimia (Digenea) and larvae of Contracaecum sp. (Nematoda). The prevalence of ectoparasites, in most cases, was higher than endoparasites. The most abundant parasite was the monogenea Pseudorhabdosynochus beverleyburtonae in both wild and cultured fish, along all seasons. Neobenedenia melleni was observed in wild and cultured fish in all seasons, with a gradual increase in the number of parasites from the coldest to the hottest seasons, with the highest prevalence and mean intensity in the summer. Helicometrina nimia was found in all seasons in both wild and cultured fish, except for summer, where its presence was detected only in wild fish. Pseudempleurosoma sp. and larvae of Contracaecum sp. showed low prevalence occurring in wild and cultured fish in the autumn and spring, respectively. This study revealed high intensities of potentially pathogenic parasites that could favour disease outbreaks in culture conditions. PMID:24789405

  6. Rovearinids (stemless crinoids) in the Albian carbonates of the offshore Santos Basin, southeastern Brazil: stratigraphic, palaeobiogeographic and palaeoceanographic significance

    NASA Astrophysics Data System (ADS)

    Dias-Brito, D.; Ferré, B.

    2001-06-01

    Microfacies analysis of marine carbonates cored by Petrobras well 1-SPS-6 in the offshore Santos Basin (southeastern Brazil) has revealed a remarkable fossil assemblage of calpionellids (colomiellids), favusellids, hedbergellids, globigerinelloidids, buliminids, radiolarians, inoceramid prisms, roveacrinids, and saccocomids(?) preserved in lower Albian calcimudstones-wackestones of the lower part of the Guarujá Formation. This assemblage represents an allochtonous accumulation in a deep neritic to shallow bathyal hypoxic environment. Besides 'saccocomid-like' sections, the only determinable sections of roveacrinids are thecal plates of Poecilocrinus dispandus elongatus Peck, 1943. This species was previously only known from the Weno Formation of Texas. The Brazilian material extends its records farther south from at least the lower Albian, which then represents the earliest occurrence of this peculiar family in the South Atlantic region. Taking into account their Albian global distribution and the location of their oldest representative (Hauterivian near Alicante, Spain), the Roveacrinidae dispersed westward throughout all of Cretaceous Tethys. The Tethyan origin of Roveacrinidae is further evidence that, during late Aptian-Albian times, the northern South Atlantic (north of the Walvis-São Paulo Ridge) was supplied by a Tethyan water mass.

  7. Humoral immune response in dogs and cats vaccinated against rabies in southeastern Brazil

    PubMed Central

    2013-01-01

    Background Brazil holds annual nationwide public campaigns to vaccinate dogs and cats against rabies. The presence of rabies antibodies in these animals, which are among the main transmitters of rabies to humans, is a good indicator that they are immunized and protected. Methods In the present study we analyzed 834 serum samples from dogs and cats from the Southeast of Brazil (Presidente Prudente and Dracena cities), 12 months after the 2009 vaccination campaign. We used the technique known as rapid fluorescent focus inhibition test (RFFIT) and considered reactant those sera with values higher 0.5 IU/mL. Results and discussion Reactant sample results in Presidente Prudente were 153 (51.0%) for dogs and 59 (32.6%) for cats, and in Dracena 110 (52.1%) for dogs and 71 (50.0%) for cats. We discussed vaccine coverage of animals involved in this experiment, and observed low titers < 0.5 IU/mL, especially in cats from Presidente Prudente. Conclusion According to the results presented in our experiment, we suggest that titers below 0.5 IU/mL are worrisome and that, for multiple reasons, animals should be immunized against rabies in the period between public vaccination campaigns. Hence, the desired vaccine coverage was not accomplished, especially among cats from Presidente Prudente. PMID:23899101

  8. Brachyuran and anomuran crabs associated with Schizoporella unicornis (Ectoprocta, Cheilostomata) from southeastern Brazil.

    PubMed

    Alves, Douglas F R; Barros-Alves, Samara P; Lima, Daniel J M; Cobo, Valter J; Negreiros-Fransozo, Maria Lucia

    2013-03-01

    The main goals of this investigation were to describe the community structure of anomuran and brachyuran crabs inhabiting reefs constituted by colonies of Schizoporella unicornis, and to provide a species importance ranking for this community. Collections were carried out on S. unicornis reefs at two-month intervals from May 2003 to May 2004, in the rocky sublittoral of the southeastern Brazilian coast. Relative abundance and occurrence were used to rank these species in the hierarchy importance. A total of 2,018 individuals were obtained, in 11 families, 22 genera and 31 species. Porcellanidae and Pilumnidae were the most abundant families, comprising respectively almost 60% and 15% of individuals sampled. The species ranking indicated four main groups A, B, C and D, with group A subdivided. Subgroup A1 contained 9 species, including the species of greatest ecological importance for community regarding abundance and occurrence. The great abundance of crabs associated with S. unicornis seems to be the result of its recognized importance during the crab developmental cycle, and as shelter and food for some Decapod species. These observations reveal the importance of conserving the areas occupied by these reef colonies, which appear to be an important environment for maintaining local biodiversity. PMID:23538959

  9. OSL dating of sediments from a mountainous river in southeastern Brazil: Late Cenozoic tectonic and climatic implications

    NASA Astrophysics Data System (ADS)

    Junior, Antônio Pereira Magalhães; Cherem, Luis Felipe Soares; Barros, Luiz Fernando de Paula; Santos, Gisele Barbosa dos

    2011-09-01

    The upper Das Velhas River basin is located in the central portion of the Quadrilátero Ferrífero in southeastern edge of São Francisco Craton, southeastern Brazil. Its drainage network has a strong lithostructural influence and mountainous river segments crossing different tectonic blocks. The neotectonic activity in this cratonic edge is associated with epirogenetic Brazilian Shield uplift and with local and regional differential movements of crustal blocks due to WNW migration of South-American plate. This process cause an intraplate transfer of tectonic efforts, forcing the reactivation of old faults (NW-SE and NE-SW) and the generation of recent ones (E-W). Using optically stimulated luminescence (OSL) dating and fluvial deposit data, this paper focuses on the late Cenozoic evolution of this mountainous river basin, relating it to tectonic and climatic forcing. Even with few records of ancient alluvial deposits as a result of intense dissection, three levels of river terraces were identified in some sites along the valley: a higher terrace level (T3), a cut-in-bedrock terrace of ~ 48 ka; an intermediate terrace level (T2) of ~ 7.5 ka; and a lower terrace level (T1), of ~ 1 ka. The T2 is found along the valley as a cut-in-bedrock terrace or as a fill terrace, and is found T1 as a cut-in-bedrock terrace or as a nested fill terrace or even overlapping T2 sediments. The diverse relation between these terraces may be related to unequal fluvial downcutting. We identified three main downcutting periods: (i) before T3; (ii) from T3 to T2, related to Late Pleistocene regional tectonics; and (iii) from T2 to T1, which was a response to tectonics and climate change in the early Holocene. These stages of more intense downcutting should be a response to uplift pulses. In the most active blocks, cut-in-bedrock terraces show a greater unevenness in relation to lower levels, while in the most stable blocks, T1 is found as a nested fill terrace or overlapping T2.

  10. Disseminated Leishmaniasis by Leishmania viannia Subgenus: A Series of 18 Cases in Southeastern Brazil

    PubMed Central

    Vernal, Sebastian; De Paula, Natalia A.; Gomes, Ciro M.; Roselino, Ana Maria

    2016-01-01

    Background. Disseminated leishmaniasis (DL) is an emerging clinical form of American tegumentary leishmaniasis (ATL) that occurs mainly in Northeastern Brazil. This study describes 18 cases where DL has not yet been reported. Methods. Disseminated leishmaniasis cases were extracted from ATL recorded cases between 1987 and March 2015. Disseminated leishmaniasis identification was based on ≥10 mixed-type lesions, located in ≥2 body parts. Results. Eighteen (5.4%) patients were identified as DL. Polymerase chain reaction followed by enzymatic digestion confirmed Leishmania viannia subgenus in 17 patients; amastigotes forms were identified in another one. Conclusions. Considering that DL diagnosis and management is challenging, clinicians must be aware of this emerging clinical form of the disease. PMID:26848483

  11. A new Amphisbaena (Squamata: Amphisbaenidae) from southern Espinhaço Range, southeastern Brazil.

    PubMed

    Costa, Henrique C; Resende, Flávia C; Teixeira, Mauro; Dal Vechio, Francisco; Clemente, Cinara A

    2015-01-01

    A new species of Amphisbaena is described from a semi-deciduous forest in Conceição do Mato Dentro, southern Espinhaço Range, Minas Gerais, Brazil. The following combined characters can diagnose the new species from all congeners: head round-shaped; two or three precloacal pores sequentially arranged; 190-199 body annuli; 2-3 lateral annuli; 23-25 caudal annuli; autotomy sites on caudal annuli 7-9; 12-14 dorsal segments on midbody annulus; 14-16 ventral segments on midbody annulus; three supralabials; three infralabials; postmalar row present or absent; dorsum light brown, with cream intersegmental sutures; venter cream. To date, the new species is known only from the Espinhaço Range, highlighting the importance of conservation actions for these mountains. PMID:26131637

  12. Overlapping Toxoplasma gondii Genotypes Circulating in Domestic Animals and Humans in Southeastern Brazil

    PubMed Central

    Silva, Letícia A.; Andrade, Renata O.; Carneiro, Ana Carolina A. V.; Vitor, Ricardo W. A.

    2014-01-01

    Although several Toxoplasma gondii genotyping studies have been performed in Brazil, studies of isolates from animals in the state of Minas Gerais are rare. The objective of this study was to conduct a genotypic characterization of T. gondii isolates obtained from dogs, free-range chickens, and humans in Minas Gerais and to verify whether the T. gondii genotypes circulating in domestic animals correspond to the genotypes detected in humans. Genetic variability was assessed by restricted fragment length polymorphism at 11 loci (SAG1, 5′+3′SAG2, SAG2 alt, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). Twelve different genotypes were identified among the 24 isolates studied, including 8 previously identified genotypes and 4 new genotypes. The genetic relationship of the 24 T. gondii isolates, together with the genotypes previously described from 24 human newborns with congenital toxoplasmosis, revealed a high degree of similarity among the genotypes circulating in humans and animals in Minas Gerais. The most common genotypes among these species were BrII, BrIII, ToxoDB #108, and ToxoDB #206. Restricted fragment length polymorphism at the CS3 locus of these 48 isolates showed that the majority of isolates presented alleles I (50%) or II (27%). Isolates harboring allele III at the CS3 locus presented low virulence for mice, whereas those harboring alleles I or II presented higher virulence. These results confirm the utility of marker CS3 for predicting the virulence of Brazilian isolates of T. gondii in mice. No association was found between the allele type and clinical manifestations of human congenital toxoplasmosis. This is the first report of T. gondii genotyping that verifies the overlapping genotypes of T. gondii from humans and animals in the same geographic region of Brazil. Our results suggest that there is a common source of infection to the species studied, most likely oocysts contaminating the environment. PMID:24587295

  13. Fission track analysis of apatites from São Francisco craton and Mesozoic alcaline-carbonatite complexes from central and southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Amaral, G.; Born, H.; Hadler, J. C. N.; Iunes, P. J.; Kawashita, K.; Machado, D. L.; Oliveira, E. P.; Paulo, S. R.; Tello, C. A. S.

    1997-07-01

    Thermal histories on seven Brazilian apatites were obtained by fission track analysis using Monte Carlo simulations. The apatites were collected from two distinct geotectonic provinces. One group, originated from São Francisco craton, represents a typical cratonic domain with Proterozoic and Eopaleozoic rocks and yielded Permo-Triassic ages (counted since the instant when temperature was low enough so that the damage produced by fission tracks in apatite started to be preserved). The common thermal history accepted by all samples of this group is a linear cooling from ~90 to ~25 °C for the last 240 Ma, in agreement with present day thermal gradient and denudation rates. The other group, from Mesozoic alkaline-carbonatite complexes, in central and southeastern Brazil, yielded Cretaceous ages, close to those of the intrusions. For the samples of central Brazil, fission track analysis suggests a slow cooling from ~95 ° to ~85 °C between 90 and 60 Ma ago, followed by a faster cooling from ~85 ° to ~27 °C for the last 60 Ma. Otherwise, two trends exist for the samples of southeastern Brazil. The primary one is an increase in temperature from ~75 ° to ~95 °C, which occurred between 140 and 60 Ma ago. In this period, there is also another trend: a cooling from ~100 ° to ~80 °C. However, both trends are followed by a common thermal history during the last 60 Ma: a cooling from approximately ~80 ° to ~25 °C.

  14. Clinical consequences of Tityus bahiensis and Tityus serrulatus scorpion stings in the region of Campinas, southeastern Brazil.

    PubMed

    Bucaretchi, Fábio; Fernandes, Luciane C R; Fernandes, Carla B; Branco, Maíra M; Prado, Camila C; Vieira, Ronan J; De Capitani, Eduardo M; Hyslop, Stephen

    2014-10-01

    Scorpion stings account for most envenomations by venomous animals in Brazil. A retrospective study (1994-2011) of the clinical consequences of Tityus scorpion stings in 1327 patients treated at a university hospital in Campinas, southeastern Brazil, is reported. The clinical classification, based on outcome, was: dry sting (no envenoming), class I (only local manifestations), class II (systemic manifestations), class III (life-threatening manifestations, such as shock and/or cardiac failure requiring inotropic/vasopressor agents, and/or respiratory failure), and fatal. The median patient age was 27 years (interquartile interval = 15-42 years). Scorpions were brought for identification in 47.2% of cases (Tityus bahiensis 27.7%; Tityus serrulatus 19.5%). Sting severity was classified and each accounted for the following percentage of cases: dry stings - 3.4%, class I - 79.6%, class II - 15.1%, class III - 1.8% and fatal - 0.1%. Pain was the primary local manifestation (95.5%). Systemic manifestations such as vomiting, agitation, sweating, dyspnea, bradycardia, tachycardia, tachypnea, somnolence/lethargy, cutaneous paleness, hypothermia and hypotension were detected in class II or class III + fatal groups, but were significantly more frequent in the latter group. Class III and fatal cases occurred only in children <15 years old, with scorpions being identified in 13/25 cases (T. serrulatus, n = 12; T. bahiensis, n = 1). Laboratory blood abnormalities (hyperglycemia, hypokalemia, leukocytosis, elevations in serum total CK, CK-MB and troponin T, bicarbonate consumption and an increase in base deficit and blood lactate), electrocardiographic changes (ST segment) and echocardiographic alterations (ventricular ejected fraction <54%) were frequently detected in class III patients. Seventeen patients developed pulmonary edema, 16 had cardiac failure and seven had cardiogenic shock. These results indicate that most scorpion stings involved only local manifestations

  15. Potential role of frugivorous birds (Passeriformes) on seed dispersal of six plant species in a restinga habitat, southeastern Brazil.

    PubMed

    Gomes, Verônica Souza da Mota; Correia, Maria Célia Rodrigues; de Lima, Heloisa Alves; Alves, Maria Alice S

    2008-03-01

    Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation) is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1,680 net-hrs) and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis) in the present study

  16. Low-Temperature Thermochronology Applied to Constrain the Multi-Episodic Thermotectonic Evolution of the Southeastern Continental Margin of Brazil

    NASA Astrophysics Data System (ADS)

    Mendes, L. D.; Heilbron, M. C. P. L.; Hodges, K. V.; Van Soest, M. C.; Silva, L. G. A. E.

    2015-12-01

    Low-temperature thermochronology was applied to constrain the Mesozoic and Cenozoic tectonic evolution of the continental margin of southeast Brazil. Using apatite (U-Th)/He thermochronology (AHe), we acquired data from 107 crystals of basement samples collected from a NW-SE transect in the Mantiqueira Mountains to the Guanabara Graben, as well as from the NE-SE transverse faults. The data range from 43.5 ± 1.9 Ma to 250.1 ± 8.7 Ma (2 σ) for corrected ages. The Neo-Cretaceous, Eo-Cretaceous, and Paleocene are the main recorded AHe ages, in order of importance. The Eo-Cretaceous ages indicate the occurrence of older thermal events related to a pre-rifting phase (~121 Ma). The Neo-Cretaceous ages signify the importance of tectonic and magmatic events, and regional uplifting for the thermal history of the study area, including ages related to the Serra do Mar Mountains uplift (~86 Ma). Paleocene ages seem to be related to the reactivation (~65 Ma), which was responsible for the continental rifts in the southeastern Brazil. Finally, the Eocene ages (49.7 Ma and 43.5 Ma), which are from samples restricted to the Resende Basin border faults, indicate a continental rift reactivation. Time-temperature (t-T) paths obtained from inverse modeling, performed using HeFTy (Ketcham, 2005) with a Radiation Damage Diffusion and Annealing Model (Flowers et al., 2009), suggests rapid cooling episodes for all samples. The main thermal events show a direct correlation with the timing of regional tectonic events: reactivation phases, continental margin uplift, and the sedimentary record. Apatite (U-Th)/He ages increase with distance from the coast and with elevation. However, these patterns are discontinued by samples of younger ages as a result of the reactivation process of pre-existing structures. The total estimated denudation range from 1.2 to 2.8 km. The erosion rates range from 15.2 to 35.3 m/My. Thus, the multi-episodic thermal events, which led to the formation of important

  17. Hantavirus pulmonary syndrome and rodent reservoirs in the savanna-like biome of Brazil's southeastern region.

    PubMed

    Limongi, J E; Oliveira, R C; Guterres, A; Costa Neto, S F; Fernandes, J; Vicente, L H B; Coelho, M G; Ramos, V N; Ferreira, M S; Bonvicino, C R; D'Andrea, P S; Lemos, E R S

    2016-04-01

    This paper describes the diversity of rodent fauna in an area endemic for hantavirus cardiopulmonary syndrome (HCPS) in Brazil, the population dynamics and the relationship of rodents with hantavirus in the Cerrado (savanna-like) biome. Additionally, an analysis is made of the partial S segment sequences of the hantaviruses obtained from serologically confirmed human HCPS cases and from rodent specimens. Rodents were collected during four campaigns. Human serum samples were collected from suspected cases of HCPS at hospitals in the state of Minas Gerais. The samples antibody-reactive by ELISA were processed by RT-PCR. The PCR product was amplified and sequenced. Hantavirus was detected only in Necromys lasiurus, the wild rodent species most prevalent in the Cerrado biome (min-max: 50-83·7%). All the six human serum samples were hantavirus seropositive and five showed amplified PCR products. The analysis of the nucleotide sequences showed the circulation of a single genotype, the Araraquara hantavirus. The environmental changes that have occurred in the Cerrado biome in recent decades have favoured N. lasiurus in interspecific competition of habitats, thus increasing the risk of contact between humans and rodent species infected with hantavirus. Our data corroborate the definition of N. lasiurus as the main hantavirus reservoir in the Cerrado biome. PMID:26541807

  18. Spatial-temporal distribution of fire-protected savanna physiognomies in Southeastern Brazil.

    PubMed

    Pinheiro, Marcelo H O; Azevedo, Thiago S de; Monteiro, Reinaldo

    2010-06-01

    The analysis of the influence of edaphic finer textures, as a facilitating factor for the expansion of forest formations in the absence of fire, was possible thanks to rare characteristics found in a savanna fragment located in the State of São Paulo, Brazil. The total suppression of fire for over four decades, and the occurrence of two savanna physiognomies, cerrado sensu stricto and cerradão, allowed the conduction of this study based on the hypothesis that cerradão, a physiognomy of forest aspect consisting of fire-sensitive tree and shrubs species, is favored by fire absence and higher soil hydric retention capacity. Edaphic samples were collected from a regular grid of 200 m(2) for the production of isopletic maps of the distribution of clay, fine sand, coarse sand and silt edaphic textures by the geostatistic method of ordinary kriging. Changes in the areas occupied by both savanna physiognomies, defined on the basis of aerial photographs taken over a period of 43 years, were assessed through mean variation rates. Besides corroborating the hypothesis of edaphic hydric retention as a facilitating factor for the expansion of forest physiognomies in savanna areas, we were able to infer the positive influence of higher precipitation on the increase in cerradão expansion rates. PMID:20563419

  19. Insights into Holocene megafauna survival and extinction in southeastern Brazil from new AMS 14C dates

    NASA Astrophysics Data System (ADS)

    Hubbe, Alex; Hubbe, Mark; Karmann, Ivo; Cruz, Francisco W.; Neves, Walter A.

    2013-03-01

    The extinction of late Quaternary megafauna in South America has been extensively debated in past decades. The majority of the hypotheses explaining this phenomenon argue that the extinction was the result of human activities, environmental changes, or even synergism between the two. Although still limited, a good chronological framework is imperative to discuss the plausibility of the available hypotheses. Here we present six new direct AMS 14C radiocarbon dates from the state of São Paulo (Brazil) to further characterize the chronological distribution of extinct fauna in this part of South America. The new dates make evident that ground sloths, toxodonts, and saber-toothed cats lived in the region around the Pleistocene/Holocene transition, and, in agreement with previous studies, also suggest an early Holocene survival for the ground sloth Catonyx cuvieri. Taken together with local paleoclimatic and archaeological data, the new dates do not support hunting or indirect human activities as a major cause for megafauna extinction. Although more data are required, parsimony suggests that climatic changes played a major role in this extinction event.

  20. DENTAL CARIES EXPERIENCE IN 12-YEAR-OLD SCHOOLCHILDREN IN SOUTHEASTERN BRAZIL

    PubMed Central

    Cypriano, Silvia; Hoffmann, Rosana H. S.; de Sousa, Maria da Luz R.; Wada, Ronaldo S.

    2008-01-01

    The aim of this study was to evaluate the prevalence of caries-free children using DMFT and significant caries (SiC) indexes in different caries prevalence groups in cities of the region of Campinas, São Paulo State, Brazil. The methodology proposed by the World Health Organization (1997) was used for caries diagnosis in 2,378 individuals. According to the DMFT index obtained in each evaluated city, 3 prevalence groups with representative samples were formed, being classified as low, moderate and high. SiC index was used to classify the one third of the population with the highest caries prevalence. In the low prevalence group, 32.4% of the children were caries free (DMFT=0), with mean DMFT of 2.29 and SiC index of 4.93. In the moderate prevalence group, 21.8% of the children were caries free, with mean DMFT of 3.36 and SiC of 6.74. Only 6.9% of the children in the high prevalence group were caries free and the mean DMFT was 5.54 (SiC=9.62). There was a great heterogeneity in dental caries distribution within the studied population, as well as a high caries prevalence considering the 3 classifications. Other indexes besides DMFT could be used to improve oral health assessment during establishment of the treatment plan and intervention. PMID:19089262

  1. Sphincterodiplostomum musculosum (Digenea, Diplostomidae) infecting Steindachnerina insculpta (Characiformes, Curimatidae) in the Chavantes Reservoir, Southeastern Brazil.

    PubMed

    Zago, Aline Cristina; Franceschini, Lidiane; Ramos, Igor Paiva; Zica, Erica de Oliveira Penha; Wunderlich, Alison Carlos; Carvalho, Edmir Daniel; Silva, Reinaldo José da

    2013-01-01

    This study aimed to report the infection by Sphincterodiplostomum musculosum metacercariae in Steindachnerina insculpta from the Chavantes Reservoir, medium Paranapanema River, municipality of Ipaussu, State of São Paulo, Brazil. Thirty specimens of S. insculpta were collected and 29 were infected with S. musculosum metacercariae (prevalence = 96.67%) in the eyes and visceral cavity. The mean intensity of infection and abundance were 96.6 ± 29.41 (7-846) and 93.3 ± 28.6 (0-846), respectively. Positive correlation was observed between parasite abundance in the eyes and standard length (rs = 0.5, p = 0.005), total weight (rs = 0.649, p = 0.0001), and condition factor (rs = 0.439, p = 0.0154). The high parasitism rates by S. musculosum metacercariae in S. insculpta can be an indicative that this fish species is highly susceptible to infection by this diplostomid, and even reflect the presence of a large abundance of the intermediate host. Moreover, S. musculosum metacercariae are reported for the first time in S. insculpta. PMID:24252954

  2. Survey for Tick-Borne Zoonoses in the State of Espirito Santo, Southeastern Brazil

    PubMed Central

    Spolidorio, Mariana G.; Labruna, Marcelo B.; Machado, Rosangela Z.; Moraes-Filho, Jonas; Zago, Augusto M.; Donatele, Dirlei M.; Pinheiro, Sônia R.; Silveira, Iara; Caliari, Késia M.; Yoshinari, Natalino H.

    2010-01-01

    Blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of Espirito Santo, Brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). Our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were reactive to at least one of the six Rickettsia species tested. Although there was evidence of ehrlichiosis (Ehrlichia canis) and babesiosis (Babesia canis vogeli, Theileria equi) in domestic animals, no human was positive for babesiosis and only four individuals were serologically positive for E. canis. Borrelia burgdorferi-serologic reactive sera were rare among humans and horses, but encompassed 51% of the canine samples, suggesting that dogs and their ticks can be part of the epidemiological cycle of the causative agent of the Brazilian zoonosis, named Baggio-Yoshinari Syndrome. PMID:20595502

  3. Larvacean (Chordata, Tunicata) abundance and inferred secondary production off southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Miyashita, Leonardo K.; Lopes, Rubens M.

    2011-05-01

    We studied the temporal and vertical variability in larvacean abundance and secondary production on a fixed station off southeast Brazil, from January 2007 to December 2008. Larvacean biomass was derived from length-weight regressions, and growth rates were estimated from an empirical model. We identified eleven larvacean species. Oikopleura longicauda occurred throughout the studied period and was the most abundant species, followed by Oikopleura fusiformis. Fritillaria haplostoma, O. fusiformis and O. longicauda were found mainly above the thermocline, whereas Oikopleura dioica and Fritillaria pellucida preferred bottom layers. Higher abundance and biomass were observed in warmer months, when the water column was stratified as a result of the bottom intrusions of the cold and nutrient-rich South Atlantic Central Water. Secondary production mirrored the biomass seasonal pattern. Larvacean biomass equaled to less than 10% of copepod biomass during the same period, but larvacean production comprised on average 77% that of copepods, whereas the production of discarded houses and fecal pellets comprised up to 2800% of larvaceans secondary production. This confirms the potential significance of larvaceans in the carbon flux in tropical and subtropical coastal regions.

  4. Radioactivity and gamma-dose rates observed at the Morungaba granites, Southeastern Brazil.

    PubMed

    Lucas, Fabio de Oliveira; Ribeiro, Fernando Brenha

    2013-07-01

    A ground gamma-ray survey was conducted over part of a large granitic body located near the city of Campinas, eastern São Paulo State, Brazil. The dominant rock types are K-feldspar porphyries-rich granites, porphyritic biotite and hornblend-bearing granites, fine to medium-grained monzogranites and medium to gross grained, biotite and muscovite-bearing monzogranites. The radioactive element distribution reflects local geology, in part re-worked by weathering, and the most radioactive rocks are the K-feldspar-rich granites. The rate of the absorbed dose by the air reflects the integrated effects of the radioactive elements distribution. Most of the observed values vary between 67 and 130 nGy h(-1) and with localised spots with the absorbed dose rate values up to 193 nGy h(-1) and low values of ∼25 nGy h(-1). The mean air absorbed dose rate for the studied area is 77 nGy h(-1). PMID:23222823

  5. Ryegrass cv. Lema and guava cv. Paluma biomonitoring suitability for estimating nutritional contamination risks under seasonal climate in Southeastern Brazil.

    PubMed

    Bulbovas, Patricia; Camargo, Carla Z S; Domingos, Marisa

    2015-08-01

    The risks posed by nutrient deposition due to air pollution on ecosystems and their respective services to human beings can be appropriately estimated by bioindicator plants when they are well acclimated to the study region environmental conditions. This assumption encouraged us to comparatively evaluate the accumulation potential of ryegrass cv. Lema and guava cv. Paluma macro and micronutrients. We also indicated the most appropriate species for biomonitoring nutrient contamination risks in tropical areas of Southeastern Brazil, which are characterized by marked dry and wet seasons and complex mixtures of air pollutants from different sources (industries, vehicle traffic and agriculture). The study was conducted in 14 sites with different neighboring land uses, within the Metropolitan Region of Campinas, central-eastern region of São Paulo State. The exposure experiments with ryegrass and guava were consecutively repeated 40 (28 days each) and 12 (84 days each) times, respectively, from Oct/2010 to Sept/2013. Macro and micronutrients were analyzed and background concentrations and enrichment ratios (ER) were estimated to classify the contamination risk within the study region. Significantly higher ER suggested that ryegrass were the most appropriate accumulator species for N, S, Mg, Fe, Mn, Cu and Zn deposition and guava for K, Ca, P and B deposition. Based on these biomonitoring adjustments, we concluded that the nutrient deposition was spatially homogeneous in the study area, but clear seasonality in the contamination risk by nutritional inputs was evidenced. Significantly higher contamination risk by S, Fe, K and B occurred during the dry season and enhanced contamination risk by Mn, Cu and Zn were highlighted during the wet season. Distinctly high contamination risk was estimated for S, Fe and Mn in several exposure experiments. PMID:25938695

  6. Colonization by Chironomidae Larvae in Decomposition Leaves of Eichhornia azurea in a Lentic System in Southeastern Brazil

    PubMed Central

    da Silveira, Lidimara Souza; Martins, Renato Tavares; da Silveira, Guilherme Augusto; Grazul, Richard Michael; Lobo, Danielle Pinheiro; da Gama Alves, Roberto

    2013-01-01

    The objective of this study was to analyze the colonization of Chironomidae (Diptera) larvae during the decomposition of Eichhornia azurea (Swartz) Kunth (Commelinales: Pontederiaceae) leaves in a lake in southeastern Brazil in two seasons of the year. The experiment was conducted from September to November 2007 and February to April 2008. In each period, 21 litter bags were used, each containing 10 g of dried leaves. Three bags were removed after 2, 5, 8, 12, 25, 45, and 65 days of colonization. The decomposition rate of the E. azurea leaves was rapid in both seasons, with no significant difference between them. The Chironomidae showed higher density than the other invertebrates. Goeldichironomus, Tonytarsus, and Corynoneura were the most abundant genera of Chironomidae. The invertebrate density increased during the experiment, differing within days but not between seasons. The faunal composition differed between the decomposition phases (initial and final), but did not differ between the seasons (dry and wet). The taxa Ablabesmyia, Caladomyia, Chironomus, Goeldichironomus, and Parachironomus were the most closely related to the final days of the experiment. Litter was the main food item found in the gut contents of the organisms of all the genera analyzed, both at the beginning and end of the decomposition. We believe that the feeding activity combined with the high larval density is an important factor contributing to the rapid decomposition of the E. azurea leaves. In conclusion, the succession process along the detritus chain of E. azurea was more important in structuring the assemblage of Chironomidae larvae than seasonal variations. PMID:23886040

  7. THE DRAINAGE EFFICIENCY INDEX (DEI) AS AN MORPHOLOGIAL INDICATOR OF LANDSLIDE SPATIAL OCCURRENCE IN MOUNTAINOUS CATCHMENTS. A case of study applied in the mountainous region of Brazilian Southeastern.

    NASA Astrophysics Data System (ADS)

    Henrique Muniz Lima, Pedro; Luiza Coelho Netto, Ana; do Couto Fernandes, Manoel

    2016-04-01

    Morphometric parameters, acquired notoriety mainly after the Drainage Density proposition (Horton 1932, 1945) and after they were applied by geomorphologists on the perspective to understand landscape functionalities, quantifying their characteristics through parameters and indexes. After the drainage density, many other parameters which describe the basin characteristics, behavior and dynamics have been proposed. Among them, for example, the DEI was proposed by Coelho Netto and contributors during the 80's, while they were seek to understand the hydrological and erosive dynamics on Bananal river basin (Brazilian Southeastern). Through this investigations the DEI was created, revealing the importance of parameters as hollow and drainage density, conjugated to the topographic gradient (Meis et al. 1982) who prosecute controls on the water flow efficiency along the hollows in order to activate the regressive erosion of the main channel. Later on this index was applied on the basin scale in several works developed in mountainous regions, showing a remarkable correlation with the occurrence of landslides such as showed by Coelho Netto et al. (2007); that posteriorly use this index as one of the components of the landslide susceptibility map for the Tijuca Massif, located in Rio de Janeiro Municipality. This work aims to establish patterns of the DEI index values (applied to mountainous low order basins) and the relationship on the occurrence of Debriflows or shallow translational slides. For this, the DEI index was applied on 4 different study areas located on the Southeastern mountainous region of Brazil to address deeply the connection between the index and the occurrence of landslides of different types applied for first and second order basins. The major study area is the Córrego Dantas Basin, situated in Nova Friburgo municipality (RJ), which is a 53 km² basin was affected by 327 landslides caused by a heavy rainfall on January 2011; Coelho Netto et al. (in

  8. ENTEROPATHOGENS DETECTED IN A DAYCARE CENTER, SOUTHEASTERN BRAZIL: BACTERIA, VIRUS, AND PARASITE RESEARCH

    PubMed Central

    Castro, Edna Donizetti Rossi; Germini, Marcela Cristina Braga Yassaka; Mascarenhas, Joana D'Arc Pereira; Gabbay, Yvone Benchimol; de Lima, Ian Carlos Gomes; Lobo, Patrícia dos Santos; Fraga, Valéria Daltibari; Conceição, Luciana Moran; Machado, Ricardo Luiz Dantas; Rossit, Andréa Regina Baptista

    2015-01-01

    Introduction: The objective of this study was to determine the prevalence and etiological profile of enteropathogens in children from a daycare center. Methods: From October 2010 to February 2011 stool samples from 100 children enrolled in a government daycare center in the municipality of São José do Rio Preto, in the state of São Paulo, were collected and analyzed. Results: A total of 246 bacteria were isolated in 99% of the fecal samples; 129 were in the diarrheal group and 117 in the non-diarrheal group. Seventy-three strains of Escherichia coli were isolated, 19 of Enterobacter, one of Alcaligenes and one of Proteus. There were 14 cases of mixed colonization with Enterobacter and E. coli. Norovirus and Astrovirus were detected in children with clinical signs suggestive of diarrhea. These viruses were detected exclusively among children residing in urban areas. All fecal samples were negative for the presence of the rotavirus species A and C. The presence of Giardia lamblia, Entamoeba coli, Endolimax nana and hookworm was observed. A significant association was found between food consumption outside home and daycare center and the presence of intestinal parasites. Conclusions: For children of this daycare center, intestinal infection due to pathogens does not seem to have contributed to the occurrence of diarrhea or other intestinal symptoms. The observed differences may be due to the wide diversity of geographical, social and economic characteristics and the climate of Brazil, all of which have been reported as critical factors in the modulation of the frequency of different enteropathogens. PMID:25651323

  9. Landslide susceptibility mapping using a bivariate statistical model in a tropical hilly area of southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Araújo, J. P. C.; DA Silva, L. M.; Dourado, F. A. D.; Fernandes, N.

    2015-12-01

    Landslides are the most damaging natural hazard in the mountainous region of Rio de Janeiro State in Brazil, responsible for thousands of deaths and important financial and environmental losses. However, this region has currently few landslide susceptibility maps implemented on an adequate scale. Identification of landslide susceptibility areas is fundamental in successful land use planning and management practices to reduce risk. This paper applied the Bayes' theorem based on weight of evidence (WoE) using 8 landslide-related factors in a geographic information system (GIS) for landslide susceptibility mapping. 378 landslide locations were identified and mapped on a selected basin in the city of Nova Friburgo, triggered by the January 2011 rainfall event. The landslide scars were divided into two subsets: training and validation subsets. The 8 landslide-related factors weighted by WoE were performed using chi-square test to indicate which variables are conditionally independent of each other to be used in the final map. Finally, the maps of weighted factors were summed up to construct the landslide susceptibility map and validated by the validation landslide subset. According to the results, slope, aspect and contribution area showed the higher positive spatial correlation with landslides. In the landslide susceptibility map, 21% of the area presented very low and low susceptibilities with 3% of the validation scars, 41% presented medium susceptibility with 22% of the validation scars and 38% presented high and very high susceptibilities with 75% of the validation scars. The very high susceptibility class stands for 16% of the basin area and has 54% of the all scars. The approach used in this study can be considered very useful since 75% of the area affected by landslides was included in the high and very high susceptibility classes.

  10. Land-use and environmental changes in the Cerrados of South-Eastern Mato Grosso -- Brazil

    NASA Astrophysics Data System (ADS)

    Grecchi, Rosana Cristina

    The human-induced changes of the Earth's land surfaces have been unprecedented, with outcomes often indicating degradation and loss of environmental quality. Mato Grosso State in Brazil, location of the study area, underwent extensive land-use and land-cover changes in recent decades with the rates, patterns and consequences poorly documented until now. In this context, the aim of the present research is to propose a multidisciplinary approach for quantifying historical land-use and environmental changes in the southeast part of this State, where the Cerrado biome (Brazilian savannas) has been intensively converted into agricultural lands. The methodology includes three parts: remote sensing change detection, land vulnerability mapping, and identification of key environmental indicators. Land-use/cover information was extracted from a temporal remote sensing dataset using an object-oriented classification approach, and the changes quantified employing a post-classification method. In addition, the study area was assessed for its vulnerabilities, focusing mainly on erosion risks, wetlands, and areas with limited or no suitability for crops. Finally, key environmental indicators were identified from the preceding steps and analyzed within the Organisation for Economic Co-operation and Development (OECD) Pressure-State-Response (PSR) framework. The results provided an improved mapping of the Cerrados natural vegetation conversion into crops and pastures, and indicate that the Cerrado vegetation was intensively converted and also became more fragmented in the time frame studied. Between 1985 and 2005 the area lost approximately 6491 km 2 of Cerrados (42 %). Modeling based on the Universal Soil Loss Equation indicated significant increase in erosion risk from 1985 to 2005 mainly related to the increase in crop areas and the crops' encroachment into more fragile lands. The identification of environmental indicators rendered complex environmental information more

  11. Fault valve action and vein development during strike slip faulting: An example from the Ribeira Shear Zone, Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Faleiros, Frederico Meira; Campanha, Ginaldo Ademar da Cruz; Bello, Rosa Maria da Silveira; Fuzikawa, Kazuo

    2007-06-01

    Fluid inclusion microthermometry and structural data are presented for quartz vein systems of a major dextral transcurrent shear zone of Neoproterozoic-Cambrian age in the Ribeira River Valley area, southeastern Brazil. Geometric and microstructural constraints indicate that foliation-parallel and extensional veins were formed during dextral strike-slip faulting. Both vein systems are formed essentially by quartz and lesser contents of sulfides and carbonates, and were crystallized in the presence of CO 2-CH 4 and H 2O-CO 2-CH 4-NaCl immiscible fluids following unmixing from a homogeneous parental fluid. Contrasting fluid entrapment conditions indicate that the two vein systems were formed in different structural levels. Foliation-parallel veins were precipitated beneath the seismogenic zone under pressure fluctuating from moderately sublithostatic to moderately subhydrostatic values (319-397 °C and 47-215 MPa), which is compatible with predicted fluid pressure cycle curves derived from fault-valve action. Growth of extensional veins occurred in shallower structural levels, under pressure fluctuating from near hydrostatic to moderately subhydrostatic values (207-218 °C and 18-74 MPa), which indicate that precipitation occurred within the near surface hydrostatically pressured seismogenic zone. Fluid immiscibility and precipitation of quartz in foliation-parallel veins resulted from fluid pressure drop immediately after earthquake rupture. Fluid immiscibility following a local pressure drop during extensional veining occurred in pre-seismic stages in response to the development of fracture porosity in the dilatant zone. Late stages of fluid circulation within the fault zone are represented dominantly by low to high salinity (0.2 to 44 wt.% equivalent NaCl) H 2O-NaCl-CaCl 2 fluid inclusions trapped in healed fractures mainly in foliation-parallel veins, which also exhibit subordinate H 2O-NaCl-CaCl 2, CO 2-(CH 4) and H 2O-CO 2-(CH 4)-NaCl fluid inclusions trapped

  12. Adequacy assessment of mathematical models in the dynamics of litter decomposition in a tropical forest Mosaic Atlantic, in southeastern Brazil.

    PubMed

    Nunes, F P; Garcia, Q S

    2015-05-01

    The study of litter decomposition and nutrient cycling is essential to know native forests structure and functioning. Mathematical models can help to understand the local and temporal litter fall variations and their environmental variables relationships. The objective of this study was test the adequacy of mathematical models for leaf litter decomposition in the Atlantic Forest in southeastern Brazil. We study four native forest sites in Parque Estadual do Rio Doce, a Biosphere Reserve of the Atlantic, which were installed 200 bags of litter decomposing with 20 × 20 cm nylon screen of 2 mm, with 10 grams of litter. Monthly from 09/2007 to 04/2009, 10 litterbags were removed for determination of the mass loss. We compared 3 nonlinear models: 1 - Olson Exponential Model (1963), which considers the constant K, 2 - Model proposed by Fountain and Schowalter (2004), 3 - Model proposed by Coelho and Borges (2005), which considers the variable K through QMR, SQR, SQTC, DMA and Test F. The Fountain and Schowalter (2004) model was inappropriate for this study by overestimating decomposition rate. The decay curve analysis showed that the model with the variable K was more appropriate, although the values of QMR and DMA revealed no significant difference (p > 0.05) between the models. The analysis showed a better adjustment of DMA using K variable, reinforced by the values of the adjustment coefficient (R2). However, convergence problems were observed in this model for estimate study areas outliers, which did not occur with K constant model. This problem can be related to the non-linear fit of mass/time values to K variable generated. The model with K constant shown to be adequate to describe curve decomposition for separately areas and best adjustability without convergence problems. The results demonstrated the adequacy of Olson model to estimate tropical forest litter decomposition. Although use of reduced number of parameters equaling the steps of the decomposition

  13. An observed database to characterize the weather conditions associated with subtropical cyclogenesis over southern-southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Yamamoto, R.; Porfirio da Rocha, R.

    2012-04-01

    A project to study the climatic, dynamic and synoptic aspects of subtropical cyclones that develop in southern-southeastern coast of Brazil is in development. The weather conditions associated with such cyclones is an important question that must be answered in this project. However, for such characterization it is necessary to use the local meteorological observations of wind, wind gust, rainfall, air temperature, etc. The NCEP (National Center for Environmental Prediction) reanalysis have spatial and time resolutions that provide elements to study the synoptic and dynamics of meteorological events (cyclone, anticyclones, troughs, ridges, monsoons circulations, etc) until the production of complex climatology. However, this analysis has coarse horizontal resolution (~250 Km) that often does not allow the identification of intense meteorological phenomena. A more precise characterization of location and intensity of weather conditions associated with subtropical cyclones would be performed using local observations. Therefore, this work describes the methodology to construct a database of surface weather observations using a relational database management system (RDBMS) MySQL. The data source are SYNOP (Surface Synoptic Observations), METAR (Meteorological Aerodrome Report), NCDC (National Climatic Data Center) and CETESB (Environmental Agency of Sao Paulo State) that are available online through dynamic web page. An iterative algorithm robot was developed to automate the data extraction. Most of the data source are encoded or at non-standard format, hence was developed an algorithm in C++, using the REGEX library, an engine of text pattern search, for decode and handle the exception (erroneous and corrupted data). After the data decoding and formatting it is stored into the MySQL database. The structure of database was divided into categories of tables: a table with the source of data definition, a table with stations information and two sets of tables (for hourly

  14. Alternative method to trace sediment sources in a subtropical rural catchment of southern Brazil by using near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Tiecher, Tales; Caner, Laurent; Gomes Minella, Jean Paolo; Henrique Ciotti, Lucas; Antônio Bender, Marcos; dos Santos Rheinheimer, Danilo

    2014-05-01

    Conventional fingerprinting methods based on geochemical composition still require a time-consuming and critical preliminary sample preparation. Thus, fingerprinting characteristics that can be measured in a rapid and cheap way requiring a minimal sample preparation, such as spectroscopy methods, should be used. The present study aimed to evaluate the sediment sources contribution in a rural catchment by using conventional method based on geochemical composition and on an alternative method based on near-infrared spectroscopy. This study was carried out in a rural catchment with an area of 1,19 km2 located in southern Brazil. The sediment sources evaluated were crop fields (n=20), unpaved roads (n=10) and stream channels (n=10). Thirty suspended sediment samples were collected from eight significant storm runoff events between 2009 and 2011. Sources and sediment samples were dried at 50oC and sieved at 63 µm. The total concentration of Ag, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sr, Ti, Tl, V and Zn were estimated by ICP-OES after microwave assisted digestion with concentrated HNO3 and HCl. Total organic carbon (TOC) was estimated by wet oxidation with K2Cr2O7 and H2SO4. The near-infrared spectra scan range was 4000 to 10000 cm-1 at a resolution of 2 cm-1, with 100 co added scans per spectrum. The steps used in the conventional method were: i) tracer selection based on Kruskal-Wallis test, ii) selection of the best set of tracers using discriminant analyses and finally iii) the use of a mixed linear model to calculate the sediment sources contribution. The steps used in the alternative method were i) principal component analyses to reduce the number of variables, ii) discriminant analyses to determine the tracer potential of the near-infrared spectroscopy, and finally iii) the use of past least square based on 48 mixtures of the sediment sources in various weight proportions to calculate the sediment sources

  15. EMISSION OF OZONE IN THE VALE DO PARAÍBA REGION, IN SOUTHEASTERN BRAZIL, FOR THE YEAR 2007

    NASA Astrophysics Data System (ADS)

    Dos Santos Zepka, A.; Sales, A. B.; Alvalá, P. C.

    2009-12-01

    The city of São José dos Campos (São Paulo, Brazil) in recent years has shown strong growth and current increase in industrial economy, leading to a sharp urban development and consequent problems of air pollution. The ozone is a major greenhouse gas, present in the troposphere by photochemical reactions in natural emissions of anthropogenic and biogenic hydrocarbons such as volatile organic compounds and nitrogen oxides, which can come from lightning and soil. Due to the fact that this gas is considered the main pollutant responsible for poor air quality, the objective of this study was to characterize the behavior of the emission of ozone in the Vale do Paraíba region, in Southeastern Brazil, in association with meteorological parameters. Researches in this area are essential, because of the need for better knowledge on air quality at regional and global. The motivation for this study was based on the fact that the ozone near the surface can be considered a gas harmful to human and animal health, crops and forests as well of urban areas in general, besides being used as a major indicators of air quality by agencies of monitoring environment, such as the IPCC (Intergovernmental Panel on Climate Change), for example. This study is an initial analysis that will lead to a better understanding of chemical and physical processes that occur in the atmosphere of the city and region. Ozone and meteorological data were obtained from two locations in the city, known as INPE (23°12,04'S; 45°51,06'W) and UNIVAP (23°12,05'S; 45°57,02'W) during the year 2007. The ozone data were obtained every 15 minutes and converted in hourly and daily averages. In addition, were collected the maximum and minimum measure daily. The ozone showed similar behavior to temperature and irradiance for the period studied. In spring and summer there was an increase of ozone mixing ratio, which was produced photochemically during the increase of solar irradiance. Moreover, the periods of autumn

  16. Anthropogenic landscape in southeastern Amazonia: contemporary impacts of low-intensity harvesting and dispersal of Brazil nuts by the Kayapó Indigenous people.

    PubMed

    Ribeiro, Maria Beatriz N; Jerozolimski, Adriano; de Robert, Pascale; Salles, Nilson V; Kayapó, Biribiri; Pimentel, Tania P; Magnusson, William E

    2014-01-01

    Brazil nut, the Bertholletia excelsa seed, is one of the most important non-timber forest products in the Amazon Forest and the livelihoods of thousands of traditional Amazonian families depend on its commercialization. B. excelsa has been frequently cited as an indicator of anthropogenic forests and there is strong evidence that past human management has significantly contributed to its present distribution across the Amazon, suggesting that low levels of harvesting may play a positive role in B. excelsa recruitment. Here, we evaluate the effects of Brazil nut harvesting by the Kayapó Indigenous people of southeastern Amazonia on seedling recruitment in 20 B. excelsa groves subjected to different harvesting intensities, and investigated if management by harvesters influences patterns of B. excelsa distribution. The number of years of low-intensity Brazil nut harvesting by the Kayapó over the past two decades was positively related to B. excelsa seedling density in groves. One of the mechanisms behind the higher seedling density in harvested sites seems to be seed dispersal by harvesters along trails. The Kayapó also intentionally plant B. excelsa seeds and seedlings across their territories. Our results show not only that low-intensity Brazil nut harvesting by the Kayapó people does not reduce recruitment of seedlings, but that harvesting and/or associated activities conducted by traditional harvesters may benefit B. excelsa beyond grove borders. Our study supports the hypothesis that B. excelsa dispersal throughout the Amazon was, at least in part, influenced by indigenous groups, and strongly suggests that current human management contributes to the maintenance and formation of B. excelsa groves. We suggest that changes in Brazil nut management practices by traditional people to prevent harvesting impacts may be unnecessary and even counterproductive in many areas, and should be carefully evaluated before implementation. PMID:25029191

  17. Anthropogenic Landscape in Southeastern Amazonia: Contemporary Impacts of Low-Intensity Harvesting and Dispersal of Brazil Nuts by the Kayapó Indigenous People

    PubMed Central

    Ribeiro, Maria Beatriz N.; Jerozolimski, Adriano; de Robert, Pascale; Salles, Nilson V.; Kayapó, Biribiri; Pimentel, Tania P.; Magnusson, William E.

    2014-01-01

    Brazil nut, the Bertholletia excelsa seed, is one of the most important non-timber forest products in the Amazon Forest and the livelihoods of thousands of traditional Amazonian families depend on its commercialization. B. excelsa has been frequently cited as an indicator of anthropogenic forests and there is strong evidence that past human management has significantly contributed to its present distribution across the Amazon, suggesting that low levels of harvesting may play a positive role in B. excelsa recruitment. Here, we evaluate the effects of Brazil nut harvesting by the Kayapó Indigenous people of southeastern Amazonia on seedling recruitment in 20 B. excelsa groves subjected to different harvesting intensities, and investigated if management by harvesters influences patterns of B. excelsa distribution. The number of years of low-intensity Brazil nut harvesting by the Kayapó over the past two decades was positively related to B. excelsa seedling density in groves. One of the mechanisms behind the higher seedling density in harvested sites seems to be seed dispersal by harvesters along trails. The Kayapó also intentionally plant B. excelsa seeds and seedlings across their territories. Our results show not only that low-intensity Brazil nut harvesting by the Kayapó people does not reduce recruitment of seedlings, but that harvesting and/or associated activities conducted by traditional harvesters may benefit B. excelsa beyond grove borders. Our study supports the hypothesis that B. excelsa dispersal throughout the Amazon was, at least in part, influenced by indigenous groups, and strongly suggests that current human management contributes to the maintenance and formation of B. excelsa groves. We suggest that changes in Brazil nut management practices by traditional people to prevent harvesting impacts may be unnecessary and even counterproductive in many areas, and should be carefully evaluated before implementation. PMID:25029191

  18. A new and possibly critically endangered species of casque-headed tree frog Aparasphenodon Miranda-Ribeiro, 1920 (Anura, Hylidae) from southeastern Brazil.

    PubMed

    De Assis, Clodoaldo Lopes; Santana, Diego José; Da Silva, Fabiano Aguiar; Quintela, Fernando Marques; Feio, Renato Neves

    2013-01-01

    A new species of casque-headed tree frog of the genus Aparasphenodon is described from the municipality of Cataguases (21°20'S, 42°45'W; 288 m a.s.l.) in the Atlantic Rain Forest of Minas Gerais State, southeastern Brazil. Aparasphenodon pomba sp. nov. is characterized by medium size (males, snout-vent length, SVL 51.6-60.5 mm; females, SVL 58.7-62.1 mm); snout almost round in dorsal view; dorsum and limbs with cream-colored reticulation on dark-brown background; spots on ventral surface cream-colored; lips white; cream-colored dorsolateral stripe originating on the snout, crossing the upper eyelid and extending posteriorly to the axilla level; and red iris. PMID:26106793

  19. Radioactivity distribution in some Permian sediments from the Iratí and Corumbataí Formations of the Paraná Basin, Southeastern Brazil.

    PubMed

    Carlos, Dionísio Uendro; Ribeiro, Fernando Brenha; Saad, Antonio Roberto; Nicolai, Silvia Helena de Araújo

    2004-01-01

    In the city of Limeira, southeastern Brazil, an important exposure of Permian sediments of the Paraná basin was revealed by an open pit mine that exploits limestone for production of soil correction compounds and raw materials for the ceramic industry. The radioactivity of these sediments was investigated in some detail and the results provided a general view of the vertical distributions of uranium, thorium and potassium concentrations and of the element ratios U/K, U/Th and Th/K. In general, the concentrations of the main natural radioactive elements are low, with uranium being enriched in some limestone and shale levels. In addition the results showed that the 238U series is in radioactive disequilibrium in many of the analyzed samples. Although the origin of the observed disequilibrium has not been investigated, the results suggest that it is due to weathering processes and water interaction with the rock matrix. PMID:14687638

  20. Long-term background denudation rates of southern and southeastern Brazilian watersheds estimated with cosmogenic 10Be

    NASA Astrophysics Data System (ADS)

    Sosa Gonzalez, Veronica; Bierman, Paul R.; Fernandes, Nelson F.; Rood, Dylan H.

    2016-09-01

    mean basin slope (R2 = 0.33) and weakly but significantly to mean annual precipitation (R2 = 0.05). These relationships are weaker when considering all southern and southeastern Brazil samples than they are in our smaller, localized data set. We find that smaller, steeper headwater catchments (many on escarpments) erode faster than the larger, higher-order but lower slope catchments. Erosion in southern and southeastern Brazil appears to be controlled largely by mean basin slope with lesser influence by climate and lithology.

  1. Initial Abstraction and Curve Numbers in a Semiarid Watershed in Southeastern Arizona

    EPA Science Inventory

    The Soil Conservation Service curve number estimates of direct runoff from rainfall for semiarid catchments can be inaccurate. Investigation of the Walnut Gulch Experimental Watershed (Southeastern Arizona) and its 10 nested catchments determined that the inaccuracy is due to an ...

  2. Source-to-sink sediment transfers, environmental engineering and hazard mitigation in the steep Var River catchment, French Riviera, southeastern France

    NASA Astrophysics Data System (ADS)

    Anthony, Edward J.; Julian, Maurice

    1999-12-01

    Steep coastal margins are potentially subject to mass wasting processes involving notable landslide activity and sediment evacuation downstream by steep-gradient streams. Sediment transfer from short source-to-sink segments, coupled with mountain hydrological regimes, regulate patterns of river channel aggradation and coastal sediment supply in such geomorphic settings. On the steep French Riviera margin, sediment transfers from existing landslides or from various minor mass wasting processes to stream channels may result following bursts of heavy, concentrated rainfall. High-magnitude flooding and massive sediment transport downstream are generally related to unpredictable extreme rainfalls. Both mass movements and channel sediment storage pose serious hazards to downvalley settlements and infrastructure. A consideration of channel sediment storage patterns in the Var River catchment, the most important catchment in this area, highlights two important shortcomings relative to environmental engineering and hazard mitigation practices. In the first place, the appreciation of geomorphic processes is rather poor. This is illustrated by the undersized nature of engineering works constructed to mitigate hazards in the upstream bedload-dominated channels, and by the unforeseen effects that ten rock dams, constructed in the early 1970s, have had on downstream and coastal sediment storage and on sediment dispersal patterns and, consequently, valley flooding. Secondly, planners and environmental engineers have lacked foresight in valley and coastal management issues on this steep setting, notably as regards the reclaimed areas of the lower Var channel and delta liable to flooding. Urbanization and transport and environmental engineering works have progressively affected patterns of storage and transport of fine-grained sediments in the lower Var channel and delta. Meanwhile the problems raised by these changes have not been adequately addressed in terms of scientific

  3. Apedunculata discoidea gen. n., sp. n. (Monogenea: Dactylogyridae) parasitic on Prochilodus lineatus (Valenciennes, 1837) (Characiformes: Prochilodontidae) from southeastern Brazil.

    PubMed

    Cuglianna, A M; Cordeiro, N S; Luque, J L

    2009-08-01

    A new species of dactylogyrid monogenean, Apedunculata discoidea gen. n., sp. n. is described and illustrated from the gills of the freshwater fish Prochilodus lineatus (Valenciennes, 1837) in pisciculture ponds from Pirassununga, São Paulo, Brazil. Diagnostic characters of the new genus and species are: 1) vagina dextrolateral slightly sclerotised, opening anteriorly at level of copulatory complex; 2) copulatory organ coiled with two counterclockwise rings; 3) Accessory piece distal and not articulated; 4) body disk-shaped, lacking a peduncle. PMID:19802450

  4. Environmental availability of potentially toxic elements in estuarine sediments of the Cananéia-Iguape coastal system, Southeastern Brazil.

    PubMed

    Tramonte, Keila Modesto; Figueira, Rubens Cesar Lopes; de Lima Ferreira, Paulo Alves; Ribeiro, Andreza Portella; Batista, Miriam Fernanda; de Mahiques, Michel Michaelovitch

    2016-02-15

    The Cananéia-Iguape system is located in a Southeastern Brazilian coastal region, acknowledged by UNESCO as Biosphere Reserve of the Atlantic Rainforest. This system underwent important environmental changes due to the opening of the artificial channel of Valo Grande and by past intensive Pb ore mining activities. In view of this scenario, this study evaluated Cu, Pb and Zn availability in sediments from Cananéia-Iguape system, based on the content associated with the main components of the sediments. Moreover, in order to assess local contamination, the metals' contents were compared to Canadian quality guidelines, the past levels of metals preceding the mining activities and background sediment values. Concerning Cu and Zn in a state of chemical remobilization, both elements would possibly present no harm to the local communities. However, Pb available content exceeded the comparison values in various sampling sites, suggesting the need of monitoring regarding its bioavailability. PMID:26707887

  5. New geological and single-zircon Pb evaporation data from the Central Guyana Domain, southeastern Roraima, Brazil: Tectonic implications for the central region of the Guyana Shield

    NASA Astrophysics Data System (ADS)

    Almeida, Marcelo E.; Macambira, Moacir J. B.; Valente, Sérgio de C.

    2008-11-01

    Metagranitoid rocks, mylonites, leucogneisses and granulites occur in the Central Guyana Domain (CGD) near the UatumÖAnauá Domain (UAD) boundary, southeastern Roraima (Brazil). These rocks are oriented along NE-SW and E-W trends and dip to NW and N, respectively. Single-zircon Pb evaporation results yielded 1724 ± 14 Ma and 1889 ± 3 Ma for a syn-kinematic foliated hornblende-biotite monzogranite and a granodioritic mylonite, respectively. These results point to a new tectonic event (Itã Event) in the area in addition to the 1.94-1.93 Ga (late- to post-Transamazonian) and the 1.35-0.98 Ga (K'Mudku) thermal tectonic events. This new event may be related, at least locally, with the evolution of the Columbia Supercontinent. In addition, the Itã Fault System is younger than 1.89 Ga (granodioritic mylonite age), contrasting with the Barauana high-grade lineament and 1.94 Ga polydeformed rocks, pointing to the needs of a major revision of lithostratigraphic column currently proposed for the CGD as well as the CGD and UAD boundary.

  6. The population structure of two sympatric hermit-crab species on a subtidal rocky shore of an island in southeastern Brazil.

    PubMed

    Lima, Daniel J M; Cobo, Valter J; De Aquino, Mariana A B; Fransozo, Adilson

    2014-12-01

    The main goal of this investigation was to characterize the population structure and shell occupancy of two sympatric hermit-crab species, Pagurus brevidactylus and Paguristes tortugae. The study was undertaken at Couves Island on the southeastern coast of Brazil, from March 2010 through February 2011, on subtidal rocky bottoms. Specimens were collected by SCUBA diving sessions. A total of 195 individuals of P. brevidactylus and 132 of P. tortugae were examined. Both populations showed unimodal size-frequency distributions, which were non-normal for P. brevidactylus and normal for P. tortugae. The median size of P. brevidactylus was significantly smaller than P. tortugae; in both species, males were significantly larger than females. For both, juveniles and ovigerous females were recorded in all size classes and in almost the entire sampling period. No significant departures from the 1:1 sex ratio were detected, although some size classes were skewed. Overlaps in shell occupation were recorded. Pagurus brevidactylus and P. tortugae showed similar population features; they reached sexual maturity at small sizes, and the nearly year-round presence of young and ovigerous females suggests continuous reproduction. These inter-specific interactions involving resource partitioning suggest a regulatory process that is probably part of the equilibrium strategy of these populations. PMID:25590715

  7. Status of Aceria guerreronis Keifer (Acari: Eriophyidae) as a pest of coconut in the state of Sao Paulo, southeastern Brazil.

    PubMed

    Oliveira, D C; de Moraes, G J; Dias, C T S

    2012-08-01

    The coconut mite, Aceria guerreronis Keifer, is one of the main pests of coconut palms (Cocos nucifera) in northeastern Brazil. The objective of this study was to evaluate the levels of the coconut mite and other mites on coconut palms in the state of São Paulo and to estimate the possible role of predatory mites in the control of this pest. The effect of cultivated genotypes and sampling dates on the mite populations was also estimated. We sampled attached fruits, leaflets, inflorescences, and fallen fruits. The coconut mite was the main phytophagous mite found on attached and fallen fruits, with average densities of 110.0 and 20.5 mites per fruit, respectively. The prevalent predatory mites on attached and fallen fruits were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), both Melicharidae. On leaflets, the tenuipalpids Brevipalpus phoenicis (Geijsks) and Tenuipalpus coyacus De Leon and the tetranychid Oligonychus modestus (Banks) were the predominant phytophagous mites. On both leaflets and inflorescences, the predominant predatory mites belonged to the Phytoseiidae. Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), predators widely associated with the coconut mite in northeastern Brazil and several other countries, were not found. The low densities of the coconut mite in São Paulo could be related to prevailing climatic conditions, scarcity of coconut plantations (hampering the dispersion of the coconut mite between fields), and to the fact that some of the genotypes cultivated in the region are unfavorable for its development. PMID:23950068

  8. The long-term control of vegetation and woody debris on channel and flood-plain evolution: insights from a paired catchment study in southeastern Australia

    NASA Astrophysics Data System (ADS)

    Brooks, Andrew P.; Brierley, Gary J.; Millar, Robert G.

    2003-03-01

    Numerous case studies have demonstrated that alluvial and semi-alluvial rivers in SE Australia have undergone dramatic metamorphosis in historical times. However, very few studies place these changes within a long-term evolutionary context. As a consequence, the magnitude of, and ultimate controls on, the changes to river form and processes are not fully appreciated. In this study, a paired catchment analysis is undertaken between two moderate-sized sand-bed rivers in East Gippsland, Australia. From the Thurra River, direct insight is gained into the predisturbance control exerted by riparian vegetation and wood in a lowland alluvial river. This river is effectively in the same condition today as it was at the time of the arrival of Europeans in Australia. In contrast, the adjacent Cann River, which has been settled by Europeans for 150 years, but was previously very similar to the Thurra River, exhibits stark differences today. Channel morphodynamics observed within the Thurra River, when coupled with historical and geomorphic evidence for the former condition of the Cann River, provide a detailed reference by which the recent changes to the Cann River are measured. Chronostratigraphic evidence from both flood plains places recent channel behavior within an evolutionary context extending well into the Pleistocene. Since European settlement, the study reach of the Cann River has experienced a 360% increase in channel depth, a 240% increase in channel slope, a 700% increase in channel capacity, and up to a 150-fold increase in the rate of lateral channel migration. The contemporary condition of the Cann River channel differs profoundly to that which has prevailed over at least the previous 27 ka. The first-order control on the historical channel metamorphosis is the removal of riparian vegetation and woody debris (WD). Numerous thresholds have been crossed as a result of historical channel changes, particularly the relationship between average length of woody debris

  9. Anurans in a forest remnant in the transition zone between cerrado and Atlantic Rain Forest domains in Southeastern Brazil.

    PubMed

    Pirani, Renata M; Nascimento, Luciana B; Feio, Renato N

    2013-09-01

    This study presents the species richness, temporal distribution and reproductive activity of anurans from the Uaimií State Forest (Floresta Estadual do Uaimií - FLOE Uaimií), situated in the Quadrilátero Ferrífero region, municipality of Ouro Preto, Minas Gerais state, Brazil. Field activities were performed monthly from September 2009 to August 2010. We recorded 36 anurans species, distributed in 10 families. The greatest richness of the sampled sites corresponds to a permanent rivulet in a secondary forest. The majority of anuran species presented seasonal vocalization activity pattern, mainly in the rainy season. The anuran species composition of FLOE Uaimií is similar to others studied areas from the Quadrilátero Ferrífero region. PMID:24068093

  10. Validation of the EROSION 3D model on micro-catchment scale in Mato Grosso/Brazil

    NASA Astrophysics Data System (ADS)

    Schultze, Nico; Schindewolf, Marcus; Lamparter, Gabriele; Nóbrega, Rodolfo; Amorim, Ricardo S. S.; Schmidt, Jürgen

    2015-04-01

    Accelerated land use changes in Mato Grosso caused soil degradation and contamination of water resources. Soil erosion models are increasingly being used, in order to simulate the involved physical processes and to predict the effects of soil erosion control measures. In this regard the process based EROSION 3D soil loss simulation model could be applied in the region. A comprehensive application on regional scale demands proofed model qualities on smaller scales. The paper aims on calibration and validation of surface runoff and related sediment losses by water erosion for a gauged cropland micro-catchment, which is representative for study area. Model parameterization was performed by own soil analysis, artificial rainfall simulations and observations. Temporal discrete soil parameter sets were interpolated continuously on the yearly course by applying planting dates, harvesting dates and phenological plant cover changes as fundamentals. Discharge hydrographs were calibrated successfully and verified for several rainfall events. Calculated sediment losses exceed observed results by two orders of magnitude. Since the model was validated on plot scale and erosion-deposition pattern were tested on plausibility, the only acceptable conclusion are insufficiently measured sediment concentrations. Further investigation should focus on water sampling and calibration of turbidity probes under local conditions. However, we assume that our results are sufficient to increase the scale of model application in order to describe status quo scenarios and effects of land use and climate change in the region.

  11. Differential metallothionein, reduced glutathione and metal levels in Perna perna mussels in two environmentally impacted tropical bays in southeastern Brazil.

    PubMed

    Lavradas, Raquel T; Rocha, Rafael C C; Bordon, Isabella C A C; Saint'Pierre, Tatiana D; Godoy, José M; Hauser-Davis, Rachel A

    2016-07-01

    Mussel farming is an important economic activity in Brazil, and these organisms are consumed by the majority of the population in most coastal zones in the country. However, despite the increasing pollution of aquatic ecosystems in Brazil, little is known about the biochemical activity in mussels in response to metal exposure. In this context, the aim of the present study was to investigate metal and metalloid exposure effects in Perna perna mussels, by determining metal levels, the induction of metallothionein (MT) synthesis, and oxidative stress, in the form of reduced glutathione (GSH) in 3 contaminated areas from the Guanabara Bay in comparison to a reference site, Ilha Grande Bay, both in summer and winter. Metal and metalloid concentrations were also compared to Brazilian and international guidelines, to verify potential health risks to human consumers. Mussels from all sampling sites were shown to be improper for human consumption due to metal contamination, including Ilha Grande Bay, which has previously been considered a reference site. Several statistically significant correlations and seasonal differences were observed between MT, GSH and metals and metalloids in both analyzed tissues. A Discriminant Canonical Analysis indicated that the digestive gland is a better bioindicator for environmental contamination by metals and metalloids in this species and offers further proof that MT variations observed are due to metal exposure and not oxidative stress, since GSH influence for both muscle tissue and the digestive glands was non-significant in this analysis. These results show that P. perna mussels are an adequate sentinel species for metal contamination with significant effects on oxidative stress and metal exposure biomarkers. To the best of our knowledge, this is the first study to report metals, metalloids, MT and GSH levels in the muscle tissue of this species. PMID:26994306

  12. Seismic Interpretation of Igneous Intrusions and Their Implications for an Unconventional Petroleum System in Southeastern Parnaiba Basin, Northeastern Brazil.

    NASA Astrophysics Data System (ADS)

    Porto, A. L.; Pereira, E.

    2014-12-01

    After almost two decades of little exploratory effort in the Parnaiba Basin, recent gas discoveries have revived the economic interest in this region. A new exploratory play was successfully tested, confirming the efficiency of the igneous sills triggering the thermal effect on source rocks maturation, and also playing an important role as unconventional trap and seal. Parnaiba Basin was affected by two magmatic events: the Mosquito Formation (Average Age: 178 Ma) and the Sardinha Formation (Average Age: 124 Ma), both characterized by basic magmatic rocks. Ten 2D seismic lines, located in the southeastern Parnaiba Basin, were systematically interpreted in order to identify the main diabase sills geometry, some possible emplacement controls and further implications for an unconventional petroleum system. The identified sills were classified in three types: A, B, and C, according to their dominant geometries and the stratigraphic position of their host rocks. From base to top, Type A sills intrude the Pre-Silurian Sequence, that fills in graben structures of the basement. They have short lateral continuity and saucer-shaped geometry. The main graben faults seem to control the steeper sills, which seem to feed upper sills. Type B sills intrude mainly the Silurian Sequence and have a very long lateral continuity when intruding the shales of Tiangua Formation, in which they are mainly horizontal tabular. Type C sills intrude the top of the Devonian Sequence and have two main geometries: saucer-shaped and horizontal tabular. By correlation to the surface geology of the area, Type C sills are interpreted as Sardinha Formation (Lower Cretaceous). Considering an unconventional hydrocarbon play in the area, some potential trap features associated with sill geometry, were identified, using analogous plays successfully tested in recent discoveries. These traps are associated to a specific sill geometry locally known as "inverted saucer-shaped sill". This shape consists into a

  13. Long-distance lava correlation in the Paraná volcanic province along the Serra Geral cuesta, southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Hartmann, L. A.; Arena, K. R.; Duarte, S. K.; Pertille, J.

    2013-09-01

    The capability of determining the flow-by-flow stratigraphy and the long-distance correlation of lava flows in large continental volcanic provinces leads to a considerable advance in the understanding of processes related to generation and evolution of the lavas. The Paraná volcanic province is exposed along the Serra Geral cuesta of southern Brazil in a steeply inclined, 1,000-m-high section starting 40-m above sea level. Each of the 10-20 pahoehoe flows and rhyodacite flow units has a unique chemical composition. Integrated with field stratigraphy and gamma-spectrometric measurements, this leads to the establishment of the correct stratigraphic sequence in each of three different vertical sections. The number of flows integrating the three serras is 26 ("serra" is a mountain range in Portuguese). Each serra has basaltic andesites at the base, whereas rhyodacites are intercalated with basaltic andesites at the top. Three basaltic andesite flows and one rhyodacite flow unit are correlated between Serra Umbu and Serra Boa Vista (10 km). In the Serra Faxinal, a thick (170 m) sill at the base correlates with flow 13F, whereas a dike-sill in the Graxaim quarry (24 km distance) correlates with flow 3F. One basaltic andesite and two rhyodacite flow units correlate between Serra Faxinal and Serra Umbu (50 km). The results are most significant for the understanding of large tracts of continental volcanic provinces with use of common geochemical and gamma-spectrometric techniques.

  14. Annual, seasonal and spatial abundance of the seabob shrimp Xiphopenaeus kroyeri (Decapoda, Penaeidae) off the Southeastern coast of Brazil.

    PubMed

    Heckler, Gisele S; Lopes, Mateus; Simões, Sabrina M; Shimizu, Roberto M; Costa, Rogerio C da

    2014-09-01

    We investigated the influence of environmental factors in spatial and temporal distribution of the seabob shrimp Xiphopenaeus kroyeri in Santos Bay and São Vicente Estuary, state of São Paulo, Brazil. Monthly samples were obtained, from May 2008 through April 2010, from four locations in the estuary and four in the bay. No individual was collected in the estuary and this was attributed to the low salinity means recorded in this environment. We collected 109,153 individuals in the bay and there was no difference in abundance between the two years comprised by the study period. The similarity in spatial distribution can be related to sediment grain size that in all sampling locations showed great amount of very fine sand. The largest amount of reproductive females was obtained in early 2010, when temperature was high, and this could have increased the juvenile recruitment in April 2010. According to our results, the distribution of X. kroyeri in the study area is influenced by temperature, which is related to reproduction, and salinity, limiting the entrance of individuals in the estuarine region. PMID:25098310

  15. Water quality and diversity of yeasts from tropical lakes and rivers from the Rio Doce basin in Southeastern Brazil

    PubMed Central

    Medeiros, Adriana O.; Missagia, Beatriz S.; Brandão, Luciana R.; Callisto, Marcos; Barbosa, Francisco A. R.; Rosa, Carlos A.

    2012-01-01

    Yeast communities were assessed in 14 rivers and four lakes from the Doce River basin in Brazil, during the rainy and dry seasons of the years 2000 and 2001. Water samples were collected at the subsurface in all sites. The following physical and chemical parameters were measured: temperature, dissolved oxygen, pH, electrical conductivity, total phosphorus, ortho-phosphate, ammonium, nitrate, nitrite and total nitrogen and the counts of faecal coliforms and heterotrophic bacteria were carried out to characterize the aquatic environmental sampled. The yeast counts were higher in aquatic environments with the highest counts of coliform and heterotrophic bacteria. These environments receive a high influx of domestic and industrial waste. A total of 317 isolates identified in forty eight yeast species were recorded in the sites sampled and the specie Aureobasidium pullulans were found in eleven out of eighteen sites sampled and some opportunistic pathogens such as the yeast species Candida krusei were isolated only in the polluted rivers with a positive correlation with the biotic and abiotic parameters that indicate sewage contamination. PMID:24031990

  16. Domestic dogs in Atlantic forest preserves of south-eastern Brazil: a camera-trapping study on patterns of entrance and site occupancy rates.

    PubMed

    Srbek-Araujo, A C; Chiarello, A G

    2008-11-01

    Presence of exotic species in forest remnants is a major concern for the conservation of wild species, not only on islands, where potential impact is higher. Although the problem is widespread and increasing, there are few studies on Neotropical forests. Here we quantify the occurrence of domestic dogs (Canis lupus familiaris) in an Atlantic forest reserve in south-eastern Brazil (Santa Lúcia Biological Station--SLBS). Throughout two years of monitoring with camera traps (2,142 camera-days), 25 records of 16 individual dogs were obtained in the interior of SLBS, making dogs the fourth most frequently recorded species of mammals in general and the first-ranking among Carnivora, ahead of the ocelot and puma, the top two terrestrial predators present in SLBS. Dogs entered the forest year round, in almost half of the sampled months (48%), and predominantly during daytime (89%). They were detected in various trails inside the reserve, but mostly in areas nearest to the reserve's border (<200 m from the edge). Record rates of domestic dogs did not correlate significantly with climate variables, with frequency of mammal records and richness in general, or with any particular mammal species (Spearman rank correlation, p > 0.05 in all cases), suggesting an erratic, non-seasonal pattern of entrance in the reserve. Data indicate that domestic dogs can be abundant and frequent visitors to little disturbed Atlantic forest reserves even when these are located in regions of low density of human population. The potential impact to native fauna is discussed. PMID:19197494

  17. Effects of Fragmentation and Sea-Level Changes upon Frog Communities of Land-Bridge Islands off the Southeastern Coast of Brazil

    PubMed Central

    Bittencourt-Silva, Gabriela B.; Silva, Hélio R.

    2014-01-01

    We investigate the composition of anuran communities of land-bridge islands off the southeastern coast of Brazil. These islands provide natural long-term experiments on the effects of fragmentation in the Brazilian Atlantic Forest (BAF). We hypothesize that Pleistocene sea-level changes, in combination with other abiotic variables such as area and habitat diversity, has affected anuran species richness and community composition on these islands. Data from the literature and collections databases were used to produce species lists for eight land-bridge islands and for the mainland adjacent to the islands. We assess the effects of area, number of breeding habitats and distance to the mainland upon anuran species richness on land-bridge islands. Additionally we use nestedness analysis to quantify the extent to which the species on smaller and less habitat-diverse islands correspond to subsets of those on larger and more diverse ones. We found that area has both direct and indirect effects on anuran species richness on land-bridge islands, irrespective of distance to the mainland. However, on islands with comparable sizes, differences in species richness can be attributed to the number and quality of breeding habitats. Anuran communities on these islands display a nested pattern, possibly caused by selective extinction related to habitat loss. Common lowland pond-breeders were conspicuous by their absence. In the BAF, the conservation of fragments with a high diversity of breeding habitats could compensate for the generally negative effect of small area upon species richness. We suggest that sea-level changes have an important role in shaping composition of anuran species on coastal communities. PMID:25068643

  18. New U-Pb ages and lithochemical attributes of the Ediacaran Rio Doce magmatic arc, Araçuaí confined orogen, southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Gonçalves, Leonardo; Farina, Federico; Lana, Cristiano; Pedrosa-Soares, Antônio C.; Alkmim, Fernando; Nalini, Hermínio A.

    2014-07-01

    The Araçuaí orogen of southeastern Brazil, together with its counterpart located in Africa, the West Congo belt, formed through closure of a gulf connected to the Adamastor Ocean by the end of the Ediacaran and beginning of the Cambrian. Convergence of the margins of the gulf led to the development of the Rio Doce magmatic arc between 630 Ma and 580 Ma on a continental basement mostly composed of Rhyacian orthogneisses. The Rio Doce arc mainly consists of tonalite-granodiorite batholiths, generally crowded with mafic to dioritic enclaves, and minor gabbronorite-enderbite-charnockite plutons, suggesting mixing processes involving crustal and mantle sources. We investigate the basement, magma sources and emplacement ages of the Rio Doce arc. Our data suggest the arc comprises three main granitic rock groups: i) Opx-bearing rocks mostly of enderbite to charnockite composition; ii) enclave-rich tonalite-granodiorite (ETG); and iii) enclave-poor granite-granodiorite with minor tonalite (GT). The Opx-bearing rocks are magnesian, calc-alkalic to alkali-calcic and metaluminous. Together, the ETG and GT rock groups range in composition from tonalite to granite, are metaluminous to slightly peraluminous, show a predominantly medium- to high-K, expanded calc-alkaline signature, and other geochemical and isotopic attributes typical of a pre-collisional volcanic arc formed on a continental margin setting. Mineralogical, chemical, and geochronological data suggest the involvement of HT-melting of granulitic (H2O-depleted) sources of Rhyacian age for the generation of Opx-bearing granitic rocks, additionally to magma mixing and fractional crystallization processes. In conclusion, the studied rock groups of the Rio Doce arc were likely formed by interactions of mantle and crustal processes, in an active continental margin setting. These processes involved ascent of mantle magmas that induced partial melting on the continental basement represented by the Rhyacian gneisses.

  19. Physically-based slope stability modelling and parameter sensitivity: a case study in the Quitite and Papagaio catchments, Rio de Janeiro, Brazil

    NASA Astrophysics Data System (ADS)

    de Lima Neves Seefelder, Carolina; Mergili, Martin

    2016-04-01

    We use the software tools r.slope.stability and TRIGRS to produce factor of safety and slope failure susceptibility maps for the Quitite and Papagaio catchments, Rio de Janeiro, Brazil. The key objective of the work consists in exploring the sensitivity of the geotechnical (r.slope.stability) and geohydraulic (TRIGRS) parameterization on the model outcomes in order to define suitable parameterization strategies for future slope stability modelling. The two landslide-prone catchments Quitite and Papagaio together cover an area of 4.4 km², extending between 12 and 995 m a.s.l. The study area is dominated by granitic bedrock and soil depths of 1-3 m. Ranges of geotechnical and geohydraulic parameters are derived from literature values. A landslide inventory related to a rainfall event in 1996 (250 mm in 48 hours) is used for model evaluation. We attempt to identify those combinations of effective cohesion and effective internal friction angle yielding the best correspondence with the observed landslide release areas in terms of the area under the ROC Curve (AUCROC), and in terms of the fraction of the area affected by the release of landslides. Thereby we test multiple parameter combinations within defined ranges to derive the slope failure susceptibility (fraction of tested parameter combinations yielding a factor of safety smaller than 1). We use the tool r.slope.stability (comparing the infinite slope stability model and an ellipsoid-based sliding surface model) to test and to optimize the geotechnical parameters, and TRIGRS (a coupled hydraulic-infinite slope stability model) to explore the sensitivity of the model results to the geohydraulic parameters. The model performance in terms of AUCROC is insensitive to the variation of the geotechnical parameterization within much of the tested ranges. Assuming fully saturated soils, r.slope.stability produces rather conservative predictions, whereby the results yielded with the sliding surface model are more

  20. A House for Two--Double Bacterial Infection in Euplotes woodruffi Sq1 (Ciliophora, Euplotia) Sampled in Southeastern Brazil.

    PubMed

    Senra, Marcus V X; Dias, Roberto J P; Castelli, Michele; Silva-Neto, Inácio D; Verni, Franco; Soares, Carlos A G; Petroni, Giulio

    2016-02-01

    Several ciliated protists form symbiotic associations with a diversity of microorganisms, leading to drastic impact on their ecology and evolution. In this work, two Euplotes spp. sampled in Rio de Janeiro, Brazil, were identified based on morphological and molecular features as Euplotes woodruffi strain Sq1 and E. encysticus strain Sq2 and investigated for the presence of endosymbionts. While E. woodruffi Sq1 stably hosts two bacterial populations, namely Polynucleobacter necessarius (Betaproteobacteria) and a new member of the family "Candidatus Midichloriaceae" (Alphaproteobacteria, Rickettsiales), here described as "Candidatus Bandiella woodruffii," branching with a broad host range bacterial group found in association with cnidarians, sponges, euglenoids, and some arthropods; in E. encysticus Sq2 no symbiotic bacterium could be detected. The dispersion ability of this novel bacterium was tested by co-incubating E. woodruffi Sq1 with three different ciliate species. Among the tested strains "Ca. B. woodruffii" could only be detected in association with E. encysticus Sq2 with a prevalence of 20 % after 1 week and 40 % after 2 weeks, maintaining this level for up to 6 months. Nevertheless, this apparent in vitro association was abolished when E. woodruffi Sq1 donor was removed from the microcosm, suggesting that this bacterium has the capacity for at least a short-term survival outside its natural host and the aptitude to ephemerally interact with other organisms. Together, these findings strongly suggest the need for more detailed investigations to evaluate the host range for "Ca. B. woodruffii" and any possible pathogenic effect of this bacterium on other organisms including humans. PMID:26381539

  1. Atmospheric organic and inorganic nitrogen inputs to coastal urban and montane Atlantic Forest sites in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    de Souza, Patricia A.; Ponette-González, Alexandra G.; de Mello, William Z.; Weathers, Kathleen C.; Santos, Isimar A.

    2015-06-01

    Tropical regions are currently experiencing changes in the quantity and form of nitrogen (N) deposition as a result of urban and industrial emissions. We quantified atmospheric N inputs to two coastal urban and two montane (400 m and 1000 m) Atlantic Forest sites downwind of the Metropolitan Region of Rio de Janeiro (MRRJ), Brazil, from August 2008 to August 2009. Concentrations of total dissolved nitrogen (TDN), dissolved inorganic nitrogen (DIN) and urea were measured in bulk precipitation at all sites, as well as in canopy throughfall in the lower montane forest. Dissolved organic nitrogen (DON) was calculated as the difference between TDN and DIN (NH4+ + NO3- + NO2-). Annual volume-weighted mean bulk concentrations of all N species were higher at the coastal urban than montane forest sites, with DON accounting for 32-56% and 26-32%, respectively, of the TDN concentration in bulk precipitation. Bulk deposition of TDN ranged 12.1-17.2 kg N ha- 1 yr- 1 and tended to decrease with increasing distance from the coastal urban region. In the lower montane forest, throughfall TDN flux, 34.3 kg N ha- 1 yr- 1, was over 2-fold higher than bulk TDN deposition, and DON comprised 57% of the total N deposited by throughfall to the forest soil. Urea comprised 27% of DON in throughfall compared to up to 100% in bulk precipitation. Our findings show that DON is an important, yet understudied, component of TDN deposition in tropical forest regions, comprising one-third to greater than one-half of the N deposited in rainfall and throughfall. Further, in this lower montane Atlantic Forest site, throughfall DIN flux was 1.5-3 fold higher than the suggested empirical critical load for humid tropical forests, highlighting the potential for increasing N pollution emitted from the MRRJ to impact N cycling in adjacent ecosystems.

  2. Paleobiogeoclimatic scenarios of the Late Quaternary inferred from fluvial deposits of the Quadrilátero Ferrífero (Southeastern Brazil)

    NASA Astrophysics Data System (ADS)

    Barros, Luiz Fernando de Paula; Coe, Heloísa Helena Gomes; Seixas, Amanda Pacheco; Magalhães, Antônio Pereira, Jr.; Macario, Kita Chaves Damasio

    2016-04-01

    The Quadrilátero Ferrífero is an important mineral province in Southeastern Brazil and has one of the largest iron ore reserves in the world. Previous work in this region has indicated that the formation of fluvial successions with duricrusts coincided with drier/cooler climatic phases alternating with moister/warmer periods during which the formation of fluvial successions without duricrusts occurred. For the construction of this proposal, ages of fluvial sediments obtained through Optically Stimulated Luminescence (OSL) were associated with data from the literature on paleobioclimatic scenarios. Therefore, using these observations as a starting point, this paper aims to investigate evidence of bioclimatic oscillations obtained directly from the fluvial successions and discuss its influence on the geomorphogenis of local river valleys. For this purpose, phytolith, carbon isotope and granulometric analyses were carried out, as well as dating of sediments using OSL and of soil organic matter through radiocarbon. The results show that in the oldest depositional succession (DS1 - about 34ka) the predominant phytoliths are those of bulliform polyedric, elongate, acicular and globular granulate types and δ13C values are typical of C3 plants. On the other hand, despite having a similar phytolith assemblage (abundance of bulliform polyedric, elongate, bulliform cuneiform, acicular, globular psilate and bilobate flat/concave types), the fluvial successions associated with significant conglomeratic duricrusts (DS2 and DS3) present a dominance of δ13C values characteristic of C4 plants. The Bi index indicates water stress in all the successions, and the Ic index suggests decreasing temperatures with depth in DS3. Thus, the three fluvial successions indicate a savanna-like environment, but depositional successions DS2 (∼27ka) and DS3 show drier/cooler climatic conditions when compared to DS1 and to the present-day regime. Both scenarios evolved under conditions of the

  3. Identification and molecular phylogeny of coagulase-negative staphylococci isolates from Minas Frescal cheese in southeastern Brazil: Superantigenic toxin production and antibiotic resistance.

    PubMed

    Casaes Nunes, Raquel Soares; Pires de Souza, Camilla; Pereira, Karen Signori; Del Aguila, Eduardo Mere; Flosi Paschoalin, Vânia Margaret

    2016-04-01

    Minas Frescal is a typical Brazilian fresh cheese and one of the most popular dairy products in the country. This white soft, semiskimmed, nonripened cheese with high moisture content is obtained by enzymatic coagulation of cow milk using calf rennet or coagulants, usually in industrial dairy plants, but is also manufactured in small farms. Contamination of Minas Frescal by several staphylococci has been frequently reported. Coagulase-negative staphylococci (CNS) strains are maybe the most harmful, as they are able to produce heat-stable enterotoxins with super antigenic activities in food matrices, especially in dairy products such as soft cheeses. The aim of the present study was to investigate the presence of CNS strains in Minas Frescal marketed in southeastern Brazil concerning the risk of staphylococci food poisoning by the consumption of improperly manufactured cheese and the possibility of these food matrices being a reservoir of staphylococcal resistance to antimicrobials. Ten distinct CNS strains were found in 6 cheeses from distinct brands. The most frequent species were Staphylococcus saprophyticus (40%), Staphylococcus xylosus (30%), Staphylococcus sciuri (20%), and Staphylococcus piscifermentans (10%). Three strains were identified to the Staphylococcus genera. Three major species groups composed of 3 refined clusters were grouped by phylogenetic analyses with similarities over to 90%. All CNS strains carried multiple enterotoxin genes, with high incidence of sea and seb (90 and 70%, respectively), followed by sec/see, seh/sei, and sed with intermediate incidence (60, 50, and 40%, respectively), and, finally, seg/selk/selq/selr and selu with the lowest incidence (20 and 10%, respectively). Real-time reverse transcription PCR and ELISA assays confirmed the enteroxigenic character of the CNS strains, which expressed and produced the enterotoxins in vitro. The CNS strains showed multiresistance to antimicrobial agents such as β-lactams, vancomycin, and

  4. Leaf δ15N as an indicator of arbuscular mycorrhizal nitrogen uptake in a coastal-plain forest (restinga forest) at Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Mardegan, S. F.; Valadares, R.; Martinelli, L.

    2013-12-01

    Restinga diversity contrasts with a series of adverse environmental conditions that constrain their development, including nutrient limitation. In this sense, the mutualistic symbiosis between plants and arbuscular mycorrhizal fungi (AMF) may contribute in nutrient acquisition, including nitrogen. However, this association deeply affects plant nitrogen isotopic composition (δ15N), since assimilation processes and biochemical reactions within the fungi may reflect in a delivered product with an isotopic composition about 8 to 10 ‰ lower than that observed at the fungal symbiont per se. Here we assessed if the association with AMF affects δ15N values of plant species from a coastal-plain forest (restinga forest) at Southeastern Brazil. Accordingly, we analyzed the nutritional and isotopic compositions from ecosystem key-compartments (soil, litter and leaves), relating plant δ15N with the colonization rates. The study was carried out in a permanent plot (1 ha) at a coastal-plain forest (restinga forest) at the Serra do Mar State Park, SP, Brazil. Sampled vegetation is characterized by the lack of a well-defined stratification and a rather open canopy. It also comprises trees ranging from 10 to 15-m high. Soils are deep and sandy, being characterized by high acidity, nutrient deficiency and a dense litter cover. We randomly collected five samples (250 mg) from topsoil (0-10 cm) and five to ten leaves from individuals belonging to 16 plant species of high relevance within the site (IVI index). We also collected superficial (0-10 cm depth) fine roots (5 g) and 13 samples (100 g) of fine litter next to the individuals sampled. Soil samples were air-dried, sieved, homogenized and used in the physical-chemical characterization. The remainder was ground to a fine powder to determine nitrogen concentrations and δ15N values. Leaves were dried at 50 °C, finely milled and used for the determination of nitrogen concentrations, C/N ratios and δ15N values. Root samples were

  5. Brazil.

    PubMed

    1985-09-01

    Brazil's population in 1985 was 135 million, with an annual growth rate (1982) of 2.3%. The infant mortality rate (1981) was 92/1000, and life expectancy stood at 62.8 years. 76% of the adult population was literate. Brazil is a federal republic which recognizes 5 political parties. 55% of the population is Portuguese, Italian, German, Japanese, African, or American Indian; 38% is white. Of the work force of 50 million, 35% are engaged in agriculture, 25% work in industry, and 40% are employed in services. Trade union membership totals 6 million. The agricultural sector accounts for 12% of the GDP and 40% of exports. Brazil is largely self-sufficient in terms of food. The GDP was US$218 billion in 1984, with an annual growth rate of 4%. Per capita GDP was US$1645. Brazil's power, transportation, and communications systems have improved greatly in recent years, providing a base for economic development. High inflation rates have been a persistent problem. PMID:12178118

  6. Organic biomarker records spanning the last 34,800 years from the southeastern Brazilian upper slope: links between sea surface temperature, displacement of the Brazil Current, and marine productivity

    NASA Astrophysics Data System (ADS)

    Lourenço, Rafael André; de Mahiques, Michel Michaelovitch; Wainer, Ilana Elazari Klein Coaracy; Rosell-Melé, Antoni; Bícego, Márcia Caruso

    2016-06-01

    Collective assessment of marine and terrigenous organic biomarkers was performed on a sediment core spanning the last 34,800 years on the upper slope southeast of Brazil to verify the signatures of climatic variations in sea surface temperature (SST), marine productivity, and the flux of terrigenous material in this region. This evaluation is based on marine and terrigenous proxies including alkenones, chlorins, aliphatic hydrocarbons, n-alcohols, and fatty acids. This first report of organic biomarker data for this region confirms a correlation between SST, changes in terrigenous organic matter flow into the ocean, and marine productivity over the last 34.8 ka as a response to the displacement of the Brazil Current. Conditions prevailing during marine isotopic stage (MIS) 3 may be considered intermediate between the last glacial maximum (LGM) and the Late Holocene. For MIS 2, a period of low relative sea level, it was verified that the lowest SSTs were associated with the LGM and higher marine productivity. SST increased by up to 4.4 °C between the LGM and the Holocene. This reveals synchronicity between SST on the southeastern Brazilian upper slope and the North Atlantic Ocean SST records reported in earlier studies.

  7. Parameters from the community of leaf-litter frogs from Estação Ecológica Estadual Paraíso, Guapimirim, Rio de Janeiro State, southeastern Brazil.

    PubMed

    Rocha, Carlos F D; Vrcibradic, Davor; Kiefer, Mara C; Siqueira, Carla C; Almeida-Gomes, Mauricio; Borges Júnior, Vitor N T; Hatano, Fábio H; Fontes, Angélica F; Pontes, Jorge A L; Klaion, Thais; Gil, Lívia O; Sluys, Monique Van

    2011-12-01

    We studied the leaf-litter frog community of Estação Ecológica Estadual Paraíso, in Guapimirim, Rio de Janeiro State, southeastern Brazil. Herein we combined three sampling methods (large plots, visual encounter surveys and pit-fall traps) to present data on species composition, richness, relative abundance and densities. The local assemblage of frogs associated to the leaf-litter was composed by 14 species, belonging to nine families. Haddadus binotatus, a direct-developing frog, was the most abundant species in the community. The estimated density of the local leaf-litter frog assemblage based on plot sampling was 4.3 frogs/100 m(2). Haddadus binotatus had the highest density (1.1 ind/100 m(2)). Frogs were predominantly found at night. Thoropa miliaris had the largest values of SVL (39.0 ± 10.3 mm), whereas the smallest species were Euparkerella brasiliensis (16.7 ± 2.2 mm) and E. cochranae (16.0 ± 2.7 mm). Rhinella ornata had the highest mean body mass (12.1 ± 7.5 g), and E. cochranae the lowest (0.4 ± 0.2 g). The overall frog mass was 938.6 g/ha. Our data support that higher densities of leaf-litter frogs tend to occur in the Neotropical region compared to the OldWorld tropics, tending to be higher in Central America than in South America. PMID:21971595

  8. Spatial variability in persistent organic pollutants and polycyclic aromatic hydrocarbons found in beach-stranded pellets along the coast of the state of São Paulo, southeastern Brazil.

    PubMed

    Taniguchi, Satie; Colabuono, Fernanda I; Dias, Patrick S; Oliveira, Renato; Fisner, Mara; Turra, Alexander; Izar, Gabriel M; Abessa, Denis M S; Saha, Mahua; Hosoda, Junki; Yamashita, Rei; Takada, Hideshige; Lourenço, Rafael A; Magalhães, Caio A; Bícego, Márcia C; Montone, Rosalinda C

    2016-05-15

    High spatial variability in polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, such as DDTs, and polybrominated diphenylethers was observed in plastic pellets collected randomly from 41 beaches (15 cities) in 2010 from the coast of state of São Paulo, southeastern Brazil. The highest concentrations ranged, in ng g(-1), from 192 to 13,708, 3.41 to 7554 and <0.11 to 840 for PAHs, PCBs and DDTs, respectively. Similar distribution pattern was presented, with lower concentrations on the relatively less urbanized and industrialized southern coast, and the highest values in the central portion of the coastline, which is affected by both waste disposal and large port and industrial complex. Additional samples were collected in this central area and PCB concentrations, in ngg(-)(1), were much higher in 2012 (1569 to 10,504) than in 2009/2010 (173 to 309) and 2014 (411), which is likely related to leakages of the PCB commercial mixture. PMID:27021625

  9. Sandflies (Diptera: Psychodidae) associated with opossum nests at urban sites in southeastern Brazil: a risk factor for urban and periurban zoonotic Leishmania transmission?

    PubMed

    Cutolo, Andre Antonio; Teodoro, Anna Karollina Menezes; Ovallos, Fredy Galvis; Allegretti, Silmara Marques; Galati, Eunice Aparecida Bianchi

    2014-06-01

    Sandflies associated with opossum nests are reported for the first time in the yards of residences located in the urban area of the municipality of Monte Mor, situated in the metropolitan region of Campinas, state of São Paulo, Brazil. Eleven specimens of Evandromyia cortelezzii and one of Evandromyia lenti were captured in two Didelphis albiventris nests. Ev. cortelezzii is considered a secondary vector species for the transmission of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) infantum in the Neotropics. This association may contribute to the introduction, establishment and maintenance of urban and periurban zoonotic transmission outbreaks of Leishmania and should therefore be investigated further. PMID:24789554

  10. Sandflies (Diptera: Psychodidae) associated with opossum nests at urban sites in southeastern Brazil: a risk factor for urban and periurban zoonotic Leishmania transmission?

    PubMed Central

    Cutolo, Andre Antonio; Teodoro, Anna Karollina Menezes; Ovallos, Fredy Galvis; Allegretti, Silmara Marques; Galati, Eunice Aparecida Bianchi

    2014-01-01

    Sandflies associated with opossum nests are reported for the first time in the yards of residences located in the urban area of the municipality of Monte Mor, situated in the metropolitan region of Campinas, state of São Paulo, Brazil. Eleven specimens of Evandromyia cortelezzii and one of Evandromyia lenti were captured in two Didelphis albiventris nests. Ev. cortelezzii is considered a secondary vector species for the transmission of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) infantum in the Neotropics. This association may contribute to the introduction, establishment and maintenance of urban and periurban zoonotic transmission outbreaks of Leishmania and should therefore be investigated further. PMID:24789554

  11. Hydrocarbons and trace metals in mussels in the Macaé coast: Preliminary assessment for a coastal zone under influence of offshore oil field exploration in southeastern Brazil.

    PubMed

    Santiago, Igor U; Molisani, Mauricio M; Nudi, Adriana H; Scofield, Artur L; Wagener, Angela de L R; Limaverde Filho, Aricelso M

    2016-02-15

    Concentrations of PAHs and metals were obtained from mussels collected in beaches, coastal island and estuary of the Macaé coast, the main operational basin for offshore oil exploration in Brazil. This survey provides reference levels for scenarios of increasing exploration, as well as for other areas of the coast undergoing urbanization to support exploration. As expected, urban areas such as the Macaé river estuary presented high concentrations of PAHs, although unsuspected sites such the island also presented signs of contamination. PAH in mussels originated from pyrolytic and petrogenic sources. Metals were typical of non-contaminated coastal environments, although Cr concentrations were above Brazilian Reference Levels. PMID:26763324

  12. The evolution of a tropical rainforest/grassland mosaic in southeastern Brazil since 28,000 14C yr BP based on carbon isotopes and pollen records

    NASA Astrophysics Data System (ADS)

    Ruiz Pessenda, Luiz Carlos; De Oliveira, Paulo Eduardo; Mofatto, Milene; de Medeiros, Vanda Brito; Francischetti Garcia, Ricardo José; Aravena, Ramon; Bendassoli, José Albertino; Zuniga Leite, Acácio; Saad, Antonio Roberto; Lincoln Etchebehere, Mario

    2009-05-01

    The lack of paleoecological records from the montane Atlantic Rainforest of coastal Brazil, a hotspot of biological diversity, has been a major obstacle to our understanding of the vegetational changes since the last glacial cycle. We present carbon isotope and pollen records to assess the impact of the glaciation on the native vegetation of the Serra do Mar rainforest in São Paulo, Brazil. From ca. 28,000 to ˜ 22,000 14C yr BP, a subtropical forest with conifer trees is indicative of cool and humid conditions. In agreement carbon isotopic data on soil organic matter suggest the presence of C 3 plants and perhaps C 4 plants from ˜ 28,000 to ˜ 19,000 14C yr BP. The significant increase in the sedimentation rate and algal spores from ˜ 19,450 to ˜ 19,000 14C yr BP indicates increasing humidity, associated to an erosion process between ˜ 19,000 and ˜ 15,600 14C yr BP. From ˜ 15,600 14C yr BP to present there is a substantial increase in arboreal elements and herbs, indicating more humid and warmer climate. From ˜ 19,000 to ˜ 1000 14C yr BP, δ 13C values indicated the predominance of C 3 plants. These results are in agreement with studies in speleothems of caves, which suggest humid conditions during the last glacial maximum.

  13. A new snapping species of the shrimp genus Typton Costa, 1844 (Decapoda: Palaemonidae) from the coast of São Paulo, southeastern Brazil.

    PubMed

    Almeida, Alexandre O; Anker, Arthur; Mantelatto, Fernando L

    2014-01-01

    A new species of the palaemonid shrimp genus Typton Costa, 1844, Typton fapespae sp. nov., is described based on several specimens collected in Ubatuba and São Sebastião, northern coast of the state of São Paulo, Brazil. Most specimens were found in association with sponges, including Mycale (Zygomycale) angulosa (Duchassaing & Michelotti, 1864) (Demospongiae: Mycalidae); however, one paratype from Ubatuba was extracted from a colony of the bryozoan Schizoporella errata (Waters, 1878) (Gymnolaemata: Schizoporellidae). In T. fapespae sp. nov., the posterodorsal margin of the sixth abdominal segment bears a strong median tooth, a feature shared with T. hephaestus Holthuis, 1951, T. holthusi De Grave, 2010 and T. spongicola Costa, 1844. However, the new species can be separated from each of these three species by at least two morphological features.  PMID:25081438

  14. Pollen analysis of honey and pollen collected by Apis mellifera linnaeus, 1758 (Hymenoptera, Apidae), in a mixed environment of Eucalyptus plantation and native cerrado in Southeastern Brazil.

    PubMed

    Simeão, C M G; Silveira, F A; Sampaio, I B M; Bastos, E M A F

    2015-11-01

    Eucalyptus plantations are frequently used for the establishment of bee yards. This study was carried on at Fazenda Brejão, northwestern region of the State of Minas Gerais, Brazil. This farm is covered both with native Cerrado vegetation (Brazilian savanna) and eucalyptus plantations. This paper reports on the botanic origin of pollen pellets and honey collected from honeybee (Apis mellifera) hives along a thirteen-month period (January 2004 to January 2005). The most frequent pollen types found in the pollen pellets during the rainy season were Trema micrantha (Ulmaceae), Copaifera langsdorffii (Fabaceae), an unidentified Poaceae, unidentified Asteraceae-2, Cecropia sp. 1 (Cecropiaceae) and Eucalyptus spp. (Myrtaceae); during the dry season the most frequent pollen types were Acosmium dasycarpum (Fabaceae), Cecropia sp. 1 (Cecropiaceae) and Eucalyptus spp. (Myrtaceae). Pollen grains of Baccharis sp. (Asteraceae), Cecropia sp. 1 (Cecropiaceae), Copaifera langsdorffii (Fabaceae), Mimosa nuda (Fabaceae), Eucalyptus spp. (Myrtaceae) and Trema micrantha (Ulmaceae) were present in the honey samples throughout the study period. PMID:26628236

  15. Mineralogical, micromorphological and geochemical transformations in the initial steps of the weathering process of charnockite from the Caparaó Range, southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Soares, Caroline Cibele Vieira; Varajão, Angélica Fortes Drummond Chicarino; Varajão, César Augusto Chicarino; Boulangé, Bruno

    2014-12-01

    X-ray diffraction (XRD), X-ray Fluorescence (XRF), optical microscopy, Scanning Electron Microscopy coupled with Energy Dispersive Spectrometry (SEM-EDS) and Electron Probe micro-analyser (EPMA) and Wavelength-Dispersive Spectroscopy (WDS) were conducted on charnockite from the Caparaó Suite and its alteration cortex to determine the mineralogical, micromorphological and geochemical transformations resulting from the weathering process. The hydrolysis of the charnockite occurred in different stages, in accordance with the order of stability of the minerals with respect to weathering: andesine/orthopyroxene, pargasite and alkali feldspar. The rock modifications had begun with the formation of a layer of incipient alteration due to the percolation of weathering solutions first in the pressure relief fractures and then in cleavage and mineral edges. The iron exuded from ferromagnesian minerals precipitated in the intermineral and intramineral discontinuities. The layer of incipient alteration evolves into an inner cortex where the plagioclase changes into gibbsite by direct alitisation, the ferromagnesian minerals initiate the formation of goethitic boxworks with kaolinitic cores, and the alkali feldspar initiates indirect transformation into gibbsite, forming an intermediate phase of illite and kaolinite. In the outer cortex, mostly traces of alkali feldspar remain, and they are surrounded by goethite and gibbsite as alteromorphics, characterising the formation of the isalteritic horizon that occurs along the slope and explains the bauxitization process at the Caparaó Range, SE Brazil.

  16. Chelonid herpesvirus 5 in secretions and tumor tissues from green turtles (Chelonia mydas) from Southeastern Brazil: A ten-year study.

    PubMed

    Monezi, Telma A; Mehnert, Dolores U; de Moura, Elisabeth M M; Müller, Natascha M G; Garrafa, Patrícia; Matushima, Eliana R; Werneck, Max R; Borella, Maria I

    2016-04-15

    Fibropapillomatosis (FP), a neoplastic disease characterized by the formation of multiple tumors affecting different species of sea turtles and, most often, the green turtle (Chelonia mydas), is considered one of the major threats to the survival of this species. Recent studies indicate that Chelonid herpesvirus (ChHV5) is the etiological agent of this disease, though its association with anthropogenically altered environments and the immune status of these animals also appears to contribute to disease expression and tumor formation. In this study, tumor biopsy and secretions from green turtles captured off the coast of São Paulo State, Brazil, were used in histological and molecular analyses to detect and characterize circulating ChHV5. In 40.9% of cases, the tumor histopathological findings revealed focal ballooning degeneration with intranuclear inclusion bodies, results which are suggestive of viral infection. ChHV5 was detected using polymerase chain reaction (PCR) on the animals' skin, ocular tumor biopsies, and ocular and oral secretions. The analysis of the detected ChHV5 sequences revealed two distinct genetic sequences together. Phylogenetic analysis indicated that Brazilian samples were similar to ChHV5 samples described for the Atlantic phylogeographic group and are therefore part of the same clade as the Gulf of Guinea and Puerto Rico samples. This similarity suggests a possible flow of the virus between these three regions. PMID:27016769

  17. Ecological distribution of stream macroalgal communities from a drainage basin in the Serra da Canastra National Park, Minas Gerais, Southeastern Brazil.

    PubMed

    Necchi-Júnior, O; Branco, L H Z; Branco, C C Z

    2003-11-01

    Twelve stream segments were sampled four times in 1998-1999 (one sampling per season) in the drainage basin of the upper São Francisco River (19 masculine 45'-21 masculine 25'S, 49 masculine 05'-51 masculine 30'W), situated in Serra da Canastra National Park, at altitudes ranging from 1,175 to 1,400 m. The macroalgae survey resulted in 30 species, with a predominance of Cyanophyta (12 species = 40%) and Chlorophyta (11 species = 36.5%) and a lower proportion of Rhodophyta (seven species = 23.5%). Two species, Klebsormidium rivulare (Chlorophyta) and Kyliniella latvica (Rhodophyta), were new records for Brazil. Capsosira sp. and Stigonema sp. (Cyanophyta) and the "Chantransia" stage of Batrachospermum (Rhodophyta) were the most widespread macroalgae, occurring in six sampling sites, whereas 11 species were found at only one site. The proportion of macroalgal morphological types were as follows: mats (33%), free filaments (27%), gelatinous filaments (27%), crusts (7%), tufts (3%), and gelatinous colonies (3%). The flora revealed few species in common (4%-8%) with stream macroalgae from other Brazilian regions. The macroalgal communities proved to have species richness values close to the highest values reported in previous studies. The patterns typical for stream macroalgal communities (patchy distribution and dominance of few species) were also found in this basin. However, the stream variables most influential in macroalgal distribution in this study (rocky substratum, low pH, high COD, water color, and current velocity) were essentially the same that best describe the limnological characteristics of this lotic ecosystem. In addition, this combination of variables differed sharply from results of previous studies in other Brazilian stream ecosystems. PMID:15029374

  18. Small cetaceans found stranded or accidentally captured in southeastern Brazil: bioindicators of essential and non-essential trace elements in the environment.

    PubMed

    Lemos, Leila Soledade; de Moura, Jailson Fulgencio; Hauser-Davis, Rachel Ann; de Campos, Reinaldo Calixto; Siciliano, Salvatore

    2013-11-01

    Essential (Cu, Mn, Se and Zn) and non-essential (Cd and Hg) elements were analyzed in the hepatic tissue of 22 individuals of seven different species of small cetaceans (Feresa attenuata; Orcinus orca; Pontoporia blainvillei; Sotalia guianensis; Stenella frontalis; Steno bredanensis; Tursiops truncatus) accidentally caught in fishing nets or found stranded along the northern coast of the state of Rio de Janeiro, Brazil, between 2001 and 2010. Atlantic spotted dolphin (S. frontalis) showed the highest levels of Cd (20.23μgg(-1), dry weight), while rough-toothed dolphin (S. bredanensis) showed the highest levels of Hg (825.9μgg(-1)dw) and Se (221.9μgg(-1)dw). Killer whale (O. orca) presented the highest levels of Cu (64.80μgg(-1)dw) and Zn (2220μgg(-1)dw), and Guiana dolphin (S. guianensis), the highest level of Mn (13.05μgg(-1)dw). Cu, Hg, Mn and Zn in the hepatic tissue of killer whale (O. orca), Cu, Hg, Mn, Se and Zn in the hepatic tissue of rough-toothed dolphin (S. bredanensis) and Cd and Zn in the hepatic tissue of Guiana dolphin (S. guianensis) were significantly higher when compared to other studies with these species around the world. No significant correlations were observed between element accumulation and sex, sexual maturity and body length. An analysis of the interelemental relationships in the Guiana dolphin specimens showed strong positive correlations between Cd and Se, Cu and Zn, and Hg and Se. Differences were observed in the bioaccumulation of elements between the analyzed species, probably related to each species feeding habit, and differences between different element concentrations in the different dolphin species were probably due to the preference for certain preys and their bioavailability in the environment. Thus, the bioavailability of the analyzed elements in the marine environment should also be taken in consideration. This study also presents the first data ever reported for pygmy killer whale (F. attenuata) regarding trace

  19. Importance of land use update during the calibration period and simulation of water balance response to land use change in the upper Rio das Mortes Catchment (Cerrado Biome, Central-Western Brazil)

    NASA Astrophysics Data System (ADS)

    Lamparter, Gabriele; Kovacs, Kristof; Nobrega, Rodolfo; Gerold, Gerhard

    2015-04-01

    Changes in the hydrological balance and following degradation of the water ecosystem services due to large scale land use changes are reported from agricultural frontiers all over the world. Traditionally, hydrological models including vegetation and land use as a part of the hydrological cycle use a fixed distribution of land use for the calibration period. We believe that a meaningful calibration - especially when investigating the effects of land use change on hydrology - demands the inclusion of land use change during the calibration period into the calibration procedure. The SWAT (Soil and Water Assessment Tool) model is a process-based, semi-distributed model calculating the different components of the water balance. The model bases on the definition of hydrological response units (HRUs) which are based on soil, vegetation and slope distribution. It specifically emphasises the role of land use and land management on the water balance. The Central-Western region of Brazil is one of the leading agricultural frontiers, which experienced rapid and radical deforestation and agricultural intensification in the last 40 years (from natural Cerrado savannah to cattle grazing to intensive corn and soya cropland). The land use history of the upper Rio das Mortes catchment (with 17500 km²) is reasonably well documented since the 1970th. At the same time there are almost continuous climate and runoff data available for the period between 1988 and 2011. Therefore, the work presented here shows the model calibration and validation of the SWAT model with the land use update function for three different periods (1988 to 1998, 1998 to 2007 and 2007 to 2011) in comparison with the same calibration periods using a steady state land use distribution. The use of the land use update function allows a clearer identification which changes in the discharge are due to climatic variability and which are due to changes in the vegetation cover. With land use update included into the

  20. Ecological assessment of a southeastern Brazil reservoir

    EPA Science Inventory

    Abstract: Reservoirs are artificial ecosystems with multiple functions having direct and indirect benefits to humans; however, they also cause ecological changes and influence the composition and structure of aquatic biota. Our objectives were to: (1) assess the environmen...

  1. Pollinators of Oxypetalum (Asclepiadaceae) in southeastern Brazil.

    PubMed

    Vieira, M F; Shepherd, G J

    1999-11-01

    Floral visitors of seven species of Oxypetalum were registered in Viçosa, State of Minas Gerais. O. appendiculatum, O. banksii subsp, banksii, O. alpinumn var. alpinum and O. pachyglossum are pollinated by wasps, being Polybia ignobilis (Vespidae) a pollinator of these four species. It seems that P ignobilis promotes interspecific pollinations mainly between O. alpinum var. alpinum and O. pachyglossum, two species with very similar floral morphology. O. jacobinae, O. mexiae and O. subriparium are pollinated by bees. Wasps and bees carry one, two, three or several pollinaria in the mouthparts. O. mexiae, an endemic species in Viçosa, seems to present reproductive limitations, since its flowers are seldom visited. PMID:23505657

  2. Influence of catchment-scale military land use on stream physical and organic matter variables in small Southeaster Plains Catchments (USA)

    SciTech Connect

    Maloney, Kelly

    2005-01-01

    We conducted a 3-year study designed to examine the relationship between disturbance from military land use and stream physical and organic matter variables within 12 small (<5.5 km2) Southeastern Plains catchments at the Fort Benning Military Installation, Georgia, USA. Primary land-use categories were based on percentages of bare ground and road cover and nonforested land (grasslands, sparse vegetation, shrublands, fields) in catchments and natural catchments features, including soils (% sandy soils) and catchment size (area). We quantified stream flashiness (determined by slope of recession limbs of storm hydrographs), streambed instability (measured by relative changes in bed height over time), organic matter storage [coarse wood debris (CWD) relative abundance, benthic particulate organic matter (BPOM)] and stream-water dissolved organic carbon concentration (DOC). Stream flashiness was positively correlated with average storm magnitude and percent of the catchment with sandy soil, whereas streambed instability was related to percent of the catchment containing nonforested (disturbed) land. The proportions of in-stream CWD and sediment BPOM, and stream-water DOC were negatively related to the percent of bare ground and road cover in catchments. Collectively, our results suggest that the amount of catchment disturbance causing denuded vegetation and exposed, mobile soil is (1) a key terrestrial influence on stream geomorphology and hydrology and (2) a greater determinant of in-stream organic matter conditions than is natural geomorphic or topographic variation (catchment size, soil type) in these systems.

  3. Pass Over Southeastern Asia

    NASA Video Gallery

    This video over Southeastern Asia was taken by the crew of Expedition 29 aboard the International Space Station. This sequence of shots was taken on Oct. 7, 2011, from 12:41:10 to 12:50:46 GMT, on ...

  4. Southeastern Science Policy Colloquium

    SciTech Connect

    Humphries, F.

    1995-06-22

    This conference covers four main topics: (1) Southeastern Labor Market and its Impact on Corporate/Industry Development; (2) New Issues for Science and Technology in the Year 2000 and Beyond; (3) The Role of Academia in Developing the Labor Force of the Southeast; and (4) K-12 Education: Challenges for the 21st Century.

  5. Land use change and land degradation in southeastern Mediterranean Spain.

    PubMed

    Symeonakis, Elias; Calvo-Cases, Adolfo; Arnau-Rosalen, Eva

    2007-07-01

    The magnitude of the environmental and social consequences of soil erosion and land degradation in semiarid areas of the Mediterranean region has long been recognized and studied. This paper investigates the interrelationship between land use/cover (LULC) changes and land degradation using remotely sensed and ancillary data for southeastern Spain. The area of study, the Xaló River catchment situated in the north of the Alicante Province, has been subjected to a number of LULC changes during the second half of the 20th century such as agricultural abandonment, forest fires, and tourist development. Aerial photographs dating back to 1956 were used for the delineation of historic LULC types; Landsat ETM+ data were used for the analysis and mapping of current conditions. Two important indicators of land degradation, namely, susceptibility to surface runoff and soil erosion, were estimated for the two dates using easily parametrizable models. The comparison of 1956 to 2000 conditions shows an overall "recuperating" trend over the catchment and increased susceptibility to soil erosion only in 3% of the catchment area. The results also identify potential degradation hot-spots where mitigation measures should be taken to prevent further degradation. The readily implemented methodology, based on modest data requirements demonstrated by this study, is a useful tool for catchment to regional scale land use change and land degradation studies and strategic planning for environmental management. PMID:17530333

  6. Land Use Change and Land Degradation in Southeastern Mediterranean Spain

    NASA Astrophysics Data System (ADS)

    Symeonakis, Elias; Calvo-Cases, Adolfo; Arnau-Rosalen, Eva

    2007-07-01

    The magnitude of the environmental and social consequences of soil erosion and land degradation in semiarid areas of the Mediterranean region has long been recognized and studied. This paper investigates the interrelationship between land use/cover (LULC) changes and land degradation using remotely sensed and ancillary data for southeastern Spain. The area of study, the Xaló River catchment situated in the north of the Alicante Province, has been subjected to a number of LULC changes during the second half of the 20th century such as agricultural abandonment, forest fires, and tourist development. Aerial photographs dating back to 1956 were used for the delineation of historic LULC types; Landsat ETM+ data were used for the analysis and mapping of current conditions. Two important indicators of land degradation, namely, susceptibility to surface runoff and soil erosion, were estimated for the two dates using easily parametrizable models. The comparison of 1956 to 2000 conditions shows an overall “recuperating” trend over the catchment and increased susceptibility to soil erosion only in 3% of the catchment area. The results also identify potential degradation hot-spots where mitigation measures should be taken to prevent further degradation. The readily implemented methodology, based on modest data requirements demonstrated by this study, is a useful tool for catchment to regional scale land use change and land degradation studies and strategic planning for environmental management.

  7. A methodological comparison of catchment storages in mountainous catchments

    NASA Astrophysics Data System (ADS)

    Weiler, Markus; Staudinger, Maria; Stölzle, Michael; Seeger, Stefan; Seibert, Jan; Stahl, Kerstin

    2015-04-01

    One of the most important functions of catchments is the temporary storage of water, which directly influences runoff dynamics, rainfall-runoff transformation, partitioning of evaporation and runoff fluxes, and accessibility of water to plants. Generally, a large catchment storage is considered beneficial and in particular increases the transit times and hence the buffer functioning related to water quality. Many different methods have been developed to assess catchment storage, however, there are hardly any direct comparisons of several of these methods. One challenge is the definition of water storage, while some methods allow estimation of the entire water storage in a catchment, other methods quantify only the dynamic storage. In addition, most studies focused more on lowland catchments with rain-dominated runoff regimes and observed groundwater fluctuations. Furthermore, these studies often focus on one or two catchments, but do not consider the influence of different climates on the relevance of water storage in the catchment. We applied a range of different methods to assess catchment storage characteristics in 18 catchments in the Swiss Alps, ranging from 500 to 2000m of mean elevation and hence from rainfall- to snowmelt dominated runoff regimes. The first method use only discharge information during recession periods and with varying approaches to extract discharge and storage changes between high flow and low flow, the dynamic catchment storage can be derived. In the next methods the conceptual hydrological model HBV is calibrated to the runoff dynamics and the dynamic and total catchment storages of the different compartments are being evaluated. The last methods are based on stable water isotope data analysis. We use the model TRANSEP to derive the dynamic storage as well as the total water storage of the catchment based on the transit times using several years of fortnightly isotope data in streamflow. The results show that the derived catchment

  8. Catchment controls on solute export

    NASA Astrophysics Data System (ADS)

    Musolff, Andreas; Schmidt, Christian; Selle, Benny; Fleckenstein, Jan H.

    2015-12-01

    Dynamics of solute export from catchments can be classified in terms of chemostatic and chemodynamic export regimes by an analysis of concentration-discharge relationships. Previous studies hypothesized that distinct export regimes emerge from the presence of solute mass stores within the catchment and their connectivity to the stream. However, so far a direct link of solute export to identifiable catchment characteristics is missing. Here we investigate long-term time series of stream water quality and quantity of nine neighboring catchments in Central Germany ranging from relatively pristine mountain catchments to agriculturally dominated lowland catchments, spanning large gradients in land use, geology, and climatic conditions. Given the strong collinearity of catchment characteristics we used partial least square regression analysis to quantify the predictive power of these characteristics for median concentrations and the metrics of export regime. We can show that median concentrations and metrics of the export regimes of major ions and nutrients can indeed be inferred from catchment characteristics. Strongest predictors for median concentrations were the share of arable land, discharge per area, runoff coefficient and available water capacity in the root zone of the catchments. The available water capacity in the root zone, the share of arable land being artificially drained and the topographic gradient were found to be the most relevant predictors for the metrics of export regime. These catchment characteristics can represent the size of solute mass store such as the fraction of arable land being a measure for the store of nitrate. On the other hand, catchment characteristics can be a measure for the connectivity of these solute stores to the stream such as the fraction of tile drained land in the catchments. This study demonstrates the potential of data-driven, top down analyses using simple metrics to classify and better understand dominant controls of

  9. Profiles of sex steroids, fecundity, and spawning of the curimatã-pacu Prochilodus argenteus in the São Francisco River, downstream from the Três Marias Dam, Southeastern Brazil.

    PubMed

    Arantes, Fábio P; Santos, Helio B; Rizzo, Elizete; Sato, Yoshimi; Bazzoli, Nilo

    2010-04-01

    The present study evaluated for the first time sex steroid profiles and fecundity in females of Prochilodus argenteus from two sections of the São Francisco River Brazil, downstream from the Três Marias Dam, which influences characteristics of their water habitat. The model species in the study, P. argenteus, is an important commercial and recreational species in Brazil. In the region closest to the dam (section 1), females did not reach final oocyte maturation, failed to spawn, and displayed lesser circulating concentrations of testosterone, 17(-hydroxyprogesterone (17(-P) and 17beta-estradiol (E2) than those farther downstream of the dam (section 2). The endocrine and fecundity deficiencies probably are attributed to lower water temperature and oxygen concentration in (section 1). The follicular atresia rate in the region closest to the dam (26%) was greater than those fish captured farther downstream of the dam (13%), after the Abaeté River (section 2). Variations in testosterone, E2 and 17(-P concentrations in section 2, followed gonadal maturation which are typical features of species which have seasonal reproduction, group-synchronous oocyte development, and are single batch spawners such as P. argenteus. Results document the first evidence of endocrine and reproductive dysfunctions caused by inadequate water conditions in a wild population of the migratory species P. argenteus in the São Francisco River, downstream from the Três Marias dam. PMID:19683404

  10. Water balance complexities in ephemeral catchments with different land uses: Insights from monitoring and distributed hydrologic modeling

    NASA Astrophysics Data System (ADS)

    Dean, J. F.; Camporese, M.; Webb, J. A.; Grover, S. P.; Dresel, P. E.; Daly, E.

    2016-06-01

    Although ephemeral catchments are widespread in arid and semiarid climates, the relationship of their water balance with climate, geology, topography, and land cover is poorly known. Here we use 4 years (2011-2014) of rainfall, streamflow, and groundwater level measurements to estimate the water balance components in two adjacent ephemeral catchments in south-eastern Australia, with one catchment planted with young eucalypts and the other dedicated to grazing pasture. To corroborate the interpretation of the observations, the physically based hydrological model CATHY was calibrated and validated against the data in the two catchments. The estimated water balances showed that despite a significant decline in groundwater level and greater evapotranspiration in the eucalypt catchment (104-119% of rainfall) compared with the pasture catchment (95-104% of rainfall), streamflow consistently accounted for 1-4% of rainfall in both catchments for the entire study period. Streamflow in the two catchments was mostly driven by the rainfall regime, particularly rainfall frequency (i.e., the number of rain days per year), while the downslope orientation of the plantation furrows also promoted runoff. With minimum calibration, the model was able to adequately reproduce the periods of flow in both catchments in all years. Although streamflow and groundwater levels were better reproduced in the pasture than in the plantation, model-computed water balance terms confirmed the estimates from the observations in both catchments. Overall, the interplay of climate, topography, and geology seems to overshadow the effect of land use in the study catchments, indicating that the management of ephemeral catchments remains highly challenging.

  11. Moments of catchment storm area

    NASA Technical Reports Server (NTRS)

    Eagleson, P. S.; Wang, Q.

    1985-01-01

    The portion of a catchment covered by a stationary rainstorm is modeled by the common area of two overlapping circles. Given that rain occurs within the catchment and conditioned by fixed storm and catchment sizes, the first two moments of the distribution of the common area are derived from purely geometrical considerations. The variance of the wetted fraction is shown to peak when the catchment size is equal to the size of the predominant storm. The conditioning on storm size is removed by assuming a probability distribution based upon the observed fractal behavior of cloud and rainstorm areas.

  12. Lessons learned from integrated hydrological modeling of ephemeral catchments with different land uses

    NASA Astrophysics Data System (ADS)

    Camporese, Matteo; Dean, Joshua; Daly, Edoardo

    2016-04-01

    Land use, in particular tree cover, has a strong influence on evapotranspiration (ET) and thus a large effect on the water budget of ephemeral catchments in arid and semi-arid climates. Unfortunately, the dearth of medium to long-term experimental observations in such areas limits the understanding of the interplay between catchment geology, land use, and climate in driving catchment water balance. Here we use four years (2011-2014) of rainfall, streamflow, and groundwater level measurements to estimate the water balance components in two small, adjacent, ephemeral catchments in a semi-arid region of south-eastern Australia; one catchment was predominantly covered with a eucalypt plantation established in July 2008 and the other was dedicated to grazing pasture. The integrated hydrological model CATHY (CATchment HYdrology) was calibrated against the data in the two catchments using streamflow and groundwater level observations in 2011; the data in the following years (2012-2014) were used for the model validation. The model was able to adequately reproduce the periods of flow in both catchments in all years, although streamflow and groundwater levels were better reproduced in the pasture than in the plantation. This can partly be attributed to the root growth of the trees, which is difficult to estimate; the declining water storage in the eucalypt catchment could only be obtained when including a simple model of root growth dynamics. Other sources of uncertainty could be due to an imperfect description of the surface topography and bedrock geology, which prevent us from accurately reproducing the effects of the tree furrows and subsurface wetness connectivity. The water balances estimated from both data and model showed a significant increase in ET in the eucalypt plantation catchment at the expense of groundwater storage: ET accounted for 95-104% of rainfall in the pasture catchment and 104-119% in the eucalypt catchment across the four years studied. However, the

  13. Leaf breakdown in streams differing in catchment land use

    USGS Publications Warehouse

    Paul, M.J.; Meyer, J.L.; Couch, C.A.

    2006-01-01

    1. The impact of changes in land use on stream ecosystem function is poorly understood. We studied leaf breakdown, a fundamental process of stream ecosystems, in streams that represent a range of catchment land use in the Piedmont physiographic province of the south-eastern United States. 2. We placed bags of chalk maple (Acer barbatum) leaves in similar-sized streams in 12 catchments of differing dominant land use: four forested, three agricultural, two suburban and three urban catchments. We measured leaf mass, invertebrate abundance and fungal biomass in leaf bags over time. 3. Leaves decayed significantly faster in agricultural (0.0465 day-1) and urban (0.0474 day-1) streams than in suburban (0.0173 day-1) and forested (0.0100 day-1) streams. Additionally, breakdown rates in the agricultural and urban streams were among the fastest reported for deciduous leaves in any stream. Nutrient concentrations in agricultural streams were significantly higher than in any other land-use type. Fungal biomass associated with leaves was significantly lower in urban streams; while shredder abundance in leaf bags was significantly higher in forested and agricultural streams than in suburban and urban streams. Storm runoff was significantly higher in urban and suburban catchments that had higher impervious surface cover than forested or agricultural catchments. 4. We propose that processes accelerating leaf breakdown in agricultural and urban streams were not the same: faster breakdown in agricultural streams was due to increased biological activity as a result of nutrient enrichment, whereas faster breakdown in urban streams was a result of physical fragmentation resulting from higher storm runoff. ?? 2006 The Authors.

  14. Patterns of genetic diversity in southern and southeastern Araucaria angustifolia (Bert.) O. Kuntze relict populations

    PubMed Central

    2009-01-01

    Habitat fragmentation and a decrease in population size may lead to a loss in population genetic diversity. For the first time, the reduction in genetic diversity in the northernmost limit of natural occurence (southeastern Brazil) of Araucaria angustifolia in comparison with populations in the main area of the species continuous natural distribution (southern Brazil), was tested. The 673 AFLPs markers revealed a high level of genetic diversity for the species (Ht = 0.27), despite anthropogenic influence throughout the last century, and a decrease of H in isolated populations of southeastern Brazil (H = 0.16), thereby indicating the tendency for higher genetic diversity in remnant populations of continuous forests in southern Brazil, when compared to natural isolated populations in the southeastern region. A strong differentiation among southern and southeastern populations was detected (AMOVA variance ranged from 10%-15%). From Bayesian analysis, it is suggested that the nine populations tested form five “genetic clusters” (K = 5). Five of these populations, located in the northernmost limit of distribution of the species, represent three “genetic clusters”. These results are in agreement with the pattern of geographic distribution of the studied populations. PMID:21637518

  15. Prevalence and risk factors for giardiasis and soil-transmitted helminthiasis in three municipalities of Southeastern Minas Gerais State, Brazil: risk factors for giardiasis and soil-transmitted helminthiasis.

    PubMed

    Pinheiro, Izabella de Oliveira; de Castro, Milton Ferreira; Mitterofhe, Adalberto; Pires, Flávia Alves Condé; Abramo, Clarice; Ribeiro, Luiz Cláudio; Tibiriçá, Sandra Helena Cerrato; Coimbra, Elaine Soares

    2011-05-01

    Giardiasis and soil-transmitted helminthiasis (STH) are parasitic diseases that are among the major health concerns observed in economically disadvantaged populations of developing countries, and have clear social and environmental bases. In Brazil, there is a lack of epidemiologic data concerning these infections in the study area, whose inhabitants have plenty of access to health care services, including good dwelling and adequate sanitary conditions. In this survey we investigated the risk factors for giardiasis and STH in three municipalities with good sanitation, situated in Minas Gerais state, Brazil. A cross-sectional survey was conducted in the municipalities of Piau, Coronel Pacheco and Goianá, in both urban and rural areas. The fieldwork consisted of a questionnaire and the examination of 2,367 stool samples using the Hoffmann, Pons and Janer method. Of all individuals from the population sample, 6.1% were found infected with the parasitic diseases included in this work. Hookworm infection was the most prevalent disease, followed by giardiasis, trichuriasis and ascariasis. Infection was more prevalent in males (8.1%, p < 0.001; odds ratio [OR] = 1.975) and in individuals living in rural areas (8.6%, p = 0.003; OR = 1.693). Multivariate analysis showed that variables such as inadequate sewage discharge (p < 0.001), drinking of unsafe water (p < 0.001), lack of sanitary infrastructure (p = 0.015), and host sex (p < 0.001) were the risk factors more strongly associated with infection status (95% confidence interval [CI]). In this study we demonstrate that giardiasis and STH still persist, infecting people who have good housing conditions and free access to public health care and education. PMID:21243507

  16. Hydrological Catchment Similarity Assessment in Geum River Catchments, Korea

    NASA Astrophysics Data System (ADS)

    Ko, Ara; Park, Kisoon; Lee, Hyosang

    2013-04-01

    Similarity measure of catchments is essential for regionalization studies, which provide in depth analysis in hydrological response and flood estimations at ungauged catchments. However, this similarity measure is often biased to the selected catchments and is notclearly explained in hydrological sense. This study applied a type of hydrological similarity distance measure-Flood Estimation Handbook to 25 Geum river catchments, Korea. Three Catchment Characteristics, Area (A)-Annual precipitation (SAAR)-SCS Curve Number (CN), are used in Euclidian distance measures. Furthermore, six index of Flow Duration Curve (ILow:Q275/Q185, IDrought:Q355/Q185, IFlood:Qmax/Q185, IAbundant:Q95/Q185, IFloodDuration:Q10/Q355 and IRiverRegime:Qmax/Qmin) are applied to clustering analysis of SPSS. The catchments' grouping of hydrological similarity measures suggests three groups: H1 (Cheongseong, Gidae, Bukil, Oksan, Seockhwa, Habgang and Sangyeogyo), H2 (Cheongju, Guryong, Ugon, Boksu, Useong and Seokdong) and H3 (Muju, Yangganggyo and YongdamDam). The four catchments (Cheoncheon, Donghyang, DaecheongDam and Indong) are not grouped in this study. The clustering analysis of FDC provides four Groups; CFDC1 (Muju, YongdamDam, Yangganggyo, DaecheongDam, Cheongseong, Gidae, Seokhwa, Bukil, Habgang, Cheongju, Oksan, Yuseong and Guryong), CFDC2 (Cheoncheon, Donghyang, Boksu, Indong, Nonsan, Seokdong, Ugon, Simcheon, Useong and Sangyeogyo), CFDC3 (Songcheon) and CFDC4 (Tanbu). The six catchments (out of seven) of H1 are grouped in CFDC1, while Sangyeogyo is grouped in CFDC2. The four catchments (out of six) of H2 are also grouped in CFDC2, while Cheongju and Guryong are grouped in CFDC1. The catchments of H3 are categorized in CFDC1. The authors examine the results (H1, H2 and H3) of similarity measure based on catchment physical descriptors with results (CFDC1 and CFDC2) of clustering based on catchment hydrological response. The results of hydrological similarity measures are supported by

  17. Sulfur Mass Balances of Forested Catchments: Improving Predictions of Stream Sulfate Concentrations Through Better Representation of Soil Storage and Release

    NASA Astrophysics Data System (ADS)

    Scanlon, T. M.; Rice, K. C.; Riscassi, A.; Cosby, B. J., Jr.

    2015-12-01

    Sulfur dioxide (SO2) emissions in the eastern United States have declined by more than 80% since 1970, when the Clean Air Act first established limits on emissions from stationary and mobile sources. In many areas throughout the northeastern U.S., the resulting declines in sulfate (SO42-) deposition have been accompanied by declines in stream SO42- concentrations. In the southeastern U.S., however, declines in stream SO42- concentrations have not been observed on a widespread basis. In fact, SO42- concentrations continue to increase in many southeastern streams despite decades of declining deposition. This difference in behavior between northeastern and southeastern streams, owing to the distinct geological histories of their catchment soils, was anticipated by the Direct/Delayed Response Project initiated by the U.S. EPA during the early 1980s. At that time, understanding of how catchments store and release SO42- was mostly grounded in theory. Now, with the accumulation of long-term stream chemistry and hydrological datasets in forested catchments, we may develop an empirical basis for characterizing catchment storage and release of SO42-. In particular, are whole-catchment isotherms that described the partitioning between adsorbed and dissolved SO42- (1) linear or non-linear and (2) reversible or irreversible? How do these isotherms vary on a geographical basis? We apply mass balance combined with a simple theoretical framework to infer whole-catchment SO42- isotherms in Virginia and New England. Knowledge of this key soil geochemical property is needed to improve predictions of how catchments will store and export SO42- under changing levels of atmospheric deposition.

  18. Environmental care in agricultural catchments: Toward the communicative catchment

    NASA Astrophysics Data System (ADS)

    Martin, Peter

    1991-11-01

    Substantial land degradation of agricultural catchments in Australia has resulted from the importation of European farming methods and the large-scale clearing of land. Rural communities are now being encouraged by government to take responsibility for environmental care. The importance of community involvement is supported by the view that environmental problems are a function of interactions between people and their environment. It is suggested that the commonly held view that community groups cannot care for their resources is due to inappropriate social institutions rather that any inherent disability in people. The communicative catchment is developed as a vision for environmental care into the future. This concept emerges from a critique of resource management through the catchment metaphors of the reduced, mechanical, and the complex, evolving catchment, which reflect the development of systemic and people-centered approaches to environmental care. The communicative catchment is one where both community and resource managers participate collaboratively in environmental care. A methodology based on action research and systemic thinking (systemic action research) is proposed as a way of moving towards the communicative catchment of the future. Action research is a way of taking action in organizations and communities that is participative and informed by theory, while systemic thinking takes into account the interconnections and relationships between social and natural worlds. The proposed vision, methodology, and practical operating principles stem from involvement in an action research project looking at extension strategies for the implementation of total catchment management in the Hunter Valley, New South Wales.

  19. Improving Distributed Runoff Prediction in Urbanized Catchments with Remote Sensing based Estimates of Impervious Surface Cover

    PubMed Central

    Chormanski, Jaroslaw; Van de Voorde, Tim; De Roeck, Tim; Batelaan, Okke; Canters, Frank

    2008-01-01

    The amount and intensity of runoff on catchment scale are strongly determined by the presence of impervious land-cover types, which are the predominant cover types in urbanized areas. This paper examines the impact of different methods for estimating impervious surface cover on the prediction of peak discharges, as determined by a fully distributed rainfall-runoff model (WetSpa), for the upper part of the Woluwe River catchment in the southeastern part of Brussels. The study shows that detailed information on the spatial distribution of impervious surfaces, as obtained from remotely sensed data, produces substantially different estimates of peak discharges than traditional approaches based on expert judgment of average imperviousness for different types of urban land use. The study also demonstrates that sub-pixel estimation of imperviousness may be a useful alternative for more expensive high-resolution mapping for rainfall-runoff modelling at catchment scale.

  20. The catchment based approach using catchment system engineering

    NASA Astrophysics Data System (ADS)

    Jonczyk, Jennine; Quinn, Paul; Barber, Nicholas; Wilkinson, Mark

    2015-04-01

    The catchment based approach (CaBa) has been championed as a potential mechanism for delivery of environmental directives such as the Water Framework Directive in the UK. However, since its launch in 2013, there has been only limited progress towards achieving sustainable, holistic management, with only a few of examples of good practice ( e.g. from the Tyne Rivers trust). Common issues with developing catchment plans over a national scale include limited data and resources to identify issues and source of those issues, how to systematically identify suitable locations for measures or suites of measures that will have the biggest downstream impact and how to overcome barriers for implementing solutions. Catchment System Engineering (CSE) is an interventionist approach to altering the catchment scale runoff regime through the manipulation of hydrological flow pathways throughout the catchment. A significant component of the runoff generation can be managed by targeting hydrological flow pathways at source, such as overland flow, field drain and ditch function, greatly reducing erosive soil losses. Coupled with management of farm nutrients at source, many runoff attenuation features or measures can be co-located to achieve benefits for water quality and biodiversity. A catchment, community-led mitigation measures plan using the CSE approach will be presented from a catchment in Northumberland, Northern England that demonstrate a generic framework for identification of multi-purpose features that slow, store and filter runoff at strategic locations in the landscape. Measures include within-field barriers, edge of field traps and within-ditch measures. Progress on the implementation of measures will be reported alongside potential impacts on the runoff regime at both local and catchment scale and costs.

  1. Alexander Archipelago, Southeastern Alaska

    NASA Technical Reports Server (NTRS)

    2002-01-01

    West of British Columbia, Canada, and south of the Yukon Territory, the southeastern coastline of Alaska trails off into the islands of the Alexander Archipelago. The area is rugged and contains many long, U-shaped, glaciated valleys, many of which terminate at tidewater. The Alexander Archipelago is home to Glacier Bay National Park. The large bay that has two forks on its northern end is Glacier Bay itself. The eastern fork is Muir inlet, into which runs the Muir glacier, named for the famous Scottish-born naturalist John Muir. Glacier Bay opens up into the Icy Strait. The large, solid white area to the west is Brady Icefield, which terminates at the southern end in Brady's Glacier. To locate more interesting features from Glacier Bay National Park, take a look at the park service map. As recently as two hundred years ago, a massive ice field extended into Icy Strait and filled the Glacier Bay. Since that time, the area has experienced rapid deglaciation, with many large glaciers retreating 40, 60, even 80 km. While temperatures have increased in the region, it is still unclear whether the rapid recession is part of the natural cycle of tidewater glaciers or is an indicator of longer-term climate change. For more on Glacier Bay and climate change, read an online paper by Dr. Dorothy Hall, a MODIS Associate Science Team Member. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  2. Lespesia melloi sp. nov. (Diptera: Tachinidae) from Brazil, a Parasitoid of Xanthopastis timais (Lepidoptera: Noctuidae)

    PubMed Central

    Gil-Santana, Hélcio R.; Nihei, Silvio Shigueo; Nunez, Enio

    2014-01-01

    A new species of the New World genus Lespesia, Lespesia melloi sp. nov. (Diptera: Tachinidae), is described from southeastern Brazil. The species is reported here as a parasitoid of Xanthopastis timais (Cramer, 1782) (Lepidoptera: Noctuidae). The caterpillars of this noctuid feed on leaves and bulbs of amaryllis (Amaryllidaceae) in Brazil. PMID:25368065

  3. Lespesia melloi sp. nov. (Diptera: Tachinidae) from Brazil, a parasitoid of Xanthopastis timais(Lepidoptera: Noctuidae).

    PubMed

    Gil-Santana, Hélcio R; Nihei, Silvio Shigueo; Nunez, Enio

    2014-01-01

    A new species of the New World genus Lespesia, Lespesia melloi SP NOV: (Diptera: Tachinidae), is described from southeastern Brazil. The species is reported here as a parasitoid of Xanthopastis timais (Cramer, 1782) (Lepidoptera: Noctuidae). The caterpillars of this noctuid feed on leaves and bulbs of amaryllis (Amaryllidaceae) in Brazil. PMID:25368065

  4. Differentiating causes for erosion at the catchment scale: do soil conservation measures mitigate weather dynamics?

    NASA Astrophysics Data System (ADS)

    Barneveld, Robert; Greipsland, Inga

    2016-04-01

    The efficacy of most measures to control soil loss is well established at the field or plot scale. Less well documented are the changes in hydrological behaviour and sediment production at the scale of the (small) catchment. In Norway, incentives to reduce tillage have been in place for over decades. However, even long time (20 years) discharge monitoring of a series of small catchments does not show a clear effect of the application of conservation measures. This research hypothesizes that the effect of weather conditions for a 4.2 km2 catchment in southeastern Norway outweighs the effect of conservation measures in the time series on runoff and sediment load. To test this, it was assumed that trends and changes in soil loss E over time are the product of an agromic index C, precipitation P and rainfall erosivity R. The values of C were calculated based on extensive farm records, covering every tillage operation for every field in the catchment for the period of investigation. Runoff and sediment load records were used to parameterise and test different correlative models. In order to quantify the effect of topography on the degree to which conservations measures reduce soil loss at catchment level, a spatially distributed connectivity index was calculated and multiplied with C. Calculations were carried out for a 10 year period, in monthly time steps. The following statistical models proved the most promising to correlate sediment load to precipitation and agronomic practice. Et=a \\cdot Ptb \\cdot Pt-1c \\cdot Ctd Et=a \\cdot Rtb \\cdot Pt-1c \\cdot Ctd where Pt-1c, the precipition in the prior month, is a proxy indicator for antecedent moisture conditions. The results show that precipitation dynamics outweigh the effect of soil conservation measures for this typical agricultural catchment. It also shows that the inclusion of a hydrological connectivity index improves the quantification of the effect of soil conservation measures on the catchment scale.

  5. Effects of land cover change on evapotranspiration and streamflow of small catchments in the Upper Xingu River Basin, Central Brazi

    NASA Astrophysics Data System (ADS)

    Costa, M. H.; Dias, L. C. P.; Macedo, M.; Coe, M. T.; Neill, C.

    2015-12-01

    This study assess the influence of land cover changes on evapotranspiration and streamflow in small catchments in the Upper Xingu River Basin (Mato Grosso state, Brazil). Streamflow was measured in catchments with uniform land use for September 1, 2008 to August 31, 2010. We used models to simulate evapotranspiration and streamflow for the four most common land cover types found in the Upper Xingu: tropical forest, cerrado (savanna), pasture, and soybean croplands. We used INLAND to perform single point simulations considering tropical rainforest, cerrado and pasturelands, and AgroIBIS for croplands. Converting natural vegetation to agriculture substantially modifies evapotranspiration and streamflow in small catchments. Measured mean streamflow in soy catchments was about three times greater than that of forest catchments, while the mean annual amplitude of flow in soy catchments was more than twice that of forest catchments. Simulated mean annual evapotranspiration was 39% lower in agricultural ecosystems (pasture and soybean cropland) than in natural ecosystems (tropical rainforest and cerrado). Observed and simulated mean annual streamflows in agricultural ecosystems were more than 100% higher than in natural ecosystems. The accuracy of the simulations is improved by using field-measured soil hydraulic properties. The inclusion of local measurements of key soil parameters is likely to improve hydrological simulations in other tropical regions.

  6. Effects of land cover change on evapotranspiration and streamflow of small catchments in the Upper Xingu River Basin, Central Brazi

    NASA Astrophysics Data System (ADS)

    Costa, M. H.; Dias, L. C. P.; Macedo, M.; Coe, M. T.; Neill, C.

    2014-12-01

    This study assess the influence of land cover changes on evapotranspiration and streamflow in small catchments in the Upper Xingu River Basin (Mato Grosso state, Brazil). Streamflow was measured in catchments with uniform land use for September 1, 2008 to August 31, 2010. We used models to simulate evapotranspiration and streamflow for the four most common land cover types found in the Upper Xingu: tropical forest, cerrado (savanna), pasture, and soybean croplands. We used INLAND to perform single point simulations considering tropical rainforest, cerrado and pasturelands, and AgroIBIS for croplands. Converting natural vegetation to agriculture substantially modifies evapotranspiration and streamflow in small catchments. Measured mean streamflow in soy catchments was about three times greater than that of forest catchments, while the mean annual amplitude of flow in soy catchments was more than twice that of forest catchments. Simulated mean annual evapotranspiration was 39% lower in agricultural ecosystems (pasture and soybean cropland) than in natural ecosystems (tropical rainforest and cerrado). Observed and simulated mean annual streamflows in agricultural ecosystems were more than 100% higher than in natural ecosystems. The accuracy of the simulations is improved by using field-measured soil hydraulic properties. The inclusion of local measurements of key soil parameters is likely to improve hydrological simulations in other tropical regions.

  7. Age and weathering rate of sediments in small catchments: The role of hillslope erosion

    NASA Astrophysics Data System (ADS)

    Dosseto, Anthony; Buss, Heather L.; Chabaux, François

    2014-05-01

    Uranium-series (U-series) isotopes in river material can be used to determine quantitative time constraints on the transfer of erosion products from source to sink. In this study, we investigate the U-series isotope composition of river-borne material in small catchments of Puerto Rico and southeastern Australia in order to improve our understanding of (i) the controls on the U-series isotope composition of river-borne material and (ii) how erosion products acquire their geochemical characteristics. In both regions, thorium isotopes track the origin of sediment and dissolved loads. Stream solutes are mainly derived from the deepest part of the weathering profile, whereas stream sediments originate from much shallower horizons, even in landslide-dominated Puerto Rican catchments. This suggests that in environments where thick weathering profiles have developed, solutes and sediments have distinct origins.

  8. Coevolution of volcanic catchments in Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, Takeo; Troch, Peter A.

    2016-03-01

    Present-day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment coevolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma) in Japan. We derived indices of landscape properties (drainage density and slope-area relationship) as well as hydrological response (annual water balance, baseflow index, and flow-duration curves) and examined their relation with catchment age and climate (through the aridity index). We found a significant correlation between drainage density and baseflow index with age, but not with climate. The intra-annual flow variability was also significantly related to catchments age. Younger catchments tended to have lower peak flows and higher low flows, while older catchments exhibited more flashy runoff. The decrease in baseflow with catchment age is consistent with the existing hypothesis that in volcanic landscapes the major flow pathways change over time from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in a set of similar, but younger volcanic catchments in the Oregon Cascades, in which drainage density increased with age. In that case, older catchments were thought to show more landscape incision due to increasing near-surface lateral flow paths. Our results suggests two competing hypotheses on the evolution of drainage density in mature catchments. One is that as catchments continue to age, the hydrologically active channels retreat

  9. Adaptations of a physical-based hydrological model for alpine catchments. Application to the upper Durance catchment.

    NASA Astrophysics Data System (ADS)

    Lafaysse, Matthieu; Hingray, Benoit

    2010-05-01

    The impact of global change on water resources is expected to be especially pronounced in mountainous areas. Future hydrological scenarios required for impact studies are classically simulated with hydrological models from future meteorological scenarios based on GCMs outputs. Future hydrological regimes of French rivers were estimated following this methodology by Boé et al. (2009) with the physical-based hydrological model SAFRAN-ISBA-MODCOU (SIM), developed by Météo-France. Scenarios obtained for the Alps seem however not very reliable due to the poor performance achieved by the model for the present climate over this region. This work presents possible improvements of SIM for a more relevant simulation of alpine catchments hydrological behavior. Results obtained for the upper Durance catchment (3580 km2) are given for illustration. This catchment is located in Southern French Alps. Its outlet is the Serre-Ponçon lake, a large dam operated for hydropower production, with a key role for water supply in southeastern France. With altitudes ranging from 700 to 4100 meters, the catchment presents highly seasonal flows: minimum and maximum discharges are observed in winter and spring respectively due to snow accumulation and melt, low flows are sustained by glacier melt in late summer (39 km2 are covered by glaciers), major floods can be observed in fall due to large liquid precipitation amounts. Two main limitations of SIM were identified for this catchment. First the 8km-side grid discretization gives a bad representation of the spatial variability of hydrological processes induced by elevation and orientation. Then, low flows are not well represented because the model doesn't include deep storage in aquifers nor ice melt from glaciers. We modified SIM accordingly. For the first point, we applied a discretization based on topography : we divided the catchment in 9 sub-catchments and further 300 meters elevation bands. The vertical variability of meteorological

  10. SPECIES PROFILE: SOUTHEASTERN MYOTIS (MYOTIS AUSTRORIPARIUS) ON MILITARY INSTALLATIONS IN THE SOUTHEASTERN UNITED STATES

    EPA Science Inventory

    The southeastern myotis (Myotis austroriparius) is a medium-sized bat with grayish-brown, woolly fur. This species primarily is found in the southeastern United States. Its range extends from southeastern North Carolina south to peninsular Florida, west to eastern Texas and Oklah...

  11. How tritium illuminates catchment structure

    NASA Astrophysics Data System (ADS)

    Stewart, M.; Morgenstern, U.; McDonnell, J.

    2012-04-01

    Streams contain water which has taken widely-varying times to pass through catchments, and the distribution of ages is likely to change with the flow. Part of the water has 'runoff' straight to the stream with little delay, other parts are more delayed and some has taken years (in some cases decades) to traverse the deeper regolith or bedrock of the catchment. This work aims to establish the significance of the last component, which is important because it can cause catchments to have long memories of contaminant inputs (e.g. nitrate). Results of tritium studies on streams world-wide were accessed from the scientific literature. Most of the studies assumed that there were just two age-components present in the streams (i.e. young and old). The mean ages and proportions of the components were found by fitting simulations to tritium data. It was found that the old component in streams was substantial (average was 50% of the annual runoff) and had considerable age (average mean age was 10 years) (Stewart et al., 2010). Use of oxygen-18 or chloride variations to estimate streamflow mean age usually does not reveal the age or size of this old component, because these methods cannot detect water older than about four years. Consequently, the use of tritium has shown that substantial parts of streamflow in headwater catchments are older than expected, and that deep groundwater plays an active and sometimes even a dominant role in runoff generation. Difficulties with interpretation of tritium in streams in recent years due to interference from tritium due to nuclear weapons testing are becoming less serious, because very accurate tritium measurements can be made and there is now little bomb-tritium remaining in the atmosphere. Mean ages can often be estimated from single tritium measurements in the Southern Hemisphere, because there was much less bomb-tritium in the atmosphere. This may also be possible for some locations in the Northern Hemisphere. Age determination on

  12. Very long hillslope transport timescales determined from uranium-series isotopes in river sediments from a large, tectonically stable catchment

    NASA Astrophysics Data System (ADS)

    Suresh, P. O.; Dosseto, A.; Hesse, P. P.; Handley, H. K.

    2014-10-01

    The uranium-series isotopic compositions of soils and sediments evolve in response to time and weathering conditions. Therefore, these isotopes can be used to constrain the timescales of river sediment transport. Catchment evolution depends on the sediment dynamic timescales, on which erosion imparts a major control. Erosion rates in tectonically stable catchments are expected to be lower than those in tectonically active catchments, implying longer sediment residence times in tectonically stable catchments. Mineralogical, elemental and isotopic data are presented for modern channel sediments, alluvial and colluvial deposits from the Murrumbidgee River, a large catchment in the passive margin highlands of south-eastern Australia and three of its tributaries from the headwaters to the alluvial plain. Low variability in Si-based Weathering Index indicates that there is little chemical weathering occurring in the Murrumbidgee River during sediment transport. However, quartz content increases and plagioclase content decreases downstream, indicating progressive mineralogical sorting and/or physical comminution with increasing transport distance. U-series isotopic ratios in the Murrumbidgee River trunk stream sediments show no systematic downstream variation. The weathering ages of sediments within the catchment were determined using a loss-gain model of U-series isotopes. Modern sediments from a headwater tributary, the Bredbo River at Frogs Hollow, have a weathering age of 76 ± 30 kyr but all other modern channel sediments from the length of the Murrumbidgee River and its main tributaries have weathering ages ∼400 ± 180 kyr. The two headwater colluvial deposits have weathering ages of 57 ± 13 and 47 ± 11 kyr, respectively. All the alluvial deposits have weathering ages similar to those of modern sediments. No downstream trend in weathering age is observed. Together with the soil residence time of up to 30 kyr for ridge-top soils at Frogs Hollow in the upper

  13. Land-use-driven stream warming in southeastern Amazonia.

    PubMed

    Macedo, Marcia N; Coe, Michael T; DeFries, Ruth; Uriarte, Maria; Brando, Paulo M; Neill, Christopher; Walker, Wayne S

    2013-06-01

    Large-scale cattle and crop production are the primary drivers of deforestation in the Amazon today. Such land-use changes can degrade stream ecosystems by reducing connectivity, changing light and nutrient inputs, and altering the quantity and quality of streamwater. This study integrates field data from 12 catchments with satellite-derived information for the 176,000 km(2) upper Xingu watershed (Mato Grosso, Brazil). We quantify recent land-use transitions and evaluate the influence of land management on streamwater temperature, an important determinant of habitat quality in small streams. By 2010, over 40 per cent of catchments outside protected areas were dominated (greater than 60% of area) by agriculture, with an estimated 10,000 impoundments in the upper Xingu. Streams in pasture and soya bean watersheds were significantly warmer than those in forested watersheds, with average daily maxima over 4°C higher in pasture and 3°C higher in soya bean. The upstream density of impoundments and riparian forest cover accounted for 43 per cent of the variation in temperature. Scaling up, our model suggests that management practices associated with recent agricultural expansion may have already increased headwater stream temperatures across the Xingu. Although increased temperatures could negatively impact stream biota, conserving or restoring riparian buffers could reduce predicted warming by as much as fivefold. PMID:23610164

  14. Land-use-driven stream warming in southeastern Amazonia

    PubMed Central

    Macedo, Marcia N.; Coe, Michael T.; DeFries, Ruth; Uriarte, Maria; Brando, Paulo M.; Neill, Christopher; Walker, Wayne S.

    2013-01-01

    Large-scale cattle and crop production are the primary drivers of deforestation in the Amazon today. Such land-use changes can degrade stream ecosystems by reducing connectivity, changing light and nutrient inputs, and altering the quantity and quality of streamwater. This study integrates field data from 12 catchments with satellite-derived information for the 176 000 km2 upper Xingu watershed (Mato Grosso, Brazil). We quantify recent land-use transitions and evaluate the influence of land management on streamwater temperature, an important determinant of habitat quality in small streams. By 2010, over 40 per cent of catchments outside protected areas were dominated (greater than 60% of area) by agriculture, with an estimated 10 000 impoundments in the upper Xingu. Streams in pasture and soya bean watersheds were significantly warmer than those in forested watersheds, with average daily maxima over 4°C higher in pasture and 3°C higher in soya bean. The upstream density of impoundments and riparian forest cover accounted for 43 per cent of the variation in temperature. Scaling up, our model suggests that management practices associated with recent agricultural expansion may have already increased headwater stream temperatures across the Xingu. Although increased temperatures could negatively impact stream biota, conserving or restoring riparian buffers could reduce predicted warming by as much as fivefold. PMID:23610164

  15. A Regional Modeling Framework of Phosphorus Sources and Transport in Streams of the Southeastern United States

    USGS Publications Warehouse

    Garcia, A.M.; Hoos, A.B.; Terziotti, S.

    2011-01-01

    We applied the SPARROW model to estimate phosphorus transport from catchments to stream reaches and subsequent delivery to major receiving water bodies in the Southeastern United States (U.S.). We show that six source variables and five land-to-water transport variables are significant (p<0.05) in explaining 67% of the variability in long-term log-transformed mean annual phosphorus yields. Three land-to-water variables are a subset of landscape characteristics that have been used as transport factors in phosphorus indices developed by state agencies and are identified through experimental research as influencing land-to-water phosphorus transport at field and plot scales. Two land-to-water variables - soil organic matter and soil pH - are associated with phosphorus sorption, a significant finding given that most state-developed phosphorus indices do not explicitly contain variables for sorption processes. Our findings for Southeastern U.S. streams emphasize the importance of accounting for phosphorus present in the soil profile to predict attainable instream water quality. Regional estimates of phosphorus associated with soil-parent rock were highly significant in explaining instream phosphorus yield variability. Model predictions associate 31% of phosphorus delivered to receiving water bodies to geology and the highest total phosphorus yields in the Southeast were catchments with already high background levels that have been impacted by human activity. ?? 2011 American Water Resources Association. This article is a US Government work and is in the public domain in the USA.

  16. View of southeastern Washington State

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A vertical view of southeastern Washington States as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. The Snake River flows into the Columbia River in the most southerly corner of the picture. The Wallula Lake is below the junction of the two rivers. The Yakima Valley is at the southwestern edge of the photograph. The Columbia Basin is in the center of the picture. The Cascade Range extends across the northwest corner of the photograph.

  17. Predicting hydrological signatures in ungauged catchments using spatial interpolation, index model, and rainfall-runoff modelling

    NASA Astrophysics Data System (ADS)

    Zhang, Yongqiang; Vaze, Jai; Chiew, Francis H. S.; Teng, Jin; Li, Ming

    2014-09-01

    Understanding a catchment's behaviours in terms of its underlying hydrological signatures is a fundamental task in surface water hydrology. It can help in water resource management, catchment classification, and prediction of runoff time series. This study investigated three approaches for predicting six hydrological signatures in southeastern Australia. These approaches were (1) spatial interpolation with three weighting schemes, (2) index model that estimates hydrological signatures using catchment characteristics, and (3) classical rainfall-runoff modelling. The six hydrological signatures fell into two categories: (1) long-term aggregated signatures - annual runoff coefficient, mean of log-transformed daily runoff, and zero flow ratio, and (2) signatures obtained from daily flow metrics - concavity index, seasonality ratio of runoff, and standard deviation of log-transformed daily flow. A total of 228 unregulated catchments were selected, with half the catchments randomly selected as gauged (or donors) for model building and the rest considered as ungauged (or receivers) to evaluate performance of the three approaches. The results showed that for two long-term aggregated signatures - the log-transformed daily runoff and runoff coefficient, the index model and rainfall-runoff modelling performed similarly, and were better than the spatial interpolation methods. For the zero flow ratio, the index model was best and the rainfall-runoff modelling performed worst. The other three signatures, derived from daily flow metrics and considered to be salient flow characteristics, were best predicted by the spatial interpolation methods of inverse distance weighting (IDW) and kriging. Comparison of flow duration curves predicted by the three approaches showed that the IDW method was best. The results found here provide guidelines for choosing the most appropriate approach for predicting hydrological behaviours at large scales.

  18. Catchment classification by means of hydrological models

    NASA Astrophysics Data System (ADS)

    Hellebrand, Hugo; Ley, Rita; Casper, Markus

    2013-04-01

    An important hydrological objective is catchment classification that will serve as a basis for the regionalisation of discharge parameters or model parameters. The main task of this study is the development and assessment of two classification approaches with respect to their efficiency in catchment classification. The study area in western Germany comprises about 80 catchments that range in size from 8 km2 up to 1500 km2, covering a wide range of geological substrata, soils, landscapes and mean annual precipitation. In a first approach Self Organising Maps (SOMs) use discharge characteristics or catchment characteristics to classify the catchments of the study area. Next, a reference hydrological model calibrates the catchments of the study area and tests the possibilities of parameter transfer. Compared to the transfer of parameters outside a class, for most catchments the model performance improves when parameters within a class are transferred. Thus, it should be possible to distinguish catchment classes by means of a hydrological model. The classification results of the SOM are compared to the classification results of the reference hydrological model in order to determine the latter validity. The second approach builds on the first approach in such a way that it uses the Superflex Modelling Framework instead of only one reference model. Within this framework multiple conceptual model structures can be calibrated and adapted. Input data for each calibration of a catchment are hourly time series of runoff, precipitation and evaporation for at least eight years. The calibration of multiple models for each catchment and their comparison allows for the assessment of the influence of different model structures on model performance. Learning loops analyse model performance and adapt model structures accordingly with a view to performance improvement. The result of the modelling exercise is a best performing model structure for each catchment that serves as a basis

  19. Hydropedological insights when considering catchment classification

    NASA Astrophysics Data System (ADS)

    Bouma, J.; Droogers, P.; Sonneveld, M. P. W.; Ritsema, C. J.; Hunink, J. E.; Immerzeel, W. W.; Kauffman, S.

    2011-06-01

    Soil classification systems are analysed to explore the potential of developing classification systems for catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. This principle also applies to catchments. However, to be useful, soil classifications have to be based on permanent characteristics as formed by the soil forming factors over often very long periods of time. When defining permanent catchment characteristics, discharge data would therefore appear to be less suitable. But permanent soil characteristics do not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards the required functional characterization of soils as is illustrated for three recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous soils with varying soil structures during the year and about spatial and temporal variability. The suggestion is made therefore to first focus on improving simulation of catchment hydrology, possibly incorporating hydropedological expertise, before embarking on a catchment classification effort which involves major input of time and involves the risk of distraction. In doing so, we suggest to also define other characteristics for catchment performance than the traditionally measured discharge rates. Such characteristics may well be derived from societal issues being studied, as is illustrated for the Green Water Credits program.

  20. Process type identification in torrential catchments

    NASA Astrophysics Data System (ADS)

    Heiser, Micha; Scheidl, Christian; Eisl, Julia; Spangl, Bernhard; Hübl, Johannes

    2015-04-01

    The classification of torrential processes takes place according to factors like sediment concentration and flow behavior and ranges from fluvial process types, including water floods and fluvial sediment transport processes, to fluvial mass movements such as debris flows. This study hypothises a context between basic geomorphological disposition parameters and potential dominant flow process types in steep headwater catchments. Thus, examined catchments were selected based on a historical event documentation of torrential events in the Austrian Alps. In total, 84 catchments could be analysed, and 11 different morphometric parameters were considered. To predict the dominant torrential process type within a catchment, a naive Bayes classifier, a decision tree model, and a multinomial regression model was trained against the compiled geomorphological disposition parameters. All models as well as their combination were compared, based on bootstrapping and complexity. The presented classification model with the lowest prediction error for our data might help to identify the most likely torrential process within a considered catchment.

  1. Middle Miocene to present sediment transport and deposits in the Southeastern Weddell Sea, Antarctica

    NASA Astrophysics Data System (ADS)

    Huang, Xiaoxia; Jokat, Wilfried

    2016-04-01

    Understanding the transport and deposition of sediments along the Antarctic continental shelves helps to provide constraints on past ice sheet dynamics. Seismic stratigraphic and scientific drilling data from the Antarctic continental margins have provided much direct evidence concerning ice sheet evolution and sedimentation history. In this study, we describe a series of sedimentary features along the continental margin of the southeastern Weddell Sea to constrain glacial-influenced sedimentation processes from the Middle Miocene to the present. The Crary Trough Mouth Fan (CTMF), channel systems, Mix-system turbidity-contourites are investigated by using seismic reflection, sub-bottom profiler, and results from ODP Site 693. The sinuous, NE-SW-oriented turbidity-contourites are characterized by bathymetric highs that are more than 150 km wide, 700 km long, and have a sediment thickness of up to 2 km. The unique sedimentation environment of the southeastern Weddell Sea is controlled by a large catchment area and its fast (paleo-)ice streams feeding the Filchner Ronne Ice Shelf, turbidity/bottom currents as well as sea level changes. A remarkable increase in mass transport deposits (MTDs) in the Late Miocene and Early Pliocene strata has been related to, ice sheet loading, eustatic sea level fall, earthquakes, and overpressure of rapid sediment accumulation. Our seismic records also imply that fluctuations of East Antarctic ice sheet similar to those that occurred during the last glacial cycle might have been typical for southeastern Weddell Sea during glacial periods since the Late Miocene or even earlier.

  2. Arsenic occurrence in Brazil and human exposure.

    PubMed

    de Figueiredo, Bernardino Ribeiro; Borba, Ricardo Perobelli; Angélica, Rômulo Simões

    2007-04-01

    Environmental exposure to arsenic (As) in terms of public health is receiving increasing attention worldwide following cases of mass contamination in different parts of the world. However, there is a scarcity of data available on As geochemistry in Brazilian territory, despite the known occurrence of As in some of the more severely polluted areas of Brazil. The purpose of this paper is to discuss existing data on As distribution in Brazil based on recent investigations in three contaminated areas as well as results from the literature. To date, integrated studies on environmental and anthropogenic sources of As contamination have been carried out only in three areas in Brazil: (1) the Southeastern region, known as the Iron Quadrangle, where As was released into the drainage systems, soils and atmosphere as a result of gold mining; (2) the Ribeira Valley, where As occurs in Pb-Zn mine wastes and naturally in As-rich rocks and soils; (3) the Amazon region, including the Santana area, where As is associated with manganese ores mined over the last 50 years. Toxicological studies revealed that the populations were not exposed to elevated levels of As, with the As concentrations in surface water in these areas rarely exceeding 10 microg/L. Deep weathering of bedrocks along with formation of Fe/Al-enriched soils and sediments function as a chemical barrier that prevents the release of As into the water. In addition, the tropical climate results in high rates of precipitation in the northern and southeastern regions and, hence, the As contents of drinking water is diluted. Severe cases of human As exposure related to non-point pollution sources have not been reported in Brazil. However, increasing awareness of the adverse health effects of As will eventually lead to a more complete picture of the distribution of As in Brazil. PMID:17351814

  3. Hydrogeological impacts of a railway tunnel in fractured Precambrian gneiss rocks (south-eastern Norway)

    NASA Astrophysics Data System (ADS)

    Kværner, Jens; Snilsberg, Petter

    2013-11-01

    Groundwater monitoring along the Romeriksporten tunnel, south-eastern Norway, provided an opportunity for studying the impacts of tunnelling on groundwater in fractured Precambrian gneiss rocks, and examining relations between bedrock hydrology, tectonic weakness zones and catchments. Tunnel leakage resulted in groundwater drawdown up to 35 m in weakness zones, converted groundwater discharge zones into recharge zones, and affected groundwater chemistry. The magnitude of drawdown and fluctuations in groundwater level differed between weakness zones, and varied with distance from the tunnel route, tunnel leakage, and recharge from catchments. Clear differences in groundwater level and fluctuation patterns indicated restricted groundwater flow between weakness zones. The groundwater drawdowns demonstrated coherent water-bearing networks to 180-m depth in faults and fracture zones. Similar groundwater levels with highly correlated fluctuations demonstrated hydraulic connectivity within fracture zones. Different groundwater drawdown and leakage in weakness zones with different appearance and influence of tectonic events demonstrated the importance of the geological history for bedrock hydrogeology. Water injection into the bedrock counteracted groundwater drawdowns. Even moderate leakage to underground constructions may lead to large groundwater drawdown in areas with small groundwater recharge. Hydrogeological interpretation of tectonic weakness zones should occur in the context of geological history and local catchment hydrology.

  4. Collaborative knowledge in catchment research networks

    NASA Astrophysics Data System (ADS)

    Macleod, Christopher Kit

    2015-04-01

    There is a need to improve the production, sharing and use of collaborative knowledge of catchment systems through networks of researchers, policy makers and practitioners. This requires greater levels of systems based integrative research. In parallel to the growing realization that greater levels of collaborative knowledge in scientific research networks are required, a digital revolution has been taking place. This has been driven primarily by the emergence of distributed networks of computers and standards-based interoperability. The objective of this paper is to present the status and research needs for greater levels of systems based integrative research for the production, sharing and use of collaborative knowledge in catchment research networks. To enable increased levels of integrative research depends on development and application of digital technologies to improve collection, use and sharing of data and devise new knowledge infrastructures. This paper focuses on the requirements for catchment observatories that integrate existing and novel physical, social and digital networks of knowledge infrastructures. To support this focus, I present three leading international examples of collaborative networks of catchment researchers and their development of catchment observatories. In particular, the digital infrastructures they have developed to support collaborative knowledge in catchment research networks. These examples are from North America (NSF funded CUAHSI HIS) and from Europe (UK NERC funded EVOp and the German Helmholtz Association Centers funded TERENO/TEODOOR). These exemplars all supported advancing collaborative knowledge in catchment research networks through the development of catchment observatories. I will conclude by discussing the future research directions required for greater levels of production, sharing and use of collaborative knowledge in catchment research networks based on catchment systems science.

  5. Distribution of two species of Nephropsis Wood-Mason, 1872 (Crustacea, Decapoda, Nephropidae) from northeastern Brazil.

    PubMed

    Alves-Júnior, Flavio De Almeida; Araújo, Marina De Sá Leitão Câmara De; Souza-Filho, Jesser F

    2016-01-01

    The genus Nephropsis Wood-Mason, 1872 has been reported from Brazil by Tavares (1998), Tavares & Young (2002), Silva et al. (2003), Dall´Occo et al. (2007) and Serejo et al. (2007), recording Nephropsis aculeata Smith, 1881, N. rosea Bate, 1888 and N. agassizii A. Milne-Edwards, 1880, the last of which occurs in both northeastern and southeastern of Brazil. PMID:27395116

  6. Doing hydrology backwards in tropical humid catchments

    NASA Astrophysics Data System (ADS)

    Real Rangel, R.; Brena-Naranjo, J. A.; Pedrozo-Acuña, A.

    2015-12-01

    Top-down approaches in hydrology offer the possibility to predict water fluxes at the catchment scale based on the interpretation of the observed hydrological response at the catchment itself. Doing hydrology backwards (inferring precipitation and evapotranspiration rates at the catchment scale from streamflow measurements, see Kirchner (2009)) can be a useful methodology for estimating water fluxes at the catchment and regional scales. Previous studies using this inverse modeling approach have been performed in regions (UK, Switzerland, France, Eastern US) where energy-limited (in winter and early spring) and water-limited conditions (in summer) prevail during a large period of the year. However, such approach has not been tested in regions characterized by a quasi-constant supply of water and energy (e.g. humid tropics). The objective of this work is to infer annual rates of precipitation and evapotranspiration over the last decade in 10 catchments located in Mexico's tropical humid regions. Hourly discharge measurements during recession periods were analyzed and parameters for the nonlinear storage-discharge relationship of each catchment were derived. Results showed large variability in both catchment-scale precipitation and evapotranspiration rates among the selected study sites. Finally, a comparison was done between such estimates and those obtained from remotely-sensed data (TRMM for precipitation and MOD16 for evapotranspiration).

  7. Catchment water storage: Models vs Measurements

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary

    2016-04-01

    Recent years have seen a great deal of progress in development of hydrological models that can simulate both the dynamic streamflow response and the hydrochemical flux response of a catchment. In general terms, streamflow response is driven by water deficit in the catchment, whereas hydrochemical response is driven by water storage. Therefore, models that can simultaneously predict both responses must succeed in representing these two related, but different, quantities. This presentation will consider how much information we can gain from field studies to quantify the joint deficit/storage state of a catchment. In particular, examples from two New Zealand experimental catchments in lowland and high country locations will be used to link typical measurements available with the information required by hydrological - hydrochemical models. I will then use the example catchments to assess how well the structure of a typical hydrological-hydrochemical model is supported by field measurements. In particular, can we quantify catchment storage and link this to flow response? Can we incorporate our knowledge of plant water use into such a model, including timing and depth of water withdrawn by the plant? What can field measurements tell us about spatial variability in hydrological-hydrochemical response and can this be represented in the model? I will conclude by discussing what we can learn from field data about the major challenges ahead in catchment storage modelling.

  8. Water Catchment and Storage Monitoring

    NASA Astrophysics Data System (ADS)

    Bruenig, Michael; Dunbabin, Matt; Moore, Darren

    2010-05-01

    Sensors and Sensor Networks technologies provide the means for comprehensive understanding of natural processes in the environment by radically increasing the availability of empirical data about the natural world. This step change is achieved through a dramatic reduction in the cost of data acquisition and many orders of magnitude increase in the spatial and temporal granularity of measurements. Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) is undertaking a strategic research program developing wireless sensor network technology for environmental monitoring. As part of this research initiative, we are engaging with government agencies to densely monitor water catchments and storages, thereby enhancing understanding of the environmental processes that affect water quality. In the Gold Coast hinterland in Queensland, Australia, we are building sensor networks to monitor restoration of rainforest within the catchment, and to monitor methane flux release and water quality in the water storages. This poster will present our ongoing work in this region of eastern Australia. The Springbrook plateau in the Gold Coast hinterland lies within a World Heritage listed area, has uniquely high rainfall, hosts a wide range of environmental gradients, and forms part of the catchment for Gold Coast's water storages. Parts of the plateau are being restored from agricultural grassland to native rainforest vegetation. Since April 2008, we have had a 10-node, multi-hop sensor network deployed there to monitor microclimate variables. This network will be expanded to 50-nodes in February 2010, and to around 200-nodes and 1000 sensors by mid-2011, spread over an area of approximately 0.8 square kilometers. The extremely dense microclimate sensing will enhance knowledge of the environmental factors that enhance or inhibit the regeneration of native rainforest. The final network will also include nodes with acoustic and image sensing capability for

  9. Pseudo Paired Catchments Analysis to Assess the Impact of Urbanization on Catchment Hydrology

    NASA Astrophysics Data System (ADS)

    Salavati, B.; Oudin, L.; Furusho, C.; Ribstein, P.

    2014-12-01

    Paired catchments analysis provides a robust approach to assess the impact of land use changes on catchment's hydrological response. This approach is limited by the availability of data for two neighbor catchments with and without land use changes under similar climate conditions. Thus, hydrological modelling approaches are also very popular since they do not depend on data of a reference catchment. In the present study, 70 urbanized and non-urbanized paired catchments were selected in the United States. Unit housing density maps over the 1940-2010 time period were used to reconstruct historic impervious area extents with aproximatly the same resolution as the National Land Cover Database (NLCD) maps. Two approaches were compared to assess the impact of urbanization on catchment-scale hydrology: the classical paired catchments approach using observed flow time series and an alternative paired catchments approach involving hydrological modeling that allows to simulate a virtual control catchment. To this aim, the GR4J model, a conceptual daily 4-parameter hydrological model, was used. The parameters of the model calibrated on the pre urbanization period were used to predict the streamflow that would have occurred in the urban catchment if the urbanization had not taken place. Then, classical statistical methods involving ANCOVA were used to detect the significance and to quantify the change on the hydrological responses due to land use changes. Results show that the two approaches lead to similar conclusions on the impact of urbanization on catchment hydrology. Thus, the modelling approach provides a relevant alternative for case studies where data of reference catchments are not available.

  10. Pertussis Outbreak, Southeastern Minnesota, 2012

    PubMed Central

    Theofiles, Alexander G.; Cunningham, Scott A.; Chia, Nicholas; Jeraldo, Patricio R.; Quest, Daniel J.; Mandrekar, Jayawant N.; Patel, Robin

    2015-01-01

    Objective To describe clinical and laboratory findings from the 2012 southeastern Minnesota pertussis outbreak. Patients and Methods Patients were selected for 2 parts of the study. In the first part, nasopharyngeal swabs from a convenience sample of 265 unique patients were used for both the clinician-requested polymerase chain reaction (PCR) test and culture. B pertussis isolates were tested for macrolide susceptibility and typed using whole genome sequencing and pulsed-field gel electrophoresis. Pertactin gene sequences were analyzed to identify pertactin-deficient B pertussis. In the second part, all patients seen at Mayo Clinic in Rochester, Minnesota, who had PCR results positive for Bordetella pertussis or Bordetella parapertussis between January 1, 2012, and December 31, 2012, were analyzed for patient demographic features and vaccination records. Results One hundred sixty patients had results positive for B pertussis, and 21 patients had results positive for B parapertussis. Among the 265 swabs cultured, B pertussis was detected by both culture and PCR in 11. One swab was positive for B pertussis by culture alone, and 13 were positive by PCR alone. Polymerase chain reaction detected B pertussis more frequently than did culture (P=.001). No macrolide resistance was detected. All 12 isolates tested had an altered pertactin gene, including 9 with a signal sequence deletion, 2 with insertion sequence disruptions, and 1 with a premature stop codon. Nine and 3 isolates were pertactin types prn1 and prn2, respectively. Whole genome sequencing and pulsed-field gel electrophoresis detected the presence of multiple B pertussis strains. The mean age of patients with pertussis was younger than that of those without pertussis (15.6 and 25.5 years, respectively; P=.002). Compared with those whose test results were negative for B pertussis, fewer patients with positive results had received whole-cell pertussis vaccine (P=.02). In the subgroup who had received acellular

  11. Evapotranspiration following wildfire in resprouting eucalypt forests: from leaf to catchment

    NASA Astrophysics Data System (ADS)

    Nolan, Rachael; Lane, Patrick; Benyon, Richard; Bradstock, Ross; Mitchell, Patrick

    2014-05-01

    Forests which recover from disturbance predominately via vegetative resprouting may be expected to have different catchment water balance dynamics following wildfire than forests recovering from seed. However, the impacts of wildfire on evapotranspiration (Et) are largely unknown in resprouting forest types. This is despite their dominance across the majority of southern Australia's forested catchments and the large areas burnt in recent years. Following wildfires in south-eastern Australia in 2006 and 2009, we monitored Et over two years using a combination of sapflow, rainfall interception and forest floor Et methods. We also measured changes in forest structure and leaf physiology. We found that fire initially reduced Et, but this recovered rapidly and even increased above rates observed in unburnt forest. Post-fire changes in Et were dependent on fire severity with higher rates only observed in forest burnt at moderate severity (<70% canopy scorch). Measurements of leaf physiology indicated higher rates of stomatal conductance in seedlings, and to a lesser extent in resprouting epicormic leaves, which may be driving higher rates of water use per unit leaf area in regenerating forest compared to unburnt forest. We also found higher leaf area index in burnt forest over 2-3 years post-fire. These results demonstrate that resprouting forest types have a relatively rapid recovery of Et due to both leaf-scale physiological processes and recovery of stand-scale leaf area. These plot-scale observations of Et were compared with changes in streamflow measured from a catchment burnt mostly at moderate severity in 2006. Time-trend analysis on pre- and post-fire streamflow found that mean annual water yield reduced by an average 197 mm over 1-4 years post-fire. This was attributed to both drought, which was estimated to account for 54% of reductions, and increased Et across the catchment following fire, which is consistent with plot-scale observations.

  12. Comparing flow duration curve and rainfall-runoff modelling for predicting daily runoff in ungauged catchments

    NASA Astrophysics Data System (ADS)

    Zhang, Yongqiang; Vaze, Jai; Chiew, Francis H. S.; Li, Ming

    2015-06-01

    Predicting daily runoff time series in ungauged catchments is both important and challenging. For the last few decades, the rainfall-runoff (RR) modelling approach has been the method of choice. There have been very few studies reported in literature which attempt to use flow duration curve (FDC) to predict daily runoff time series. This study comprehensively compares the two approaches using an extensive dataset (228 catchments) for a large region of south-eastern Australia and provides guidelines for choosing the suitable method. For each approach we used the nearest neighbour method and two weightings - a 5-donor simple mathematical average (SA) and a 5-donor inverse-distance weighting (5-IDW) - to predict daily runoff time series. The results show that 5-IDW was noticeably better than a single donor to predict daily runoff time series, especially for the FDC approach. The RR modelling approach calibrated against daily runoff outperformed the FDC approach for predicting high flows. The FDC approach was better at predicting medium to low flows in traditional calibration against the Nash-Sutcliffe-Efficiency or Root Mean Square Error, but when calibrated against a low flow objective function, both the FDC and rainfall-runoff models performed equally well in simulating the low flows. These results indicate that both methods can be further improved to simulate daily hydrographs describing the range of flow metrics in ungauged catchments. Further studies should be carried out for improving the accuracy of predicted FDC in ungauged catchments, including improving the FDC model structure and parameter fitting.

  13. City of Belo Horizante, State of Minas Gerais, Brazil, South America

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The city of Belo Horizante, State of Minas Gerais, (20.0S, 44.0W) is a relatively new community in southeastern Brazil. It lies about 225 miles north of Rio de Janeiro and occupies an area of rolling and hilly terrain. The economy is based on a mixture of agriculture, cattle grazing, mining and manufacturing.

  14. Spectral Analysis in Catchment Hydrology and Geochemistry

    NASA Astrophysics Data System (ADS)

    Kirchner, J. W.; Feng, X.; Renshaw, C. E.; Neal, C.

    2001-12-01

    Spectral analysis of chemical tracer time series can be used to probe the internal workings of catchments. It has recently been shown that catchments act as fractal filters for inert chemical tracers like chloride, converting "white noise" rainfall chemistry inputs into fractal "1/f noise" runoff chemistry time series (Kirchner et al., 2000). This implies that catchments have long-tailed travel time distributions, and thus retain soluble contaminants for unexpectedly long timespans. Long-term monitoring data from North America, Britain, and Scandinavia show that this fractal behavior characterizes a wide array of catchments. How can this fractal scaling arise in such diverse settings? One can show that advection and dispersion of spatially distributed rainfall tracer inputs will generate fractal tracer time series, as long as the flow system is highly dispersive (Kirchner et al., in press). This implies that subsurface flow in small catchments is dominated by large conductivity contrasts, such as arise from macropores, fracture networks, and similar large-scale heterogeneities in subsurface conductivity. One can also use spectral methods to analyze long-term time series of water fluxes in rainfall and streamflow. Spectral analysis of hydrologic time series measures the downslope propagation of the hydraulic potential waves that mobilize runoff, whereas spectral analysis of tracer time series clocks the propagation of water itself through the catchment. Water fluxes in streamflow exhibit non-fractal scaling, instead of the fractal 1/f scaling shown by chemical tracers. These observations imply that hydrologic signals are transmitted downslope more rapidly, and with much less dispersion, than chemical tracer signals are. Thus small upland catchments transmit hydraulic potentials (which drive runoff) much less dispersively than they transport water itself. These observations provide important constraints for theoretical models of subsurface flow and transport in

  15. Southeastern Alaska tectonostratigraphic terranes revisited

    SciTech Connect

    Brew, D.A.; Ford, A.B.

    1985-04-01

    The presence of only three major tectonostratigraphic terranes (TSTs) in southeastern Alaska and northwestern British Columbia (Chugach, Wrangell, and Alexander) is indicated by critical analysis of available age, stratigraphic, and structural data. A possible fourth TST (Stikine) is probably an equivalent of part or all of the Alexander. The Yakutat block belongs to the Chugach TST, and both are closely linked to the Wrangell and Alexander(-Stikine) TSTs; the Gravina TST is an overlap assemblage. THe Alexander(-Stikine) TSTs is subdivided on the basis of age and facies. The subterranes within it share common substrates and represent large-scale facies changes in a long-lived island-arc environment. The Taku TSTs is the metamorphic equivalent of the upper part (Permian and Upper Triassic) of the Alexander(-Stikine) TSTs with some fossil evidence preserved that indicates the age of protoliths. Similarly, the Tracy Arm TST is the metamorphic equivalent of (1) the lower (Ordovician to Carboniferous) Alexander TST without any such fossil evidence and (2) the upper (Permian to Triassic) Alexander(-Stikine) with some newly discovered fossil evidence. Evidence for the ages of juxtaposition of the TSTs is limited. The Chugach TST deformed against the Wrangell and Alexander TSTs in late Cretaceous. Gravina rocks were deformed at the time and also earlier. The Wrangell TST was stitched to the Alexander(-Stikine) by middle Cretaceous plutons but may have arrived before its Late Jurassic plutons were emplaced. The Alexander(-Stikine) and Cache Creek TSTs were juxtaposed before Late Triassic.

  16. A differential equation for specific catchment area

    NASA Astrophysics Data System (ADS)

    Gallant, John C.; Hutchinson, Michael F.

    2011-05-01

    Analysis of the behavior of specific catchment area in a stream tube leads to a simple nonlinear differential equation describing the rate of change of specific catchment area along a flow path. The differential equation can be integrated numerically along a flow path to calculate specific catchment area at any point on a digital elevation model without requiring the usual estimates of catchment area and width. The method is more computationally intensive than most grid-based methods for calculating specific catchment area, so its main application is as a reference against which conventional methods can be tested. This is the first method that provides a benchmark for more approximate methods in complex terrain with both convergent and divergent areas, not just on simple surfaces for which analytical solutions are known. Preliminary evaluation of the D8, M8, digital elevation model networks (DEMON), and D∞ methods indicate that the D∞ method is the best of those methods for estimating specific catchment area, but all methods overestimate in divergent terrain.

  17. Topic: Catchment system dynamics: Processes and feedbacks

    NASA Astrophysics Data System (ADS)

    Keesstra, Saskia

    2015-04-01

    In this meeting we can talk about my main expertise: the focus of my research ocus revolves around understanding catchment system dynamics in a holistic way by incorporating both processes on hillslopes as well as in the river channel. Process knowledge enables explanation of the impact of natural and human drivers on the catchment systems and which consequences these drivers have for water and sediment connectivity. Improved understanding of the catchment sediment and water dynamics will empower sustainable land and river management and mitigate soil threats like erosion and off-side water and sediment accumulation with the help of nature's forces. To be able to understand the system dynamics of a catchment, you need to study the catchment system in a holistic way. In many studies only the hillslopes or even plots are studied; or only the channel. However, these systems are connected and should be evaluated together. When studying a catchment system any intervention to the system will create both on- as well as off sites effects, which should especially be taken into account when transferring science into policy regulations or management decisions.

  18. Central Brazil

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This Moderate resolution Imaging Spectroradiometer (MODIS) true-color image was acquired on October 19, 2000, over a region in Brazil large enough to show much of the country's diverse landscape. Spanning some 8.5 million square kilometers (3.2 million square miles), Brazil is by far the largest South American nation--both in terms of land and population. The region known as the Amazon Basin lies to the northwest (upper left) and extends well beyond the northern and western edges of this scene. Typically, from this perspective Amazonia appears as a lush, dark green carpet due to the thick canopy of vegetation growing there. Some of the Amazon Basin is visible in this image, but much is obscured by clouds (bright white pixels), as is the Amazon River. This region is home to countless plant and animal species and some 150,000 native South Americans. The clusters of square and rectangular patterns toward the center of the image (light green or reddish-brown pixels) are where people have cleared away trees and vegetation to make room for development and agriculture. Toward the western side of the scene there is considerable haze and smoke from widespread biomass burning in parts of Brazil and Bolivia, which shares its eastern border with Brazil. Toward the east in this image is the highland, or 'cerrado,' region, which is more sparsely vegetated and has a somewhat drier climate than the Amazon Basin. The capital city, Brasilia, lies within this region just southwest of the Geral de Goias Mountains (orangish pixels running north-south). There are two large water reservoirs visible in this scene--the Sobradinho Reservoir about 800 km (500 miles) northeast of Brasilia, and the Paranaiba about 500 km (300 miles) southwest of Brasilia. MODIS flies aboard NASA's Terra spacecraft. Image courtesy Brian Montgomery, Reto Stockli, and Robert Simmon, based on data from the MODIS Science Team.

  19. Non-Linearity of the Rainfall-Runoff Response Across South-Eastern Australia During the Millennium Drought

    NASA Astrophysics Data System (ADS)

    Post, D. A.; Potter, N. J.; Petheram, C.; Dawes, W.

    2012-12-01

    South-eastern Australia experienced a major drought lasting from 1997 to 2009 (the so-called 'Millennium drought'). Average annual rainfall during this drought was 512 mm, some 12 percent below the long-term average of 582 mm. Based on simple rules-of-thumb, one would expect a rainfall decline of this magnitude to produce a runoff decline of 20 to 30 percent. However, the decline in runoff during the Millennium drought was, in some places, much greater than this. There were a number of factors contributing to this. Firstly was the nature of the rainfall decline, which saw large decreases in autumn and winter rainfall, the seasons which produce most of the runoff across the region. There was also a lack of wet years and, more importantly, very wet months, with 180 consecutive months without a monthly rainfall in the top 10th percentile. Finally, temperatures during this drought were higher than during similar droughts in the past. These conditions led to a reduction in groundwater recharge, which resulted in groundwater levels falling many metres below the surface in some catchments. This led to streams which were previously 'gaining streams' becoming 'losing streams'. In this presentation, we will present rainfall, runoff and groundwater data from a number of catchments in south-eastern Australia, showing that following a large drop in groundwater levels, runoff coefficients decreased dramatically, while cease-to-flow days showed a similarly large increase. We will also present results from a modelling experiment showing that these changes in hydrologic functioning are more likely to occur in low relief catchments, and that farm dams may act to prolong the declines in runoff due to their ability to act as a store for surface water, thereby delaying the catchment response to rainfall. Finally, we discuss how lumped conceptual rainfall-runoff models may be modified in order to capture these observed shifts in the hydrologic functioning of catchments.nnual time series

  20. Towards catchment classification by means of environmental tracers and landscape analysis: The Attert catchment in Luxembourg

    NASA Astrophysics Data System (ADS)

    Wrede, S.; Pfister, L.; Krein, A.; Fenicia, F.; Bogaard, T. A.; Uhlenbrook, S.; Savenije, H. H. G.

    2010-05-01

    Until recently hydrological research has been mainly focusing on detailed investigations at small spatial scales, resulting in a set of more and more complex physically-based and spatially distributed hydrologic models. While much of the research effort today is targeted to advance these hydrological model predictions at the catchment scale, shortcomings remain to adequately capture the dominating hydrological processes across a range of scales that translate into the rainfall-runoff response of a catchment. Thus, studies addressing the fundamental relations between catchment structure and function are urgently needed, as they help catchment classification by advancing our knowledge about suitable catchment signatures and controls at different spatial and temporal scales. In our study in the nested Attert catchment in the Grand-Duchy of Luxembourg (Europe) we investigate how environmental tracer dynamics, hydrological response behavior and landscape analysis can help to identify such dominating controls on runoff generation across multiple scales. Techniques to characterize landscape structure and hydrological processes are complementary applied to identify scales in which shifts of the dominant hydrological processes occur. These dominating controls in turn provide a more integrated perspective of catchment structure and functioning that can be used for catchment classification based on functional response.

  1. Drought characteristics and related risks in large and mesoscale tropical catchments in Latin-America and South East Asia

    NASA Astrophysics Data System (ADS)

    Nauditt, Alexandra; Ribbe, Lars; Birkel, Christian; Célleri, Rolando

    2016-04-01

    Seasonal meteorological and hydrological droughts are a recurrent phenomenon in water abundant tropical countries and are expected to become more frequent in the future. Unusual water shortage in the past months and years has severely affected societies living in the Paraiba do Sul river basin (Brazil), the Mekong, as well as in a number of basins in Central America and Vietnam among many others. Preparedness, however, is absent and site appropriate water management measures and strategies are not available. While drought related research and water management in recent years has been widely addressed in water scarce subtropical regions, the US and Europe, not much attention has been paid to drought risk in tropical catchments. Available daily or monthly precipitation and runoff time series for catchments in Brazil, Costa Rica, Ecuador, the Mekong region and Vietnam were analysed to compare historical meteorological and hydrological drought frequency (SPI/SRI). The role of tropical catchment characteristics, storage and climate variability in seasonal drought evolvement was investigated by applying the conceptual semi-distributed HBV light model to two undisturbed catchments in Central Vietnam and 18 catchments of a size of 70-5000 km² in Costa Rica. For the Mekong and the Paraíba de Sul, the hydrological module of the WEAP model was applied to undisturbed subcatchments with the same objective. To understand and separate the anthropogenic impact on drought evolvement, the abstractions (irrigation, reservoirs, water supply) and hydrological alterations were observed and quantified by applying water allocation and balance model WEAP. We conclude that such a combined model-data analysis that equally accounts for landscape related and anthropogenic impacts on the local hydrological cycle is a useful approach for drought management in tropical countries.

  2. Leaf blade anatomy and ultrastructure of six Simira species (Rubiaceae) from the Atlantic rain forest, Brazil.

    PubMed

    Moraes, Tarsila Maria da Silva; Barros, Claudia Franca; Silva Neto, Sebastião José; Gomes, Valdirene Moreira; Da Cunha, Maura

    2009-12-01

    Simira is a predominantly woody Neotropical genus comprising 41 taxa, 16 of which occur in Brazil and eight of them in the southeastern region of Brazil. Leaf blades of Simira eliezeriana Peixoto, S. glaziovii (K. Schum.) Steyem., S. grazielae Peixoto, S. pikia (K. Schum.) Steyerm., S. rubra (Mart.) Steyerm., S. sampaioana (Standl.) Steyerm. were collected in the southeastern region of Brazil and fixed according to usual methods for light and electron microscopy. The leaf blades show typical characteristics of the Rubiaceae family as dorsiventral mesophyll and paracytic stomata. The presence of two bundle sheaths that extend to the upper epidermal layer, prismatic crystal and crystal-sand, alkaloids in the mesophyll and the organization micromorphological of the outer periclinal wall are considered characteristics representative for the genus. This study also demonstrates some leaf blade characteristics that can be used to Simira species identification (leaf surface, domatia types, epicuticular wax types and patterns of epidermis anticlinal cell walls). PMID:20067031

  3. A Regional Modeling Framework of Phosphorus Sources and Transport in Streams of the Southeastern United States1

    PubMed Central

    García, Ana María; Hoos, Anne B; Terziotti, Silvia

    2011-01-01

    Abstract We applied the SPARROW model to estimate phosphorus transport from catchments to stream reaches and subsequent delivery to major receiving water bodies in the Southeastern United States (U.S.). We show that six source variables and five land-to-water transport variables are significant (p<0.05) in explaining 67% of the variability in long-term log-transformed mean annual phosphorus yields. Three land-to-water variables are a subset of landscape characteristics that have been used as transport factors in phosphorus indices developed by state agencies and are identified through experimental research as influencing land-to-water phosphorus transport at field and plot scales. Two land-to-water variables – soil organic matter and soil pH – are associated with phosphorus sorption, a significant finding given that most state-developed phosphorus indices do not explicitly contain variables for sorption processes. Our findings for Southeastern U.S. streams emphasize the importance of accounting for phosphorus present in the soil profile to predict attainable instream water quality. Regional estimates of phosphorus associated with soil-parent rock were highly significant in explaining instream phosphorus yield variability. Model predictions associate 31% of phosphorus delivered to receiving water bodies to geology and the highest total phosphorus yields in the Southeast were catchments with already high background levels that have been impacted by human activity. PMID:22457579

  4. Energetics of southeastern Pacific cut-off lows

    NASA Astrophysics Data System (ADS)

    Gan, Manoel Alonso; Piva, Everson Dal

    2015-08-01

    The existence of cut-off lows (COLs) over South Pacific and South America is often associated with adverse weather events such as intense precipitation over the central region of South America, frost episodes in southern Brazil and the development of Andes lee cyclones and intense cyclones over the southern coast of Brazil. Despite this importance, the formation and maintenance mechanisms of the COLs are not well understood. To detail the significant variability in terms of the eddy kinetic energy equation for fifty cases of COLs that formed over the southeastern Pacific Ocean is the aim of this study. Only the cases of COLs that formed over the ocean and remained there during most of their life were chosen. The main terms of the equation [ageostrophic flux convergence (AFC), baroclinic conversion (BRC) and barotropic conversion (BRT)] were calculated using the 6-hourly gridded data from the National Centers for Environmental Prediction/Department of Energy reanalysis. The formation mechanism of the COLs was associated with BRC and AFC. During the midlife period, the BRC term converted eddy kinetic energy to eddy potential energy and the AFC had a positive contribution until 6 h after the midlife point. In the dissipation phase, the BRC term remained positive and AFC became negative. The BRT extracted kinetic energy from the COL during the entire life cycle. The AFC term was the most important in all phases of the cut-off lifetime, and it was the responsible for extending the cut-off lifetime while the others terms were negatives.

  5. Energetics of southeastern Pacific cut-off lows

    NASA Astrophysics Data System (ADS)

    Gan, Manoel Alonso; Piva, Everson Dal

    2016-06-01

    The existence of cut-off lows (COLs) over South Pacific and South America is often associated with adverse weather events such as intense precipitation over the central region of South America, frost episodes in southern Brazil and the development of Andes lee cyclones and intense cyclones over the southern coast of Brazil. Despite this importance, the formation and maintenance mechanisms of the COLs are not well understood. To detail the significant variability in terms of the eddy kinetic energy equation for fifty cases of COLs that formed over the southeastern Pacific Ocean is the aim of this study. Only the cases of COLs that formed over the ocean and remained there during most of their life were chosen. The main terms of the equation [ageostrophic flux convergence (AFC), baroclinic conversion (BRC) and barotropic conversion (BRT)] were calculated using the 6-hourly gridded data from the National Centers for Environmental Prediction/Department of Energy reanalysis. The formation mechanism of the COLs was associated with BRC and AFC. During the midlife period, the BRC term converted eddy kinetic energy to eddy potential energy and the AFC had a positive contribution until 6 h after the midlife point. In the dissipation phase, the BRC term remained positive and AFC became negative. The BRT extracted kinetic energy from the COL during the entire life cycle. The AFC term was the most important in all phases of the cut-off lifetime, and it was the responsible for extending the cut-off lifetime while the others terms were negatives.

  6. Impact of climate change and water use policies on hydropower potential in the south-eastern Alpine region.

    PubMed

    Majone, Bruno; Villa, Francesca; Deidda, Roberto; Bellin, Alberto

    2016-02-01

    Climate change is expected to cause alterations of streamflow regimes in the Alpine region, with possible relevant consequences for several socio-economic sectors including hydropower production. The impact of climate change on water resources and hydropower production is evaluated with reference to the Noce catchment, which is located in the Southeastern Alps, Italy. Projected changes of precipitation and temperature, derived from an ensemble of 4 climate model (CM) runs for the period 2040-2070 under the SRES A1B emission scenario, have been downscaled and bias corrected before using them as climatic forcing in a hydrological model. Projections indicate an increase of the mean temperature of the catchment in the range 2-4K, depending on the climate model used. Projections of precipitation indicate an increase of annual precipitation in the range between 2% and 6% with larger changes in winter and autumn. Hydrological simulations show an increase of water yield during the period 2040-2070 with respect to 1970-2000. Furthermore, a transition from glacio-nival to nival regime is projected for the catchment. Hydrological regime is expected to change as a consequence of less winter precipitation falling as snow and anticipated melting in spring, with the runoff peak decreasing in intensity and anticipating from July to June. Changes in water availability reflect in the Technical Hydropower Potential (THP) of the catchment, with larger changes projected for the hydropower plants located at the highest altitudes. Finally, the impacts on THP of water use policies such as the introduction of prescriptions for minimum ecological flow (MEF) have been analyzed. Simulations indicate that in the lower part of the catchment reduction of the hydropower production due to MEF releases from the storage reservoirs counterbalances the benefits associated to the projected increases of inflows as foreseen by simulations driven only by climate change. PMID:25980972

  7. 75 FR 62530 - Southeastern Power Administration; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southeastern Power Administration; Notice of Filing October 1, 2010. Take.... and Replacement-2-A for the sale of power from Southeastern Power Administration's...

  8. What makes catchment management groups "tick"?

    PubMed

    Oliver, P

    2001-01-01

    The work of catchment management groups throughout Australia represents a significant economic and social investment in natural resource management. Institutional structures and policies, the role of on-ground coordinators, facilitation processes, citizen participation and social capital are critical factors influencing the success of catchment management groups. From a participant-researcher viewpoint, this paper signposts research directions and themes that are being pursued from the participant/coordinator, catchment group, and lead government/non-government agency perspective on the influence of these factors on the success of a catchment management group in the Pumicestone Region of Southeast Queensland, Australia. Research directions, themes and discussion/reflection points for practitioners include--the importance of understanding milieu; motivation; success; having fun; "networking networks"; involvement of "nontraditional" stakeholders; development of stakeholder/participant partnerships; learning from other practitioners; methods of stakeholder/participant representation; evaluation; the need for guiding principles or philosophy; the equivalence of planning, implementation, evaluation, and resourcing; catchments as fundamental units of Nature; continuity of support for groups; recognising a new role for government; working with existing networks; and the need for an eclectic approach to natural resource management. PMID:11424936

  9. Hydropedological insights when considering catchment classification

    NASA Astrophysics Data System (ADS)

    Bouma, J.; Droogers, P.; Sonneveld, M. P. W.; Ritsema, C. J.; Hunink, J. E.; Immerzeel, W. W.; Kauffman, S.

    2011-02-01

    Soil classification systems are analysed in relation to the functioning and characterisation of catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. However, such classifications are based on permanent characteristics as formed by the soil forming factors over often very long periods of time and this does not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards functional characterization of soils as is illustrated for recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous field soils with varying soil structures during the year and the suggestion is made to first focus on improving simulation of catchment hydrology, incorporating hydropedological expertise, before embarking on a classification effort which involves major input of time and involves the risk of distraction. In doing so, we advise to also define other characteristics for catchment performance than the traditionally measured discharge rates.

  10. Southeastern Power Administration 2012 Annual Report

    SciTech Connect

    2012-01-01

    Dear Secretary Moniz: I am pleased to submit Southeastern Power Administration’s (Southeastern) fiscal year (FY) 2012 Annual Report for your review. This report reflects our agency’s programs, accomplishments, operational, and financial activities for the 12-month period beginning October 1, 2011, and ending September 30, 2012. This past year, Southeastern marketed approximately 5.4 billion kilowatt-hours of energy to 487 wholesale customers in 10 southeastern states. Revenues from the sale of this power totaled about $263 million. With the financial assistance and support of Southeastern’s customers, funding for capitalized equipment purchases and replacements at hydroelectric facilities operated by the U.S. Army Corps of Engineers (Corps) continued in FY 2012. Currently, there are more than 214 customers participating in funding infrastructure renewal efforts of powerplants feeding the Georgia-Alabama-South Carolina, Kerr-Philpott, and Cumberland Systems. This funding, which totaled more than $71 million, provided much needed repairs and maintenance for aging projects in Southeastern’s marketing area. Drought conditions continued in the southeastern region of the United States this past year, particularly in the Savannah River Basin. Lack of rainfall strained our natural and financial resources. Power purchases for FY 2012 in the Georgia-Alabama-South Carolina System totaled approximately $29 million. About $8 million of this amount was for replacement power, which is purchased only during adverse water conditions in order to meet Southeastern’s customer contract requirements. Southeastern’s goal is to maximize the benefits of our region’s water resources. Competing uses of these resources will present another challenging year for Southeastern’s employees. With the cooperation and communication among the Department of Energy (DOE), preference customers, and Corps, I am certain Southeastern is positioned to meet these challenges in the future. We

  11. Southeastern Power Administration 2011 Annual Report

    SciTech Connect

    2011-12-31

    Dear Secretary Chu: I am pleased to submit Southeastern Power Administration’s (Southeastern) fiscal year (FY) 2011 Annual Report for your review. This report reflects our agency’s programs, accomplishments, operational, and financial activities for the 12-month period beginning October 1, 2010, and ending September 31, 2011. This past year, Southeastern marketed approximately 6.2 billion kilowatt-hours of energy to 489 wholesale customers in 10 southeastern states. Revenues from the sale of this power totaled more than $264 million. With the financial assistance and support of Southeastern’s customers, funding for capitalized equipment purchases and replacements at hydroelectric facilities operated by the U.S. Army Corps of Engineers (Corps) continued in FY 2011. This funding, which totaled more than $45 million, provided much needed repairs and maintenance for aging projects in Southeastern’s marketing area. Currently, there are more than 214 customers participating in the funding efforts in the Georgia-Alabama-South Carolina, Kerr-Philpott, and Cumberland Systems of projects. Drought conditions continued in the southeastern region of the United States this past year, particularly in the Savannah River Basin. Lack of rain placed strains on our natural and financial resources. Power purchases for FY 2011 totaled approximately $38 million. About $9 million of this amount was for replacement power, which is purchased only during adverse water conditions in order to meet Southeastern’s customer contract requirements. Southeastern’s goal is to maximize the benefits of our region’s water resources. Competing uses of these resources will present another challenging year for Southeastern’s employees. With the cooperation and communication among the Department of Energy (DOE), preference customers, and Corps, I am certain Southeastern is positioned to meet these challenges in the future. We are committed to providing reliable hydroelectric power to

  12. Before and After Integrated Catchment Management in a Headwater Catchment: Changes in Water Quality

    NASA Astrophysics Data System (ADS)

    Hughes, Andrew O.; Quinn, John M.

    2014-12-01

    Few studies have comprehensively measured the effect on water quality of catchment rehabilitation measures in comparison with baseline conditions. Here we have analyzed water clarity and nutrient concentrations and loads for a 13-year period in a headwater catchment within the western Waikato region, New Zealand. For the first 6 years, the entire catchment was used for hill-country cattle and sheep grazing. An integrated catchment management plan was implemented whereby cattle were excluded from riparian areas, the most degraded land was planted in Pinus radiata, channel banks were planted with poplar trees and the beef cattle enterprise was modified. The removal of cattle from riparian areas without additional riparian planting had a positive and rapid effect on stream water clarity. In contrast, the water clarity decreased in those sub-catchments where livestock was excluded but riparian areas were planted with trees and shrubs. We attribute the decrease in water clarity to a reduction in groundcover vegetation that armors stream banks against preparatory erosion processes. Increases in concentrations of forms of P and N were recorded. These increases were attributed to: (i) the reduction of instream nutrient uptake by macrophytes and periphyton due to increased riparian shading; (ii) uncontrolled growth of a nitrogen fixing weed (gorse) in some parts of the catchment, and (iii) the reduction in the nutrient attenuation capacity of seepage wetlands due to the decrease in their areal coverage in response to afforestation. Our findings highlight the complex nature of the water quality response to catchment rehabilitation measures.

  13. 75 FR 65624 - Southeastern Power Administration; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southeastern Power Administration; Notice of Filing October 19, 2010. Take... Southeastern Power Administration (Southeastern) Rate Order No. SEPA- 53, for the sale of power...

  14. How old is upland catchment water?

    NASA Astrophysics Data System (ADS)

    Hofmann, Harald; Cartwright, Ian; Morgenstern, Uwe; Gilfedder, Benjamin

    2014-05-01

    Understanding the dynamics of water supply catchments is an essential part of water management. Upland catchments provide a continuous, reliable source of high quality water not only for some of the world's biggest cities, but also for agriculture and industry. Headwater streams control river flow in lowland agricultural basins as the majority of river discharge emerges from upland catchments. Many rivers are perennial and flow throughout the year, even during droughts. However, it is still unclear how reliable and continuous upland catchment water resources really are. Despite many efforts in upland catchment research, there is still little known about where the water is stored and how long it takes to travel through upper catchments. Resolving these questions is crucial to ensure that this resource is protected from changing land use and to estimate potential impacts from a changing climate. Previous research in this important area has been limited by existing measurement techniques. Knowledge to date has relied heavily on the use of variation in stable isotope signals to estimate the age and origin of water from upland catchments. The problem with relying on these measures is that as the water residence time increases, the variation in the stable isotope signal decreases. After a maximum period of four years, no variation can be detected This means that to date, the residence time in upland catchments is likely to have been vastly underestimated. Consequently, the proportion of water flow out of upland river catchments to the total river flow is also underestimated. Tritium (3H) combines directly with water molecules and enters the flow paths with the infiltrating water. Its half-life (12.32 years) makes it ideal to describe residence times in upper catchment reservoirs as it can theoretically measure water up to about 150 years old. The bomb pulse peak in the southern hemisphere was several orders of magnitude lower than in the northern hemisphere. Hence the

  15. Catchment scale multi-objective flood management

    NASA Astrophysics Data System (ADS)

    Rose, Steve; Worrall, Peter; Rosolova, Zdenka; Hammond, Gene

    2010-05-01

    Rural land management is known to affect both the generation and propagation of flooding at the local scale, but there is still a general lack of good evidence that this impact is still significant at the larger catchment scale given the complexity of physical interactions and climatic variability taking place at this level. The National Trust, in partnership with the Environment Agency, are managing an innovative project on the Holnicote Estate in south west England to demonstrate the benefits of using good rural land management practices to reduce flood risk at the both the catchment and sub-catchment scales. The Holnicote Estate is owned by the National Trust and comprises about 5,000 hectares of land, from the uplands of Exmoor to the sea, incorporating most of the catchments of the river Horner and Aller Water. There are nearly 100 houses across three villages that are at risk from flooding which could potentially benefit from changes in land management practices in the surrounding catchment providing a more sustainable flood attenuation function. In addition to the contribution being made to flood risk management there are a range of other ecosystems services that will be enhanced through these targeted land management changes. Alterations in land management will create new opportunities for wildlife and habitats and help to improve the local surface water quality. Such improvements will not only create additional wildlife resources locally but also serve the landscape response to climate change effects by creating and enhancing wildlife networks within the region. Land management changes will also restore and sustain landscape heritage resources and provide opportunities for amenity, recreation and tourism. The project delivery team is working with the National Trust from source to sea across the entire Holnicote Estate, to identify and subsequently implement suitable land management techniques to manage local flood risk within the catchments. These

  16. Southeastern Scarp of Olympus Mons

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 4 June 2002) The Science The movement pathways of molten rock, or lava, is demonstrated in this image of a portion of Olympus Mons, the largest volcano in our solar system. These now-solid lava flows all show nearly the same orientation, having flowed from northeast to southwest, down the slope of the volcano's southeastern flank. Throughout the image, narrow pairs of lineaments can be observed ? these are called levees, and are essentially channel walls formed by the solidification and buildup of the edges of the lava flows. We can determine that the high-standing mountains must be older than the flows because they blocked their passage, causing the flows to change direction and go around the taller mountains. As in other THEMIS images, the lack of bright-dark contrast in this image indicates that a layer of dust covers these surfaces. The surfaces of the lava flows are virtually uncratered, attesting to the relatively recent formation of the flows, where ?recent? is within the last 500 million years or so. Several meteorites found on Earth appear to have come from volcanic regions on Mars ? their ages are as young as 180 million years, leading many scientists to suggest that volcanoes of the Tharsis region, including Olympus Mons, may be the source regions of these meteorites. A prominent pear-shaped bowl is apparent on a hill in the lower right third of the image ? the collapse and mass movement of material down slope, which also formed a debris pile below and southeast of the bowl, likely formed this feature. The Story Millions and millions of years ago, a huge impact blasted a crater into the surface of Mars, sending particles of the Martian surface scattering into space at great speeds, where they spent millions and millions of years calmly in space before encountering a nearby orbiting planet: our own planet Earth. Hurtling down through Earth's atmosphere, these pieces of Mars landed in various regions of our world and were discovered by modern

  17. Southeastern Scarp of Olympus Mons

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 4 June 2002) The Science The movement pathways of molten rock, or lava, is demonstrated in this image of a portion of Olympus Mons, the largest volcano in our solar system. These now-solid lava flows all show nearly the same orientation, having flowed from northeast to southwest, down the slope of the volcano's southeastern flank. Throughout the image, narrow pairs of lineaments can be observed ? these are called levees, and are essentially channel walls formed by the solidification and buildup of the edges of the lava flows. We can determine that the high-standing mountains must be older than the flows because they blocked their passage, causing the flows to change direction and go around the taller mountains. As in other THEMIS images, the lack of bright-dark contrast in this image indicates that a layer of dust covers these surfaces. The surfaces of the lava flows are virtually uncratered, attesting to the relatively recent formation of the flows, where ?recent? is within the last 500 million years or so. Several meteorites found on Earth appear to have come from volcanic regions on Mars ? their ages are as young as 180 million years, leading many scientists to suggest that volcanoes of the Tharsis region, including Olympus Mons, may be the source regions of these meteorites. A prominent pear-shaped bowl is apparent on a hill in the lower right third of the image ? the collapse and mass movement of material down slope, which also formed a debris pile below and southeast of the bowl, likely formed this feature. The Story Millions and millions of years ago, a huge impact blasted a crater into the surface of Mars, sending particles of the Martian surface scattering into space at great speeds, where they spent millions and millions of years calmly in space before encountering a nearby orbiting planet: our own planet Earth. Hurtling down through Earth's atmosphere, these pieces of Mars landed in various regions of our world and were discovered by modern

  18. Validation of Pacific Northwest hydrologic landscapes at the catchment scale

    EPA Science Inventory

    The interaction between the physical properties of a catchment (form) and climatic forcing of precipitation and energy control how water is partitioned, stored, and conveyed through a catchment (function). Hydrologic Landscapes (HLs) were previously developed across Oregon and de...

  19. Grazed Riparian Management and Stream Channel Response in Southeastern Minnesota (USA) Streams

    NASA Astrophysics Data System (ADS)

    Magner, Joseph A.; Vondracek, Bruce; Brooks, Kenneth N.

    2008-09-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response.

  20. Grazed riparian management and stream channel response in southeastern Minnesota (USA) streams.

    PubMed

    Magner, Joseph A; Vondracek, Bruce; Brooks, Kenneth N

    2008-09-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response. PMID:18481141

  1. Vegetation History of Pleasant Island, Southeastern Alaska, since 13,000 yr B.P.

    NASA Astrophysics Data System (ADS)

    Hansen, Barbara C. S.; Engstrom, Daniel R.

    1996-09-01

    A 13,000-year history of late-Quaternary vegetational and climatic change has been derived from lacustrine sediments from Pleasant Island in the Glacier Bay region of southeastern Alaska. Early arrival of lodgepole pine and mountain hemlock, indicated by the presence of pollen and conifer stomata, suggests expansion from refugia in the Alexander Archipelago. A short-term climatic reversal, possibly correlated with the European Younger Dryas, is inferred from the expansion of tundra elements and deposition of inorganic sediments between 10,600 and 9900 14C yr B.P. Two peat cores from the lake catchment verify Holocene vegetation changes and aid in the separation of biogenic from climatic forces affecting vegetation history. Differences in pollen representation among the three cores illustrate the variation among pollen-collecting substrates, as well as the spatial heterogeneity of peatland development and its dependence on local hydrology. Initial peat accumulation and soil paludification, occasioned by increases in temperature and precipitation in the early Holocene, allowed western and mountain hemlock to replace sitka spruce 8500-8000 yr B. P. Open muskeg became widespread about 7000 yr B. P. and allowed lodgepole pine to reinvade the region after a 2000-yr absence. The extensive replacement of fen elements by bog taxa at 3400 yr B. P. suggests increased paludification due to changing hydrologic conditions; its correlation with the upland expansion of Tsuga heterophyllasuggests the onset of a cooler/wetter Neoglacial climate in southeastern Alaska.

  2. Characterizing streamflow generation in Alpine catchments

    NASA Astrophysics Data System (ADS)

    Chiogna, Gabriele; Cano Paoli, Karina; Bellin, Alberto

    2016-04-01

    Developing effective hydrological models for streamflow generation in Alpine catchments is challenging due to the inherent complexity of the intertwined processes controlling water transfer from hillslopes to streams and along the river network. With water discharge as the sole observational variable it is impossible to differentiate between different streamflow sources, and modelling activity is often limited to simplified phenomenological rainfall-runoff models. This study focuses on quantifying streamflow sources at different temporal scales and the associated uncertainty by using natural tracer data (electrical conductivity, oxygen and hydrogen stable isotopes ratios) as observational variables supplementing streamflow measurements. We determine the spatial and temporal hydrological behavior and the mean residence time of water in the Vermigliana catchment, North-Eastern Italy and we separate contributions to streamflow originating from Presena and Presanella glaciers, both exerting a strong control on the hydrologic budget of the study site. Furthermore, we identify a seasonal control on the effect of storm events. The catchment responded rapidly to precipitation events in early autumn, it was unaffected by precipitation events in early spring, while runoff generation was enhanced by snow melting in late autumn. Air temperature is identified as the main controlling parameter, in addition to precipitation. Two-component mixing analysis showed that the relative contribution of new water, which can contribute up to 75% of total streamflow, is very rapid. Only two hours time-lag was observed between the beginning of the precipitation event and the emergence of a significant contribution of new water. These results evidence the relevance of mixing between pre-event and event water in the Vermigliana catchment, and in similar high elevation Alpine catchments. This study provides new insights on the dynamics of streamflow generation in Alpine catchments and a

  3. Identification of internal flow dynamics in two experimental catchments

    USGS Publications Warehouse

    Hansen, D.P.; Jakeman, A.J.; Kendall, C.; Weizu, G.

    1997-01-01

    Identification of the internal flow dynamics in catchments is difficult because of the lack of information in precipitation -stream discharge time series alone. Two experimental catchments, Hydrohill and Nandadish, near Nanjing in China, have been set up to monitor internal flows reaching the catchment stream at various depths, from the surface runoff to the bedrock. With analysis of the precipitation against these internal discharges, it is possible to quantify the time constants and volumes associated with various flowpaths in both catchments.

  4. Picturing and modelling catchments by representative hillslopes

    NASA Astrophysics Data System (ADS)

    Loritz, Ralf; Hassler, Sibylle; Jackisch, Conrad; Zehe, Erwin

    2016-04-01

    Hydrological modelling studies often start with a qualitative sketch of the hydrological processes of a catchment. These so-called perceptual models are often pictured as hillslopes and are generalizations displaying only the dominant and relevant processes of a catchment or hillslope. The problem with these models is that they are prone to become too much predetermined by the designer's background and experience. Moreover it is difficult to know if that picture is correct and contains enough complexity to represent the system under study. Nevertheless, because of their qualitative form, perceptual models are easy to understand and can be an excellent tool for multidisciplinary exchange between researchers with different backgrounds, helping to identify the dominant structures and processes in a catchment. In our study we explore whether a perceptual model built upon an intensive field campaign may serve as a blueprint for setting up representative hillslopes in a hydrological model to reproduce the functioning of two distinctly different catchments. We use a physically-based 2D hillslope model which has proven capable to be driven by measured soil-hydrological parameters. A key asset of our approach is that the model structure itself remains a picture of the perceptual model, which is benchmarked against a) geo-physical images of the subsurface and b) observed dynamics of discharge, distributed state variables and fluxes (soil moisture, matric potential and sap flow). Within this approach we are able to set up two behavioral model structures which allow the simulation of the most important hydrological fluxes and state variables in good accordance with available observations within the 19.4 km2 large Colpach catchment and the 4.5 km2 large Wollefsbach catchment in Luxembourg without the necessity of calibration. This corroborates, contrary to the widespread opinion, that a) lower mesoscale catchments may be modelled by representative hillslopes and b) physically

  5. Modeling daily streamflow at ungauged catchments: What information is necessary?

    NASA Astrophysics Data System (ADS)

    Patil, S.; Stieglitz, M.

    2011-12-01

    Streamflow modeling at ungauged catchments involves transfer of information (viz., model structure and parameters) from gauged to ungauged catchments that are judged to be hydrologically similar. In this study, we focus on identifying: (1) what constitutes the critical information that needs to be transferred among hydrologically similar catchments to achieve good predictability using models at ungauged sites, and (2) which is the best approach for transferring this information from gauged to ungauged catchments. We develop a simple hydrologic model with minimal calibration requirement and implement it over 756 catchments located across the continental United States. The model computes water balance at a daily time-step and conceptualizes subsurface runoff through a storage-dependent exponential decline in saturated hydraulic conductivity. Snow accumulation and melt are modeled using the thermal degree-day concept. The calibrated model performs better in humid runoff-dominated regions than in the drier evapotranspiration-dominated regions. Results show that within a region, transfer of hydrograph recession information alone is sufficient for reliable streamflow predictions at ungauged catchments. Information transfer from spatially proximate gauged catchments provides better streamflow predictability at ungauged catchments than transfer from catchments identified as physically similar. When considering spatially proximate catchments, information transfer from multiple donor catchments is preferable to transfer from a single donor catchment.

  6. Insect destroyers of Tamarisk in southeastern Kazakhstan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This monograph contains the results of research work on the insect herbivores of tamarisk in southeastern Kazakhstan, which were conducted annually for last 12 years (1994-2006), and also the information, obtained by one of the authors (Mityaev) in the mid-1950s. Studies were conducted within the f...

  7. Emerging Energy Alternatives for the Southeastern States

    NASA Technical Reports Server (NTRS)

    Stefanakos, E. K. (Editor)

    1978-01-01

    The proceedings of the first symposium on emerging energy alternatives for the Southeastern States are presented. Some topics discussed are: (1) solar energy, (2) wood energy, (3) novel energy sources, (4) agricultural and industrial process heat, (5) waste utilization, (6) energy conservation and (7) ocean thermal energy conversion.

  8. Leading Change in Literacy: Southeastern District Stories.

    ERIC Educational Resources Information Center

    Bingham, C. Steven; Neal, Elizabeth Anne; Tesh, Linda; Turner, Patsy; Millsaps, Cherise

    Describing the SouthEastern Regional Vision for Education (SERVE) program and its mission to promote and support the continual improvement of educational opportunities for all learners in the Southeast, this paper focuses on the importance of improving student literacy outcomes in schools due to the demands of living in a technological,…

  9. Southeastern Europe: A Guide to Basic Publications.

    ERIC Educational Resources Information Center

    Horecky, Paul L., Ed.

    This annotated area guide presents a judicious evaluation of those writings which are particularly relevant to the contemporary political, socio-economic, and intellectual life of Southeastern Europe. It contains more than 3,000 bibliographic entries, together with additional citations for collateral reading. The entries include basic publications…

  10. Southeastern New Mexico Bilingual Program. Final Report.

    ERIC Educational Resources Information Center

    Lampman, Henry P.

    Academic growth and personal-social growth of 20 second grade children in the Southeastern New Mexico Bilingual Program at Artesia are compared to 20 second grade children in the standard program. The groups were matched by chronological and mental age, IQ, family income, family situation (both parents, only father, or only mother), number of…

  11. Water usage in southeastern bioenergy crop production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The southeastern United States with its long growing season and mild winter temperatures has long been able to produce a variety of food, forage, and fiber crops. In addition to these crops, the Southeast is capable of producing a plethora of lignoceullosic-based bioenergy crops for conversion into ...

  12. SOIL CHANGE IN SOUTHEASTERN USA ULTISOLS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Documentation of soil change due to management is needed to improve soil survey map unit interpretations and for population of resource databases. The southeastern US is a vital region for documenting soil change due to intensive cultivation and utilization of soil resources, dynamic land management...

  13. Southeastern Library Network (SOLINET) General Information.

    ERIC Educational Resources Information Center

    Southeastern Library Network, Inc., Atlanta, GA.

    The computer and telecommunications services of the Southeastern Library Network (SOLINET) are specified in this introduction to the Network. Since members of SOLINET may participate in the services of the Ohio College Library Center (OCLC), a description of these services is included. Membership requirements, fees and dues, and charges to SOLINET…

  14. Southeastern Community College Strategic Plan, August 1996.

    ERIC Educational Resources Information Center

    Southeastern Community Coll., West Burlington, IA.

    This report highlights a 1996 strategic plan developed by Southeastern Community College (SCC), in Iowa, after an exhaustive review of an existing plan and the identification of new institutional goals. Following SCC's educational philosophy statement, mission statement, and definitions of terms, the plan provides charts of SCC strengths and areas…

  15. Global investigation of vegetation impact on mean annual catchment evapotranspiration

    NASA Astrophysics Data System (ADS)

    Peel, Murray C.; McMahon, Thomas A.; Finlayson, Brian L.

    2010-05-01

    Historically, relationships between catchment vegetation type, evapotranspiration and runoff have been assessed primarily through paired catchment studies. The literature contains results from over 200 of these studies from around the world but two factors limit the applicability of the results to the wider domain. Firstly, catchment areas are generally small (<10 km2). Secondly, the range of climate types is narrow, with temperate (Köppen C) and cold (Köppen D) climate types in the majority. Here we present results from a global assessment of the impact of vegetation type on mean annual catchment evapotranspiration for a large, spatially and climatically diverse dataset of 699 catchments. This assessment is based on analysis of areal precipitation, temperature, runoff, and land cover information from each catchment, which differs from the paired catchment methodology where streamflow responses to a controlled land cover change are assessed. When catchments are grouped by vegetation type, any evidence of differing vegetation impact on actual evapotranspiration will be observed through differences in mean annual actual evapotranspiration, defined as precipitation minus runoff. Stratifying catchments by climate type was observed to be important when assessing the vegetation impact on evapotranspiration. Tropical and temperate forested catchments had significantly higher median evapotranspiration (~170mm and ~130mm, respectively) than non-forested catchments. Cold forested catchments unexpectedly had significantly lower median evapotranspiration (~90mm) than non-forested catchments. No significant difference in median evapotranspiration was found between temperate evergreen and deciduous forested catchments, though sample sizes were small. Temperate evergreen needleleaf forested catchments had significantly higher median evapotranspiration than evergreen broadleaf forested catchments, though again sample sizes were small. The significant difference in median

  16. Soil depth and topography: a field assessment of evolutionary controls in a small catchment

    NASA Astrophysics Data System (ADS)

    Hancock, Greg; Willgoose, Garry; Cohen, Sagy

    2015-04-01

    Soil depth is the difference between soil production and soil erosion. Given uniform soil properties, soil depth limits the water storage capacity of a soil and therefore controls soil biological productivity. It is generally believed that soil depth varies down a hillslope and according to the catena concept and is shallow at the hillslope crest and deepest at the footslope. However, soil depth is a notoriously difficult hillslope feature to quantify. Globally there is a paucity of catchment scale soil depth data. Here soil depth was measured in a small 7.5 ha catchment (Stanley Jr) with basalt derived soils in south-eastern Australia. Depth was measured at regular 25m spacings using a petrol-powered auger to point of refusal. A Global Positioning Unit (GPS) was used to locate coordinates for each measurement. Soil depth was found to be shallower at the top of the catchment and increased moving downslope following the catena concept. Depth ranged from a minimum of 0.05 m to a maximum soil depth of 2 m, with an average soil depth of 0.44m and median of 0.22m. Soil depth was found to be correlated with elevation. However, no significant relationship was found between soil depth and surface slope or soil depth and upslope contributing area. No relationship was found between soil depth and topographic wetness indices. The soil depth data was used to produce a bedrock DEM. Examination of the bedrock topography showed that similar to the surface topography findings, there was no relationship between bedrock slope or bedrock upslope contributing area and soil depth but a statistically significant relationship was found between bedrock elevation and topographic wetness indices. This suggests that subsurface hydrology and soil moisture play a significant role in pedogenesis and are decoupled from surface topography.

  17. Catchment-scale Richards equation-based modeling of evapotranspiration via boundary condition switching and root water uptake schemes

    NASA Astrophysics Data System (ADS)

    Camporese, Matteo; Daly, Edoardo; Paniconi, Claudio

    2015-07-01

    In arid and semiarid climate catchments, where annual evapotranspiration (ET) and rainfall are typically comparable, modeling ET is important for proper assessment of water availability and sustainable land use management. The aim of the present study is to assess different parsimonious schemes for representing ET in a process-based model of coupled surface and subsurface flow. A simplified method for computing ET based on a switching procedure for the boundary conditions of the Richards equation at the soil surface is compared to a sink term approach that includes root water uptake, root distribution, root water compensation, and water and oxygen stress. The study site for the analysis is a small pasture catchment in southeastern Australia. A comprehensive sensitivity analysis carried out on the parameters of the sink term shows that the maximum root depth is the dominant control on catchment-scale ET and streamflow. Comparison with the boundary condition switching method demonstrates that this simpler scheme (only one parameter) can successfully reproduce ET when the vegetation root depth is shallow (not exceeding approximately 50 cm). For deeper rooting systems, the switching scheme fails to match the ET fluxes and is affected by numerical artifacts, generating physically unrealistic soil moisture dynamics. It is further shown that when transpiration is the dominant contribution to ET, the inclusion of oxygen stress and root water compensation in the model can have a considerable effect on the estimation of both ET and streamflow; this is mostly due to the water fluxes associated with the riparian zone.

  18. Southeastern Power Administration 2008 Annual Report

    SciTech Connect

    2008-12-29

    Dear Secretary Chu: I am pleased to submit Southeastern Power Administration’s (Southeastern’s) fiscal year (FY) 2008 Annual Report for your review. The information included in this document reflects our agency’s programs, accomplishments, operational and financial activities for the 12-month period beginning October 1, 2007 and ending September 30, 2008. Southeastern marketed more than 4.5 billion kilowatt-hours of energy to 491 wholesale customers in ten southeastern states this past year. Revenues from the sale of this power totaled approximately $263 million. Drought conditions persisted in the southeastern region of the United States during FY 2008 placing strains on our natural and financial resources. Power purchases for FY 2008 totaled $91 million. Approximately $44 million of this amount was for replacement power which is paid only during adverse water conditions in order to meet our customers’ contract requirements. With the continued financial assistance and support of our Federal power customers, funding for capitalized equipment purchases and replacements at U.S. Army Corps of Engineers’ (Corps) hydroelectric projects provided much needed repairs and maintenance for these aging facilities. Southeastern’s cyber and physical security programs continued to be reviewed and updated to meet Department of Energy (DOE), Homeland Security, and North American Electric Reliability Corporation (NERC) standards and requirements. In the coming year, Southeastern will continue open communication and cooperation with DOE, the Federal power customers, and the Corps to maximize the benefits of our region’s water resources. Although competing uses of water and the prolonged drought conditions will present another challenging year for our agency, Southeastern’s employees will meet these challenges and continue to provide reliable hydroelectric power to the people in the southeast. Sincerely, Kenneth E.Legg Administrator

  19. Automatic interpretation of MSS-LANDSAT data applied to coal refuse site studies in southern Santa Catarina State, Brazil

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Kux, H. J. H.; Valeriano, D. D. M.

    1982-01-01

    The coal mining district in southeastern Santa Catarina State is considered one of the most polluted areas of Brazil. The author has identified significant preliminary results on the application of MSS-LANDSAT digital data to monitor the coal refuse areas and its environmental consequences in this region.

  20. Towards a Political Ecology of Education: The Educational Politics of Scale in Southern Pará, Brazil

    ERIC Educational Resources Information Center

    Meek, David

    2015-01-01

    Social movements have initiated both academic programs and disciplines. I present ethnographic data that I gathered during 17 months of fieldwork with the Brazilian Landless Workers' Movement (MST) in southeastern Pará, Brazil, to explore the MST's role in creating agroecological education opportunities. My analysis highlights three factors in…

  1. Co-evolution of volcanic catchments in Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, T.; Troch, P. A.

    2015-09-01

    Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma) in Japan. We derived indices of landscape properties (drainage density) as well as hydrological response (annual water balance, baseflow index, and flow duration curves) and examined their relation with catchment age and climate (through the aridity index). We found significant correlation between drainage density and baseflow index with age, but not with climate. The age of the catchments was also significantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of significant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggests two hypotheses on the evolution of drainage density in matured catchments. One is that as catchments further evolve

  2. Ecosystem Services Derived from Headwater Catchments

    EPA Science Inventory

    We used data from the USEPA’s wadeable streams assessment (WSA), US Forest Service’s forest inventory and analysis (FIA), and select USFS experimental forests (EF) to investigate potential ecosystems services derived from headwater catchments. C, N, and P inputs to these catchmen...

  3. Geomorphic histories for river and catchment management.

    PubMed

    Wasson, R J

    2012-05-13

    River and catchment management usually proceeds from the identification of an undesirable state (e.g. pollution, sedimentation, excessive water extraction, dams, invasion by exotic species) to a strategy for reaching a desirable state described as a target. Desirable states are usually determined from community values, economic assessments and ecosystem functions, or a combination of these. Where a catchment is highly disturbed, the target is usually not a natural state, as that cannot be achieved while maintaining human uses, and a history is needed to document the disturbance, understand its cause and define the 'existence space', that is, the range of natural states that have occurred in the past. Where a catchment is less disturbed, a former natural state could provide a target for management. But which of the many natural (equilibrium) states that have occurred in the past should be the target? The paper reviews what is known of the quantitative difference between pre- and post-disturbance states, searches for the presence or otherwise of equilibrium and comments on the utility of this information for catchment management. The focus is on erosion and sediment transport. PMID:22474683

  4. Measuring winter precipitation in a mountain catchment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Measuring winter precipitation (principally snowfall) in a mountain catchment is difficult. The magnitude of gauge under catch is affected by variable density during deposition, wind speed and direction, and site conditions such as vegetation and topography. Though numerous studies have been condu...

  5. Catchment management and the Great Barrier Reef.

    PubMed

    Brodie, J; Christie, C; Devlin, M; Haynes, D; Morris, S; Ramsay, M; Waterhouse, J; Yorkston, H

    2001-01-01

    Pollution of coastal regions of the Great Barrier Reef is dominated by runoff from the adjacent catchment. Catchment land-use is dominated by beef grazing and cropping, largely sugarcane cultivation, with relatively minor urban development. Runoff of sediment, nutrients and pesticides is increasing and for nitrogen is now four times the natural amount discharged 150 years ago. Significant effects and potential threats are now evident on inshore reefs, seagrasses and marine animals. There is no effective legislation or processes in place to manage agricultural pollution. The Great Barrier Reef Marine Park Act does not provide effective jurisdiction on the catchment. Queensland legislation relies on voluntary codes and there is no assessment of the effectiveness of the codes. Integrated catchment management strategies, also voluntary, provide some positive outcomes but are of limited success. Pollutant loads are predicted to continue to increase and it is unlikely that current management regimes will prevent this. New mechanisms to prevent continued degradation of inshore ecosystems of the Great Barrier Reef World Heritage Area are urgently needed. PMID:11419129

  6. Catchment scale afforestation for mitigating flooding

    NASA Astrophysics Data System (ADS)

    Barnes, Mhari; Quinn, Paul; Bathurst, James; Birkinshaw, Stephen

    2016-04-01

    After the 2013-14 floods in the UK there were calls to 'forest the uplands' as a solution to reducing flood risk across the nation. At present, 1 in 6 homes in Britain are at risk of flooding and current EU legislation demands a sustainable, 'nature-based solution'. However, the role of forests as a natural flood management technique remains highly controversial, due to a distinct lack of robust evidence into its effectiveness in reducing flood risk during extreme events. SHETRAN, physically-based spatially-distributed hydrological models of the Irthing catchment and Wark forest sub-catchments (northern England) have been developed in order to test the hypothesis of the effect trees have on flood magnitude. The advanced physically-based models have been designed to model scale-related responses from 1, through 10, to 100km2, a first study of the extent to which afforestation and woody debris runoff attenuation features (RAFs) may help to mitigate floods at the full catchment scale (100-1000 km2) and on a national basis. Furthermore, there is a need to analyse the extent to which land management practices, and the installation of nature-based RAFs, such as woody debris dams, in headwater catchments can attenuate flood-wave movement, and potentially reduce downstream flood risk. The impacts of riparian planting and the benefits of adding large woody debris of several designs and on differing sizes of channels has also been simulated using advanced hydrodynamic (HiPIMS) and hydrological modelling (SHETRAN). With the aim of determining the effect forestry may have on flood frequency, 1000 years of generated rainfall data representative of current conditions has been used to determine the difference between current land-cover, different distributions of forest cover and the defining scenarios - complete forest removal and complete afforestation of the catchment. The simulations show the percentage of forestry required to have a significant impact on mitigating

  7. Inferring the effect of catchment complexity on mesoscale hydrologic response

    NASA Astrophysics Data System (ADS)

    FröHlich, Holger L.; Breuer, Lutz; Vaché, Kellie B.; Frede, Hans-Georg

    2008-09-01

    The effect of catchment complexity on hydrologic and hydrochemical catchment response was characterized in the mesoscale Dill catchment (692 km2), Germany. This analysis was developed using multivariate daily stream concentration and discharge data at the basin outlet, in connection with less frequently sampled catchment-wide end-member chemistries. The link between catchment-wide runoff sources and basin output was observed through a combination of concentration-discharge (C-Q) analysis and multivariate end-member projection. Subsurface stormflow, various groundwater and wastewater sources, as well as urban surface runoff emerged in catchment output chemistry. Despite the identification of multiple sources, several runoff sources observed within the catchment failed to display consistent links with the output chemistry. This failure to associate known source chemistry with outlet chemistry may have resulted from a lack of hydraulic connectivity between sources and basin outlet, from different arrival times of subbasin-scale runoff contributions, and also from an overlap of source chemistries that subsumed discrete runoff sources in catchment output. This combination of catchment heterogeneity and complexity simply suggests that the internal spatial organization of the catchment impeded the application of lumped mixing calculations at the 692 km2 outlet. Given these challenges, we suggest that in mesoscale catchment research, the potential effects of spatial organization should be included in any interpretation of highly integrated response signals, or when using those signals to evaluate numerical rainfall-runoff models.

  8. Physics-based simulation of surface and near-surface hydrologic response for the Tarrawarra Catchment: parameterization for a synthetic dataset

    NASA Astrophysics Data System (ADS)

    Mirus, B. B.; Loague, K.; Kampf, S. K.; Burges, S. J.

    2007-12-01

    Comprehensive physics-based simulation is a useful tool for furthering our understanding of complex hydrologic- response processes. The first step to using hypothetical realities as a base-case for concept development and hypothesis testing, is to confirm that the model / boundary-value problem (BVP) is capable of realistically representing known hydrologic-response processes. This study presents the development of a synthetic dataset designed to emulate the Tarrawarra Catchment (Southeastern Australia) using the physics-based, Integrated Hydrology Model (InHM). The Tarrawarra Catchment is a 10.5 ha, unchanneled rangeland catchment, with gentle slopes; runoff generation is dominated by the Dunne overland flow mechanism. The Tarrawarra BVP was parameterized based on topography and observed soil characteristics, then calibrated for a six month period in 1996 during which there exist continuous records of rainfall, potential evapotranspiration, and surface runoff, as well as episodic sampling of soil-water content and piezometric head distributed through out the catchment. While in practice no simulation could ever incorporate all the intricacies present at the Tarrawarra Catchment, the simulations conducted for this study honor both the observations and our best understanding of the physics governing near-surface hydrologic response. The simulations show that runoff occurs only after the locally perched water table rises to the land surface, in agreement with observations at Tarrawarra. Quantitative comparison of observed and simulated hydrologic-response also shows that the model accurately captures both the integrated response (surface discharge) and the distributed response (pressure head and soil-water content), supporting the use of InHM to generate synthetic response data for a Tarrawarra-like catchment. The continuous simulations have the added advantage of greater spatial and temporal resolution than any comprehensive dataset, allowing further insight into

  9. Regional assessment of pumpage in southeastern Virginia

    USGS Publications Warehouse

    Hamilton, Pixie A.

    1988-01-01

    A U.S. Geological Survey investigation was conducted, in cooperation with the Virginia Water Control Board, to analyze the hydrogeology and groundwater flow system in the Coastal Plain physiographic province of southeastern Virginia, and to assess the continued reliability of groundwater as a freshwater resource. To provide a more detailed analysis of water-level decline and groundwater flow, a three-dimensional, digital, groundwater flow model, which incorporates hydrogeologic characteristics of the aquifers and confining units, was developed to simulate prepumping and pumping conditions. The results of this modeling effort provide a broad regional perspective on the magnitude and direction of groundwater flow in the confined system in the Coastal Plain physiographic province of southeastern Virginia.

  10. Inverse distributed hydrological modelling of alpine catchments

    NASA Astrophysics Data System (ADS)

    Kunstmann, H.; Krause, J.; Mayr, S.

    2005-12-01

    Even in physically based distributed hydrological models, various remaining parameters must be estimated for each sub-catchment. This can involve tremendous effort, especially when the number of sub-catchments is large and the applied hydrological model is computationally expensive. Automatic parameter estimation tools can significantly facilitate the calibration process. Hence, we combined the nonlinear parameter estimation tool PEST with the distributed hydrological model WaSiM. PEST is based on the Gauss-Marquardt-Levenberg method, a gradient-based nonlinear parameter estimation algorithm. WaSiM is a fully distributed hydrological model using physically based algorithms for most of the process descriptions. WaSiM was applied to the alpine/prealpine Ammer River catchment (southern Germany, 710 km2) in a 100×100 m2 horizontal resolution. The catchment is heterogeneous in terms of geology, pedology and land use and shows a complex orography (the difference of elevation is around 1600 m). Using the developed PEST-WaSiM interface, the hydrological model was calibrated by comparing simulated and observed runoff at eight gauges for the hydrologic year 1997 and validated for the hydrologic year 1993. For each sub-catchment four parameters had to be calibrated: the recession constants of direct runoff and interflow, the drainage density, and the hydraulic conductivity of the uppermost aquifer. Additionally, five snowmelt specific parameters were adjusted for the entire catchment. Altogether, 37 parameters had to be calibrated. Additional a priori information (e.g. from flood hydrograph analysis) narrowed the parameter space of the solutions and improved the non-uniqueness of the fitted values. A reasonable quality of fit was achieved. Discrepancies between modelled and observed runoff were also due to the small number of meteorological stations and corresponding interpolation artefacts in the orographically complex terrain. A detailed covariance analysis was performed

  11. Inverse distributed hydrological modelling of Alpine catchments

    NASA Astrophysics Data System (ADS)

    Kunstmann, H.; Krause, J.; Mayr, S.

    2006-06-01

    Even in physically based distributed hydrological models, various remaining parameters must be estimated for each sub-catchment. This can involve tremendous effort, especially when the number of sub-catchments is large and the applied hydrological model is computationally expensive. Automatic parameter estimation tools can significantly facilitate the calibration process. Hence, we combined the nonlinear parameter estimation tool PEST with the distributed hydrological model WaSiM. PEST is based on the Gauss-Marquardt-Levenberg method, a gradient-based nonlinear parameter estimation algorithm. WaSiM is a fully distributed hydrological model using physically based algorithms for most of the process descriptions. WaSiM was applied to the alpine/prealpine Ammer River catchment (southern Germany, 710 km2 in a 100×100 m2 horizontal resolution. The catchment is heterogeneous in terms of geology, pedology and land use and shows a complex orography (the difference of elevation is around 1600 m). Using the developed PEST-WaSiM interface, the hydrological model was calibrated by comparing simulated and observed runoff at eight gauges for the hydrologic year 1997 and validated for the hydrologic year 1993. For each sub-catchment four parameters had to be calibrated: the recession constants of direct runoff and interflow, the drainage density, and the hydraulic conductivity of the uppermost aquifer. Additionally, five snowmelt specific parameters were adjusted for the entire catchment. Altogether, 37 parameters had to be calibrated. Additional a priori information (e.g. from flood hydrograph analysis) narrowed the parameter space of the solutions and improved the non-uniqueness of the fitted values. A reasonable quality of fit was achieved. Discrepancies between modelled and observed runoff were also due to the small number of meteorological stations and corresponding interpolation artefacts in the orographically complex terrain. Application of a 2-dimensional numerical

  12. Establishing a connection between hydrologic model parameters and physical catchment signatures for improved hierarchical Bayesian modeling in ungauged catchments

    NASA Astrophysics Data System (ADS)

    Marshall, L. A.; Weber, K.; Smith, T. J.; Greenwood, M. C.; Sharma, A.

    2012-12-01

    In an effort to improve hydrologic analysis in areas with limited data, hydrologists often seek to link catchments where little to no data collection occurs to catchments that are gauged. Various metrics and methods have been proposed to identify such relationships, in the hope that "surrogate" catchments might provide information for those catchments that are hydrologically similar. In this study we present a statistical analysis of over 150 catchments located in southeast Australia to examine the relationship between a hydrological model and certain catchment metrics. A conceptual rainfall-runoff model is optimized for each of the catchments and hierarchical clustering is performed to link catchments based on their calibrated model parameters. Clustering has been used in recent hydrologic studies but catchments are often clustered based on physical characteristics alone. Usually there is little evidence to suggest that such "surrogate" data approaches provide sufficiently similar model predictions. Beginning with model parameters and working backwards, we hope to establish if there is a relationship between the model parameters and physical characteristics for improved model predictions in the ungauged catchment. To analyze relationships, permutational multivariate analysis of variance tests are used that suggest which hydrologic metrics are most appropriate for discriminating between calibrated catchment clusters. Additional analysis is performed to determine which cluster pairs show significant differences for various metrics. We further examine the extent to which these results may be insightful for a hierarchical Bayesian modeling approach that is aimed at generating model predictions at an ungauged site. The method, known as Bayes Empirical Bayes (BEB) works to pool information from similar catchments to generate informed probability distributions for each model parameter at a data-limited catchment of interest. We demonstrate the effect of selecting

  13. Biochemical Education in Brazil.

    ERIC Educational Resources Information Center

    Vella, F.

    1988-01-01

    Described are discussions held concerning the problems of biochemical education in Brazil at a meeting of the Sociedade Brazileira de Bioquimica in April 1988. Also discussed are other visits that were made to universities in Brazil. Three major recommendations to improve the state of biochemistry education in Brazil are presented. (CW)

  14. Effects of climate change on southeastern forests

    USGS Publications Warehouse

    Harcombe, Paul A.

    1997-01-01

    Forests of the coastal plain region of the southeastern United States are among the most productive in North America. Because they form the basis of a large timber and wood products industry, these forests are of considerable economic importance. Also, the forests are rich in plant and animal species. Because they are diverse as well as productive, they have considerable conservation importance. Therefore, understanding potential impacts of climate change on southern forests is critical.

  15. Southeastern Power Administration 2007 Annual Report

    SciTech Connect

    2007-12-28

    Dear Secretary Chu: I am proud to submit Southeastern Power Administration’s (Southeastern’s) fiscal year (FY) 2007 Annual Report for your review. The information included in this report reflects Southeastern’s programs, accomplishments, and financial activities for the 12-month period beginning October 1, 2006 and ending September 30, 2007. Southeastern marketed more than 5 billion kilowatt-hours of energy to 492 wholesale Federal power customers in an 11-state marketing area in FY 2007. Revenues from the sale of this power totaled approximately $219 million. Drought conditions continued to plague the southeast region of the United States during 2007 placing strains on our natural and financial resources. Southeastern purchased more than $40 million in replacement power to meet customer contract requirements to ensure the continued reliability of our nation’s power grid. With the financial assistance and support of our Federal power customers, continued funding for capitalized equipment replacements at various Corps of Engineers’ (Corps) hydroelectric projects provided much needed repairs and maintenance for aging facilities. Southeastern’s cyber and physical security program continued to be reviewed and updated to meet Department of Energy (DOE), Homeland Security, and North American Electric Reliability Corporation standards and requirements. Plans for the upcoming year include communication and cooperation with DOE, Federal power customers, and the Corps to maximize the benefits of our nation’s water resources. Competition for the use of water and the prolonged drought conditions will present another challenging year for our agency. The employees at Southeastern will be proactive in meeting these challenges and providing reliable hydroelectric power to the people in the southeast. Sincerely, Kenneth E. Legg Administrator

  16. Post-fire water quality in forest catchments: a review with implications for potable water supply

    NASA Astrophysics Data System (ADS)

    Smith, Hugh; Sheridan, Gary; Lane, Patrick; Nyman, Petter; Haydon, Shane

    2010-05-01

    In many locations fire-prone forest catchments are utilised for the supply of potable water to small communities up to large cities. For example, in south-eastern Australia, wildfires have burned part or all of forest catchments supplying drinking water to Sydney (2001 wildfire), Canberra (2003), Adelaide (2007), Melbourne (2009), as well as various regional towns. Generally, undisturbed forest catchments are a source of high quality water. However, increases in erosion and sediment flux, runoff generation, and changes to the supply of key constituents after wildfire may result in contamination of water supplies. In this review, we present key physical and chemical constituents from a drinking water perspective that may be generated in burned forest catchments and examine post-fire changes to concentrations of these constituents in streams and reservoirs. The World Health Organisation (WHO) drinking water guideline values were used to assess reported post-fire constituent concentrations. Constituents examined include suspended sediment, ash, nutrients, trace metals, anions (Cl-, SO42-), cyanides, and polycyclic aromatic hydrocarbons (PAHs). Constituent concentrations in streams and reservoirs vary substantially following wildfire. In streams, maximum reported total suspended solid concentrations (SSC) in the first year after fire ranged from 11 to 143,000 mg L-1. SSC is often measured in studies of post-fire stream water quality, whereas turbidity is used in drinking water guidelines and more commonly monitored in water supply reservoirs. For burned catchment reservoirs in south-eastern Australia, peak turbidities increased over pre-fire conditions, as did the frequency of exceedance of the turbidity guideline. NO3-, NO2-, and NH4+ may increase after wildfire but maximum recorded concentrations have not exceeded WHO guideline values. Large post-fire increases in total N and total P concentrations in streams and reservoirs have been observed, although there are no

  17. Runoff generation mechanism at two distinct headwater catchments - isotopic evidence

    NASA Astrophysics Data System (ADS)

    Dohnal, Michal; Votrubová, Jana; Šanda, Martin; Tesař, Miroslav; Vogel, Tomáš; Dušek, Jaromír

    2016-04-01

    Data from two headwater catchments indicate considerably different runoff formation mechanisms. The contributions of different surface and subsurface runoff mechanisms to the catchment discharge formation at these two small forested headwater catchments are studied with help of the natural isotopic signatures of the observed fluxes. The Uhlirska catchment (1.78 sq. km, Jizera Mts., Czech Republic) is situated in headwater area of Cerna Nisa stream. Deluviofluvial granitic sediments in the valley bottom areas (riparian zones/wetlands) are surrounded by gentle hillslopes with shallow soils developed on crystalline bedrock. The Liz catchment (0.99 sq. km, Bohemian Forest, Czech Republic) belongs to hillslope-type catchments without riparian zones situated in headwater area of Volynka River. The soil at Liz is developed on biotite paragneiss bedrock. Autocorrelation analysis of the measured catchment discharge rates reveals different hydrograph characteristics for each of the two catchments. Estimated autocorrelation lengths differ by an order of magnitude. Variations of oxygen-18 isotope concentrations in precipitation, groundwater and streamflow were analyzed. Several significant rainfall-runoff events at each of the two catchments were analyzed in detail. These events exhibit substantial difference in isotopic compositions of event and pre-event water, which facilitates hydrograph separation. Clockwise and counterclockwise hysteretic relationships between the stream discharge and its isotope concentration were identified. Results were confronted with the previously published concepts of the runoff formation at the catchments under study. The research was funded by the Czech Science Foundation, project No. 14-15201J.

  18. Downward approach at the catchment scale or at the catchment set scale?

    NASA Astrophysics Data System (ADS)

    Perrin, C.; Andréassian, V.; Le Moine, N.

    2009-04-01

    The downward approach that learns from observations the main features of the catchment hydrological response has long been recognized as a way to develop hydrological models for the catchment scale (Klemes, 1983). In this approach, a link is made between rainfall inputs and flow outputs using the mathematical tools found the most efficient to reproduce catchment behaviour. This approach received recently more attention, as some limitations of the upward approach were identified (Sivapalan et al., 2003). However model structures developed with this downward approach at the catchment scale are often difficult to generalize, i.e. difficult to transpose to other catchments. Indeed they are often over-adapted to the specific features of the catchment on which they were developed. Generalization is a major problem in current hydrological modelling (Sivakumar, 2008). This is potentially a major drawback for the application of such models to the case of ungauged catchments. We argue that a better way to develop the structure of hydrological models following a downward approach is to place model development at the level of large set of catchments and not only at the level of a single catchment. This way of developing models will force them to be general, i.e. more transposable in space. They will capture the essential features of the rainfall-runoff transformation common between catchments. This way of developing models also gives the opportunity to analyse the spatial patterns of model failures, therefore providing more robust sources of explanations and more convincing ways to improve models. We do not believe that we could develop a single model that fit all conditions, but models developed with this approach are likely to be better starting points to get general models. Then we have to find ways to make them more appropriate to specific conditions without losing their generality. We will illustrate the advantages (and possible limitations) of this approach using

  19. Co-evolution of volcanic catchments in Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, T.; Troch, P. A. A.

    2015-12-01

    Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.22 to 82Ma) in Japan. We derived indices of landscape properties (drainage density) as well as hydrological response (annual water balance, baseow index, and flow duration curves) and examined their relation with catchment age and climate (through the aridity index). We found signicant correlation between drainage density and baseow index with age, but not with climate. The age of the catchments was also signicantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of signicant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggest that as catchments further evolve, hydrologically active channels retreat as less recharge leads to lower average aquifer levels

  20. Catchment Engineering: A New Paradigm in Water Management

    NASA Astrophysics Data System (ADS)

    Quinn, P. F.; Burke, S.; O'Donnell, G. M.; Wilkinson, M.; Jonczyk, J.; Barber, N.; Nicholson, A.; Proactive Team

    2011-12-01

    Recent catchment initiatives have highlighted the need for new holistic approaches to sustainable water management. Here, a catchment engineering approach seeks to describe catchment 'function' (or role) as the principal driver for evaluating how it should be managed in the future. Catchment engineering does not seek to re-establish a natural system but seeks to work with natural processes in order to engineer landscapes so that multiple benefits accrue. This approach involves quantifying and assessing catchment change and impacts but most importantly suggests an urgent and proactive agenda for future planning. In particular, an interventionist approach to managing hydrological flow pathways across scale is proposed. It is already accepted that future management will require a range of scientific expertise and full engagement with stakeholders, namely the general public and policy makers. This inclusive concept under a catchment engineering agenda forces any consortia to commit to actively changing and perturbing the catchment system and thus learn, in situ, how to manage the environment for collective benefits. The shared cost, the design, the implementation, the evaluation and any subsequent modifications should involve all relevant parties in the consortia. This joint ownership of a 'hands on' interventionist agenda to catchment change is at the core of catchment engineering. In this paper we show a range of catchment engineering projects from the UK that have addressed multi-disciplinary approaches to flooding, pollution and ecosystem management whilst maintaining economic food production. Local scale demonstration activities, led by local champions, have proven to be an effective means of encouraging wider uptake. Catchment engineering is a concept that relies on all relevant parties within a catchment to take responsibility for the water quantity and quality that arises from the catchment. Further, any holistic solution requires a bottom up, problem solving

  1. Angiostrongylus cantonensis and rat lungworm disease in Brazil.

    PubMed

    Thiengo, Silvana Carvalho; Simões, Raquel de Oliveira; Fernandez, Monica Ammon; Maldonado, Arnaldo

    2013-06-01

    The metastrongyloid nematode genus Angiostrongylus includes 18 species, two of which are relevant from a medical standpoint, Angiostrongylus costaricensis and Angiostrongylus cantonensis. The first was described from Costa Rica in 1971 and causes abdominal angiostrongyliasis in the Americas, including in Brazil. Angiostrongylus cantonensis, first described in 1935 from Canton, China, is the causative agent of eosinophilic meningitis. The natural definitive hosts are rodents, and molluscs are the intermediate hosts. Paratenic or carrier hosts include crabs, freshwater shrimp, amphibians, flatworms, and fish. Humans become infected accidentally by ingestion of intermediate or paratenic hosts and the parasite does not complete the life cycle as it does in rats. Worms in the brain cause eosinophilic meningitis. This zoonosis, widespread in Southeast Asia and the Pacific islands, has now been reported from other regions. In the Americas there are records from the United States, Cuba, Jamaica, Brazil, Ecuador, and Haiti. In Brazil seven human cases have been reported since 2007 from the southeastern and northeastern regions. Epidemiological studies found infected specimens of Rattus norvegicus and Rattus rattus as well as many species of molluscs, including the giant African land snail, Achatina fulica, from various regions of Brazil. The spread of angiostrongyliasis is currently a matter of concern in Brazil. PMID:23901376

  2. Potential Geographic Distribution of Hantavirus Reservoirs in Brazil

    PubMed Central

    de Oliveira, Stefan Vilges; Escobar, Luis E.; Peterson, A. Townsend; Gurgel-Gonçalves, Rodrigo

    2013-01-01

    Hantavirus cardiopulmonary syndrome is an emerging zoonosis in Brazil. Human infections occur via inhalation of aerosolized viral particles from excreta of infected wild rodents. Necromys lasiurus and Oligoryzomys nigripes appear to be the main reservoirs of hantavirus in the Atlantic Forest and Cerrado biomes. We estimated and compared ecological niches of the two rodent species, and analyzed environmental factors influencing their occurrence, to understand the geography of hantavirus transmission. N. lasiurus showed a wide potential distribution in Brazil, in the Cerrado, Caatinga, and Atlantic Forest biomes. Highest climate suitability for O. nigripes was observed along the Brazilian Atlantic coast. Maximum temperature in the warmest months and annual precipitation were the variables that most influence the distributions of N. lasiurus and O. nigripes, respectively. Models based on occurrences of infected rodents estimated a broader area of risk for hantavirus transmission in southeastern and southern Brazil, coinciding with the distribution of human cases of hantavirus cardiopulmonary syndrome. We found no demonstrable environmental differences among occurrence sites for the rodents and for human cases of hantavirus. However, areas of northern and northeastern Brazil are also apparently suitable for the two species, without broad coincidence with human cases. Modeling of niches and distributions of rodent reservoirs indicates potential for transmission of hantavirus across virtually all of Brazil outside the Amazon Basin. PMID:24391989

  3. Angiostrongylus cantonensis and Rat Lungworm Disease in Brazil

    PubMed Central

    de Oliveira Simões, Raquel; Fernandez, Monica Ammon; Júnior, Arnaldo Maldonado

    2013-01-01

    The metastrongyloid nematode genus Angiostrongylus includes 18 species, two of which are relevant from a medical standpoint, Angiostrongylus costaricensis and Angiostrongylus cantonensis. The first was described from Costa Rica in 1971 and causes abdominal angiostrongyliasis in the Americas, including in Brazil. Angiostrongylus cantonensis, first described in 1935 from Canton, China, is the causative agent of eosinophilic meningitis. The natural definitive hosts are rodents, and molluscs are the intermediate hosts. Paratenic or carrier hosts include crabs, freshwater shrimp, amphibians, flatworms, and fish. Humans become infected accidentally by ingestion of intermediate or paratenic hosts and the parasite does not complete the life cycle as it does in rats. Worms in the brain cause eosinophilic meningitis. This zoonosis, widespread in Southeast Asia and the Pacific islands, has now been reported from other regions. In the Americas there are records from the United States, Cuba, Jamaica, Brazil, Ecuador, and Haiti. In Brazil seven human cases have been reported since 2007 from the southeastern and northeastern regions. Epidemiological studies found infected specimens of Rattus norvegicus and Rattus rattus as well as many species of molluscs, including the giant African land snail, Achatina fulica, from various regions of Brazil. The spread of angiostrongyliasis is currently a matter of concern in Brazil. PMID:23901376

  4. Dynamic processes in the mountain catchment

    NASA Astrophysics Data System (ADS)

    Trifonova, Tatiana; Arakelian, Sergei

    2015-04-01

    The process of the river cftchment foundation and the mechanisms being in the basis of its development are not clear at present. Principal phenomena determining the dynamics of formation of the river catchment are under our study in this paper for the case of the mountain basin as an example. The methodology of this monitoring includes the space image recognition and computer data processing of the images for the Maliy Caucasus Mountains. Mountain river catchment formation on the slope of the ridge can be considered as a self-organizing staged process of its evolution passing through several non-equilibrium but steady-state conditions. We consider a system of tributaries in the mountain river catchment as a system of cracks, which are formed on the slope of the mountain massif. In other words, the formation of river networks should be the result of development of several processes, among of which the mechanisms of crack development should play a dominant role. The principal results, discussed in the present report, can be formulated as follow. (1) The mountain catchment (litho-watershed) formation takes place under conditions of the confined states of a mountain massif: on the one hand it is bounded by the surface of the slope; but on the other hand, - by a primary cracks density occurrence (as a spatial distribution 3D-crack net). (2) The development in time of the river catchment takes place by several stages. Each stage specifies a definite energetic state of the system in the mountain massif. (3) The overhead river streams arise not only due to surface water, but and namely due to rising of water from underground water horizons over the watercourse cracks penetrating deeply into the underground. (4) The 3D-river catchment structure results in concept in behavior of the unit as an open nonlinear dynamic system with a spatially distributed feedback. The energetic (endogen) processes of formation, rising and bifurcation for cracks are the consequence of relaxation

  5. Two new species of Dicranocentrus Schött, 1893 (Collembola:Entomobryidae) from Serra do Gandarela, Minas Gerais State, Brazil.

    PubMed

    Xisto, Thiago; Mendonça, Maria Cleide De

    2016-01-01

    Two new species of Dicranocentrus from Southeastern Brazil are described: D. melinus sp. nov. and D. cuprum sp. nov., both from "Parque Nacional da Serra do Gandarela" (Minas Gerais State), Brazil. These species can be included to gracilis-group due to the absence of chaeta A1, S2, Ps and up to 6+6 chaetae P on dorsal head. A male genital plate is for the first time illustrated for the genus. PMID:27396001

  6. Groundwater recharge from point to catchment scale

    NASA Astrophysics Data System (ADS)

    Leterme, Bertrand; Di Ciacca, Antoine; Laloy, Eric; Jacques, Diederik

    2016-04-01

    Accurate estimation of groundwater recharge is a challenging task as only a few devices (if any) can measure it directly. In this study, we discuss how groundwater recharge can be calculated at different temporal and spatial scales in the Kleine Nete catchment (Belgium). A small monitoring network is being installed, that is aimed to monitor the changes in dominant processes and to address data availability as one goes from the point to the catchment scale. At the point scale, groundwater recharge is estimated using inversion of soil moisture and/or water potential data and stable isotope concentrations (Koeniger et al. 2015). At the plot scale, it is proposed to monitor the discharge of a small drainage ditch in order to calculate the field groundwater recharge. Electrical conductivity measurements are necessary to separate shallow from deeper groundwater contribution to the ditch discharge (see Di Ciacca et al. poster in session HS8.3.4). At this scale, two or three-dimensional process-based vadose zone models will be used to model subsurface flow. At the catchment scale though, using a mechanistic, process-based model to estimate groundwater recharge is debatable (because of, e.g., the presence of numerous drainage ditches, mixed land use pixels, etc.). We therefore investigate to which extent various types of surrogate models can be used to make the necessary upscaling from the plot scale to the scale of the whole Kleine Nete catchment. Ref. Koeniger P, Gaj M, Beyer M, Himmelsbach T (2015) Review on soil water isotope based groundwater recharge estimations. Hydrological Processes, DOI: 10.1002/hyp.10775

  7. Creating a catchment perspective for river restoration

    NASA Astrophysics Data System (ADS)

    Benda, L.; Miller, D.; Barquín, J.

    2011-03-01

    One of the major challenges in river restoration is to identify the natural fluvial landscape in catchments with a long history of river control. Intensive land use on valley floors often predates the earliest remote sensing: levees, dikes, dams, and other structures alter valley-floor morphology, river channels and flow regimes. Consequently, morphological patterns indicative of the fluvial landscape including multiple channels, extensive floodplains, wetlands, and fluvial-riparian and tributary-confluence dynamics can be obscured, and information to develop appropriate and cost effective river restoration strategies can be unavailable. This is the case in the Pas River catchment in northern Spain (650 km2), in which land use and development have obscured the natural fluvial landscape in many parts of the basin. To address this issue we coupled general principles of hydro-geomorphic processes with computer tools to characterize the fluvial landscape. Using a 5-m digital elevation model, valley-floor surfaces were mapped according to elevation above the channel and proximity to key geomorphic processes. The predicted fluvial landscape is patchily distributed according to topography, valley morphology, river network structure, and fan and terrace landforms. The vast majority of the fluvial landscape in the main segments of the Pas River catchment is presently masked by human infrastructure, with only 15% not impacted by river control structures and development. The reconstructed fluvial landscape provides a catchment scale context to support restoration planning, in which areas of potential ecological productivity and diversity could be targeted for in-channel, floodplain and riparian restoration projects.

  8. Protodrilus (Protodrilidae, Annelida) from the southern and southeastern Brazilian coasts

    NASA Astrophysics Data System (ADS)

    Di Domenico, Maikon; Martínez, Alejandro; Lana, Paulo da Cunha; Worsaae, Katrine

    2013-12-01

    Protodrilus corderoi, Protodrilus ovarium n. sp. and Protodrilus pythonius n. sp. are reported from beaches in southern and southeastern Brazil and described combining live observations with light and electron scanning microscopy studies. Protodrilus corderoi is redescribed from new collections at the type locality, and a neotype for the species is assigned since the original type material no longer exists. New information on reproductive organs, segmental adhesive glands and unpigmented ciliary receptors as well as morphometrics is provided. Protodrilus ovarium n. sp. and P. pythonius n. sp. are formally described. Protodrilus ovarium n. sp. is diagnosed by the presence of separated lateral organs on segments 7-12, three spermioducts of segments 10-12 and salivary glands in segments 1-9. Protodrilus pythonius n. sp. is defined by the presence of separated lateral organs on segments 7-16, long pygidial lobes and body tapering toward the pygidium. The distribution of the different species in more or less spacious habitats seems to be correlated with their gross morphology. Protodrilus pythonius n. sp., with relatively long and wide body and long palps with ciliary bands, was collected in very coarse sandy sediments at a reflective sheltered beach. Conversely, P. corderoi and P. ovarium n. sp., both possessing more slender bodies with shorter, less ciliated palps, occurred in medium-coarse, well-sorted sediments in the more energetic swash zone of exposed intermediate-reflective beaches. The finding of P. pythonius and P. corderoi in nearby beaches corroborates other studies showing a higher morphological variability among species in different habitats within the same geographical area than among species in the same habitat in different geographical areas.

  9. Similarity and scale in catchment storm response

    NASA Technical Reports Server (NTRS)

    Wood, Eric F.; Sivapalan, Murugesu; Beven, Keith

    1993-01-01

    Until recently, very little progress had been made in understanding the relationship between small-scale variability of topography, soil, and rainfalls and the storm response seen at the catchment scale. The work reviewed here represents the first attempt at a systematic theoretical framework for such understanding in the context of surface runoff generation by different processes. The parameterization of hydrological processes over a range of scales is examined, and the concept of the 'representative elementary area' (REA) is introduced. The REA is a fundamental scale for catchment modeling at which continuum assumptions can be applied for the spatially variable controls and parameters, and spatial patterns no longer have to be considered explicitly. The investigation of scale leads into the concept of hydrologic similarity in which the effects of the environmental controls on runoff generation and flood frequency response be investigated independently of catchment scale. The paper reviews the authors' initial results and hopefully will motivate others to also investigate the issues of hydrologic scale and similarity.

  10. Modeling of facade leaching in urban catchments

    NASA Astrophysics Data System (ADS)

    Coutu, S.; Del Giudice, D.; Rossi, L.; Barry, D. A.

    2012-12-01

    Building facades are protected from microbial attack by incorporation of biocides within them. Flow over facades leaches these biocides and transports them to the urban environment. A parsimonious water quantity/quality model applicable for engineered urban watersheds was developed to compute biocide release from facades and their transport at the urban basin scale. The model couples two lumped submodels applicable at the basin scale, and a local model of biocide leaching at the facade scale. For the facade leaching, an existing model applicable at the individual wall scale was utilized. The two lumped models describe urban hydrodynamics and leachate transport. The integrated model allows prediction of biocide concentrations in urban rivers. It was applied to a 15 km2urban hydrosystem in western Switzerland, the Vuachère river basin, to study three facade biocides (terbutryn, carbendazim, diuron). The water quality simulated by the model matched well most of the pollutographs at the outlet of the Vuachère watershed. The model was then used to estimate possible ecotoxicological impacts of facade leachates. To this end, exceedance probabilities and cumulative pollutant loads from the catchment were estimated. Results showed that the considered biocides rarely exceeded the relevant predicted no-effect concentrations for the riverine system. Despite the heterogeneities and complexity of (engineered) urban catchments, the model application demonstrated that a computationally "light" model can be employed to simulate the hydrograph and pollutograph response within them. It thus allows catchment-scale assessment of the potential ecotoxicological impact of biocides on receiving waters.

  11. Climate change influence on catchment sediment yield

    NASA Astrophysics Data System (ADS)

    Rulli, Maria Cristina; Grossi, Giovanna

    2010-05-01

    The effects of a change in climate are expected to be recognizable in many environmental aspects even at small spatial scales: atmospheric carbon dioxide concentration, air temperature, precipitation pattern (days of snowfall translate in days of rainfall), rainfall intensity and erosivity. As a consequence, strong modifications may affect the rate of evapo-transpiration, infiltration and plant biomass production, but also of the soil erosion. To which extent climate change may affect runoff production, soil erosion and sediment transport in upland catchments is investigated here by combining data of long term precipitation, sediment yield and future climate change provided by Global Circulation Models (GCMs) with a spatially distributed modeling approach to flow generation and surface erosion. The model accounts for changes in the structure and properties of soil and vegetation cover by combining the tube-flux approach to the topographic watershed partitioning through a parsimonious parametrization of the main hydrological processes. This model is used to predict hydrological and sediment fluxes for three small catchments in Saint Gabriel mountains of Southern California under control and climate change conditions. Simulation runs using a 45 years long record of hourly precipitation, both observed and referred to a future scenario, show that climate change may induce a significant modification in the catchment response to storms, with major effects on erosion and flood flows.

  12. Water quality in sugar catchments of Queensland.

    PubMed

    Rayment, G E

    2003-01-01

    Water quality condition and trend are important indicators of the impact of land use on the environment, as degraded water quality causes unwelcome changes to ecosystem composition and health. These concerns extend to the sea, where discharges of nutrients, sediments and toxicants above natural levels are unwelcome, particularly when they drain to the Great Barrier Reef World Heritage Area and other coastal waters of Queensland. Sugarcane is grown in 26 major river catchments in Queensland, most in environmentally sensitive areas. This puts pressure on the Queensland Sugar Industry to manage the land in ways that have minimum adverse off-site impacts. Sugar researchers including CRC Sugar have been associated with water quality studies in North Queensland. These include investigations and reviews to assess the role of groundwater as a pathway for nitrate loss from canelands in the Herbert Catchment, to find causes of oxygen depletion in water (including irrigation runoff) from Ingham to Mackay, to use residues of superseded pesticides as indicators of sediment loss to the sea, and to assemble information on water quality pressure and status in sugar catchments. Key findings, plus information on input pressures are described in this paper, and areas of concern and opportunities discussed. PMID:14653632

  13. VIEW OF SOUTHEASTERN INTERIOR SPACE, FACING NORTHWEST. Douglas Aircraft ...

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

    VIEW OF SOUTHEASTERN INTERIOR SPACE, FACING NORTHWEST. - Douglas Aircraft Company Long Beach Plant, Aircraft Parts Shipping & Receiving Building, 3855 Lakewood Boulevard, Long Beach, Los Angeles County, CA

  14. Four new species of Moneuptychia (Lepidoptera: Satyrinae: Euptychiina) from Brazil.

    PubMed

    Freitas, André V L; Barbosa, Eduardo P; Siewert, Ricardo R; Mielke, Olaf H H; Zacca, Thamara; Azeredo-Espin, Ana Maria L

    2015-01-01

    This paper describes four new species of Moneuptychia as follows: M. montana Freitas, M. vitellina Freitas & Barbosa, M. pervagata Freitas, Siewert & Mielke and M. wahlbergi Freitas, Barbosa, Siewert & Mielke from south and southeastern Brazil. Details are presented on the morphology of adults of all species, and immature stages for two species, and we discuss the taxonomy and identification of the genus Moneuptychia. The mitochondrial CoxI "barcode" region was used for exploring the utility of this DNA marker to identify these species, giving strong support for all new species. PMID:26250011

  15. Manaus, Brazil

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The junctions of the Amazon and the Rio Negro Rivers at Manaus, Brazil. The Rio Negro flows 2300 km from Columbia, and is the dark current forming the north side of the river. It gets its color from the high tannin content in the water. The Amazon is sediment laden, appearing brown in this simulated natural color image. Manaus is the capital of Amazonas state, and has a population in excess of one million. The ASTER image covers an area of 60 x 45 km. This image was acquired on July 16, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation

  16. Spatial dynamics of understorey insectivorous birds and arthropods in a southeastern Brazilian Atlantic woodlot.

    PubMed

    Manhães, M A; Dias, M M

    2011-02-01

    Spatial distribution and spatial relationships in capture rates of understorey insectivorous birds and density of arthropods were investigated in a patch of upper montane rain forest in Minas Gerais state, southeastern Brazil, from January to December 2004. The composition of the arthropod fauna collected was similar to that reported for other tropical forests, with predominance of Araneae, Coleoptera, Hymenoptera and Hemiptera non-Heteroptera. A total of 26 bird species were captured, among which the more common were Dysithamnus mentalis, Conopophaga lineata, Platyrinchus mystaceus, Basileuterus culicivorus and Sclerurus scansor. Variation in the bird capture rates among sampling net lines were not correlated with arthropod density. Rather, individual analyses of some bird species suggest that spatial distribution of understorey insectivorous birds is better explained by habitat type. PMID:21437393

  17. Leaching of nitrogen from forested catchments in Finland

    NASA Astrophysics Data System (ADS)

    Kortelainen, Pirkko; Saukkonen, Sari; Mattsson, Tuija

    1997-12-01

    This study provides an assessment on the spatial variability of the long-term leaching (8-23 years) of nitrogen and organic carbon from 22 forested catchments (0.69-56 km2). The catchments are located throughout Finland excluding the northernmost regions. The Kruunuoja catchment is located in a national park; the other catchments represent typical Finnish forestry land. The leaching from the 21 forestry land catchments can be considered to represent average leaching from Finnish forestry land since the most important forestry practices (ditching, clear-cutting, scarification, and fertilization) since the 1960s have affected about 2.4% of the catchment area per year (compare 2.5% in the entire country in 1980 and 2% in 1991). Moreover, the mean annual runoff from the catchments, 230-420 mm yr-1, agree with the mean annual runoff from Finland (301 mm yr-1 from 1931 to 1990). The major part of the nitrogen transported from the catchments consisted of organic nitrogen (on average 79%). The average inorganic nitrogen proportion ((NO3-N + NH4-N)/Ntot) was lowest (7.3%) in the Kruunuoja catchment and was highest (54%) in the southernmost Teeressuonoja catchment located in the highest anthropogenic nitrogen deposition area. The median C/N ratio in the study streams was high, ranging from 34 to 66. Nitrate leaching from the catchments varied between 2.8 (Kruunuoja) and 100 kg km-2 yr-1 (Teeressuonoja) and was negatively related to C/N ratio in stream water and latitude. The stepwise multiple regression model selected C/N ratio and nitrogen deposition which together explained 72% of the variation in NO3-N leaching. Retention of NO3-N deposition (calculated as ((input-output)/input) was high in all catchments, ranging from 0.99 in Kruunuoja to 0.67 in Teeressuonoja.

  18. Incorporating flood event analyses and catchment structures into model development

    NASA Astrophysics Data System (ADS)

    Oppel, Henning; Schumann, Andreas

    2016-04-01

    The space-time variability in catchment response results from several hydrological processes which differ in their relevance in an event-specific way. An approach to characterise this variance consists in comparisons between flood events in a catchment and between flood responses of several sub-basins in such an event. In analytical frameworks the impact of space and time variability of rainfall on runoff generation due to rainfall excess can be characterised. Moreover the effect of hillslope and channel network routing on runoff timing can be specified. Hence, a modelling approach is needed to specify the runoff generation and formation. Knowing the space-time variability of rainfall and the (spatial averaged) response of a catchment it seems worthwhile to develop new models based on event and catchment analyses. The consideration of spatial order and the distribution of catchment characteristics in their spatial variability and interaction with the space-time variability of rainfall provides additional knowledge about hydrological processes at the basin scale. For this purpose a new procedure to characterise the spatial heterogeneity of catchments characteristics in their succession along the flow distance (differentiated between river network and hillslopes) was developed. It was applied to study of flood responses at a set of nested catchments in a river basin in eastern Germany. In this study the highest observed rainfall-runoff events were analysed, beginning at the catchment outlet and moving upstream. With regard to the spatial heterogeneities of catchment characteristics, sub-basins were separated by new algorithms to attribute runoff-generation, hillslope and river network processes. With this procedure the cumulative runoff response at the outlet can be decomposed and individual runoff features can be assigned to individual aspects of the catchment. Through comparative analysis between the sub-catchments and the assigned effects on runoff dynamics new

  19. Climate change impacts on the seasonality and generation processes of floods - projections and uncertainties for catchments with mixed snowmelt/rainfall regimes

    NASA Astrophysics Data System (ADS)

    Vormoor, K.; Lawrence, D.; Heistermann, M.; Bronstert, A.

    2015-02-01

    Climate change is likely to impact the seasonality and generation processes of floods in the Nordic countries, which has direct implications for flood risk assessment, design flood estimation, and hydropower production management. Using a multi-model/multi-parameter approach to simulate daily discharge for a reference (1961-1990) and a future (2071-2099) period, we analysed the projected changes in flood seasonality and generation processes in six catchments with mixed snowmelt/rainfall regimes under the current climate in Norway. The multi-model/multi-parameter ensemble consists of (i) eight combinations of global and regional climate models, (ii) two methods for adjusting the climate model output to the catchment scale, and (iii) one conceptual hydrological model with 25 calibrated parameter sets. Results indicate that autumn/winter events become more frequent in all catchments considered, which leads to an intensification of the current autumn/winter flood regime for the coastal catchments, a reduction of the dominance of spring/summer flood regimes in a high-mountain catchment, and a possible systematic shift in the current flood regimes from spring/summer to autumn/winter in the two catchments located in northern and south-eastern Norway. The changes in flood regimes result from increasing event magnitudes or frequencies, or a combination of both during autumn and winter. Changes towards more dominant autumn/winter events correspond to an increasing relevance of rainfall as a flood generating process (FGP) which is most pronounced in those catchments with the largest shifts in flood seasonality. Here, rainfall replaces snowmelt as the dominant FGP primarily due to increasing temperature. We further analysed the ensemble components in contributing to overall uncertainty in the projected changes and found that the climate projections and the methods for downscaling or bias correction tend to be the largest contributors. The relative role of hydrological

  20. Effectiveness of Mosquito Magnet® trap in rural areas in the southeastern tropical Atlantic Forest

    PubMed Central

    Sant'Ana, Denise Cristina; de Sá, Ivy Luizi Rodrigues; Sallum, Maria Anice Mureb

    2014-01-01

    Traps are widely employed for sampling and monitoring mosquito populations for surveillance, ecological and fauna studies. Considering the importance of assessing other technologies for sampling mosquitoes, we addressed the effectiveness of Mosquito Magnet® Independence (MMI) in comparison with those of the CDC trap with CO2 and Lurex3® (CDC-A) and the CDC light trap (CDC-LT). Field collections were performed in a rural area within the Atlantic Forest biome, southeastern state of São Paulo, Brazil. The MMI sampled 53.84% of the total number of mosquitoes, the CDC-A (26.43%) and CDC-LT (19.73%). Results of the Pearson chi-squared test (χ2) showed a positive association between CDC-LT and species of Culicini and Uranotaeniini tribes. Additionally, our results suggested a positive association between CDC-A and representatives of the Culicini and Aedini tribes, whereas the MMI was positively associated with the Mansoniini and Sabethini as well as with Anophelinae species. The MMI sampled a greater proportion (78.27%) of individuals of Anopheles than either the CDC-LT (0.82%) or the CDC-A traps (20.91%). Results of the present study showed that MMI performed better than CDC-LT or CDC-A in sampling mosquitoes in large numbers, medically important species and assessing diversity parameters in rural southeastern Atlantic Forest. PMID:25424445

  1. Exploring links between tectonics, catchment morphology and hydrographs across Europe

    NASA Astrophysics Data System (ADS)

    Vanmaercke, Matthias; Campforts, Benjamin; Van Ruyskensvelde, Glenn; Poesen, Jean

    2016-04-01

    A growing number of studies show that contemporary catchment sediment yields (SY, [t/km²/y]) are strongly correlated to patterns of seismic activity at regional to continental scales. Nonetheless, the mechanisms explaining these correlations are still poorly understood. Seismicity may increase SY by triggering landslides or weakening the surface lithology. On the other hand seismicity can be considered as a proxy for tectonic movements, while there is a growing consensus that tectonics exert an important influence on catchment morphology. This morphology influences the properties of runoff events (e.g. peak discharge, stream power). Given the large influence of large runoff events on annual SY, it is therefore possible that observed correlations between SY and seismicity are (at least partly) attributable to tectonic influences on catchment morphology. We test this hypothesis by investigating links between runoff hydrographs and patterns in catchment properties at a European scale using numerous catchment indices such as the slope, channel steepness, circularity, drainage length, river network topology, etc. From DEMs with a resolution of ca. 100m we randomly delineated over 5000 catchments across Europe with an area of 90 to 100 km². For each of these catchments, we simulated a runoff hydrograph, using a simple Hortonian runoff model that routes water through the catchment based on previously proposed flow velocity equations. We made abstraction of rainfall patterns, lithology, land use and all factors other than topography. Hence, the hydrographs only reflect the influence of the morphological properties of the catchments and allow for comparisons. First results show that, apart from average catchment slope, there are very few regional patterns in catchment morphological properties that may significantly affect hydrographs. In some tectonically active regions, channel slopes are slightly steeper compared to catchments with the same average catchment slope in

  2. Imaging crustal structure variation across southeastern Australia

    NASA Astrophysics Data System (ADS)

    Fontaine, Fabrice R.; Tkalčić, Hrvoje; Kennett, Brian L. N.

    2013-01-01

    A broad-band seismic network of 28 three-component seismometers was deployed in southeastern Australia to examine variations in crustal thickness across the transition between Precambrian and Phanerozoic lithosphere. Receiver function observations and modelling of P-to-S conversions at the Mohorovičić discontinuity (Moho) have been employed to investigate: (i) the variations in the Moho depth across southeastern Australia, and (ii) the nature of the transition between crust and mantle. Data from temporary deployments were used together with data from the few permanent broad-band stations in the region. The extraction of P-receiver functions from high-quality seismic data recorded on these stations has enabled the determination of the crustal thickness across the region. The crustal thicknesses lie in the range 28-48 km. The Moho depth is generally well correlated with the Earth surface elevation in the southeastern Australia. The Moho estimates from receiver functions are in good agreement with results from reflection profiling. The average crustal thickness is found to be around 39 km beneath the Precambrian area in the west and even thicker beneath the Lachlan Orogen in the east (~ 43 km). The average crustal thickness in between, beneath the Murray Basin is thinner ~ 32 km. Interestingly, the crust in the Mount Gambier volcanic area is rather thick ~ 41 km, suggesting that the limit between the Delamerian and western Lachlan orogens is located east of Mount Gambier. Our results favour a position for the Tasman Line generally consistent with the interpretation by Direen and Crawford (2003) and thus to the east of the location favoured by many authors. The broader crust-mantle transition and thicker crust beneath the Lachlan Orogen suggest the presence of magmatic underplating at the base of the lower crust. The intermediate nature of the crust-mantle transition also suggests magmatic underplating beneath the Gawler Craton and the Curnamona Province.

  3. Land-use change in the Atlantic rainforest region: Consequences for the hydrology of small catchments

    NASA Astrophysics Data System (ADS)

    Salemi, Luiz Felippe; Groppo, Juliano Daniel; Trevisan, Rodrigo; de Moraes, Jorge Marcos; de Barros Ferraz, Silvio Frosini; Villani, João Paulo; Duarte-Neto, Paulo José; Martinelli, Luiz Antonio

    2013-08-01

    The Atlantic forest of Brazil is one of the most endangered ecosystems in the world. Despite approximately 500 years of intense land-use change in this biome, the influence of land-use changes on hydrological processes have yet to be investigated in-depth. To bridge this gap, we studied various features of three small catchments covered by pristine original montane cloud forest, pasture, and eucalyptus for 2 years (January 2008-December 2009), including the hydraulic properties of soils, throughfall, overland flow and streamflow processes. The forest saturated hydraulic conductivity (Ksat) was higher near the soil surface (0.15 m depth) compared to eucalyptus and pasture. As a consequence, higher overland flow generation in terms of volume was observed in pasture and eucalyptus. Despite this increase in overland flow generation, overland flow coefficients (overland flow: precipitation ratio) were substantially low throughout the study period with slightly higher values in 2009. These low overland flow coefficients were attributed to the large predominance of low rainfall intensities (<10 mm h-1) as well as high Ksat spatial variability. These overland flow results and the absence of perched water table showed that catchments seem still to be dominated by vertical flowpaths irrespective of land-use. In this sense, the annual streamflow is still dominated by baseflow in all of the catchments. Therefore, despite reductions regarding interception and saturated hydraulic conductivity when converting forest to eucalyptus and pasture, the prevailing rainfall intensities do not cause runoff generation processes to be substantially different among land-uses. Forest and eucalyptus convert a similar proportion of annual precipitation to annual streamflow, with the more likely factors for these results being the high interception under forest and high transpiration under eucalyptus. Finally, cloud forest conversion to pasture does not promote significant monthly streamflow

  4. A 500-year history of floods in the semi arid basins of south-eastern Spain

    NASA Astrophysics Data System (ADS)

    Sánchez García, Carlos; Schulte, Lothar; Peña, Juan Carlos; Carvalho, Filpe; Brembilla, Carla

    2016-04-01

    Floods are one of the natural hazards with higher incidence in the south-eastern Spain, the driest region in Europe, causing fatalities, damage of infrastructure and economic losses. Flash-floods in semi arid environments are related to intensive rainfall which can last from few hours to days. These floods are violent and destructive because of their high discharges, sediment transport and aggradation processes in the flood plain. Also during historical times floods affected the population in the south-eastern Spain causing sever damage or in some cases the complete destruction of towns. Our studies focus on the flood reconstruction from historical sources of the Almanzora, Aguas and Antas river basins, which have a surface between 260-2600 km2. We have also compiled information from the Andarax river and compared the flood series with the Guadalentín and Segura basins from previous studies (Benito et. al., 2010 y Machado et al., 2011). Flood intensities have been classified in four levels according to the type of damage: 1) ordinary floods that only affect agriculture plots; 2) extraordinary floods which produce some damage to buildings and hydraulic infrastructure; 3) catastrophic floods which caused sever damage, fatalities and partial or complete destruction of towns. A higher damage intensity of +1 magnitude was assigned when the event is recorded from more than one major sub-basin (stretches and tributaries such as Huércal-Overa basin) or catchment (e.g. Antas River). In total 102 incidences of damages and 89 floods were reconstructed in the Almanzora (2.611 km2), Aguas (539 km2), Antas (261 km2) and Andarax (2.100 km2) catchments. The Almanzora River was affected by 36 floods (1550-2012). The highest events for the Almanzora River were in 1580, 1879, 1973 and 2012 producing many fatalities and destruction of several towns. In addition, we identified four flood-clusters 1750-1780, 1870-1900, 1960-1977 and 1989-2012 which coincides with the periods of

  5. Trophic Relationships and Habitat Preferences of Delphinids from the Southeastern Brazilian Coast Determined by Carbon and Nitrogen Stable Isotope Composition

    PubMed Central

    Bisi, Tatiana Lemos; Dorneles, Paulo Renato; Lailson-Brito, José; Lepoint, Gilles; Azevedo, Alexandre de Freitas; Flach, Leonardo; Malm, Olaf; Das, Krishna

    2013-01-01

    To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ13C) and nitrogen (δ15N) isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ13C and δ15N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ13C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ13C value, while oceanic species showed significantly lower δ13C values. The highest δ15N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ15N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ13C values, but similar δ15N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ13C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area. PMID:24358155

  6. The occurrence of amphibians in bromeliads from a southeastern Brazilian restinga habitat, with special reference to Aparasphenodon brunoi (Anura, Hylidae).

    PubMed

    Teixeira, R L; Schineider, J A P; Almeida, G I

    2002-05-01

    Five species of anuran amphibians, all belonging to the family Hylidae, were collected at Praia das Neves, municipality of President Kennedy, southeastern Brazil. The species were represented by four genera: Scinax, Hyla, Aparasphenodon, and Trachycephalus. Four species (A. brunoi, Hyla albomarginata, Scinax altera, and S. cuspidatus) were found during the dry season (August 1999), and two (A. brunoi and Trachycephalus nigromaculatus) in the rainy season (February 2000). Aparasphenodon brunoi was the most abundant species in Praia das Neves. Some reproductive aspects and feeding habits of this hylid were investigated. Aparasphenodon brunoi was found mainly inside the bromeliad Aechmea lingulata, the largest plant analyzed. Fifteen specimens were collected during the dry season (August 1999) (11 males and 4 females). During the rainy season (February 2000), we collected 14 specimens (3 males, 10 females, and 1 juvenile). Sex-ratio was 1:1. Frogs ranged in snout-vent length from 31.2 to 69.3 mm. Females were larger than males. One female had 1,451 fully developed oocytes in her ovaries. The major groups of prey found in the stomachs were: Insecta, Myriapoda, and Arachnida. Blattodea, Orthoptera, Lepidoptera, and Hymenoptera (only ants) were the main food types in frequency, number, and weight. Aparasphenodon brunoi is a threatened species in many habitats of southeastern Brazil. Only natural vegetation protection may guarantee its survival during the immediate future. PMID:12489399

  7. Trophic relationships and habitat preferences of delphinids from the southeastern Brazilian coast determined by carbon and nitrogen stable isotope composition.

    PubMed

    Bisi, Tatiana Lemos; Dorneles, Paulo Renato; Lailson-Brito, José; Lepoint, Gilles; Azevedo, Alexandre de Freitas; Flach, Leonardo; Malm, Olaf; Das, Krishna

    2013-01-01

    To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ(13)C) and nitrogen (δ(15)N) isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ(13)C and δ(15)N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ(13)C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ(13)C value, while oceanic species showed significantly lower δ(13)C values. The highest δ(15)N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ(15)N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ(13)C values, but similar δ(15)N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ(13)C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area. PMID:24358155

  8. A Hybrid Statistical-Physical Regression Approach for Flood Depth Estimation in Southeastern Europe

    NASA Astrophysics Data System (ADS)

    Galasso, C.; Senarath, S. U.; Duggan, D. P.

    2012-12-01

    catchments in Southeastern Europe. The regression relationships are developed by using the output from a numerical inland flood model developed for Germany.

  9. 76 FR 60015 - Southeastern Power Administration; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southeastern Power Administration; Notice of Filing Take notice that on September 8, 2011, the Southeastern Power Administration submitted its Rate Order No. SEPA-54...

  10. 76 FR 60015 - Southeastern Power Administration; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southeastern Power Administration; Notice of Filing Take notice that on September 14, 2011, the Southeastern Power Administration submitted its Rate Order No. SEPA-55...

  11. 27 CFR 9.72 - Southeastern New England.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Southeastern New England. 9.72 Section 9.72 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.72 Southeastern New England. (a) Name. The...

  12. 75 FR 67960 - Southeastern Power Administration; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southeastern Power Administration; Notice of Filing October 28, 2010. Take notice that on October 6, 2010, the Southeastern Power Administration, pursuant to Order No....

  13. 77 FR 56838 - Southeastern Power Administration; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southeastern Power Administration; Notice of Filing Take notice that on September 5, 2012, the Southeastern Power Administration submitted its Rate Order No. SEPA-56...

  14. Snowcover interaction with climate, topography & vegetation in mountain catchments in catchments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mountainous regions in the semi-arid Western US are snow-dominated with little or no summer precipitation. Wind and topographic structure control snow deposition, causing tremendous spatial heterogeneity in the distribution of the snowcover and the delivery of melt water across mountain catchments....

  15. Modeling relationships between catchment attributes and river water quality in southern catchments of the Caspian Sea.

    PubMed

    Hasani Sangani, Mohammad; Jabbarian Amiri, Bahman; Alizadeh Shabani, Afshin; Sakieh, Yousef; Ashrafi, Sohrab

    2015-04-01

    Increasing land utilization through diverse forms of human activities, such as agriculture, forestry, urban growth, and industrial development, has led to negative impacts on the water quality of rivers. To find out how catchment attributes, such as land use, hydrologic soil groups, and lithology, can affect water quality variables (Ca(2+), Mg(2+), Na(+), Cl(-), HCO 3 (-) , pH, TDS, EC, SAR), a spatio-statistical approach was applied to 23 catchments in southern basins of the Caspian Sea. All input data layers (digital maps of land use, soil, and lithology) were prepared using geographic information system (GIS) and spatial analysis. Relationships between water quality variables and catchment attributes were then examined by Spearman rank correlation tests and multiple linear regression. Stepwise approach-based multiple linear regressions were developed to examine the relationship between catchment attributes and water quality variables. The areas (%) of marl, tuff, or diorite, as well as those of good-quality rangeland and bare land had negative effects on all water quality variables, while those of basalt, forest land cover were found to contribute to improved river water quality. Moreover, lithological variables showed the greatest most potential for predicting the mean concentration values of water quality variables, and noting that measure of EC and TDS have inversely associated with area (%) of urban land use. PMID:25395322

  16. Validation of Pacific Northwest Hydrologic Landscapes at the Catchment Scale

    NASA Astrophysics Data System (ADS)

    Sawicz, K. A.; Leibowitz, S. G.; Comeleo, R. L.; Wigington, P. J., Jr.

    2014-12-01

    The interaction between the physical properties of a catchment (form) and climatic forcing of precipitation and energy control how water is partitioned, stored, and conveyed through a catchment (function). Hydrologic Landscapes (HLs) were previously developed across Oregon and describe climatic and physical properties for over 5000 assessment units. This approach was then extended to the three Pacific Northwest states of Washington, Oregon and Idaho (PNW HL). The HLs were developed using the National Hydrography Dataset's WBD HU12 scale and are comprised of classification components describing climate, climate seasonality, aquifer permeability, terrain, and soil permeability. To compare the PNW HL classification to catchment hydrologic behavior, HLs were aggregated to catchment scale to compare against the input/output of water in the catchment. HL aggregation must preserve information on the location of the HL within the catchment outlet (upstream vs. downstream) and properties of that HL (i.e. water source vs. sink). Catchment function was investigated by use of hydrologic signatures, which are attributes of long-term time series of water into and out of the catchment. Signatures include Runoff Ratio, Baseflow Index, Snow Ratio, and Recession Coefficients. This study has three primary objectives: 1) derivation of hydrologic signatures to capture the hydrologic behavior for catchments in the Pacific Northwest: 2) development of methodology to aggregate HLs to the catchment scale; and 3) statistical analysis of signature values and trends with respect to aggregated HL classification. We hypothesize that we will find: 1) strong relationships between aggregated HLs and hydrologic signatures; 2) signatures related to water balance are explained by climatic conditions; and 3) signatures describing flow paths are predicted by terrain, soil, and aquifer permeability. This study examined 230 catchments to achieve objectives and test hypotheses stated.

  17. Lithogenic and cosmogenic tracers in catchment hydrology

    SciTech Connect

    Nimz, G.J.

    1995-01-01

    A variety of physical processes affect solute concentrations within catchment waters. The isotopic compositions of the solutes can indicate which processes have determined the observed concentrations. These processes together constitute the physical history of the water, which is one of the primary concerns in hydrology. Many groundwater solutes are derived as a result of interaction between the water and the rock and/or soil within the system. These are termed {open_quotes}lithogenic{close_quotes} solutes. The isotopic compositions of these solutes provide information regarding rock-water interactions. Many other solutes have their isotopic compositions determined both internally and externally to the catchment system. Important members of this group include solutes that have isotopic compositions produced by atomic particle interactions with other nuclides. The source of the atomic particles can be cosmic radiation (producing {open_quotes}cosmogenic{close_quotes} nuclides in the atmosphere and land surface), anthropogenic nuclear reactions (producing {open_quotes}thermonuclear{close_quotes} nuclides), or radioactive and fission decay of naturally-occurring elements, such as U and Th (producing {open_quotes}in-situ{close_quotes} lithogenic nuclides in the deep subsurface). Current language usage often combines all of the atomic particle-produced nuclides under the heading {open_quotes}cosmogenic nuclides{close_quotes}, and for simplicity we will often follow that usage, although always clearly indicating which variety is being discussed. This paper addresses the processes that affect the lithogenic and cosmogenic solute compositions in groundwater, and how these compositions can therefore be used in integrative ways to understand the physical history of groundwater within a catchment system.

  18. Describing Ecosystem Complexity through Integrated Catchment Modeling

    NASA Astrophysics Data System (ADS)

    Shope, C. L.; Tenhunen, J. D.; Peiffer, S.

    2011-12-01

    Land use and climate change have been implicated in reduced ecosystem services (ie: high quality water yield, biodiversity, and agricultural yield. The prediction of ecosystem services expected under future land use decisions and changing climate conditions has become increasingly important. Complex policy and management decisions require the integration of physical, economic, and social data over several scales to assess effects on water resources and ecology. Field-based meteorology, hydrology, soil physics, plant production, solute and sediment transport, economic, and social behavior data were measured in a South Korean catchment. A variety of models are being used to simulate plot and field scale experiments within the catchment. Results from each of the local-scale models provide identification of sensitive, local-scale parameters which are then used as inputs into a large-scale watershed model. We used the spatially distributed SWAT model to synthesize the experimental field data throughout the catchment. The approach of our study was that the range in local-scale model parameter results can be used to define the sensitivity and uncertainty in the large-scale watershed model. Further, this example shows how research can be structured for scientific results describing complex ecosystems and landscapes where cross-disciplinary linkages benefit the end result. The field-based and modeling framework described is being used to develop scenarios to examine spatial and temporal changes in land use practices and climatic effects on water quantity, water quality, and sediment transport. Development of accurate modeling scenarios requires understanding the social relationship between individual and policy driven land management practices and the value of sustainable resources to all shareholders.

  19. Evaluation of TOPLATS on three Mediterranean catchments

    NASA Astrophysics Data System (ADS)

    Loizu, Javier; Álvarez-Mozos, Jesús; Casalí, Javier; Goñi, Mikel

    2016-08-01

    Physically based hydrological models are complex tools that provide a complete description of the different processes occurring on a catchment. The TOPMODEL-based Land-Atmosphere Transfer Scheme (TOPLATS) simulates water and energy balances at different time steps, in both lumped and distributed modes. In order to gain insight on the behavior of TOPLATS and its applicability in different conditions a detailed evaluation needs to be carried out. This study aimed to develop a complete evaluation of TOPLATS including: (1) a detailed review of previous research works using this model; (2) a sensitivity analysis (SA) of the model with two contrasted methods (Morris and Sobol) of different complexity; (3) a 4-step calibration strategy based on a multi-start Powell optimization algorithm; and (4) an analysis of the influence of simulation time step (hourly vs. daily). The model was applied on three catchments of varying size (La Tejeria, Cidacos and Arga), located in Navarre (Northern Spain), and characterized by different levels of Mediterranean climate influence. Both Morris and Sobol methods showed very similar results that identified Brooks-Corey Pore Size distribution Index (B), Bubbling pressure (ψc) and Hydraulic conductivity decay (f) as the three overall most influential parameters in TOPLATS. After calibration and validation, adequate streamflow simulations were obtained in the two wettest catchments, but the driest (Cidacos) gave poor results in validation, due to the large climatic variability between calibration and validation periods. To overcome this issue, an alternative random and discontinuous method of cal/val period selection was implemented, improving model results.

  20. Equitable water allocation in a heavily committed international catchment area: the case of the Komati Catchment

    NASA Astrophysics Data System (ADS)

    Nkomo, Sakhiwe; van der Zaag, Pieter

    This paper investigates water availability and use in the Komati catchment. The Komati catchment is shared by Swaziland and South Africa and forms part of the Incomati basin, with Mozambique as the third riparian country. In 2002 the three countries reached agreement about how the scarce water should be allocated, based on the principle of equitable and sustainable utilization, as stipulated by the SADC Protocol. The Komati catchment has five main water uses: afforestation, irrigation, the environment, urban/industrial/mining (UIM), and interbasin water transfers (for industrial use). In addition, South Africa and Swaziland have committed themselves to satisfy a certain cross border flow to downstream Mozambique. Frequently, debate has arisen between users and riparian countries on the direction that water resources development has taken in the catchment. Downstream farmers have often complained about interbasin transfers taking place in the upstream portions of the catchment. There has also been animosity about effecting environmental flow releases. A relatively simple, spreadsheet-based water resources model (Waflex) was developed to analyse water availability and use under current and future scenarios. The results were then compared to results obtained from another model that was used in a joint study by Mozambique, South Africa and Swaziland. The Waflex model showed a high degree of consistency with the one used for comparison, especially in terms of trends. It was found that the recent completion of two new dams has improved water supply to irrigation in the two countries. Future water demands will result in appreciable shortages for irrigation and domestic use. The agreed maximum development levels will soon outstrip the ability of the catchment’s supply. The paper shows that a combination of measures will be required to ensure equitable and sustainable water utilisation in the Komati catchment. These will have to be agreed by the riparian countries

  1. [Voronoi s Diagram for defining catchment areas for public hospitals in the Municipality of Rio de Janeiro].

    PubMed

    Rezende, F A; Almeida, R M; Nobre, F F

    2000-01-01

    One of the most important pieces of information for health resources planning is the definition of catchment areas for health units. Voronoi Diagrams are a potential technique for this purpose. They are polygons with the property whereby adjacent polygons have their borders located within the same distance of the respective generator points. One possible adjustment to the catchment areas thus defined is the use of weighted Voronoi Diagrams, which result in an improved representation of a health unit's actual capacity. In this study, the 21 public general hospitals in the city of Rio de Janeiro, Brazil, were used as generator points for Voronoi Diagrams. Non-weighted Voronoi Diagrams were initially implemented and then used as the basis for obtaining weighted Voronoi Diagrams, using as weights the annual admission rates estimated for each unit. In the classic Voronoi Diagram case, some catchment areas had similar sizes, although their respective health units had different characteristics. In the weighted case the areas were modified in a way that appeared closer to the actual functioning of the units. The method appeared simple to implement, used easy-to-access data, and did not rely on geopolitical considerations such as existing administrative areas. It thus provided a more realistic picture of a unit's capacity to support basic health programs. PMID:10883045

  2. Assessing catchment connectivity using hysteretic loops

    NASA Astrophysics Data System (ADS)

    Keesstra, Saskia; Masselink, Rens; Goni, Mikel; Campo, Miguel Angel; Gimenez, Rafael; Casali, Javier; Seeger, Manuel

    2015-04-01

    Sediment connectivity is a concept which can explain the origin, pathways and sinks of sediments within landscapes. This information is valuable for land managers to be able to take appropriate action at the correct place. Hysteresis between sediment and water discharge can give important information about the sources , pathways and conditions of sediment that arrives at the outlet of a catchment. "Hysteresis" happens when the sediment concentration associated with a certain flow rate is different depending on the direction in which the analysis is performed -towards the increase or towards the diminution of the flow. This phenomenon to some extent reflects the way in which the runoff generation processes are conjugated with those of the production and transport of sediments, hence the usefulness of hysteresis as a diagnostic hydrological parameter. However, the complexity of the phenomena and factors which determine hysteresis make its interpretation uncertain or, at the very least, problematic. Many types of hysteretic loops have been described as well as the cause for the shape of the loop, mainly describing the origin of the sediments. In this study, several measures to objectively classify hysteretic loops in an automated way were developed. These were consecutively used to classify several hundreds of loops from several agricultural catchments in Northern Spain. The data set for this study comes from four experimental watersheds in Navarre (Spain), owned and maintained by the Government of Navarre. These experimental watersheds have been monitored and studied since 1996 (La Tejería and Latxaga) and 2001 (Oskotz "principal", Op, and Oskotz "woodland", Ow). La Tejería and Latxaga watersheds, located in the Central Western part of Navarre, are roughly similar to each other regarding size (approximately 200 ha), geology (marls and sandstones), soils (fine texture topsoil), climate (humid sub Mediterranean) and land use (80-90% cultivated with winter grain crops

  3. Zoonotic Leprosy in the Southeastern United States

    PubMed Central

    Sharma, Rahul; Singh, Pushpendra; Loughry, W.J.; Lockhart, J. Mitchell; Inman, W. Barry; Duthie, Malcolm S.; Pena, Maria T.; Marcos, Luis A.; Scollard, David M.; Cole, Stewart T.

    2015-01-01

    Nine-banded armadillos (Dasypus novemcinctus) are naturally infected with Mycobacterium leprae and have been implicated in zoonotic transmission of leprosy. Early studies found this disease mainly in Texas and Louisiana, but armadillos in the southeastern United States appeared to be free of infection. We screened 645 armadillos from 8 locations in the southeastern United States not known to harbor enzootic leprosy for M. leprae DNA and antibodies. We found M. leprae–infected armadillos at each location, and 106 (16.4%) animals had serologic/PCR evidence of infection. Using single-nucleotide polymorphism variable number tandem repeat genotyping/genome sequencing, we detected M. leprae genotype 3I-2-v1 among 35 armadillos. Seven armadillos harbored a newly identified genotype (3I-2-v15). In comparison, 52 human patients from the same region were infected with 31 M. leprae types. However, 42.3% (22/52) of patients were infected with 1 of the 2 M. leprae genotype strains associated with armadillos. The geographic range and complexity of zoonotic leprosy is expanding. PMID:26583204

  4. Zoonotic Leprosy in the Southeastern United States.

    PubMed

    Sharma, Rahul; Singh, Pushpendra; Loughry, W J; Lockhart, J Mitchell; Inman, W Barry; Duthie, Malcolm S; Pena, Maria T; Marcos, Luis A; Scollard, David M; Cole, Stewart T; Truman, Richard W

    2015-12-01

    Nine-banded armadillos (Dasypus novemcinctus) are naturally infected with Mycobacterium leprae and have been implicated in zoonotic transmission of leprosy. Early studies found this disease mainly in Texas and Louisiana, but armadillos in the southeastern United States appeared to be free of infection. We screened 645 armadillos from 8 locations in the southeastern United States not known to harbor enzootic leprosy for M. leprae DNA and antibodies. We found M. leprae-infected armadillos at each location, and 106 (16.4%) animals had serologic/PCR evidence of infection. Using single-nucleotide polymorphism variable number tandem repeat genotyping/genome sequencing, we detected M. leprae genotype 3I-2-v1 among 35 armadillos. Seven armadillos harbored a newly identified genotype (3I-2-v15). In comparison, 52 human patients from the same region were infected with 31 M. leprae types. However, 42.3% (22/52) of patients were infected with 1 of the 2 M. leprae genotype strains associated with armadillos. The geographic range and complexity of zoonotic leprosy is expanding. PMID:26583204

  5. Human-Landscape interaction in cultivated lowland catchments (Louroux catchment, Loire Valley, France)

    NASA Astrophysics Data System (ADS)

    Cerdan, Olivier; Foucher, Anthony; Gay, Aurore; Salvador Blanes, Sébastien; Evrard, Olivier; Desmet, Marc

    2015-04-01

    Change of land use or agricultural practices are known to have high impacts on sediment transfer in catchments and rivers. Numerous studies have particularly illustrated these effects in sloping land in tropical areas undergoing deforestation. Much less attention has been paid to lowland humid areas, where permanent land uses have been plowed more recently. However recent studies reported significant erosion rates in these environments despite the gentle topography and the temperate climate. In order to quantify these changing fluxes of sediment, several instrumentation and historical database analyses were carried out in various catchments of the Loire Valley, France. More particularly, a multiparameter analysis was conducted on sedimentary deposits of a pond created in the 11th century in a catchment representative of cultivated and drained lowland environments where an intensification of agricultural practices has occurred during the last 60 years. The results showed that the initial land consolidation period (1954-1960) was characterized by a dominance of allochtonous material input to the pond. This input represents an erosion of 1900 to 2300 t.km-².yr-1 originating from the catchment. Then, between 1970-1990, terrigenous material flow decreased progressively and tended to stabilize, whereas eutrophication and associated primary production increased in the pond. In addition to these temporal changes, material input across the pond during the last 10 years corresponds to a loss of material in the catchment ranging between 90 and 102 t.km-2.yr-1. While a strong decrease is observed, it still represents a 60-fold increase of the sediment fluxes to the pond compared to the preintensification period. Subsequent research monitoring studies permitted to differentiate between the different sources of sediment and highlight the importance of surface erosion during flood events and of bank erosion during low flows. The increased export of the sediment is primarily due

  6. Media Monopoly in Brazil.

    ERIC Educational Resources Information Center

    Amaral, Roberto; Guimaraes, Cesar

    1994-01-01

    Documents the process of broadcasting media development in Brazil, the failure of new technologies to produce democratization, and the barriers to democratization erected by monopolization and "metastasis." (SR)

  7. Analysis of groundwater flow in mountainous, headwater catchments with permafrost

    NASA Astrophysics Data System (ADS)

    Evans, Sarah G.; Ge, Shemin; Liang, Sihai

    2015-12-01

    Headwater catchments have a direct impact on the water resources of downstream lowland regions as they supply freshwater in the form of surface runoff and discharging groundwater. Often, these mountainous catchments contain expansive permafrost that may alter the natural topographically controlled groundwater flow system. As permafrost could degrade with climate change, it is imperative to understand the effect of permafrost on groundwater flow in headwater catchments. This study characterizes groundwater flow in mountainous headwater catchments and evaluates the effect of permafrost in the context of climate change on groundwater movement using a three-dimensional, finite element, hydrogeologic model. The model is applied to a representative headwater catchment on the Qinghai-Tibet Plateau, China. Results from the model simulations indicate that groundwater contributes significantly to streams in the form of baseflow and the majority of groundwater flow is from the shallow aquifer above the permafrost, disrupting the typical topographically controlled flow pattern observed in most permafrost-free headwater catchments. Under a warming scenario where mean annual surface temperature is increased by 2°C, reducing the areal extent of permafrost in the catchment, groundwater contribution to streamflow may increase three-fold. These findings suggest that, in headwater catchments, permafrost has a large influence on groundwater flow and stream discharge. Increased annual air temperatures may increase groundwater discharge to streams, which has implications for ecosystem health and the long-term availability of water resources to downstream regions.

  8. How does spatial variability of climate affect catchment streamflow predictions?

    NASA Astrophysics Data System (ADS)

    Patil, Sopan D.; Wigington, Parker J.; Leibowitz, Scott G.; Sproles, Eric A.; Comeleo, Randy L.

    2014-09-01

    Spatial variability of climate can negatively affect catchment streamflow predictions if it is not explicitly accounted for in hydrologic models. In this paper, we examine the changes in streamflow predictability when a hydrologic model is run with spatially variable (distributed) meteorological inputs instead of spatially uniform (lumped) meteorological inputs. Both lumped and distributed versions of the EXP-HYDRO model are implemented at 41 meso-scale (500-5000 km2) catchments in the Pacific Northwest region of USA. We use two complementary metrics of long-term spatial climate variability, moisture homogeneity index (IM) and temperature variability index (ITV), to analyze the performance improvement with distributed model. Results show that the distributed model performs better than the lumped model in 38 out of 41 catchments, and noticeably better (>10% improvement) in 13 catchments. Furthermore, spatial variability of moisture distribution alone is insufficient to explain the observed patterns of model performance improvement. For catchments with low moisture homogeneity (IM < 80%), IM is a better predictor of model performance improvement than ITV; whereas for catchments with high moisture homogeneity (IM > 80%), ITV is a better predictor of performance improvement than IM. Based on the results, we conclude that: (1) catchments that have low homogeneity of moisture distribution are the obvious candidates for using spatially distributed meteorological inputs, and (2) catchments with a homogeneous moisture distribution benefit from spatially distributed meteorological inputs if they also have high spatial variability of precipitation phase (rain vs. snow).

  9. Standardised survey method for identifying catchment risks to water quality.

    PubMed

    Baker, D L; Ferguson, C M; Chier, P; Warnecke, M; Watkinson, A

    2016-06-01

    This paper describes the development and application of a systematic methodology to identify and quantify risks in drinking water and recreational catchments. The methodology assesses microbial and chemical contaminants from both diffuse and point sources within a catchment using Escherichia coli, protozoan pathogens and chemicals (including fuel and pesticides) as index contaminants. Hazard source information is gathered by a defined sanitary survey process involving use of a software tool which groups hazards into six types: sewage infrastructure, on-site sewage systems, industrial, stormwater, agriculture and recreational sites. The survey estimates the likelihood of the site affecting catchment water quality, and the potential consequences, enabling the calculation of risk for individual sites. These risks are integrated to calculate a cumulative risk for each sub-catchment and the whole catchment. The cumulative risks process accounts for the proportion of potential input sources surveyed and for transfer of contaminants from upstream to downstream sub-catchments. The output risk matrices show the relative risk sources for each of the index contaminants, highlighting those with the greatest impact on water quality at a sub-catchment and catchment level. Verification of the sanitary survey assessments and prioritisation is achieved by comparison with water quality data and microbial source tracking. PMID:27280603

  10. Range-wide selection of catchments for Pacific salmon conservation.

    PubMed

    Pinsky, Malin L; Springmeyer, Dane B; Goslin, Matthew N; Augerot, Xanthippe

    2009-06-01

    Freshwater ecosystems are declining in quality globally, but a lack of data inhibits identification of areas valuable for conservation across national borders. We developed a biological measure of conservation value for six species of Pacific salmon (Oncorhynchus spp.) in catchments of the northern Pacific across Canada, China, Japan, Russia, and the United States. We based the measure on abundance and life-history richness and a model-based method that filled data gaps. Catchments with high conservation value ranged from California to northern Russia and included catchments in regions that are strongly affected by human development (e.g., Puget Sound). Catchments with high conservation value were less affected by agriculture and dams than other catchments, although only 1% were within biodiversity reserves. Our set of high-value areas was largely insensitive to simulated error, although classification remained uncertain for 3% of catchments. Although salmon face many threats, we propose they will be most likely to exhibit resilience into the future if a complementary mosaic of conservation strategies can be proactively adopted in catchments with healthy salmon populations. Our analysis provides an initial map of where these catchments are likely to be located. PMID:19220368

  11. Metapeachia schlenzae sp. nov. (Cnidaria: Actiniaria: Haloclavidae) a new burrowing sea anemone from Brazil, with a discussion of the genus Metapeachia.

    PubMed

    Gusmão, Luciana C

    2016-01-01

    The diversity of burrowing sea anemones from Brazil is poorly known with only three species recorded. Metapeachia schlenzae sp. nov. is described from specimens collected in the intertidal zone of São Sebastião and Cabo Frio in the southeastern coast of Brazil. Metapeachia schlenzae sp. nov. is the second species described for the genus and the second haloclavid recorded from Brazil. A comparison between Metapeachia schlenzae sp. nov. and Metapeachia tropica, the type species of the genus, is included. The two valid species of Metapeachia differ in the morphology of the conchula, internal anatomy, cnidae and geographical distribution. PMID:27395931

  12. Water Quality-Quantity Evaluation of the Ribeirão das Posses Watershed, Brazil, applying the AgES-W model.

    NASA Astrophysics Data System (ADS)

    Green, T. R.; Cruz, P. P. N. D.; Figueiredo, R. D. O.; Camargo, P. B. D.; Santos, C. P.

    2015-12-01

    Southeastern Brazil is under a period of drought that has impacted the conservation of watersheds and the management of water quality and quantity for agricultural and urban demands. In this context agro-hydrological modeling tools can generate information of water response over time in response to climate and landuse changes. A 12-km2 watershed which has suffered from anthropogenic activities is the Ribeirão das Posses watershed that is located in the extreme south of Minas Gerais State and is a headwater catchment of the Jaguari river, one of the contributing rivers of the Cantareira Reservoir Complex in the state of São Paulo. This watershed had its landscape changed over the last century from native forests to more homogeneous vegetation for pastures and small crops and some forest plantations fragments with eucalyptus. Currently, the Conservative Waters project has planted some small areas with vegetation of native species, especially where there are springs and at the top of the hills, in order to recover degraded areas and improve the hydrogeochemistry in this study basin. In this context, the AgroEcoSystem-Watershed (AgES-W) model is presented to simulate the water movement and storage in agricultural watersheds with different spatial resolutions of land areas or hydrological responses units. The objectives are to evaluate the quality and quantity of water in Ribeirão das Posses Basin using measured data, then simulate these responses in space and time to test the AgES-W model. The period chosen for research was from 2011 to 2015, because the water quality data were collected during this period. The answers that we hope to find out are: How well does the AgES-W model simulate this Brazilian watershed in the tropics? What are the future prospects of the quality and quantity of water in this basin? The results will help to guide hydrological simulations in similar tropical environments in Brazil in this and other agricultural watersheds with AgES-W.

  13. A detailed study on Catchment delineation for Urban areas

    NASA Astrophysics Data System (ADS)

    Sharma, B.; B M, A.; Lohani, B.; Jain, A.

    2015-12-01

    Urban flood modelling is carried out for predicting, analysing and planning of floods in urban areas. Catchment information is an important input for urban flood modelling. Automatic catchment delineation at gully gratings for urban areas using appropriate software packages/methods along with an appropriate set of input data and parameters is still a research challenge. Considering the above, the aim of this study is to (i) identify the best suitable software for automatic catchment delineation by considering gully grating as outlet (ii) understand the effect of resolution of DEM on catchments delineated (iii) understand whether to consider DEM or DSM for catchment delineation (iv) study the effect of grid based and TIN based DEM. In this study catchment delineation has been investigated considering IIT Kanpur as a study site. LiDAR data are used to generate DEM/DSM of the study area. A comparative study of catchment delineation has been carried out between ArcHydro 10.1, BASINS 4.1, ArcSWAT, WMS 7.1, and HEC-GeoHMS approaches. Catchments have been delineated for different drainage threshold areas using gully grating points as outlets and their effects have been compared for the aforementioned software. In order to understand the effect of resolution of data, DEMs of 1m and 5m resolution have been generated and compared against each other. Effects of building ridge lines and their contribution to catchment delineation has been studied by generating a DSM of 1m resolution, and comparing the results with catchments delineated using 1m DEM. In order to assess the effects of the types of DEM over catchment delineation, a grid based DEM and TIN based DEM are compared against each other using WMS 7.1 software. The results for the catchment delineation using various software illustrate that ArcHydro 10.1 performs better than any other aforementioned software. Also, it is noted that varied drainage threshold area parameters, resolutions of DEM, selection of DEM

  14. Catchment Systems Engineering: A New Paradigm in Water Management

    NASA Astrophysics Data System (ADS)

    Quinn, P. F.; Wilkinson, M. E.; Burke, S.; O'Donnell, G. M.; Jonczyk, J.; Barber, N.; Nicholson, A.

    2012-04-01

    Recent catchment initiatives have highlighted the need for new holistic approaches to sustainable water management. Catchment Systems Engineering seeks to describe catchment the function (or role) as the principal driver for evaluating how it should be managed in the future. Catchment Systems Engineering does not seek to re-establish a natural system but rather works with natural processes in order to engineer landscapes to accrue multiple benefits. The approach involves quantifying and assessing catchment change, impacts and most importantly, suggests an urgent and proactive agenda for future planning. In particular, an interventionist approach to managing hydrological flow pathways across scale is proposed. It is already accepted that future management will require a range of scientific expertise and full engagement with stakeholders. This inclusive concept under a Catchment Systems Engineering agenda forces any consortia to commit to actively changing and perturbing the catchment system and thus learn, in situ, how to manage the environment for collective benefits. The shared cost, the design, the implementation, the evaluation and any subsequent modifications should involve all relevant parties in the consortia. This joint ownership of a 'hands on' interventionist agenda to catchment change is at the core of Catchment Systems Engineering. In this paper we show a range of catchment engineering projects from the UK that have addressed multi-disciplinary approaches to flooding, pollution and ecosystem management, whilst maintaining economic food production. Examples using soft engineered features such as wetlands, ponds, woody debris dams and infiltration zones will be shown. Local scale demonstration activities, led by local champions, have proven to be an effective means of encouraging wider uptake. Evidence that impacts can be achieved at local catchment scale will be introduced. Catchment Systems Engineering is a concept that relies on all relevant parties

  15. Catchment mixing processes and travel time distributions

    NASA Astrophysics Data System (ADS)

    Botter, Gianluca

    2012-05-01

    This work focuses on the description and the use of the probability density functions (pdfs) of travel, residence and evapotranspiration times, which are comprehensive descriptors of the fate of rainfall water particles traveling through catchments, and provide key information on hydrologic flowpaths, partitioning of precipitation, circulation and turnover of pollutants. Exploiting some analytical solutions to the transport problem derived by Botter et al. (2011), this paper analyzes the features of travel, residence and evapotranspiration time pdfs resulting from different assumptions on the mixing processes occurring during streamflow formation and plant uptake (namely, complete mixing and translatory flow). The ensuing analytical solutions are analyzed through numerical Monte Carlo simulations of a stochastic model of soil moisture and streamflow dynamics. Travel and residence time pdfs are shown to be time-variant as they mirror the variability of the relevant hydrological fluxes. In particular, the temporal fluctuations of the mean residence time are shown to reflect rainfall dynamics, whereas the variability of the mean travel time is chiefly driven by streamflow dynamics, with lower frequency and higher amplitude fluctuations. Dry climates enhance the effect of the type of mixing on catchment transport features (e.g., mean travel times and seasonal dynamics of stream concentrations). The implications for the interpretation of tracer experiments are also discussed, showing through specific examples that models disregarding nonstationarity may significantly misestimate travel time pdfs.

  16. Catchment-Scale Conservation Units Identified for the Threatened Yarra Pygmy Perch (Nannoperca obscura) in Highly Modified River Systems

    PubMed Central

    Brauer, Chris J.; Unmack, Peter J.; Hammer, Michael P.; Adams, Mark; Beheregaray, Luciano B.

    2013-01-01

    Habitat fragmentation caused by human activities alters metapopulation dynamics and decreases biological connectivity through reduced migration and gene flow, leading to lowered levels of population genetic diversity and to local extinctions. The threatened Yarra pygmy perch, Nannoperca obscura, is a poor disperser found in small, isolated populations in wetlands and streams of southeastern Australia. Modifications to natural flow regimes in anthropogenically-impacted river systems have recently reduced the amount of habitat for this species and likely further limited its opportunity to disperse. We employed highly resolving microsatellite DNA markers to assess genetic variation, population structure and the spatial scale that dispersal takes place across the distribution of this freshwater fish and used this information to identify conservation units for management. The levels of genetic variation found for N. obscura are amongst the lowest reported for a fish species (mean heterozygosity of 0.318 and mean allelic richness of 1.92). We identified very strong population genetic structure, nil to little evidence of recent migration among demes and a minimum of 11 units for conservation management, hierarchically nested within four major genetic lineages. A combination of spatial analytical methods revealed hierarchical genetic structure corresponding with catchment boundaries and also demonstrated significant isolation by riverine distance. Our findings have implications for the national recovery plan of this species by demonstrating that N. obscura populations should be managed at a catchment level and highlighting the need to restore habitat and avoid further alteration of the natural hydrology. PMID:24349405

  17. Catchment-scale conservation units identified for the threatened Yarra pygmy perch (Nannoperca obscura) in highly modified river systems.

    PubMed

    Brauer, Chris J; Unmack, Peter J; Hammer, Michael P; Adams, Mark; Beheregaray, Luciano B

    2013-01-01

    Habitat fragmentation caused by human activities alters metapopulation dynamics and decreases biological connectivity through reduced migration and gene flow, leading to lowered levels of population genetic diversity and to local extinctions. The threatened Yarra pygmy perch, Nannoperca obscura, is a poor disperser found in small, isolated populations in wetlands and streams of southeastern Australia. Modifications to natural flow regimes in anthropogenically-impacted river systems have recently reduced the amount of habitat for this species and likely further limited its opportunity to disperse. We employed highly resolving microsatellite DNA markers to assess genetic variation, population structure and the spatial scale that dispersal takes place across the distribution of this freshwater fish and used this information to identify conservation units for management. The levels of genetic variation found for N. obscura are amongst the lowest reported for a fish species (mean heterozygosity of 0.318 and mean allelic richness of 1.92). We identified very strong population genetic structure, nil to little evidence of recent migration among demes and a minimum of 11 units for conservation management, hierarchically nested within four major genetic lineages. A combination of spatial analytical methods revealed hierarchical genetic structure corresponding with catchment boundaries and also demonstrated significant isolation by riverine distance. Our findings have implications for the national recovery plan of this species by demonstrating that N. obscura populations should be managed at a catchment level and highlighting the need to restore habitat and avoid further alteration of the natural hydrology. PMID:24349405

  18. Characterising groundwater-dominated lowland catchments: the UK Lowland Catchment Research Programme (LOCAR)

    NASA Astrophysics Data System (ADS)

    Wheater, H. S.; Peach, D.; Binley, A.

    2007-01-01

    This paper reports on a major UK initiative to address deficiencies in understanding the hydro-ecological response of groundwater-dominated lowland catchments. The scope and objectives of this national programme are introduced and focus on one of three sets of research basins - the Pang/Lambourn Chalk catchments, tributaries of the river Thames in southern England. The motivation for the research is the need to support integrated management of river systems that have high ecological value and are subject to pressures that include groundwater abstraction for water supply, diffuse pollution, and land use and climate change. An overview of the research programme is provided together with highlights of some current research findings concerning the hydrological functioning of these catchments. Despite the importance of the Chalk as a major UK aquifer, knowledge of the subsurface movement of water and solutes is poor. Solute transport in the dual porosity unsaturated zone depends on fracture/matrix interactions that are difficult to observe; current experimental and modelling research supports the predominance of matrix flow and suggests that slow migration of a time-history of decades of nutrient loading is occurring. Groundwater flows are complex; catchments vary seasonally and are ill-defined and karst features are locally important. Groundwater flow pathways are being investigated using natural and artificial geochemical tracers based on experimental borehole arrays; stream-aquifer interaction research is using a combination of geophysics, borehole array geochemistry and longitudinal profiles of stream flow and solutes. A complex picture of localised subsurface inflows, linked to geological controls and karst features, and significant longitudinal groundwater flow below the river channel is emerging. Management implications are discussed. Strategies to control surface application of nutrients are expected to have little effect on groundwater quality for several

  19. Modelling soil erosion and associated sediment yield for small headwater catchments of the Daugava spillway valley, Latvia

    NASA Astrophysics Data System (ADS)

    Soms, Juris

    2015-04-01

    The accelerated soil erosion by water and associated fine sediment transfer in river catchments has various negative environmental as well as economic implications in many EU countries. Hence, the scientific community had recognized and ranked soil erosion among other environmental problems. Moreover, these matters might worsen in the near future in the countries of the Baltic Region, e.g. Latvia considering the predicted climate changes - more precisely, the increase in precipitation and shortening of return periods of extreme rainfall events, which in their turn will enable formation of surface runoff, erosion and increase of sediment delivery to receiving streams. Thereby it is essential to carry out studies focused on these issues in order to obtain reliable data in terms of both scientific and applied aims, e.g. environmental protection and sustainable management of soils as well as water resources. During the past decades, many of such studies of soil erosion had focused on the application of modelling techniques implemented in a GIS environment, allowing indirectly to estimate the potential soil losses and to quantify related sediment yield. According to research results published in the scientific literature, this approach currently is widely used all over the world, and most of these studies are based on the USLE model and its revised and modified versions. Considering that, the aim of this research was to estimate soil erosion rates and sediment transport under different hydro-climatic conditions in south-eastern Latvia by application of GIS-based modelling. For research purposes, empirical RUSLE model and ArcGIS software were applied, and five headwater catchments were chosen as model territories. The selected catchments with different land use are located in the Daugava spillway valley, which belongs to the upper Daugava River drainage basin. Considering lithological diversity of Quaternary deposits, a variety of soils can be identified, i.e., Stagnic

  20. A flexible multi-model framework for catchment-specific calibration, and application to diverse European catchments

    NASA Astrophysics Data System (ADS)

    Kavetski, Dmitri; Fenicia, Fabrizio; Savenije, Hubert H. G.

    2010-05-01

    If one accepts that a single model structure cannot accommodate the wide spectrum of catchment dynamics encountered in practice, the need for flexible hydrological models becomes evident. Here, we present SUPERFLEX, a hydrological modelling system that represent the catchment as a network of conceptual elements, including nonlinear reservoirs and routing components, with connectivity, constitutive relations and parameterizations specified by the Hydrologist using a priori insights into the catchment of interest, and refined based on calibration results. The model equations are implemented using robust numerical approaches, and the entire SUPERFLEX system is integrated into a Bayesian inference suite, permitting hypotheses regarding forcing/response data to be evaluated and refined as part of the model inference. The application of the SUPERFLEX approach to a range of European catchments is presented, demonstrating how the ability to adjust the model structure to specific catchments allows improved representatation of its key hydrological processes, and consequently improved model performance.

  1. Thrombotic thrombocytopenic purpura in southeastern New England.

    PubMed

    Crowley, J P; Zaroulis, C G; O'Shea, P A; Clark, D D

    1983-05-01

    Eight patients with thrombotic thrombocytopenic purpura (TTP) originating within a 25-mile radius had their conditions diagnosed in a three-year period at a community teaching hospital in southeastern New England. In the preceding ten years, only one case of TTP had occurred in the same hospital. A niece-uncle relationship was present in two patients, and lymphocyte typing showed that they both shared an HLA haplotype. In the remaining patients, no social, familial, or environmental connection was established. Three patients died, all of whom were female. Six patients received exchange plasmapheresis with excellent responses in five. Autopsies in the three fatal cases showed widespread organ involvement with TTP but did not disclose evidence of any common underlying disease. This unusual occurrence should alert physicians to the possibility of localized outbreaks of TTP and the necessity of considering this diagnosis in all patients with unexplained thrombocytopenia. PMID:6383244

  2. Climate Dynamics of Regional US Southeastern drought

    NASA Astrophysics Data System (ADS)

    Arrigo, J.

    2008-12-01

    The phenomena of droughts both regional and continental have received considerable attention from both science and policy. Understanding the larger scale dynamics of these events is critical to improving predictability, management and mitigation strategies. The history of drought in the United States shows both long (multi-decadal) and short (seasonal or yearly) droughts in various regions. Some of the most severe droughts, such as those with the largest economic losses or that have received the most attention both from the scientific and broader communities have occurred in the Midwest/Great Plains (e.g. the "Dust Bowl" years, the 1988 drought) and generally correlate with continent-wide anomalies. The Southeast region of the US, while generally having a more humid temperature climate than the rest of the country, also is subject to periods of drought conditions. In this study we analyze long term records of PDSI in the southeastern United States. While some occurrences correlate with larger continental scale droughts, many severe southeastern droughts occur during a synoptic pattern correlating with wetter conditions through the greater Midwest, have a seasonal pattern different than larger continental scale anomalies, and show correlations with patterns in Atlantic tropical activity. While winter and spring deficits may initiate a drought, we find a proportionally larger decrease in summertime precipitation during severe drought periods. Some of this decrease may be related to the contribution of tropical systems, which increases in the periods following droughts. We suggest that the dynamics of drought in this region differ from the larger US pattern, and particularly need to account for the interaction between continental and tropical contributions. With an increasing population and areas of high agricultural productivity, we argue this region deserves further attention from both the scientific and larger community, that understanding these dynamics will

  3. Assessing the ecological condition of streams in a southeastern Brazilian basin using a probabilistic monitoring design.

    PubMed

    Jiménez-Valencia, Juliana; Kaufmann, Philip R; Sattamini, Ana; Mugnai, Riccardo; Baptista, Darcilio Fernandes

    2014-08-01

    Prompt assessment and management actions are required if we are to reduce the current rapid loss of habitat and biodiversity worldwide. Statistically valid quantification of the biota and habitat condition in water bodies are prerequisites for rigorous assessment of aquatic biodiversity and habitat. We assessed the ecological condition of streams in a southeastern Brazilian basin. We quantified the percentage of stream length in good, fair, and poor ecological condition according to benthic macroinvertebrate assemblage. We assessed the risk of finding degraded ecological condition associated with degraded aquatic riparian physical habitat condition, watershed condition, and water quality. We describe field sampling and implementation issues encountered in our survey and discuss design options to remedy them. Survey sample sites were selected using a spatially balanced, stratified random design, which enabled us to put confidence bounds on the ecological condition estimates derived from the stream survey. The benthic condition index indicated that 62 % of stream length in the basin was in poor ecological condition, and 13 % of stream length was in fair condition. The risk of finding degraded biological condition when the riparian vegetation and forests in upstream catchments were degraded was 2.5 and 4 times higher, compared to streams rated as good for the same stressors. We demonstrated that the GRTS statistical sampling method can be used routinely in Brazilian rain forests and other South American regions with similar conditions. This survey establishes an initial baseline for monitoring the condition and trends of streams in the region. PMID:24829159

  4. Knickpoint Propagation and Hillslope Response in the Mangataikapua Catchment, Waipaoa River, New Zealand

    NASA Astrophysics Data System (ADS)

    Cerovski-Darriau, C.; Roering, J. J.; Bilderback, E. L.

    2012-12-01

    Base level change can cause differential incision in fluvial networks, driving a transient hillslope response as slopes attempt to adjust to a new base level. Following a shift to a warmer, wetter climate after the Last Glacial Maximum (LGM) (~17.5 ka), the Waipaoa River (NZ) rapidly incised ~120 m leaving perched relict hillslopes that are still adjusting to that base level fall. While previous studies of the Waipaoa basin have only focused on sediment contribution from channel incision or a few individual large earthflows, here we analyze an entire catchment that experiences widespread adjustment due to earthflow activity. In the Mangataikapua catchment—a tributary of the Waipaoa River principally comprised of weak mélange—we see wholesale relaxation of hillslopes due to pervasive post-LGM earthflows. Less than 6% of the mélange area retains relict terrain unaltered by earthflows, exemplifying the importance of including hillslope sediment contribution. Incision has propagated ~9 km upstream along the mainstem of the Mangataikapua (~86% of the channel length) and has created 80 m of relief at the junction with the Waipaoa. Continued adjustment along Mangataikapua tributaries and slopes is evident from knickpoints in the channels and changes in gradient, curvature, and degree of earthflow-altered terrain on the hillslopes. By identifying the location of this transition in channels and on the hillslopes, we can estimate the amount of post-LGM hillslope relaxation. We analyzed 10 major sub-catchments (drainage areas >35,000 m2) in the mélange on the southeastern side of the catchment. We used slope-area plots, in conjunction with normalized steepness index values (ksn) generated with the Stream Profiler (www.geomorphtools.org), to determine the degree to which the tributary channels have adjusted to incision along the mainstem. Preliminary results show an "upper zone" of relict channel morphology with an average curvature value of θ=-0.3 (±0.1 s.d.) and a

  5. Comparison of drought occurrence in selected Slovak and Czech catchments

    NASA Astrophysics Data System (ADS)

    Fendekova, Miriam; Fendek, Marian; Porubska, Diana; Hanel, Martin; Horacek, Stanislav; Martinkova, Marta; Vizina, Adam

    2014-05-01

    The presented study is focused on the analysis and comparison of hydrological drought occurrence, development and duration in six small to middle sized catchments in the Czech Republic (CZ) and Slovakia. The main questions to be answered are: (1) are there correlations between the physical conditions in the catchments and drought occurrence, and (2) does the spatial trend of drought occurrence exist. The Žitava catchment is located in the central western part of Slovakia having runoff dominated by rainfall with the contribution of snow melting during the spring period. The Belá River catchment is located on the contact of Západné and Vysoké Tatry Mts. in the north of Slovakia. The runoff is snow to snow-rain combined type. The Ľupčianka catchment is located on the northern slopes of the Nízke Tatry Mts. in the northern part of the central Slovakia. The runoff regime is snow-rain combined in the upper part of the catchment, and of rain-snow type in the rest of catchment. The Rakovnický potok brook (CZ) has its spring in Rakovnická pahorkatina hilly land. Runoff is dominated by rainfall, quite heavily influenced by water uptakes in the catchment. The Teplá River (CZ) originates in peat meadows in the western part of the Czech Republic. Runoff is dominated by rainfall. The Metuje catchment (CZ) is formed by Adršsbach-Teplické stěny Upland. The headwater part is typical by deeply incest valleys, table mountains and pseudokarst caves. The discharge is fed dominantly by groundwater. The streamflow drought was characterized using discharge data, the groundwater drought using the base flow values. The local minimum method was used for base flow separation. The threshold level method (Q80, BF80) and the sequent peak algorithm were used for calculation of drought duration in discharge and base flow time series. The data of the same three decades of the common period (1971 - 1980, 1981 - 1990 and 1991 - 2000) were used. The resulting base flow values along with

  6. The application of GEOtop for catchment scale hydrology in Ireland

    NASA Astrophysics Data System (ADS)

    Lewis, C.; Xu, X.; Albertson, J.; Kiely, G.

    2009-04-01

    GEOtop represents the new generation of distributed hydrological model driven by geospatial data (e.g. topography, soils, vegetation, land cover). It estimates rainfall-runoff, evapotranspiration and provides spatially distributed outputs as well as routing water and sediment flows through stream and river networks. The original version of GEOtop designed in Italy, includes a rigorous treatment of the core hydrological processes (e.g. unsaturated and saturated flow and transport, surface energy balances, and streamflow generation/routing). Recently GEOtop was extended to include treatment of shallow landslides. The GEOtop model is built on an open-source programming framework, which makes it well suited for adaptation and extension. GEOtop has been run very successfully in a number of alpine catchments (such as Brenta) but has not been used on Irish catchments before. The cell size used for the spatially distributed inputs varies from catchment to catchment. In smaller catchments (less than 2000ha) 50 by 50m cells have been used and 200 by 200 for larger catchments. Smaller cell sizes have been found to significantly increase the computational time so a larger cell size is used providing it does not significantly affect the performance of the model. Digital elevation model, drainage direction, landuse and soil type maps are the minimum spatial requirements with precipitation, radiation, temperature, atmospheric pressure and wind speed been the minimum meteorological requirements for a successful run. The soil type maps must also contain information regarding texture and hydraulic conductivity. The first trial of GEOtop in Ireland was on a small 1524 ha catchment in the south of Ireland. The catchment ranges from 50 to just over 200m, the land use is predominately agricultural grassland and it receives on average 1400mm of rain per year. Within this catchment there is a meteorological tower which provides the meteorological inputs, soil moisture is also recorded at

  7. The Hydrologic Response of a Small Catchment to Clear Cutting

    NASA Astrophysics Data System (ADS)

    Abdelnour, A.; Stieglitz, M.; Pan, F.; McKane, R. B.

    2006-12-01

    We simulated how a landscape disturbance (i.e., fire or clear-cutting) alters hillslope and catchment hydrologic processes. Specifically, we simulated how the pattern and magnitude of tree removal in a catchment increases downslope transport of water and alters catchment soil moisture and discharge. The study site is the WS10 catchment of the HJ Andrews LTER, located in the Pacific NorthWest, USA. We used a spatially- explicit hydrologic model comprised of connected landscape units. We implicitly model biomass removal and the subsequent forest re-growth by manipulating evapotranspiration. We allow potential evapotranspiration to increase exponentially from zero at the onset of the disturbance to pre-disturbance values within a 40 years period. Simulations show that while soil moisture in the uplands increased in post-disturbance period, downslope flow increased only minimally. In this catchment, upland soil moisture stayed well below field capacity, and therefore, downslope lateral flow was not initiated. As such, midland and lowland soil moisture, as well as catchment discharge, remained near pre-disturbance values throughout the re-growth period. This behavior in catchment dynamics resulted primarily from the fact that seasonal temperatures and precipitations are out of phase in this region of the US.

  8. Modeling of matters removal from swampy catchment

    NASA Astrophysics Data System (ADS)

    Inishev, N. G.; Inisheva, L. I.

    2010-05-01

    This work shows the results of fixed study of geochemical conditions in the system of landscape oligotrophic profile at Vasyugan mire spurs, and also we make an approach to processes modelling of compounds removal from swampy catchment. During investigation of symbolic model of chemical matters removal from the surface of a catchment basin and their movement along the channel network it was taken into account that removal of chemical elements during the period of spring flood and rain high waters occur mainly with overland flow. During calculation of dissolved matters movement the following admissions take place: 1. The problem is solved at one-dimension set-up. Concentration of investigated components is taken as averaged one along the flow cross section or effective area of slope cross-section for overland runoff, i.e. it changes only lengthways and in time. 2. It is considered that dissolved matters spread due to movement of water and together with its particles. 3. Processes of water self-clarification are not considered. The model is calculated on the basis of discharge of the investigated ingredient, i.e. matter mass moving through the given flow cross-section into time unit. This is the peculiarity of the model. Matter removal together with water flow is determined if necessary. Everyday impurity consumptions and its concentration can be estimated at the outlet at the moment of time according to convolution integral. Estimation of overland runoff and water inflow into the channel network is based on the mathematic model of outflow formation from peatland areas which considers basic processes carrying out at catchment and basin channel network. Stored moisture estimation of snow cover is taken according to snow survey data before snow melting. Everyday water supply to the surface of water collection was determined according to the results of snow melt intensity estimation by the methods of temperature coefficient and water yield from snow (A.G. Kovzel). All

  9. Chemical weathering and runoff chemistry in a steep headwater catchment

    NASA Astrophysics Data System (ADS)

    Anderson, Suzanne Prestrud; Dietrich, William E.

    2001-07-01

    We present here deductions about the location, rate, and mechanisms of chemical weathering in a small catchment based on a catchment-scale sprinkling experiment. In this experiment demineralized water was applied at an approximately steady rate in the CB1 catchment in the Oregon Coast Range to reach and maintain a quasi-steady discharge for a period of 4 days. Because of nearly steady flow conditions within the catchment, the contribution to solute fluxes from soil and bedrock could be partitioned. One half of the solute flux from the catchment derived from colluvial soil, and one half from weathering in bedrock. This implies more intense weathering in the thin colluvium mantling the catchment than in the thick underlying weathered bedrock. The annual solute flux from the catchment, scaled to the annual runoff from the catchment, is 32 +/- 10 t km-2 year-1, equivalent to published chemical denudation rates for nearby rivers with drainage areas 106 times greater than the experiment site. Soil waters sampled during the sprinkling experiment had steady compositions following a period of transient water flow conditions, implying steady-state chemical evolution in the soil. The waters leached organic anions from shallow depths in the soil, which solubilized aluminium and iron, indicating that podzolization is occurring in these soils. Carbonate dissolution appears to be an important source of solutes from the bedrock, despite being present as only a minor phase in the rock. Water balance suggests that the residence time of water in the catchment is about 2 months, and that typical 24 h storms displace only a fraction of the stored water. A consequence is that runoff chemistry is dominated by old water, which imposes strong limits on the variability of runoff composition.

  10. Catchments of general practice in different countries– a literature review

    PubMed Central

    2014-01-01

    The purpose of this paper is to review the current research on catchment areas of private general practices in different developed countries because healthcare reform, including primary health care, has featured prominently as an important political issue in a number of developed countries. The debates around health reform have had a significant health geographic focus. Conceptually, GP catchments describe the distribution, composition and profile of patients who access a general practitioner or a general practice (i.e. a site or facility comprising one or more general practitioners). Therefore, GP catchments provide important information into the geographic variation of access rates, utilisation of services and health outcomes by all of the population or different population groups in a defined area or aggregated area. This review highlights a wide range of diversity in the literature as to how GP catchments can be described, the indicators and measures used to frame the scale of catchments. Patient access to general practice health care services should be considered from a range of locational concepts, and not necessarily constrained by their place of residence. An analysis of catchment patterns of general practitioners should be considered as dynamic and multi-perspective. Geographic information systems provide opportunities to contribute valuable methodologies to study these relationships. However, researchers acknowledge that a conceptual framework for the analysis of GP catchments requires access to real world data. Recent studies have shown promising developments in the use of real world data, especially from studies in the UK. Understanding the catchment profiles of individual GP surgeries is important if governments are serious about patient choice being a key part of proposed primary health reforms. Future health planning should incorporate models of GP catchments as planning tools, at the micro level as well as the macro level, to assist policies on the

  11. Uncertainty in hydrological signatures for gauged and ungauged catchments

    NASA Astrophysics Data System (ADS)

    Westerberg, Ida K.; Wagener, Thorsten; Coxon, Gemma; McMillan, Hilary K.; Castellarin, Attilio; Montanari, Alberto; Freer, Jim

    2016-03-01

    Reliable information about hydrological behavior is needed for water-resource management and scientific investigations. Hydrological signatures quantify catchment behavior as index values, and can be predicted for ungauged catchments using a regionalization procedure. The prediction reliability is affected by data uncertainties for the gauged catchments used in prediction and by uncertainties in the regionalization procedure. We quantified signature uncertainty stemming from discharge data uncertainty for 43 UK catchments and propagated these uncertainties in signature regionalization, while accounting for regionalization uncertainty with a weighted-pooling-group approach. Discharge uncertainty was estimated using Monte Carlo sampling of multiple feasible rating curves. For each sampled rating curve, a discharge time series was calculated and used in deriving the gauged signature uncertainty distribution. We found that the gauged uncertainty varied with signature type, local measurement conditions and catchment behavior, with the highest uncertainties (median relative uncertainty ±30-40% across all catchments) for signatures measuring high- and low-flow magnitude and dynamics. Our regionalization method allowed assessing the role and relative magnitudes of the gauged and regionalized uncertainty sources in shaping the signature uncertainty distributions predicted for catchments treated as ungauged. We found that (1) if the gauged uncertainties were neglected there was a clear risk of overconditioning the regionalization inference, e.g., by attributing catchment differences resulting from gauged uncertainty to differences in catchment behavior, and (2) uncertainty in the regionalization results was lower for signatures measuring flow distribution (e.g., mean flow) than flow dynamics (e.g., autocorrelation), and for average flows (and then high flows) compared to low flows.

  12. Catchment Classification via Hydrologic Modeling: Evaluating the Relative Importance of Model Selection, Parameterization and Classification Techniques

    NASA Astrophysics Data System (ADS)

    Marshall, L. A.; Smith, T. J.; To, L.

    2015-12-01

    Classification has emerged as an important tool for evaluating the runoff generating mechanisms in catchments and for providing a basis on which to group catchments having similar characteristics. These methods are particularly important for transferring models from one catchment to another in the case of data scarce regions or paired catchment studies .In many cases, the goal of catchment classification is to be able to identify models or parameter sets that could be applied to similar catchments for predictive purposes. A potential impediment to this goal is the impact of error in both the classification technique and the hydrologic model. In this study, we examine the relationship between catchment classification, hydrologic models, and model parameterizations for the purpose of transferring models between similar catchments. Building on previous work using a data set of over 100 catchments from south-east Australia, we identify several hydrologic model structures and calibrate each model for each catchment. We use clustering to identify groups of catchments with similar hydrologic response (as characterized through the calibrated model parameters). We examine the dependency of the clustered catchment groups on the pre-selected model, the uncertainty in the calibrated model parameters, and the clustering or classification algorithm. Further, we investigate the relationship between the catchment clusters and certain catchment physical characteristics or signatures, which are more typically used for catchment classification. Overall, our work is aimed at elucidating the potential sources of uncertainty in catchment classification, and the utility of classification for improving hydrologic predictions.

  13. A learning framework for catchment erosion modelling

    NASA Astrophysics Data System (ADS)

    Freer, J. E.; Quinton, J.

    2006-12-01

    Erosion modelling at the catchment scale, like many other disciplines that model environmental signals, is not an exact science. We are limited by our incomplete perceptual understanding of relevant processes; in formulating and simplifying these perceptions into conceptual models; and by our ability to collect data at the right resolution and spatial scale to drive and evaluate our models effectively. The challenge is how to develop models which take into account our difficulties in describing processes, parameterising equations and demonstrating that they perform within acceptable limits. In this talk we will: examine how limited data has been used to develop algorithms applied across the world and how this may lead to one source of prediction error discuss the use of uncertainty analysis techniques for describing the possible suite of model predictions that give acceptable responses explore what field observations can tell us about model performance and how these might be used to constrain uncertainties in model predictions or in some cases contribute towards these uncertainties; consider how we might learn from our data to produce models with an appropriate degree of complexity We hope that the talk will begin a debate about our ability to capture the essence of erosional processes and quantities for storm responses through data and modelling that includes characterising the appropriate level of uncertainties. We will use examples from the literature as well as from our own observations and modelling initiatives. We hope to generate some lively discussion about the limits of our observations to both inform and to evaluate, to consider what the appropriate level of complexity should be for catchment scale erosion modelling and to consider ways to develop a learning framework for all erosion scientists to engage in.

  14. Phenology and global warming research in Brazil

    NASA Astrophysics Data System (ADS)

    Morellato, L. P. C.

    2009-04-01

    A recent review on South American phenology research has shown an increase in phenology papers over the last two decades, especially in this new 21st century. Nevertheless, there is a lack of long term data sets or monitoring systems, or of papers addressing plant phenology and global warming. The IPCC AR4 report from 2007 has offered indisputable evidence of regional to global-scale change in seasonality, but it is supported by plant and animal phenological data from North Hemisphere and temperate species. Information from tropical regions in general and South America in particular are sparse or lacking. Here I summarize the recent outcomes of our ongoing tropical phenology research in Brazil and its potential contribution to integrate fields and understand the effects of global warming within the tropics. The Phenology Laboratory (UNESP) is located at Rio Claro, São Paulo State, Southeastern Brazil. We are looking for trends and shifts on tropical vegetation phenology, and are exploring different methods for collecting and analyzing phenology data. The phenological studies are developed in collaboration with graduate and undergraduate students, post-docs and researchers from Brazil and around the world. We established three long term monitoring programs on Southeastern Brazil from 2000 onwards: trees from an urban garden, semideciduous forest trees, and savanna cerrado woody vegetation, all based on direct weekly to monthly observation of marked plants. We have collected some discontinuous data from Atlantic rain forest trees ranging from 5 to 8 years long. I collaborate with the longest tropical wet forest phenology monitoring system in Central Amazon, and with another long term monitoring system on semi deciduous forest from South Brazil. All research programs aim, in the long run, to monitor and detect shifts on tropical plant phenology related to climatic changes. Our first preliminary findings suggest that: (i) flowering and leafing are more affected by

  15. First report on the whitefly, Aleurodicus pseudugesii on the coconut palm, Cocos nucifera in Brazil.

    PubMed

    de Omena, Rose Paula Mendonça; Guzzo, Elio Cesar; Ferreira, Joana Maria Santos; de Mendonça, Fernando Antônio Cavalcante; de Lima, Aurino Florencio; Racca-Filho, Francisco; Santana, Antônio Euzébio Goulart

    2012-01-01

    The coconut palm, Cocos nucifera L. (Arecales: Arecaceae), is currently grown extensively throughout the intertropical zones of the world, including Brazil, where it constitutes an important source of income for growers. Although whiteflies are not normally considered coconut pests, these insects can damage crops directly by sucking the sap, which weakens the plant; indirect damage may be caused by sooty mold formation over the excreted honeydew and by the transmission of pathogens. Whiteflies have infested coconut plants in the northeastern, northern, and southeastern regions of Brazil. Infested materials were collected and the causative insect was identified as Aleurodicus pseudugesii Martin (Hemiptera: Aleyrodidae). This is the first report of A. pseudugesii in Brazil as a pest of the coconut palm. PMID:22958126

  16. First Report on the Whitefly, Aleurodicus pseudugesii on the Coconut Palm, Cocos nucifera in Brazil

    PubMed Central

    de Omena, Rose Paula Mendonça; Guzzo, Elio Cesar; Ferreira, Joana Maria Santos; de Mendonça, Fernando Antônio Cavalcante; de Lima, Aurino Florencio; Racca-Filho, Francisco; Santana, Antônio Euzébio Goulart

    2012-01-01

    The coconut palm, Cocos nucifera L. (Arecales: Arecaceae), is currently grown extensively throughout the intertropical zones of the world, including Brazil, where it constitutes an important source of income for growers. Although whiteflies are not normally considered coconut pests, these insects can damage crops directly by sucking the sap, which weakens the plant; indirect damage may be caused by sooty mold formation over the excreted honeydew and by the transmission of pathogens. Whiteflies have infested coconut plants in the northeastern, northern, and southeastern regions of Brazil. Infested materials were collected and the causative insect was identified as Aleurodicus pseudugesii Martin (Hemiptera: Aleyrodidae). This is the first report of A. pseudugesii in Brazil as a pest of the coconut palm. PMID:22958126

  17. Zika virus in Brazil and the danger of infestation by Aedes (Stegomyia) mosquitoes.

    PubMed

    Marcondes, Carlos Brisola; Ximenes, Maria de Fátima Freire de Melo

    2016-02-01

    Zika virus, already widely distributed in Africa and Asia, was recently reported in two Northeastern Brazilian: State of Bahia and State of Rio Grande do Norte, and one Southeastern: State of São Paulo. This finding adds a potentially noxious virus to a list of several other viruses that are widely transmitted by Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus in Brazil. The pathology and epidemiology, including the distribution and vectors associated with Zika virus, are reviewed. This review is focused on viruses transmitted by Aedes (Stegomyia) mosquitoes, including dengue, Chikungunya, Zika, Mayaro, and yellow fever virus, to emphasize the risks of occurrence for these arboviruses in Brazil and neighboring countries. Other species of Aedes (Stegomyia) are discussed, emphasizing their involvement in arbovirus transmission and the possibility of adaptation to environments modified by human activities and introduction in Brazil. PMID:26689277

  18. Eosinophilic meningitis caused by Angiostrongylus cantonensis: an emergent disease in Brazil

    PubMed Central

    Morassutti, Alessandra Loureiro; Thiengo, Silvana Carvalho; Fernandez, Monica; Sawanyawisuth, Kittisak; Graeff-Teixeira, Carlos

    2014-01-01

    Eosinophilic meningitis (EoM) is an acute disease that affects the central nervous system. It is primarily caused by infection with the nematode Angiostrongylus cantonensis. This infection was previously restricted to certain Asian countries and the Pacific Islands, but it was first reported in Brazil in 2007. Since then, intermediate and definitive hosts infected with A. cantonensis have been identified within the urban areas of many states in Brazil, including those in the northern, northeastern, southeastern and southern regions. The goals of this review are to draw the attention of the medical community and health centres to the emergence of EoM in Brazil, to compile information about several aspects of the human infection and mode of transmission and to provide a short protocol of procedures for the diagnosis of this disease. PMID:25075779

  19. Modelling catchment areas for secondary care providers: a case study.

    PubMed

    Jones, Simon; Wardlaw, Jessica; Crouch, Susan; Carolan, Michelle

    2011-09-01

    Hospitals need to understand patient flows in an increasingly competitive health economy. New initiatives like Patient Choice and the Darzi Review further increase this demand. Essential to understanding patient flows are demographic and geographic profiles of health care service providers, known as 'catchment areas' and 'catchment populations'. This information helps Primary Care Trusts (PCTs) to review how their populations are accessing services, measure inequalities and commission services; likewise it assists Secondary Care Providers (SCPs) to measure and assess potential gains in market share, redesign services, evaluate admission thresholds and plan financial budgets. Unlike PCTs, SCPs do not operate within fixed geographic boundaries. Traditionally, SCPs have used administrative boundaries or arbitrary drive times to model catchment areas. Neither approach satisfactorily represents current patient flows. Furthermore, these techniques are time-consuming and can be challenging for healthcare managers to exploit. This paper presents three different approaches to define catchment areas, each more detailed than the previous method. The first approach 'First Past the Post' defines catchment areas by allocating a dominant SCP to each Census Output Area (OA). The SCP with the highest proportion of activity within each OA is considered the dominant SCP. The second approach 'Proportional Flow' allocates activity proportionally to each OA. This approach allows for cross-boundary flows to be captured in a catchment area. The third and final approach uses a gravity model to define a catchment area, which incorporates drive or travel time into the analysis. Comparing approaches helps healthcare providers to understand whether using more traditional and simplistic approaches to define catchment areas and populations achieves the same or similar results as complex mathematical modelling. This paper has demonstrated, using a case study of Manchester, that when estimating

  20. Soilwater dynamics related to waterlogging in a sloping catchment

    NASA Astrophysics Data System (ADS)

    Atputhanathan, C. S.; Gunawardena, E. R. N.; Rushton, K. R.

    1991-03-01

    A study to understand the factors contributing to waterlogging was conducted in a small catchment of 5.4 ha in an irrigation scheme in the Eastern Dry Zone of Sri Lanka. An analysis, based on climatological data, extensive measurements of inflows and outflows, groundwater head fluctuations, soil moisture content variations and soil properties, indicated that a single catchment water balance and the SEW index are of limited value due to the spatial nature of the waterlogging problem in this sloping catchment with surface irregularities. A distributed mathematical model was developed to represent the lateral and vertical components of flow; the agreement between the simulated and field results is satisfactory.

  1. Holocene sediments within lake catchments - testing sediment delivery

    NASA Astrophysics Data System (ADS)

    Dreibrodt, S.; Bork, H.-R.

    2009-04-01

    Results of detailed investigation of soils, colluvia and lake sediments in a lake catchment in northern Germany proves that the input of eroded soil (enabled by agricultural land use) is of a minor amount compared with the storage within colluvial layers. Pre-existing micro- and meso-topography and prehistorical land use patterns as well as precipitation intensity are probable to control the Holocene flux of sediments within the lake catchment area. Therefore we entertain some doubt if sediment delivery ratios- usually applied on larger spatial scales (e. g. river catchment areas)- are useful to produce reliable quantitative data of Holocene soil erosion in central Europe.

  2. Uranium deposits of Brazil

    SciTech Connect

    1991-09-01

    Brazil is a country of vast natural resources, including numerous uranium deposits. In support of the country`s nuclear power program, Brazil has developed the most active uranium industry in South America. Brazil has one operating reactor (Angra 1, a 626-MWe PWR), and two under construction. The country`s economic challenges have slowed the progress of its nuclear program. At present, the Pocos de Caldas district is the only active uranium production. In 1990, the Cercado open-pit mine produced approximately 45 metric tons (MT) U{sub 3}O{sub 8} (100 thousand pounds). Brazil`s state-owned uranium production and processing company, Uranio do Brasil, announced it has decided to begin shifting its production from the high-cost and nearly depleted deposits at Pocos de Caldas, to lower-cost reserves at Lagoa Real. Production at Lagoa Real is schedules to begin by 1993. In addition to these two districts, Brazil has many other known uranium deposits, and as a whole, it is estimated that Brazil has over 275,000 MT U{sub 3}O{sub 8} (600 million pounds U{sub 3}O{sub 8}) in reserves.

  3. River Styles, a Geomorphic Approach to Catchment Characterization: Implications for River Rehabilitation in Bega Catchment, New South Wales, Australia.

    PubMed

    Brierley; Fryirs

    2000-06-01

    / Geomorphologically derived river styles provide an integrative framework for examining the interactions of biophysical processes in rivers throughout a drainage basin. Nine styles of river character and behavior are identified in Bega catchment, on the south coast of New South Wales, Australia. Headwater streams above the escarpment drain into gorges in the escarpment zone. In different subcatchments at the base of the escarpment, there are three different river styles, namely cut-and-fill, vertically accreted floodplains, and fans. Downstream of these river styles, in the rounded foothills of the catchment, throughput and transfer river styles convey sediments to the lowland plain. In one mid-catchment setting, a floodout traps sediment. Finally, along the lowland plain of Bega River, there is a floodplain accumulation river style. Downstream patterns of river styles in differing subcatchments of the Bega River basin are differentiated into three types, reflecting river adjustments to valley width, slope, and responses to human disturbance. Analysis of the character and condition of each river style in Bega catchment, and their downstream patterns, are used to provide a biophysical basis to prioritorize river management strategies. These reach-scale strategies are prioritorized within an integrative catchment framework. Conserving near-intact sections of the catchment is the first priority. Second, those parts of the catchment that have natural recovery potential are targeted. Finally, rehabilitation priorities are considered for highly degraded reaches. At these sites, erosion and sedimentation problems may reflect irreversible changes to river structure. PMID:10790530

  4. 11. NORTH VIEW OF INNER FACING OF SOUTHEASTERN LEG OF ...

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

    11. NORTH VIEW OF INNER FACING OF SOUTHEASTERN LEG OF SEA WALL. SOUTHERN END OF NORTHEASTERN LEG OF SEA WALL IN BACKGROUND. - Fort Delaware, Sea Wall, Pea Patch Island, Delaware City, New Castle County, DE

  5. ESTIMATING AND PROJECTING IMPERVIOUS COVER IN THE SOUTHEASTERN UNITED STATES

    EPA Science Inventory

    Urban/suburban land use constitutes the fastest growing land use class in the Southeastern United States. Predominant development practices increase impervious surface--areas preventing infiltration of water into the underlying soil. Uncontrolled increase of impervious areas (ro...

  6. 8. Detail, lower chord, looking west from southeastern abutment ...

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

    8. Detail, lower chord, looking west from southeastern abutment - Hayden Bridge, Spanning McKenzie River at Southern Pacific Railroad (moved from Springfield, Lake County, OR), Springfield, Lane County, OR

  7. 6. EAST CORNERShowing alley (southeastern) side and front. The Sixteenth ...

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

    6. EAST CORNER--Showing alley (southeastern) side and front. The Sixteenth Street Mall is in the foreground. West - Empire Building, 430 Sixteenth Street, South Corner of Sixteenth Street & Glenarm Place, Denver, Denver County, CO

  8. ESTIMATING AND PROJECTING IMPERVIOUS COVER IN THE SOUTHEASTERN UNITED STATES

    EPA Science Inventory

    Urban/suburban land constitutes the fastest growing land use class in the Southeastern United States. Predominant development practices increase impervious surface--areas preventing infiltration of water into the underlying soil. Uncontrolled increase of impervious areas (roads,...

  9. 10. REINFORCED CONCRETE SLAB ROOF FROM SOUTHEASTERN EDGE, ACCESS RAMPS ...

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

    10. REINFORCED CONCRETE SLAB ROOF FROM SOUTHEASTERN EDGE, ACCESS RAMPS AT LEFT AND RIGHT, VIEW TOWARDS NORTHWEST. - Glenn L. Martin Company, Titan Missile Test Facilities, Captive Test Stand D-1, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  10. INVASION DYNAMICS OF RED SHINERS (CYPRINELLA LUTRENSIS) IN SOUTHEASTERN STREAMS

    EPA Science Inventory

    Red shiners have invaded a range of North American ecosystems, including several southeastern U.S. river drainages. A principle consequence of these invasions is extirpation of native congeners, either through competition or hydridization. We are conducting research to identify...

  11. Uranium assessment for the Precambrian pebble conglomerates in southeastern Wyoming

    SciTech Connect

    Borgman, L.E.; Sever, C.; Quimby, W.F.; Andrew, M.E.; Karlstrom, K.E.; Houston, R.S.

    1981-03-01

    This volume is a geostatistical resource estimate of uranium and thorium in quartz-pebble conglomerates, and is a companion to Volume 1: The Geology and Uranium Potential to Precambrian Conglomerates in the Medicine Bow Mountains and Sierra Madre of Southeastern Wyoming; and to Volume 2: Drill-Hole Data, Drill-Site Geology, and Geochemical Data from the Study of Precambrian Uraniferous Conglomerates of the Medicine Bow Mountains and the Sierra Madre of Southeastern Wyoming.

  12. Impact of possible climate and land use changes in the semi arid regions: A case study from North Eastern Brazil

    NASA Astrophysics Data System (ADS)

    Montenegro, Suzana; Ragab, Ragab

    2012-04-01

    SummaryThis paper combines hydrological observations and modelling results of a semi arid catchment in Brazil that could lead to a better understanding of the hydrology of similar catchments in semi-arid regions. The Tapacurá catchment (area 470.5 km2) in the Northeast of Brazil was selected for this study. The Distributed Catchment Scale Model, DiCaSM, was calibrated and validated for the stream flows of the Tapacurá catchment. The model performance was further tested by comparing simulated and observed scaled soil moisture. The results showed the ability of the model to simulate the stream flow and the scaled soil moisture. The simulated impacts of climate change of low emission (B1) scenarios, on the worst perspective, indicated the possibility of reduction in surface water availability by -13.90%, -22.63% and -32.91% in groundwater recharge and by -4.98%, -14.28% and -20.58% in surface flows for the time spans 2010-2039, 2040-2069, 2070-2099, respectively. This would cause severe impacts on water supply in the region. Changing the land use, for example by reforestation of part of the catchment area which is currently arable land, would lead to a decrease in both groundwater recharge by -4.2% and stream flow by -2.7%. Changing land use from vegetables to sugar cane would result in decreasing groundwater recharge by almost -11%, and increasing stream flow by almost 5%. The combination of possible impacts of climate change and land use requires a proper plan for water resources management and mitigation strategies.

  13. Investigating dominant processes on small poorly gauged catchments: an inter-comparison approach for catchment similarity study

    NASA Astrophysics Data System (ADS)

    Crabit, Armand; Colin, François; Moussa, Roger; Lagacherie, Philippe

    2010-05-01

    Small catchment scales appear to be relevant to study and manage agricultural uses and their hydrological impacts. Mediterranean small catchment responses are characterised by short duration surface runoff due to intense rainfall events of short duration. Ephemeral streams are common fluvial systems: they are usually dry for most of the year and become particularly active during flood events. This considerably complicates hydrological analysis. Therefore, estimating and predicting runoff for small ungauged (or poorly gauged) catchments appears to be a significant challenge. It would allow to a better understanding of dominant processes in relation with catchment functions (partition, release, storage). According to many authors, classification and similarity concepts, which can be profitably used when the processes are not fully understood, could be conducted as an alternative to complex modelling. This study proposes a new methodology for small poorly gauged catchments to (i) estimate surface runoff and associated uncertainty and (ii) identify dominant functions governing hydrological responses. The work focuses on twelve small agricultural catchments, within the French Mediterranean region, with areas ranging between 0,3 and 1 km2. Water depth at the catchment's outlet and rainfall intensities have been collected at a one-minute data step, from September 2008 to September 2009. The analysis has been conducted on 120 flood events. The first step was to make an inter-catchment comparison based on limited hydrological data considering the associated uncertainty. Estimation of flow velocity for natural ephemeral channel is a difficult task. To assess catchment runoff, flow rate curves were established from water depth using Manning's equation. Innovative field and laboratory experiments have been carried out to estimate Manning's coefficient for typical Mediterranean non-aquatic vegetation types. 72 tests have been realised to analyse the effects of vegetation

  14. A MULTIDISCIPLINARY APPROACH TO STORMWATER MANAGEMENT AT THE catchment SCALE

    EPA Science Inventory

    Stormwater runoff from extensive impervious surfaces in urban and suburban areas has led to human safety risks and stream ecosystem impairment, triggering an interest in catchment-scale retrofit stormwater management. Such stormwater management is of multidisciplinary relevance, ...

  15. A catchment scale water balance model for FIFE

    NASA Technical Reports Server (NTRS)

    Famiglietti, J. S.; Wood, E. F.; Sivapalan, M.; Thongs, D. J.

    1992-01-01

    A catchment scale water balance model is presented and used to predict evaporation from the King's Creek catchment at the First ISLSCP Field Experiment site on the Konza Prairie, Kansas. The model incorporates spatial variability in topography, soils, and precipitation to compute the land surface hydrologic fluxes. A network of 20 rain gages was employed to measure rainfall across the catchment in the summer of 1987. These data were spatially interpolated and used to drive the model during storm periods. During interstorm periods the model was driven by the estimated potential evaporation, which was calculated using net radiation data collected at site 2. Model-computed evaporation is compared to that observed, both at site 2 (grid location 1916-BRS) and the catchment scale, for the simulation period from June 1 to October 9, 1987.

  16. How does spatial variability of climate affect catchment streamflow predictions?

    EPA Science Inventory

    Spatial variability of climate can negatively affect catchment streamflow predictions if it is not explicitly accounted for in hydrologic models. In this paper, we examine the changes in streamflow predictability when a hydrologic model is run with spatially variable (distribute...

  17. Brazil: Xingu River

    Atmospheric Science Data Center

    2013-04-18

    ... title:  Fire and Deforestation near the Xingu River     View Larger Image Numerous fires occurred near the headwaters of the Xingu River and the Xingu Indigenous Peoples' Reserve in Mato Grosso, Brazil, during ...

  18. Quantifying human impacts on catchment sediment yield: A continental approach

    NASA Astrophysics Data System (ADS)

    Vanmaercke, Matthias; Poesen, Jean; Govers, Gerard; Verstraeten, Gert

    2015-07-01

    Both from a scientific and environmental management perspective, there is a large need to assess the magnitude and controlling factors of human impacts on catchment sediment yield. Quantifying this impact is difficult, since it requires knowing both the actual sediment yield (SYa, [t km- 2 y- 1]) as well as the corresponding "pristine" value of a catchment (SYp, [t km- 2 y- 1]; i.e. the sediment yield that can be expected if the catchment was not affected by humans). Here we address this problem by comparing measured SYa values for 165 European catchments that were unaffected by dams or reservoirs with their corresponding SYp, which were predicted using a recently developed regression model. The ratio between these two values is expected to reflect the degree of human impact on catchment sediment yield (HIF). Correlation and partial correlation analyses showed that spatial variability in HIF is mainly explained by differences in land use (i.e. the fraction of arable land) and catchment area. The effect of these two factors was clearly linked in western and central Europe: whereas SYa can be easily 40 times higher than SYp in intensively cultivated small (≤ 1 km2) catchments, the difference is negligible for large (> 1000 km2) catchments with the same land use. While, this concurs with our knowledge that the effects of land use (change) on erosion rates can be buffered at the catchment scale, this study provides a first robust quantification of this effect. Apart from a potential climatic effect (i.e. a correlation between HIF and the average annual air temperature) no other factors could be identified that are significant in explaining observed differences in HIF. This indicates that HIF is mainly controlled by catchment scale and land use, while other factors may be only of secondary importance at an intra-continental scale. Nonetheless, more accurate quantifications of these HIF values and more refined characterizations of the catchments in terms of (historical

  19. Seasonal Variations of Nitrate Concentrations In Agricultural Catchments

    NASA Astrophysics Data System (ADS)

    Martin, C.; Aquilina, L.; Gascuel-Odoux, C.; Molénat, J.; Ruiz, L.

    Nitrate concentrations in streams of agricultural catchments with impervious bedrock often present an interannual variability (due to landuse changes) and a seasonal one. Usually seasonal variations are characterised by high concentrations in winter and low in summer. Some catchments may present intermediate or inverse cycles (high con- centrations in summer). Two hypothesis to explain classical variations of nitrate con- centrations in streams exist: (i) the availibility of nitrate in the soil for leaching and (ii) the temporal variations of the nitrate-rich shallow groundwater. The aim of this study is to explain the occurence of classical or inverse scheme of seasonal variations by testing these two existing hypothesis and proposing an alternative one for inverse cycles. Two catchments with different seasonal variations (KERRIEN catchment : normal cycle, and KERBERNEZ catchment : inverse cycle), located in the South Western French Brittany, were instrumented in 2001 with a set of 22 piezometers in- stalled at different depths and located along the hillslope. The water table dynamic and chemestry (nitrate, chloride, carbon, Rare Earth Elements,...) had been measured weekly during one year. The shallow groundwater of the Kerrien catchment is char- acterised by two lateral domains with a temporal stability of concentrations : the bot- tom land, constantly denitrified, and the upper domain with nitrate concentrations around 60 mg.L(-1) . The Kerbernez catchment is characterised by two vertical domains with a temporal rise of concentrations : the upper domain with nitrate concen- trations around 60 mg.L(-1) , as the Kerrien catchment, and a deeper compartment, with concentrations excedeed 100 to 120 mg.L(-1) of nitrate. On the Kerrien catchment, the classical cycle is due to the most important contribution of the shal- low groundwater in winter. The inverse cycle of the Kerbernez catchment may be due to the most important contribution of the deep compartment in

  20. Microturbellarians (Platyhelminthes and Acoelomorpha) in Brazil: invisible organisms?

    PubMed

    Braccini, J A L; Amaral, S V; Leal-Zanchet, A M

    2016-06-01

    Microturbellarians typically belong to the benthos and may occur in a wide variety of environments. They are abundant in freshwater and marine ecosystems and may occur in moist terrestrial habitats. However, turbellarians are seldom taken into account in studies of biodiversity. Most studies on Brazilian microturbellarians had taxonomical purposes and were done in the years 1940-1950. Thus, information on their occurrence and ecological aspects are dispersed throughout several papers. We intend here to summarize the biogeographical distribution and ecological aspects of microturbellarians recorded for Brazil, indicating the main gaps in their knowledge and possible actions to enhance studies on this group. There are 239 species of microturbellarians registered for Brazil, with records distributed in 12 states. However, just three states located in southern Brazil have records of 94% of microturbellarian species. Thus, knowledge on the systematics and geographical distribution of Brazilian microturbellarians clearly reflect the scientific activity over many years or decades in two states of southeastern and southern Brazil. Considering the scant information on this group in Brazil, which is also the situation of the Neotropical microturbellarians in general, some actions should be proposed. First, it would be necessary to sample in the diverse biomes, as well as in the various river and sea basins, based on standardized sampling protocols. Second, it would be necessary to encourage diverse research groups to include microturbellarians and/or turbellarians in general into biodiversity inventories and studies on community structure of invertebrates. Third, it is necessary to increase the number of research groups on microturbellarians, in order to augment the studies on their morphology, systematics, and ecology. Considering their abundance, species richness and ecological importance in aquatic environments, despite some peculiarities regarding their sampling, sorting

  1. Empirical relations between catchment characteristics and discharge patterns in Sweden

    NASA Astrophysics Data System (ADS)

    Lindström, G.; Dahné, J.; Arheimer, B.

    2012-04-01

    In hydrological modelling it is often assumed that catchment characteristics, such as soil type, vegetation, land-use, slope, altitude and climate influence both the magnitude and dynamics of the water discharge characteristics. This presentation demonstrates an inter-site comparison on similarities and dissimilarities in hydrological response from Swedish unregulated catchments with an area less than 2000 km2. Observed daily time-series for about 20 years from 198 sites were analysed to search for and quantify statistical relationships between catchment characteristics and flow characteristics. A number of flow characteristics were calculated, such as the mean, mean annual maximum, peakiness, skewness and percentiles. The catchments were grouped dependent on catchment characteristics (for example >80% forest). The differences between the discharges from different catchment types were analysed both graphically and statistically. A T-test was performed to see if the mean value for the flow characteristics was significantly different from the rest of the catchments. Following the t-test, a set of box-whisker diagrams were made for visual inspection of the results. The results showed that lake percentage is the most important catchment characteristic for most of the flow characteristics. The effect of lakes was therefore treated separately. For lake-free basins soil type was in general more important than land-use. For instance, coarse soils exhibit a sustained base flow, whereas thin soils and bare rock are characterised by peak flows with short duration. Finally, the presentation will give some examples on how the retrieved empirical information was included in a national modelling approach to simulate spatial variability in Swedish water discharge patterns.

  2. Rainfall, runoff and sediment transport in a Mediterranean mountainous catchment.

    PubMed

    Tuset, J; Vericat, D; Batalla, R J

    2016-01-01

    The relation between rainfall, runoff, erosion and sediment transport is highly variable in Mediterranean catchments. Their relation can be modified by land use changes and climate oscillations that, ultimately, will control water and sediment yields. This paper analyses rainfall, runoff and sediment transport relations in a meso-scale Mediterranean mountain catchment, the Ribera Salada (NE Iberian Peninsula). A total of 73 floods recorded between November 2005 and November 2008 at the Inglabaga Sediment Transport Station (114.5 km(2)) have been analysed. Suspended sediment transport and flow discharge were measured continuously. Rainfall data was obtained by means of direct rain gauges and daily rainfall reconstructions from radar information. Results indicate that the annual sediment yield (2.3 t km(-1) y(-1) on average) and the flood-based runoff coefficients (4.1% on average) are low. The Ribera Salada presents a low geomorphological and hydrological activity compared with other Mediterranean mountain catchments. Pearson correlations between rainfall, runoff and sediment transport variables were obtained. The hydrological response of the catchment is controlled by the base flows. The magnitude of suspended sediment concentrations is largely correlated with flood magnitude, while sediment load is correlated with the amount of direct runoff. Multivariate analysis shows that total suspended load can be predicted by integrating rainfall and runoff variables. The total direct runoff is the variable with more weight in the equation. Finally, three main hydro-sedimentary phases within the hydrological year are defined in this catchment: (a) Winter, where the catchment produces only water and very little sediment; (b) Spring, where the majority of water and sediment is produced; and (c) Summer-Autumn, when little runoff is produced but significant amount of sediments is exported out of the catchment. Results show as land use and climate change may have an important

  3. High-resolution Holocene South American monsoon history recorded by a speleothem from Botuverá Cave, Brazil

    NASA Astrophysics Data System (ADS)

    Bernal, J. P.; Cruz, Francisco W.; Stríkis, Nicolás M.; Wang, Xianfeng; Deininger, Michael; Catunda, Maria Carolina A.; Ortega-Obregón, C.; Cheng, Hai; Edwards, R. Lawrence; Auler, Augusto S.

    2016-09-01

    A Holocene stalagmite from Botuverá Cave, southeastern Brazil was analyzed by LA-ICPMS for Mg/Ca, Sr/Ca, Ba/Ca. The observed variability in the record was demonstrated to be modulated by prior calcite precipitation, and, thus, is interpreted to reflect monsoon intensity. We find that the calcite δ18O is strongly correlated with Sr/Ca, indicating that atmospheric circulation over South America and monsoon intensity have been tightly correlated throughout most of the Holocene, both directly responding to solar precession. Comparison with other contemporaneous high-resolution hydroclimate records reveals that SAMS has shown a degree of complexity during the Holocene not previously detected, with periods where the South American Convergence Zone (SACZ) expanded to cover most of the South American sub-continent, and coincident with periods of low-SST in the north Atlantic. We also detect periods where rainfall amount in northeastern and southeastern Brazil are markedly anti-phased, suggesting a north-south migration of SACZ, which it appears to be mediated by solar irradiance. The high-resolution nature of our record allow us to examine the effect that Holocene climate anomalies had upon SAMS dynamics and hydroclimate in southeastern Brazil, in particular the 8.2 ka event and the Little Ice Age. In addition to confirm the internal structure of the events, we also detect the possible consequences of the climatic anomalies upon ocean-atmosphere interactions through its effects upon SAMS.

  4. Predicting aquifer response time for application in catchment modeling.

    PubMed

    Walker, Glen R; Gilfedder, Mat; Dawes, Warrick R; Rassam, David W

    2015-01-01

    It is well established that changes in catchment land use can lead to significant impacts on water resources. Where land-use changes increase evapotranspiration there is a resultant decrease in groundwater recharge, which in turn decreases groundwater discharge to streams. The response time of changes in groundwater discharge to a change in recharge is a key aspect of predicting impacts of land-use change on catchment water yield. Predicting these impacts across the large catchments relevant to water resource planning can require the estimation of groundwater response times from hundreds of aquifers. At this scale, detailed site-specific measured data are often absent, and available spatial data are limited. While numerical models can be applied, there is little advantage if there are no detailed data to parameterize them. Simple analytical methods are useful in this situation, as they allow the variability in groundwater response to be incorporated into catchment hydrological models, with minimal modeling overhead. This paper describes an analytical model which has been developed to capture some of the features of real, sloping aquifer systems. The derived groundwater response timescale can be used to parameterize a groundwater discharge function, allowing groundwater response to be predicted in relation to different broad catchment characteristics at a level of complexity which matches the available data. The results from the analytical model are compared to published field data and numerical model results, and provide an approach with broad application to inform water resource planning in other large, data-scarce catchments. PMID:24842053

  5. Study of Beijiang catchment flash-flood forecasting model

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Li, J.; Huang, S.; Dong, Y.

    2015-05-01

    Beijiang catchment is a small catchment in southern China locating in the centre of the storm areas of the Pearl River Basin. Flash flooding in Beijiang catchment is a frequently observed disaster that caused direct damages to human beings and their properties. Flood forecasting is the most effective method for mitigating flash floods, the goal of this paper is to develop the flash flood forecasting model for Beijiang catchment. The catchment property data, including DEM, land cover types and soil types, which will be used for model construction and parameter determination, are downloaded from the website freely. Based on the Liuxihe Model, a physically based distributed hydrological model, a model for flash flood forecasting of Beijiang catchment is set up. The model derives the model parameters from the terrain properties, and further optimized with the observed flooding process, which improves the model performance. The model is validated with a few observed floods occurred in recent years, and the results show that the model is reliable and is promising for flash flood forecasting.

  6. Snow Storm Blankets Southeastern U.S.

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A new year's storm brought heavy snow to portions of the southeastern United States, with some regions receiving more than a foot in less than two days. By Friday, January 4, 2002, the skies had cleared, and MODIS captured this false-color image showing the extent of the snowfall. Snow cover is red, and extends all the way from Alabama (lower left), up through Georgia, South Carolina, North Carolina, Virginia, and Maryland, including the southern reaches of the Delmarva Peninsula (upper right). Beneath some clouds in West Virginia (top center), snow is also visible on the Allegheny Mountains and the Appalachian Plateau, although it did come from the same storm. Though red isn't the color we associate with snow, scientists often find 'false-color' images more useful than 'true-color' images in certain situations. True-color images are images in which the satellite data are made to look like what our eyes would see, using a combination of red, green, and blue. In a true-color image of this scene, cloud and snow would appear almost identical-both would be very bright white-and would be hard to distinguish from each other. However, at near-infrared wavelengths of light, snow cover absorbs sunlight and therefore appears much darker than clouds. So a false-color image in which one visible wavelength of the data is colored red, and different near-infrared wavelengths are colored green and blue helps show the snow cover most clearly.

  7. Channel degradation in southeastern Nebraska Rivers

    USGS Publications Warehouse

    Wahl, Kenneth L.; Weiss, Linda S.

    1995-01-01

    Many stream channels in southeastern Nebraska were dredged and straightened during 1904-15. The resulting channels were both shorter and steeper than the original channels. Tests for time trends were conducted using the nonparametric Kendall tau test to see if the channels have responded to these changes. Tests were conducted on the stages associated with specific discharges and on measurement characteristics at gaging stations. Tests also were conducted on hydrologic forcing variables (annual mean precipitation, annual peak discharges, annual mean discharge, and annual mean base flows). The null hypothesis (that the data were free from trend) was rejected for stages associated with the mean of the annual discharges for 6 of 7 gaging stations in the study area, but was accepted for all 3 gages on the main stem of the Missouri River. The trends at the 6 streamflow gaging stations were for decreasing stages (degrading channels) for specific discharges. The rates of change ranged from about 0.2 to 0.5 m per decade. Mean stream bed elevations computed for individual discharge measurements at these streamflow gaging stations confirmed that the channels are degrading. However, neither the precipitation nor flow variables show evidence of trends. The tendency for the channels to degrade thus cannot be attributed to changes in runoff characteristics and are assumed to be a response to the channel modifications in the early 1900's. Indications are that the channels presently are continuing to degrade.

  8. Southeastern Cancer Study Group: breast cancer studies

    SciTech Connect

    Smalley, R.V.; Bartolucci, A.A.; Moore, M.

    1983-12-01

    During the past 10 years, the Southeastern Cancer Study Group (SECSG) has been engaged in one major adjuvant study and three major advanced disease studies for patients with adenocarcinoma of the breast. The adjuvant study is demonstrating that six months of adjuvant CMF is the therapeutic equivalent of 12 months and that post-operative irradiation is of no added therapeutic benefit. In patients with advanced disease, a low dose 5 drug combination of CMFVP induces more objective responses than single agent 5FU, but improves survival only for those patients with liver metastases when compared to the sequential use of the same 5 single agents. The three drug combination, CAF, utilizing doxorubicin, induces more objective responses than low dose CMFVP, but it does not improve overall survival. The addition of a phase active combination, CAMELEON, (i.e., sequentially alternating therapy) of CAF has not improved the duration of disease control and survival for patients with liver metastases, lymphangitic and nodular lung metastases compared to CAF. Aggressive combination chemotherapeutic approaches to patients with advanced disease provide better and longer disease and tumor control but only marginal improvements in overall survival. Adding additional agents to a maximally tolerable regimen has not improved the therapeutic outcome.

  9. Tectonics and terranes of the Southeastern Caribbean

    SciTech Connect

    Speed, R.C. )

    1993-02-01

    The southeastern Caribbean plate (Ca) is comprised of the following terranes: Tobago, Grenada Basin, St. Vincent, Araya-Margarita, and Paria-Trinidad-Barbardos (PTB). All are alient relative to South America (SA) east of Caracas except for PTB, which is of continental provenance and parautochthonous and lies within the principal movement zone of the Ca-Sa plate boundary. The Tobago terrane extends between the eastern Venezuelan coastline and the Grenada Basin. On its south, the Tobago terrane overrode PTB and the South American passive margin during Neogene oblique collision. The Mesozoic tectonostratigraphy of the Tobago terrane is not unlike that of the Colombian Basin, suggesting the Tobago may belong to the Pacific-derived Caribbean plate. The Grenada Basin terrane consists of Eocene and older oceanic crust that now occupies the southern Lesser Antilles arc platform and the southern Grenada Basin. Such crust abducted southward below the Tobago terrane in mid-Cenozoic time, probably taking up boundary-normal shortening during oblique collision of the Ca and Sa plates. The oceanic crust of the GB terrane arose by backarc spreading of unknown orientation. The St. Vincent terrane extends north in the Antilles from St. Vincent; it is defined by thick crust, perhaps an old arc basement. The Araya-Margarita terrane is a probable subduction complex of Mesozoic age of metamorphism that has been transported far eastward from an unknown site with the Ca plate.

  10. Karst in evaporites in southeastern New Mexico

    SciTech Connect

    Bachman, G.O.

    1987-09-01

    Permian evaporites in southeastern New Mexico include gypsum, anhydrite, and salt, which are subject to both blanket and local, selective dissolution. Dissolution has produced many hundreds of individual karst features including collapse sinks, karst valleys, blind valleys, karst plains, caves, and breccia pipes. Dissolution began within some formations during Permian time and has been intermittent but continual ever since. Karst features other than blanket deposits of breccia are not preserved from the early episodes of dissolution, but some karst features preserved today - such as breccia pipes - are remnants of karst activity that was active at least as early as mid-Pleistocene time. Rainfall was much more abundant during Late Pleistocene time, and many features visible today may have been formed then. The drainage history of the Pecos River is related to extensive karstification of the Pecos Valley during mid-Pleistocene time. Large-scale stream piracy and dissolution of salt in the subsurface resulted in major shifts and excavations in the channel. In spite of intensive groundwater studies that have been carried out in the region, major problems in near-surface evaporite karst remain to be solved. Among these are determination of recharge areas and time of recharge. 109 refs., 31 figs., 1 tab.

  11. Migration behavior of pronghorn in southeastern Idaho

    SciTech Connect

    Hoskinson, R.L.; Tester, J.R.

    1980-01-01

    Fifty-four pronghorn (Antilocapra americana) were radio-collared out of 232 captured on 3 winter ranges in southeastern Idaho. Radioed pronghorn were followed for up to 21 months each, from December 1975 through August 1977. Winter home ranges showed a difference (P < 0.005) in size among valleys the 1st winter and were different in size and location within valleys between years. Snow covered the ground 1 week earlier and lasted 3 weeks longer in 1975 to 1976 than in 1976 to 1977. Spring migration began more than 1 month earlier in 1977 than 1976, and appeared related to loss of snow cover on the winter ranges in both years. Distances that pronghorn migrated in spring 1976 were different among valleys (P < 0.05) but directions were, in general, upward to areas near the heads of the valleys. Summer home ranges of all radioed pronghorn averaged 2033 +- 322 (SE) ha. Yearlings wandered during summer and their home ranges were 2 to 5 times as large as ranges of adults. Fall migration in 1976 began after 1 October and was not prompted by snowfall. Percent moisture in vegetation is suggested as a stimulus for onset of fall migration, and snowfall is suggested as a factor influencing distance migrated and location of winter.

  12. Dengue virus in bats from southeastern Mexico.

    PubMed

    Sotomayor-Bonilla, Jesús; Chaves, Andrea; Rico-Chávez, Oscar; Rostal, Melinda K; Ojeda-Flores, Rafael; Salas-Rojas, Mónica; Aguilar-Setien, Álvaro; Ibáñez-Bernal, Sergio; Barbachano-Guerrero, Arturo; Gutiérrez-Espeleta, Gustavo; Aguilar-Faisal, J Leopoldo; Aguirre, A Alonso; Daszak, Peter; Suzán, Gerardo

    2014-07-01

    To identify the relationship between landscape use and dengue virus (DENV) occurrence in bats, we investigated the presence of DENV from anthropogenically changed and unaltered landscapes in two Biosphere Reserves: Calakmul (Campeche) and Montes Azules (Chiapas) in southern Mexico. Spleen samples of 146 bats, belonging to 16 species, were tested for four DENV serotypes with standard reverse transcriptase polymerase chain reaction (RT-PCR) protocols. Six bats (4.1%) tested positive for DENV-2: four bats in Calakmul (two Glossophaga soricina, one Artibeus jamaicensis, and one A. lituratus) and two bats in Montes Azules (both A. lituratus). No effect of anthropogenic disturbance on the occurrence of DENV was detected; however, all three RT-PCR-positive bat species are considered abundant species in the Neotropics and well-adapted to disturbed habitats. To our knowledge, this study is the first study conducted in southeastern Mexico to identify DENV-2 in bats by a widely accepted RT-PCR protocol. The role that bats play on DENV's ecology remains undetermined. PMID:24752688

  13. Effect of grid size in RCMs on the representation of floods in small and medium sized catchments in Austria: added value of convection-permitting simulations

    NASA Astrophysics Data System (ADS)

    Reszler, Christian; Truhetz, Heimo; Switanek, Matthew

    2016-04-01

    This paper presents a small multi-model ensemble study of coupling two different ERA-Interim driven RCMs (WRF and COSMO-CLM) using different grid sizes (0.44°, 0.11°, 0.03°) with a hydrological model for representing floods in small to medium sized catchments in South-eastern Austria. The aim is to evaluate the benefit of grid size reduction and in particular, the added value of convection-permitting simulations with 0.03° (~ 3 km) resolution. The hydrological model is a spatially distributed model (1 km² grid), which was previously developed for operational flood forecasting and calibrated against data of more than 20 stream gauges with corresponding catchment sizes between 30 and 1000 km². The hindcast simulations (1989-2010) are evaluated in terms of accurately representing flood frequency, seasonality, as well as other flood event characteristics, such as weather type, antecedent soil moisture, etc. The results show, that for small catchments (< 200 km²) a resolution of 3 km is essential to accurately simulate the magnitude of flood events. Flood frequency and seasonality is represented well in all catchments. In the larger catchments a resolution of 0.11° (~ 12.5 km) already yields statistically satisfying results. Also, due to the short response times in the small sub-catchments a time step of 1 hour is required. However, in all setups a bias still exists in precipitation and temperature, which sometimes leads to unrealistic hydrological conditions. Ongoing work comprises the test a of novel statistical error correction method, which is expected to improve results particularly for higher quantiles. Also, a future run ("time-slice" experiment) is planned with the coupled model setup using the RCP8.5 emission scenario, the GCM of the Max-Planck-Institute Hamburg (MPI-ESM-LR), dynamically downscaled to 3 km by COSMO-CLM, and the novel error correction method. The study is funded by the Austrian Klima- und Energiefonds through the Austrian Climate

  14. Hydrologic responses of a tropical catchment in Thailand and two temperate/cold catchments in north America to global warming

    SciTech Connect

    Gan, T.Y.; Ahmad, Z.

    1997-12-31

    The hydrologic impact or sensitivities of three medium-sized catchments to global warming, one of tropical climate in Northern Thailand and two of temperate climate in the Sacramento and San Joaquin River basins of California, were investigated.

  15. Geostatistical prediction of stream-flow regime in southeastern United States

    NASA Astrophysics Data System (ADS)

    Pugliese, Alessio; Castellarin, Attilio; Archfield, Stacey; Farmer, William

    2015-04-01

    A Flow-Duration Curve (FDC) represents the percentage of time (duration) during which a given stream-flow is equalled or exceeded over a given period of time. In many water-engineering applications FDCs need to be predicted for ungauged sites (Prediction in Ungauged Basins, PUB problem) using the information collected in donor neighboring gauged basins. We present an application of kriging procedures which makes the procedures capable of predicting FDCs in ungauged catchments. As many of the techniques proposed in the recent literature, the curve is predicted at the target site as a weighted average of empirical dimensionless FDCs that are constructed for neighboring streamgauges and standardized by discharge Q*. Geostatistical weights are obtained by applying two different interpolation techniques, i.e. Top-kriging (TK, see e.g. Pugliese et al., 2014) and Ordinary-kriging (OK, see e.g. Castiglioni et al., 2009), for interpolating a point streamflow-index computed as the overall negative deviation of each empirical curve from Q*, which we term Total Negative Deviation (TND). Empirical TND values can be used to assess the hydrological similarity between catchments and can be interpolated using TK or OK procedures along the stream-network. We consider period-of-record/annual, and complete/seasonal FDCs standardized by two different Q* values, i.e. Mean Annual Flow (MAF) and Mean Annual Precipitation at catchment scale times the drainage area (MAP*), and we apply TK and OK in a wide study area in the Southeastern United States including 182 unregulated gauged catchments. The accuracy of the predicted FDCs is assessed comprehensively under different operational conditions through the (1) leave-one-out and (2) three-fold cross-validation procedures. The results are compared with six different methods for predicting FDCs from synthetically generated daily stream-flow series, which were recently analysed by U.S. Geological Survey. The application of OK and TK reveal

  16. Dechlorane-related compounds in franciscana dolphin (Pontoporia blainvillei) from southeastern and southern coast of Brazil.

    PubMed

    de la Torre, A; Alonso, M B; Martínez, M A; Sanz, P; Shen, L; Reiner, E J; Lailson-Brito, J; Torres, J P M; Bertozzi, C; Marigo, J; Barbosa, L; Cremer, M; Secchi, E; Malm, O; Eljarrat, E; Barceló, D

    2012-11-20

    Concentrations of Dechlorane (Dec) 603 (0.75 ng/g lipid weight (lw); mean) and Dec 602 (0.38 ng/g lw; mean) were quantified in more than 95% of the franciscana (Pontoporia blainvillei) dolphin samples, whereas the frequency of detection decreased to 75% for Dechlorane Plus (DP) (1.53 ng/g lw, mean). The presence of Chlordene Plus (CP) was also observed (0.13 ng/g lw, mean) in half of the samples. On the contrary, Dec 604, decachloropentacyclooctadecadiene (aCl(10)DP), and undecachloropentacyclooctadecadiene (aCl(11)DP) concentrations were below the limit of quantifications in all cases. To the best of our knowledge, this is the first article reporting the presence of Dec 603, Dec 602, and CP in mammals. For comparative purposes, levels of Mirex, polybrominated diphenyl ethers (PBDEs), and decabromodiphenylethane (DBDPE) are also reported. Considering geographic distribution evaluation together with the strong positive correlations found between DP and PBDEs (r(s) = 0.63; p < 0.01), highly anthropogenic areas were identified as potential sources of these chemicals in this dolphin species. However, local sources for Dec 602, 603, Mirex, CP, and DBDPE were not found indicating that in this case historical use and/or atmospheric transport and deposition may play an important role in their fate. PMID:23016984

  17. Biomass burning aerosol in the State of São Paulo (Southeastern Brazil)

    NASA Astrophysics Data System (ADS)

    Lara, L. L. S.; Artaxo, P.; Martinelli, L. A.; Camargo, P. B.; Ferraz, E. S. B.

    2003-04-01

    A detailed aerosol source apportionment study has been performed in three sites in State of São Paulo with different land-use: sugarcane crops, cattle, urban area and forest. During the summer and winter, the period when sugarcane is burned every year, PM10 has been sampled during day and night in a period of 48 hours, using stacked filters units collecting fine and coarse particulate mode, providing mass, BC and elemental concentration for each aerosol mode. The concentrations of around 20 elements were determined using particle induced X-ray emission technique (PIXE). Ion chromatography was used to determine up to 11 water-soluble ion components. Highest levels of pollutants have been measured around the sugarcane crops, where the annual PM10 concentration (57.1"45.2µgm-3) exceeds of the other urban and industrialized areas and the BC concentration is significantly higher during the sugarcane burning period (4.2"2.2 µgm-3) than the rest of the year (2.0"1.0 µgm-3). The main sources of the aerosol are correlated to the land cover. Factor and cluster analysis showed the main source int the State of São Paulo is biomass burning, followed by soil dust, biogenic emissions and industrial emissions. The sampling and analytical procedures applied in this study showed the sugarcane burning and agricultural practices are the main source of inhalable particulate, possibly altering the aerosol concentration in some places of the State of São Paulo.

  18. Four new species of Polycirrus Grube, 1850 (Polychaeta: Terebellidae) from Campos Basin, southeastern Brazil.

    PubMed

    Carrerette, Orlemir; Nogueira, João Miguel De Matos

    2013-01-01

    Four new species of Polycirrus were collected at the Campos Basin, state of Rio de Janeiro, during a survey coordinated by CENPES/PETROBRAS under the scope of the project, "Environmental Heterogeneity in the Campos Basin". These species are P. nonatoi sp. nov., P. papillosus sp. nov., P. breviuncinatus sp. nov., and P. habitats sp. nov. All these species are herein described and compared with the morphologically most similar congeners. In addition, a key is provided for the identification of the species of Polycirrus which have been originally described for the Brazilian coast. PMID:26176130

  19. Water Use Efficiency under Different Tillage and Irrigation Systems for Tomato Farming in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Bhering, S. B.; Fernandes, N. F.; Macedo, J. R.

    2009-04-01

    In the northwest part of Rio de Janeiro state water availability is one of the main limiting factors for human development and crop productivity. In the same way that shortage of freshwater is one of the main problems, the tomato production systems waste water and highly degrade the environment. The search for the water use efficiency is a challenge in tomato sustainable development production systems. This study aimed to contribute towards the development of sustainable production systems for the tomato farming in the northwestern part or Rio de Janeiro state, as well as increase water use efficiency and the improvement of our understanding on the role played by soil and water management practices on soil hydrology, especially on the amount of water available for the plants. The study was carried out at an experimental watershed in the city of São José do Ubá, in the northwestern portion of Rio de Janeiro state. This city has one of the worst human development index (HDI = 0718) of the state, occupying one of the last 6 positions (85 in 91), with serious problems of education, sanitation, water supply and public health. This area is characterized by an extensive steep hilly topography constituted by long convex-concave hillslopes separated by flat valley-bottoms. The original Atlantic Forest was continuously removed for the introduction of farming and grazing activities, which currently dominate the landscape of the region. The combination of such topographic and land-use characteristics tend to generate a variety of erosional processes, including rill and interrill erosion, gullies and even landslides. The average annual rainfall in the area is about 1,171 mm, with most of rain concentrated during the summer season, making December the wetter and July the drier months. The water balance is negative for most of the year, with the exception of the period from November to January. The cultivation in the area is traditionally done using production systems that highly degrade the environment, applied without practices of soil and water conservation. Such production systems are associated with a variety of environmental problems, such as soil erosion, the extensive pumping of groundwater, the partial obstruction of surface drainage to form artificial lakes, the contamination of groundwater, among others. The environmental impacts generated by all these problems assume a greater importance due to the complete absence of monitoring the continuous lowering of the water table and the changes in water quality. We consider that the main management strategies for developing sustainable production systems for the tomato farming in this area should be based on monitoring water use efficiency, increasing water availability in the root zone and also preventing runoff, leaching and evaporation of water from the soil. Therefore, techniques were applied as green manures with legumes without incorporation of the biomass, non-mechanized and curve-level soil preparation, planting in level, soil cover with crop residues, fertirrigation with solid fertilization of low value, the conduct of tomato especially supported by plastic string attached to a trellis, drip irrigation, and monitoring soil water potential (SWP) with Watermak sensors. At the end of the tomato cycle, water use efficiency and the productivity were compared at 8 micro-plots installed in the 3 studied production systems: conventional tillage (CT-H), minimum tillage (MT-H), both with "wetting irrigation with garden hose", and no-tillage with drip irrigation (NT-D). For each production system, soil physical properties were characterized and soil water potential (SWP) and soil temperature were continuously monitored at different depths (20, 40, 60 and 80 cm), as well as the total water volume used in each irrigation. In parallel, we also compared the development of the root system and the final productivity for each one of the three production systems. The results obtained in this study did no suggest significant modifications on soil physical properties among the thr

  20. Differential Diptera succession patterns onto partially burned and unburned pig carrion in southeastern Brazil.

    PubMed

    Oliveira-Costa, J; Lamego, C M D; Couri, M S; Mello-Patiu, C A

    2014-11-01

    In the present contribution we compared the entomological succession pattern of a burned carcass with that of an unburned one. For that, we used domestic pig carcasses and focused on Calliphoridae, Muscidae and Sarcophagidae flies, because they are the ones most commonly used in Postmortem Interval estimates. Adult and immature flies were collected daily. A total of 27 species and 2,498 specimens were collected, 1,295 specimens of 26 species from the partially burned carcass and 1,203 specimens of 22 species from the control carcass (unburned). The species composition in the two samples differed, and the results of the similarity measures were 0.875 by Sorensen and 0.756 by Bray-Curtis index. The results obtained for both carcasses also differ with respect to the decomposition process, indicating that the post mortem interval would be underestimated if the entomological succession pattern observed for a carcass under normal conditions was applied to a carbonized carcass. PMID:25627597

  1. Hospitalizations for ambulatory care-sensitive conditions, Minas Gerais, Southeastern Brazil, 2000 and 2010

    PubMed Central

    Rodrigues-Bastos, Rita Maria; Campos, Estela Márcia Saraiva; Ribeiro, Luiz Cláudio; Bastos, Mauro Gomes; Bustamante-Teixeira, Maria Teresa

    2014-01-01

    OBJECTIVE To analyze hospitalization rates and the proportion of deaths due to ambulatory care-sensitive hospitalizations and to characterize them according to coverage by the Family Health Strategy, a primary health care guidance program. METHODS An ecological study comprising 853 municipalities in the state of Minas Gerais, under the purview of 28 regional health care units, was conducted. We used data from the Hospital Information System of the Brazilian Unified Health System. Ambulatory care-sensitive hospitalizations in 2000 and 2010 were compared. Population data were obtained from the demographic censuses. RESULTS The number of ambulatory care-sensitive hospitalizations declined from 20.75/1,000 inhabitants [standard deviation (SD) = 10.42) in 2000 to 14.92/thousand inhabitants (SD = 10.04) in 2010 Heart failure was the most frequent cause in both years. Hospitalizations rates for hypertension, asthma, and diabetes mellitus, decreased, whereas those for angina pectoris, prenatal and birth disorders, kidney and urinary tract infections, and other acute infections increased. Hospitalization durations and the proportion of deaths due to ambulatory care-sensitive hospitalizations increased significantly. CONCLUSIONS Mean hospitalization rates for sensitive conditions were significantly lower in 2010 than in 2000, but no correlation was found with regard to the expansion of the population coverage of the Family Health Strategy. Hospitalization rates and proportion of deaths were different between the various health care regions in the years evaluated, indicating a need to prioritize the primary health care with high efficiency and quality. PMID:26039399

  2. Underwater turning movement during foraging in Hydromedusa maximiliani (Testudines, Chelidae) from southeastern Brazil.

    PubMed

    Rocha-Barbosa, O; Hohl, L S L; Novelli, I A; Sousa, B M; Gomides, S C; Loguercio, M F C

    2014-11-01

    A type of locomotor behavior observed in animals with rigid bodies, that can be found in many animals with exoskeletons, shells, or other forms of body armor, to change direction, is the turning behavior. Aquatic floated-turning behavior among rigid bodies animals have been studied in whirligig beetles, boxfish, and more recently in freshwater turtle, Chrysemys picta. In the laboratory we observed a different kind of turning movement that consists in an underwater turning movement during foraging, wherein the animal pivoted its body, using one of the hindlimbs as the fixed-point support in the substratum. We describe, analyze and quantify this movement during foraging in Hydromedusa maximiliani, using observations made in the laboratory. We studied 3 adult specimens (2 males, 1 female) and 2 non-sexed juveniles of H. maximiliani. They were kept individually in an aquarium filled with water and small fish. They were filmed, in dorsal view, at 30 frames per second. Sequences were analyzed frame by frame and points were marked on limbs and shell to enable analysis of variation in limb flexion and extension, as well as rotation movements. While foraging, turtles frequently turned their bodies, using one hind leg as the pivot point. This underwater turning movement, in addition to slow movements with the neck stretched, or staying nearly immobile and scanning the surroundings with lateral movements of the neck (in arcs up to 180°), and fast attacks of neck, may increase prey capture rates. PMID:25627611

  3. Influence of sugar cane burning on aerosol soluble ion composition in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Allen, A. G.; Cardoso, A. A.; da Rocha, G. O.

    2004-09-01

    Seasonal variability in the major soluble ion composition of atmospheric particulate matter in the principal sugar cane growing region of central São Paulo State indicates that pre-harvest burning of sugar cane plants is an important influence on the regional scale aerosol chemistry. Samples of particulate matter were collected between April 1999 and February 2001 in coarse (> 3.5 μm) and fine (< 3.5 μm) fractions, and analysed for HCOO-, CH3COO-, C2O42- , SO42-, NO3-, Cl-, Na+, K+, NH4+, Mg2+ and Ca2+. Results indicated that the principal sources of the aerosols investigated were local or regional in nature (scale of tens to a few hundreds of km), and that differences between air masses of varying origins were small. Fine particles were typically acidic, containing secondary nitrates, sulphates and organic species. Coarse fraction concentrations were mainly influenced by physical parameters (wind speed, movement of vehicles and surface condition) affecting rates of re-suspension, although secondary nitrate and sulphate were also present in the larger particles. Concentrations of all measured species except sodium and chloride were higher during the burning season. Although concentrations were lower than often found in polluted urban environments, the massive increases during much of the year, due to a single anthropogenic activity (sugar cane burning) are indicative of a very large perturbation of the lower troposphere in the region relative to the natural condition. These aerosols are suspected of promoting respiratory disease. They also represent an important mechanism for the tropospheric transport of species relevant to surface acidification (sulphates, nitrates, ammonium and organic acids) and soil nutrient status (potassium, nitrogen, ammonium, calcium), so their impact on fragile natural ecosystems (following deposition) needs to be considered.

  4. Thermal biology of the toad Rhinella schneideri in a seminatural environment in southeastern Brazil

    PubMed Central

    Noronha-de-Souza, Carolina R; Bovo, Rafael P; Gargaglioni, Luciane H; Andrade, Denis V; Bícego, Kênia C

    2015-01-01

    The toad, Rhinella schneideri, is a large-bodied anuran amphibian with a broad distribution over South America. R. schneideri is known to be active at night during the warm/rainy months and goes into estivation during the dry/cold months; however, there is no data on the range of body temperatures (Tb) experienced by this toad in the field, and how environmental factors, thermoregulatory behaviors or activity influence them. By using implantable temperature dataloggers, we provide an examination of Tb variation during an entire year under a seminatural setting (emulating its natural habitat) monitored with thermosensors. We also used data on preferred Tb, allowing us to express the effectiveness of thermoregulation quantitatively. Paralleling its cycle of activity, R. schneideri exhibited differences in its daily and seasonal profile of Tb variation. During the active season, toads spent daytime hours in shelters and, therefore, did not explore microhabitats with higher thermal quality, such as open areas in the sun. At nighttime, the thermal suitability of microhabitats shifted as exposed microhabitats experienced greater temperature drops than the more insulated shelter. As toads became active at night, they were driven to the more exposed areas and, as a result, thermoregulatory effectiveness decreased. Our results, therefore, indicate that, during the active season, a compromise between thermoregulation and nocturnal activity may be at play. During the estivation period, R. schneideri spent the entire day cycle inside the shelter. As toads did not engage in nocturnal activity in those areas with low thermal quality, the overall effectiveness of thermoregulation was, indeed, elevated. In conclusion, we showed that daily and seasonal variation in Tb of an anuran species is highly associated with their respective pattern of activity and may involve important physiological and ecological compromises. PMID:27227075

  5. Spatial distribution and enrichment assessment of heavy metals in surface sediments from Baixada Santista, Southeastern Brazil.

    PubMed

    Kim, Bianca Sung Mi; Salaroli, Alexandre Barbosa; Ferreira, Paulo Alves de Lima; Sartoretto, Juliê Rosemberg; de Mahiques, Michel Michaelovich; Figueira, Rubens Cesar Lopes

    2016-02-15

    The Baixada Santista, besides being an important estuarine system, is responsible for most of the international trade and economic development in the region because of the Santos Port and the Cubatão Industrial Complex. The aim of this study is to assess heavy metal contamination of the Santos São Vicente Estuary using enrichment factors (EFs) and sediment quality guidelines (SQGs). Thus, superficial sediment samples were subjected to acid digestion and analyzed (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sc, V, and Zn) by inductively coupled plasma optical emission spectrometry (ICP-OES). The results indicated an absence of contamination, with the EFs indicating moderate enrichment. As and Pb presented higher enrichment probably due to the natural processes of weathering and sedimentation, and the influence of human activity. This conjoint analysis showed that potentially polluting activities are of concern as the highest values converge near the Cubatão Industrial Complex, which correspond to intense urbanization and industrial activity. PMID:26774439

  6. Distribution of oligochaetes in a stream in the Atlantic Forest in southeastern Brazil.

    PubMed

    Rosa, B F J V; Martins, R T; Alves, R G

    2015-01-01

    The oligochaetes are considered good indicators of ecological conditions and specific types of habitats. Among the factors that influence the distribution of these invertebrates are the water flow and the nature of the substrate. The aim of this study is to describe the composition and distribution of oligochaete species in a first-order stream in Atlantic Forest and try to identify if some species are associated with characteristics of particular types of habitats. In the dry season and in the rainy season, sand and litter samples in two riffle areas and two pool areas were collected in different parts along the stream using a hand net. The greatest observed richness and abundance occurred in sand in the pool, however the greatest estimated richness was obtained for litter in the pool. The Kruskal-Wallis analysis showed effect of the different types of habitat on the abundance and richness of oligochaetes. The Nonmetric Multidimensional Scaling (NMDS) and Multiresponse Permutation Procedure analysis (MRPP) indicated that the variation in the fauna composition had relation with different types of substrates. The indicator species analysis showed that Limnodrilus. hoffmeisteri was an indicator species in both the riffle sand and pool sand and Pristina americana was only an indicator in the pool sand. The high organic matter content in both sandy habitats probably favored the greater abundance of oligochaetes. The results showed that the substrate constitutes an important factor for the local distribution of these invertebrates in streams. The variation of the community structure among mesohabitats and the presence of indicator species of specific types of habitats in the stream demonstrate the importance of environmental heterogeneity for the oligochaetes fauna in forested streams. PMID:25945614

  7. The assemblage composition and structure of swimming crabs (Portunoidea) in continental shelf waters of southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Andrade, L. S.; Frameschi, I. F.; Costa, R. C.; Castilho, A. L.; Fransozo, A.

    2015-02-01

    Three regions along the Brazilian coast characterized by the occurrence of contrasting natural phenomena, such as upwellings and continental input, were surveyed to determine the composition and structure of the assemblage of swimming crabs. Twelve monthly collections were undertaken (July 2010 to June 2011) in Macaé, Rio de Janeiro (MAC); Ubatuba, São Paulo (UBA); and São Francisco do Sul, Santa Catarina (SFS). The lowest values ​​of the phi sediment grain size measure, bottom temperature and the highest values of organic matter and salinity were measured in MAC. In all, 10,686 individuals were collected, belonging to six species of Portunoidea: Arenaeus cribrarius, Callinectes danae, Callinectes ornatus, Callinectes sapidus, Achelous spinicarpus and Achelous spinimanus. A Multiple Response Permutation Procedure (MRPP) test indicated that the species composition differed significantly among the sampling sites, showing substantial heterogeneity in the composition and abundance of species among regions. The results suggest that C. danae was more abundant in waters with lower salinity and lower organic matter content. In contrast, A. spinimanus is positively correlated with these factors, showing a greater abundance under the opposite conditions. Callinectes ornatus appeared not to show strong selectivity for particular habitat characteristics. We conclude from these findings that areas affected by different phenomena produce changes in the composition and abundance of the assemblage of Portunoidea. Although the strength of eutrophication differs between UBA and MAC, the substantial continental inflow affecting SFS favors the development of species that complete their life cycle in the estuary.

  8. Diagnosis of subclinical mastitis in Santa Inês and Morada Nova sheep in southeastern Brazil.

    PubMed

    Zafalon, Luiz Francisco; Santana, Raul Costa Mascarenhas; Pilon, Lucas Eduardo; Júnior, Guilherme Aparecido Fim

    2016-06-01

    The objective of this study was to evaluate different screening limits for the California mastitis test (CMT) and the somatic cell count (SCC) in previous diagnoses of subclinical mastitis in Santa Inês and Morada Nova ewes, which were reared under the same management conditions. Additionally, cutoff points were defined for SCC in accordance with the sensitivity and specificity of the test. A total of 907 mammary halves were subjected to CMT and SCC. The disease was confirmed by means of microbiological identification. Coagulase-negative staphylococci (CNS) were the microorganisms with highest occurrence. The CMT score of 1+ provided adequate sensitivity and specificity at all periods of lactation investigated. This score showed good agreement with SCC, >400,000 cells mL(-1). Higher cell counts favored higher diagnostic specificity. They can be used when producers have financial difficulties relating to treatment or culling of sheep with subclinical mastitis. However, producers should be warned about the risk of false-negative results in the flock. PMID:26994913

  9. Comparing Background and Recent Erosion Rates in Degraded Areas of Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Fernandes, N.; Bierman, P. R.; Sosa-Gonzalez, V.; Rood, D. H.; Fontes, R. L.; Santos, A. C.; Godoy, J. M.; Bhering, S.

    2014-12-01

    Soil erosion is a major problem in northwestern Rio de Janeiro State where, during the last three centuries, major land-use changes took place, associated with the replacement of the original rainforest by agriculture and grazing. The combination of steep hillslopes, erodible soils, sparse vegetation, natural and human-induced fires, as well as downslope ploughing, led to an increase in surface runoff and surface erosion on soil-mantled hillslopes; together, these actions and responses caused a decline in soil productivity. In order to estimate changes in erosion rates over time, we compared erosion rates measured at different spatial and temporal scales, both background (natural) and short-term (human-induced during last few decades). Background long-term erosion rates were measured using in-situ produced cosmogenic 10Be in the sand fraction quartz of active river channel sediment in four basins in the northwestern portion of Rio de Janeiro State. In these basins, average annual precipitation varies from 1,200 to 1,300 mm, while drainage areas vary from 15 to 7,200 km2. Short-term erosion rates were measured in one of these basins from fallout 210Pb in soil samples collected along a hillslope transect located in an abandoned agriculture field. In this transect, 190 undisturbed soil samples (three replicates) were collected from the surface to 0.50 m depth (5 cm vertical intervals) in six soil pits. 10Be average background, basin-wide, erosion rates in the area are ~ 13 m/My; over the last decades, time-integrated (210Pb) average hillslope erosion rates are around 1450 m/Myr, with maximum values at the steepest portion of convex hillslopes of about 2000 m/Myr. These results suggest that recent hillslope erosion rates are about 2 orders of magnitude above background rates of sediment generation integrated over many millennia. This unsustainable rate of soil loss has severely decreased soil productivity eventually leading to the abandonment of farming activities in areas where soil loss is severe.

  10. Reproductive Modes in Leiothrix (Eriocaulaceae) in South-eastern Brazil: The Role of Microenvironmental Heterogeneity

    PubMed Central

    Coelho, Flávia F.; Capelo, Christina; Ribeiro, Leonardo C.; Figueira, José Eugênio C.

    2008-01-01

    Background and Aims The genus Leiothrix (Eriocaulaceae) is restricted to South America and contains 37 taxa. The genus is most species-rich in the mountains of Minas Gerais, where 25 species occur, 19 of them in the Serra do Cipó. Leiothrix taxa that inhabit different microhabitats exhibit a number of reproductive modes. Rhizomatous taxa produce seeds plentifully; therefore, this group were defined as rhizomatous seed-producing. The pseudoviviparous reproductive mode was divided into canopy-forming and rooted. In the first, ramets remain attached to a parental rosette suspended by scapes, whereas in the second, ramets take root and may or may not remain attached to a parental rosette. In this study, it is proposed that microenvironmental heterogeneity is an important factor generating and maintaining reproductive modes in Leiothrix. Methods Soil analyses and vegetation cover estimates were performed for five Leiothrix taxa occurring in 19 areas along the Serra do Cipó. In these 19 points of the Serra do Cipó, soil data were collected from 27 populations of each species, and vegetation cover data were collected from 20 populations, due to fire that occurred in the region and destroyed most of the vegetation. For each population, three replicates were made. A discriminant function analysis was performed, in an attempt to test the effect of microhabitat features in the differentiation of the reproductive modes. Key Results Discriminant function analyses separated the three groups of reproductive modes based mainly on percentage vegetation cover. The pseudoviviparous canopy-forming group occurs under densely crowded conditions, while the pseudoviviparous rooted and rhizomatous seed-producing groups occur in areas with sparse vegetation cover. However, the group pseudoviviparous rooted occurs in soils constituted of exposed sand, while the rhizomatous seed-producing group occurs, frequently, on mat-forming mosses. Conclusions Microenvironmental heterogeneity, specifically heterogeneity in percentage cover of vegetation, appears to have influenced the generation and maintenance of reproductive modes in Leiothrix. Reproductive variation within Leiothrix taxa occupying different microenvironments results from a response to fine-scale habitat variation. Therefore, it is proposed that ecological speciation is an important process in adaptive radiation in this genus. PMID:17998571

  11. Drought Impacts on Reservoir Storage and Hydro-electricity Production in Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Scanlon, B. R.; Melo, D. D.; Yin, L.; Wendland, E.

    2015-12-01

    Brazilian hydroelectric plants (HP) generate ~85% of the total electricity in the country (138 GW). More than half of the number largest reservoirs are located in the Southeast/Midwest region, where ~50% of the population (~100 million) lives. The 2014 drought raised several questions about the resilience of the water sources when several urban centers, including Brazilian's largest metropolis (São Paulo, 20 million people), had their water supply threatened. Such drought also affected reservoirs of hydroelectric plants. This study assesses how the storage and, thus the electricity generation, in 14 of the largest reservoirs were affected by drought events within the past 20 years. We computed the Standardized Precipitation Index (SPI) to identify rainfall anomalies throughout the analyzed period. To evaluate the impacts on surface water, we assessed the changes in total (surface+ subsurface) runoff and soil moisture from Global Land Data Assimilation System (GLDAS) and in Total Water Storage (TWS) from Gravity Recovery and Climate Experiment (GRACE) satellite data. We evaluated the anomalies and significance of the changes in reservoir storage (RS) and electricity generation. The results show that severe dry years (-1.5 < SPI <-2.0) reduce reservoir storage (RS) by up to ~60% of its total capacity. Both electricity generation and reservoir storage showed strong negative trends between 2011 and 2014. Our results also indicate that within the past 20 years, two major depletions in reservoir storage occurred: 2001 and 2014. However, due to lower soil moisture in 2013 compared to that in 2000, distinct impacts were observed on the reservoirs with much stronger impacts on reservoir storage in 2014 relative to those in 2001. No meaningful changes in runoff were shown by GLDAS during the 2014 drought. The observed depletion in the RS in 2014 was similar to that in the TWS, as shown by GRACE data. In 2014, the electricity production by the HP declined by ~20%. As a result, the electricity generated by such source decreased to ~70% of the total production, compared to 82% and 93% in 2013 and 2012, respectively. This analysis highlights the vulnerability of surface water resources and electricity generation to extreme droughts and underscores the need to develop coping mechanisms to enhance drought resilience in the future.

  12. High-frequency whistles of Guiana dolphins (Sotalia guianensis) in Guanabara Bay, southeastern Brazil.

    PubMed

    Andrade, Luciana Guimarães de; Maria Seabra Lima, Isabela; Bittencourt, Lis; Lemos Bisi, Tatiana; Lailson Brito Júnior, José; de Freitas Azevedo, Alexandre

    2015-01-01

    Guiana dolphins produce whistles with a higher frequency and less complexity than most other delphinid species. The present study used a recording system with sampling rate of 192 kHz to describe the high-frequency whistles of Sotalia guianensis in Guanabara Bay, Rio de Janeiro. Eleven acoustic parameters (start, end, minimum, maximum, delta, center and peak frequency, duration, and frequency at 14, 12, and 34 of duration) were measured for all whistles. Whistles with a fundamental frequency up to 66.7 kHz were reported, thereby expanding the known frequency range of this species. PMID:25618093

  13. Changes in plant community of Seasonally Semideciduous Forest after invasion by Schizolobium parahyba at southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Abreu, Rodolfo Cesar Real de; Santos, Francisco Ferreira de Miranda; Durigan, Giselda

    2014-01-01

    The recognition of a species as invasive is generally accepted when it comes from another continent or even from another country, but requires strong evidences of negative impacts to support control actions when the invasive species comes from another region in the same country. Schyzolobium parahyba - the 'guapuruvu', is a Brazilian tree native from the evergreen type of the Atlantic Forest, which has been recorded as invader in a number of remnants of the Seasonally Semideciduous Forest - SSF. We hypothesized that this giant and fast growing invasive tree changes the structure and composition of the understory, thus impairing the forest dynamics. We assessed the invasive population in the whole fragment, and, within the portion invaded, we sampled the regenerating plant community 1) under the largest alien trees, 2) under a native species with similar ecology (Peltophorum dubium), and 3) randomly in the forest. Density, basal area and richness under S. parahyba were remarkably lower than under the equivalent native species or in the understory as a whole. Floristic composition of the plant community was also distinct under S. parahyba, possibly due to increased competition for soil water. Even though the alien species has occupied, as yet, a small proportion of the forest fragment, it dominates the overstory and threatens the regeneration processes under its canopy. In view of our findings, we recommend extirpation of the species from SSF, as well as avoiding cultivation of the species away from its native range.

  14. Coagulase gene typing of Staphylococcus aureus isolated from cows with mastitis in southeastern Brazil

    PubMed Central

    2005-01-01

    Abstract A typing procedure based on polymorphism of the coagulase gene (coa) was used to discriminate Staphylococcus aureus isolated from Minas Gerais dairy cows with mastitis. Amplification of the gene from the 64 S. aureus isolates produced 27 different polymerase chain reaction (PCR) products; 60 isolates showed only 1 amplicon, and 4 showed 2 amplicons. The isolates were grouped into 49 types by analyzing the restriction fragment length polymorphism (RFLP) of the coa gene; the 10 most common types accounted for 39% of the isolates. The results demonstrate that many variants of the coa gene are present in the studied region, although only a few predominate. PMID:16479723

  15. (210)Polonium and (210)lead content of marine birds from Southeastern Brazil.

    PubMed

    Godoy, José Marcus; Siciliano, Salvatore; de Carvalho, Zenildo Lara; Tavares, Davi C; de Moura, Jaílson Fulgencio; Godoy, Maria Luiza D P

    2014-09-01

    In this study, we report the (210)Po and (210)Pb concentrations of bone, muscle and liver samples that were obtained from twelve different marine bird species stranded on beaches in the central-north region of Rio de Janeiro State. Both radionuclides were highly concentrated in the liver samples; however, the lowest mean (210)Po/(210)Pb activity ratio (1.3) was observed in bones compared with liver and muscle (16.8 and 13.8, respectively). Among the species that were studied, Fregata magnificens, with a diet based exclusively on fish, had the lowest (210)Pb and (210)Po concentrations and the lowest (210)Po/(210)Pb activity ratio. The (210)Po concentrations in Puffinus spp. liver samples followed a log-normal distribution, with a geometric mean of 300 Bq kg(-1)wet weight. Only two references pertaining to (210)Po in marine birds were found in a Web of Science search of the literature, and each study reported a different concentration value. The values determined in this experiment are consistent with those in one of the previous studies, which also included one of the species studied in this work. No values for (210)Pb in marine birds have been published previously. PMID:24814720

  16. Mapping invasive species and spectral mixture relationships with neotropical woody formations in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Amaral, Cibele H.; Roberts, Dar A.; Almeida, Teodoro I. R.; Souza Filho, Carlos R.

    2015-10-01

    Biological invasion substantially contributes to the increasing extinction rates of native vegetative species. The remote detection and mapping of invasive species is critical for environmental monitoring. This study aims to assess the performance of a Multiple Endmember Spectral Mixture Analysis (MESMA) applied to imaging spectroscopy data for mapping Dendrocalamus sp. (bamboo) and Pinus elliottii L. (slash pine), which are invasive plant species, in a Brazilian neotropical landscape within the tropical Brazilian savanna biome. The work also investigates the spectral mixture between these exotic species and the native woody formations, including woodland savanna, submontane and alluvial seasonal semideciduous forests (SSF). Visible to Shortwave Infrared (VSWIR) imaging spectroscopy data at one-meter spatial resolution were atmospherically corrected and subset into the different spectral ranges (VIS-NIR1: 530-919 nm; and NIR2-SWIR: 1141-2352 nm). The data were further normalized via continuum removal (CR). Multiple endmember selection methods, including Interactive Endmember Selection (IES), Endmember average root mean square error (EAR), Minimum average spectral angle (MASA) and Count-based (CoB) (collectively called EMC), were employed to create endmember libraries for the targeted vegetation classes. The performance of the MESMA was assessed at the pixel and crown scales. Statistically significant differences (α = 0.05) were observed between overall accuracies that were obtained at various spectral ranges. The infrared region (IR) was critical for detecting the vegetation classes using spectral data. The invasive species endmembers exhibited spectral patterns in the IR that were not observed in the native formations. Bamboo was characterized as having a high green vegetation (GV) fraction, lower non-photosynthetic vegetation (NPV) and a low shade fraction, while pine exhibited higher NPV and shade fractions. The invasive species showed a statistically significant larger number of spectra erroneously assigned to the woodland savanna class versus the alluvial and submontane SSF classes. Consequently, the invasive species tended to be overestimated, especially in the woodland savanna. Bamboo was best classified using the VSWIR(CR) data with the EMC endmember selection method (User's accuracy and Producer's accuracy = 98.11% and 72.22%, respectively). Pine was best classified using NIR2-SWIR(CR) data with the IES selected endmembers (97.06% and 62.26%, respectively). The results obtained during the two-endmember modeling were fully translated into the three-endmember unmixed images. The sub-pixel invasive species abundance analysis showed that MESMA performs well when unmixing at the pixel scale and for mapping invasive species fractions in a complex neotropical environment, at pixel and crown scales with 1-m spatial resolution data.

  17. Removal and insertion of pollinia in flowers of Oxypetalum (Asclepiadaceae) in southeastern Brazil.

    PubMed

    Vieira, Milene Faria; Shepherd, George John

    2002-03-01

    Pollinarium removal and pollinium insertion of seven Oxypetalum species (O. alpinum var. alpinum, O. appendiculatum, O. banksii subsp. banksii, O. jacobinae, O. mexiae, O. pachyglossum and O. subriparium) were recorded in Viçosa. Minas Gerais. They presented a tendency of one or two pollinarium removals and one pollinium insertion (single insertion), except O. appendiculatum. In this species, mainly, two pollinia of the same pollinarium were inserted per stigmatic chamber (double insertion), resulting exceptionally in 6-10 inserted pollinia in a flower, an unusual occurrence among the Asclepiadaceae. No association between removal and insertion was found, e.g., O. subriparium and O. banksii subsp. banksii had the highest pollinarium removal (1.78 and 1.45, respectively) and one of the lowest pollinium insertions (0.02 in both species), per flower. Oxypetalum mexiae showed the lowest pollinarium removal and pollinium insertion per flower (0.09 and 0.01, respectively) among the studied species and other Asclepiadaceae. Oxypetalum subriparium, O. banksii subsp. banksii and O. mexiae might be having reproductive limitations. Pollinarium removal and pollinium insertion per flower of the studied species varied from site to site, similarly to what was recorded for other Asclepiadaceae. PMID:12298264

  18. Coastal habitat degradation and green sea turtle diets in Southeastern Brazil.

    USGS Publications Warehouse

    Santos, Robson G.; Martins, Agnaldo Silva; Farias, Julyana da Nobrega; Horta, Antunes Paulo; Pinheiro, Hudson Tercio; Baptistotte, Cecilia; Seminoff, Jeffrey A.; Balazs, George H.; Work, Thierry M.

    2011-01-01

    To show the influence of coastal habitat degradation on the availability of food for green turtles (Chelonia mydas), we assessed the dietary preferences and macroalgae community at a feeding area in a highly urbanized region. The area showed low species richness and was classified as degraded. We examined stomach contents of 15 dead stranded turtles (CCL = 44.0 cm (SD 6.7 cm)). The diet was composed primarily of green algae Ulva spp. (83.6%). In contrast, the macroalgae community was dominated by the green alga Caulerpa mexicana. We found a selection for red algae, seagrass and Ulva spp., and avoidance for C. mexicana and brown alga Dictyopteris delicatula. The low diversity of available food items, possibly a result of environmental degradation, likely contributed to the low dietary diversity. The nutritional implications of this restricted diet are unclear.

  19. Temporal and Spatial Patterns of Preferential Flow Occurrence in the Shale Hills Catchment: From the Hillslope to the Catchment Scales

    NASA Astrophysics Data System (ADS)

    Liu, H.; Lin, H.

    2013-12-01

    Understanding temporal and spatial patterns of preferential flow (PF) occurrence is important in revealing hillslope and catchment hydrologic and biogeochemical processes. Quantitative assessment of the frequency and control of PF occurrence in the field, however, has been limited, especially at the landscape scale of hillslope and catchment. By using 5.5-years' (2007-2012) real-time soil moisture at 10 sites response to 323 precipitation events, we tested the temporal consistency of PF occurrence at the hillslope scale in the forested Shale Hills Catchment; and by using 25 additional sites with at least 1-year data (2011-2012), we evaluated the spatial patterns of PF occurrence across the catchment. To explore the potential effects of PF occurrence on catchment hydrology, wavelet analysis was performed on the recorded time series of hydrological signals (i.e., precipitation, soil moisture, catchment discharge). Considerable temporal consistence was observed in both the frequency and the main controls of PF occurrence at the hillslope scale, which was attributed largely to the statistical stability of precipitation pattern over the monitoring period and the relatively stable subsurface preferential pathways. Preferential flow tended to occur more often in response to intense rainfall events, and favored the conditions at dry hilltop or wet valley floor sites. When upscaling to the entire catchment, topographic control on the PF occurrence was amplified remarkably, leading to the identification of a subsurface PF network in the catchment. Higher frequency of PF occurrence was observed at the valley floor (average 48%), hilltop (average 46%), and swales/hillslopes near the stream (average 40%), while the hillslopes in the eastern part of the catchment were least likely to experience PF (0-20%). No clear relationship, however, was observed between terrain attributes and PF occurrence, because the initiation and persistency of PF in this catchment was controlled

  20. Spatial distribution of top soil water content in an experimental catchment of the Southeast Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil moisture is an important hydrological variable that characterizes the soil water dynamics influencing surface runoff generation and consequently sediment transport. This work aimed to analyze the spatial patterns of surface soil moisture, identify the elements that exert the most influence in t...

  1. Catchment-scale biogeography of riverine bacterioplankton.

    PubMed

    Read, Daniel S; Gweon, Hyun S; Bowes, Michael J; Newbold, Lindsay K; Field, Dawn; Bailey, Mark J; Griffiths, Robert I

    2015-02-01

    Lotic ecosystems such as rivers and streams are unique in that they represent a continuum of both space and time during the transition from headwaters to the river mouth. As microbes have very different controls over their ecology, distribution and dispersion compared with macrobiota, we wished to explore biogeographical patterns within a river catchment and uncover the major drivers structuring bacterioplankton communities. Water samples collected across the River Thames Basin, UK, covering the transition from headwater tributaries to the lower reaches of the main river channel were characterised using 16S rRNA gene pyrosequencing. This approach revealed an ecological succession in the bacterial community composition along the river continuum, moving from a community dominated by Bacteroidetes in the headwaters to Actinobacteria-dominated downstream. Location of the sampling point in the river network (measured as the cumulative water channel distance upstream) was found to be the most predictive spatial feature; inferring that ecological processes pertaining to temporal community succession are of prime importance in driving the assemblages of riverine bacterioplankton communities. A decrease in bacterial activity rates and an increase in the abundance of low nucleic acid bacteria relative to high nucleic acid bacteria were found to correspond with these downstream changes in community structure, suggesting corresponding functional changes. Our findings show that bacterial communities across the Thames basin exhibit an ecological succession along the river continuum, and that this is primarily driven by water residence time rather than the physico-chemical status of the river. PMID:25238398

  2. Catchment-scale biogeography of riverine bacterioplankton

    PubMed Central

    Read, Daniel S; Gweon, Hyun S; Bowes, Michael J; Newbold, Lindsay K; Field, Dawn; Bailey, Mark J; Griffiths, Robert I

    2015-01-01

    Lotic ecosystems such as rivers and streams are unique in that they represent a continuum of both space and time during the transition from headwaters to the river mouth. As microbes have very different controls over their ecology, distribution and dispersion compared with macrobiota, we wished to explore biogeographical patterns within a river catchment and uncover the major drivers structuring bacterioplankton communities. Water samples collected across the River Thames Basin, UK, covering the transition from headwater tributaries to the lower reaches of the main river channel were characterised using 16S rRNA gene pyrosequencing. This approach revealed an ecological succession in the bacterial community composition along the river continuum, moving from a community dominated by Bacteroidetes in the headwaters to Actinobacteria-dominated downstream. Location of the sampling point in the river network (measured as the cumulative water channel distance upstream) was found to be the most predictive spatial feature; inferring that ecological processes pertaining to temporal community succession are of prime importance in driving the assemblages of riverine bacterioplankton communities. A decrease in bacterial activity rates and an increase in the abundance of low nucleic acid bacteria relative to high nucleic acid bacteria were found to correspond with these downstream changes in community structure, suggesting corresponding functional changes. Our findings show that bacterial communities across the Thames basin exhibit an ecological succession along the river continuum, and that this is primarily driven by water residence time rather than the physico-chemical status of the river. PMID:25238398

  3. Quantifying the Chemical Weathering Efficiency of Basaltic Catchments

    NASA Astrophysics Data System (ADS)

    Ibarra, D. E.; Caves, J. K.; Thomas, D.; Chamberlain, C. P.; Maher, K.

    2014-12-01

    The geographic distribution and areal extent of rock type, along with the hydrologic cycle, influence the efficiency of global silicate weathering. Here we define weathering efficiency as the production of HCO3- for a given land surface area. Modern basaltic catchments located on volcanic arcs and continental flood basalts are particularly efficient, as they account for <5% of sub-aerial bedrock but produce ~30% of the modern global weathering flux. Indeed, changes in this weathering efficiency are thought to play an important role in modulating Earth's past climate via changes in the areal extent and paleo-latitude of basaltic catchments (e.g., Deccan and Ethiopian Traps, southeast Asia basaltic terranes). We analyze paired river discharge and solute concentration data for basaltic catchments from both literature studies and the USGS NWIS database to mechanistically understand geographic and climatic influences on weathering efficiency. To quantify the chemical weathering efficiency of modern basalt catchments we use solute production equations and compare the results to global river datasets. The weathering efficiency, quantified via the Damköhler coefficient (Dw [m/yr]), is calculated from fitting concentration-discharge relationships for catchments with paired solute and discharge measurements. Most basalt catchments do not demonstrate 'chemostatic' behavior. The distribution of basalt catchment Dw values (0.194 ± 0.176 (1σ)), derived using SiO2(aq) concentrations, is significantly higher than global river Dw values (mean Dw of 0.036), indicating a greater chemical weathering efficiency. Despite high Dw values and total weathering fluxes per unit area, many basaltic catchments are producing near their predicted weathering flux limit. Thus, weathering fluxes from basaltic catchments are proportionally less responsive to increases in runoff than other lithologies. The results of other solute species (Mg2+ and Ca2+) are comparable, but are influenced both by

  4. Phosphorus delivery via groundwater in agricultural river catchments

    NASA Astrophysics Data System (ADS)

    Mellander, Per-Erik; Jordan, Philip; Shore, Mairead; Melland, Alice R.

    2014-05-01

    Mitigating diffuse phosphorus (P) delivery to rivers, lakes and estuaries in the agricultural landscape is important for ecological quality management. In order to plan this management, it is useful to identify and quantify dominating P transfer pathways and their potential variation over time and space. Phosphorus is anticipated to mainly be transferred to rivers episodically via pathways on the surface and is not usually considered as a major concern in groundwater-fed waters. However, in this paper we report considerable proportions of P delivery via groundwater in two agricultural river catchments with permeable soils. We investigated the P transfer pathways and links between groundwater and surface water, as well as the implication of spatio-temporally variable P concentrations in groundwater at the hillslope scale. We present four years of P concentrations in stream water (sub-hourly) and in groundwater (monthly) of different strata in four hillslopes, as well as estimated P transfer pathways for winter periods (Oct-Jan) in two ca. 10 km2 catchments in Ireland. One catchment was dominated by arable land overlying slate bedrock and the other by grassland overlying sandstone. High temporal resolution monitoring of river discharge and P concentration allowed an estimation of total P (TP) and total reactive P (TRP) transfer pathways as well as flow pathways. In the groundwater of both catchments the 4-year average dissolved reactive P was up to 0.021 mg/l (Arable) and 0.050 mg/l (Grassland) in shallow near-stream groundwater. During the winter periods in the Arable catchment 20% of the runoff, 59% of stream TP load and 35% of stream TRP load was transferred by quick aboveground pathways while 77% of runoff, 36% of TP and 58% of TRP was transferred via delayed groundwater pathways. In the Grassland catchment 10% of the runoff, 48% of TP and 38% of TRP was transferred above ground while 86% of runoff, 46% of TP and 55% of TRP transferred via groundwater. In both

  5. Guiding soil conservation strategy in headwater mediterranean catchments

    NASA Astrophysics Data System (ADS)

    Ben Slimane, Abir; Raclot, Damien; Evrard, Olivier; Sanaa, Mustapha; Lefèvre, Irène; Le Bissonnais, Yves

    2016-04-01

    Reservoir siltation due to water erosion is an important environmental issue in Mediterranean countries where storage of clear surface water is crucial for their economic and agricultural development. In order to reduce water erosion, this study aimed to design a methodology for guiding the implementation of efficient conservation strategies by identifying the dominant sediment sources in Mediterranean context. To this end, a fingerprinting method was combined with long-term field monitoring of catchment sediment yield in five headwater catchments (0.1-10 km2) equipped with a small reservoir between 1990 and 1995. The five catchments were chosen to cover the large diversity of environmental conditions found along the Tunisian Ridge and in the Cape Bon region. The fingerprinting techniques based on measurements of cesium-137 and Total Organic Carbon within the catchments and in reservoir sediment deposits successfully identified the contribution of rill/interrill and gully/channel erosion to sediment yield at the outlet of five small headwater catchments during the last 15-20 years. Results showed the very large variability of erosion processes among the selected catchments, with rill/interrill erosion contributions to sediment accumulated in outlet reservoirs ranging from 20 to 80%. Overall, rill/interrill erosion was the dominant process controlling reservoir siltation in three catchments whereas gully/channel erosion dominated in the other two catchments. This demonstrates that the dominant erosion process in the Mediterranean regions highly depends on the local environmental context. The lowest rill/interrill erosion contribution (2.2 Mg ha-1 yr-1) in the five catchments remained significantly higher than the tolerable soil loss indicating the severe levels reached by soil erosion along the Tunisian Ridge and in the Cape Bon region. This study also showed that although the implementation of improved topsoil management measures greatly reduced rill

  6. Urban influence on litterfall trace metals fluxes in the Atlantic forest of São Paulo (Brazil)

    NASA Astrophysics Data System (ADS)

    Fostier, A.-H.; Cecon, K.; Forti, M. C.

    2003-05-01

    A monitoring project for two forest catchments was establisbed in 2001 in Sâo Paulo State, Brazil. The chosen catchments differed significantly with respect to human occupation. One catchment area, PEFI (23°39'S and 46°37'W), is inside the largest metropolis of South America, the city of São Paulo, within a Park of 549.3 ha, located about 50 km away from the ocean. The other catchment area, CUNHA (between parallels 23°13'18'' and 23°16'10''South and meridians 45°02'53'' and 45°02'53'' West), is within a State Reserve of the Atlantic Forest, with 2850 ha, located about 15 km from the ocean, surrounded by rural areas and small villages. PEFI is about 798 m above sea level, while CUNHA is about 1050 m. In this work we examined the monthly litterfall trace metal (Fe, Mn, Zn, Cu, Cr, Pb, Cr, Cd, Hg) fluxes for both catchments during the 2001 dry season (may to September). Trace element concentrations were also determined in soils. CUNHA is characterized by low fluxes and low concentrations in soil, compared with PEFI. The same tendency was also observed for rainfall and throughfall Fe, Mn, Zn and Cu fluxes.

  7. Niobium (columbium) and tantalum resources of Brazil

    USGS Publications Warehouse

    White, Max Gregg

    1975-01-01

    Most of the niobium resources of Brazil occur as pyrochlore in carbonatites within syenitic intrusives of Late Cretaceous to early Tertiary age in western Minas Gerais and southeastern Goils. Minor amounts of it are produced together with tantalum from columbite-tantalite concentrates from pegmatites and placers adjacent to them, in the Sao Joao del Rei district in south-central Minas Gerais. All the niobium and tantalum produced in Brazil is exported. The only pyrochlore mined is from the Barreiro carbonatite deposit near Araxa in Minas Gerais where concentrates and ferroniobium are produced. Exploration work for pyrochlore and other mineral resources are being undertaken on other carbonatites, particularly at Catalao I in southeast Goias and at Tapira and Serra Negra in western Minas Gerais. Annual production and export from the Barreiro deposit are about 8,000 metric tons of pyrochlore concentrate containing about 60 percent Nb205 and about 2,700 metric tons of ferroniobium with 63 percent Nb2O5. The annual production capacity of the Barreiro plant is 18,000 tons of concentrate and 4,000 tons of ferroniobium. Ore reserves of the Barreiro deposit in all categories are 380 million tons with percent Nb2O5. Annual production of tantalite-columbite from the Sao Joao del Rei district, most of which is exported to the United States, is about 290 tons, of which about 79 percent is tantalite and about percent is columbite. Reserves of tantalite-columbite in the Sao Joao del Rei district are about 43,000 tons of proved and 73,000 tons of probable ore.

  8. Comparison of subsurface connectivity in Alpine headwater catchments

    NASA Astrophysics Data System (ADS)

    Zuecco, Giulia; Rinderer, Michael; van Meerveld, Ilja; Penna, Daniele; Borga, Marco

    2016-04-01

    Saturation at the soil-bedrock interface or the rise of shallow groundwater into more permeable soil layers results in subsurface stormflow and can lead to hillslope-stream connectivity. Despite the importance of subsurface connectivity for streamflow and streamwater chemistry, the factors controlling its spatial and temporal variability are still poorly understood. This study takes advantage of networks of spatially-distributed piezometers in five small (<14 ha) headwater catchments in the Italian Dolomites and the Swiss pre-Alps to i) quantify and compare the spatial and temporal variability of subsurface connectivity and its relation to streamflow, and ii) assess whether the differences in connectivity between the catchments are related to climatological or morphological characteristics of the catchments (e.g. the presence of a riparian zone). Shallow groundwater levels were measured for two years from spring to fall in 16 and 12 piezometers in the 14 and 3.3 ha catchments in the Italian Dolomites, and for four years from spring to fall in 7-8 piezometers in three <1 ha Swiss pre-alpine catchments. Subsurface connectivity was quantified by a graph-theory approach, considering linear connections (edges) between the piezometers (nodes). A node was considered to be connected to the stream when shallow groundwater was observed in the piezometer and it was connected by the edges to the stream. Weights were given to each piezometer based on Thiessen polygons to determine the area of the catchment that was connected to the stream. For the Swiss pre-alpine catchments the duration that nodes were connected to the stream was significantly correlated to the local and upslope site characteristics, such as the topographic wetness index, local slope and curvature. For the dolomitic catchment with the largest riparian zone, the time that nodes were connected to the stream was correlated with downslope site characteristics, such as the vertical distance to the nearest stream

  9. Stormflow generation: A meta-analysis of field evidence from small, forested catchments

    NASA Astrophysics Data System (ADS)

    Barthold, Frauke K.; Woods, Ross A.

    2015-05-01

    Combinations of runoff characteristics are commonly used to represent distinct conceptual models of stormflow generation. In this study, three runoff characteristics: hydrograph response, time source of runoff water, and flow path are used to classify catchments. Published data from the scientific literature are used to provide evidence from small, forested catchments. Each catchment was assigned to one of the eight conceptual models, depending on the combination of quick/slow response, old/new water, and overland/subsurface flow. A standard procedure was developed to objectively diagnose the predominant conceptual model of stormflow generation for each catchment and assess its temporal and spatial support. The literature survey yielded 42 catchments, of which 30 catchments provide a complete set of qualitative runoff characteristics resulting in one of the eight conceptual models. The majority of these catchments classify as subsurface flow path dominated. No catchments were found for conceptual models representing combinations of quick response-new water-subsurface flow (SSF), slow-new-SSF, slow-old-overland flow (OF) nor new-slow-OF. Of the 30 qualitatively classified catchments, 24 provide a complete set of quantitative measures. In summary, the field support is strong for 19 subsurface-dominated catchments and is weak for 5 surface flow path dominated catchments (six catchments had insufficient quantitative data). Two alternative explanations exist for the imbalance of field support between the two flow path classes: (1) the selection of research catchments in past field studies was mainly to explain quick hydrograph response in subsurface dominated catchments; (2) catchments with prevailing subsurface flow paths are more common in nature. We conclude that the selection of research catchments needs to cover a wider variety of environmental conditions which should lead to a broader, and more widely applicable, spectrum of resulting conceptual models and process

  10. Regional Wave Propagation in Southeastern United States

    NASA Astrophysics Data System (ADS)

    Jemberie, A. L.; Langston, C. A.

    2003-12-01

    Broad band seismograms from the April 29, 2003, M4.6 Fort Payne, Alabama earthquake are analyzed to infer mechanisms of crustal wave propagation, crust and upper mantle velocity structure in southeastern United States, and source parameters of the event. In particular, we are interested in producing deterministic models of the distance attenuation of earthquake ground motions through computation of synthetic seismograms. The method first requires constraining the source parameters of an earthquake and then modeling the amplitude and times of broadband arrivals within the waveforms to infer appropriate layered earth models. A first look at seismograms recorded by stations outside the Mississippi Embayment (ME) show clear body phases such P, sP, Pnl, Sn and Lg. The ME signals are qualitatively different from others because they have longer durations and large surface waves. A straightforward interpretation of P wave arrival times shows a typical upper mantle velocity of 8.18 km/s. However, there is evidence of significantly higher P phase velocities at epicentral distances between 400 and 600km, that may be caused by a high velocity upper mantle anomaly; triplication of P-waves is seen in these seismograms. The arrival time differences between regional P and the depth phase sP at different stations are used to constrain the depth of the earthquake. The source depth lies between 9.5 km and 13km which is somewhat more shallow than the network location that was constrained to 15km depth. The Fort Payne earthquake is the largest earthquake to have occurred within the Eastern Tennessee Seismic Zone.

  11. Chinese Tallow: Invading the Southeastern Coastal Plain

    USGS Publications Warehouse

    U.S. Geological Survey

    2000-01-01

    Chinese tallow is an ornamental tree with colorful autumn foliage that can survive full sunlight and shade, flooding, drought, and in some cases fire. To horticulturists this kind of tree sounds like a dream, but to ecologists, land managers, and land owners this kind of tree can be a nightmare, especially when it invades an area and takes over native vegetation. Chinese tallow (Triadica sebifera), a nonnative tree from China, is currently transforming the southeastern Coastal Plain. Over the last 30 years, Chinese tallow has become a common tree in old fields and bottomland swamps of coastal Louisiana. Several studies at the U.S. Geological Survey's National Wetlands Research Center (NWRC), Lafayette, Louisiana, are aimed at understanding the factors that contribute to Chinese tallow growth, spread, and management. When tallow invades, it eventually monopolizes an area, creating a forest without native animal or plant species. This tree exhibits classic traits of most nonnative invaders: it is attractive so people want to distribute it, it has incredible resiliency, it grows quickly and in a variety of soils, and it is resistant to pests. In the coastal prairie of Louisiana and Texas, Chinese tallow can grow up to 30 feet and shade out native sun-loving prairie species. The disappearing of prairie species is troublesome because less than 1% of original coastal prairie remains, and in Louisiana, less than 500 of the original 2.2 million acres still exist. Tallow reproduces and grows quickly and can cause large-scale ecosystem modification (fig. 1). For example, when it completely replaces native vegetation, it has a negative effect on birds by degrading the habitat. Besides shading out grasses that cattle like to eat, it can also be potentially harmful to humans and animals because of its berries (fig. 2) and plant sap that contain toxins. There is some concern its leaves may shed toxins that change the soil chemistry and make it difficult for other plants to grow.

  12. Hydroclimatic changes and drivers in the Sava River Catchment and comparison with Swedish catchments.

    PubMed

    Levi, Lea; Jaramillo, Fernando; Andričević, Roko; Destouni, Georgia

    2015-11-01

    In this study, we investigate long-term hydroclimatic changes and their possible relation to regional changes in climate, land-use and water-use over the twentieth century in the transboundary Sava River Catchment (SRC) in South Eastern Europe. In a hydropower dominated part of the SRC, unlike in an unregulated part, we find increase in average annual evapotranspiration and decrease in temporal runoff variability, which are not readily explainable by observed concurrent climate change in temperature and precipitation and may be more related to landscape-internal change drivers. Among the latter investigated here, results indicate hydropower developments as most closely related to the found hydroclimatic shifts, consistent with previous such indications in studies of Swedish hydropower catchments. Overall, the present results have quantitatively framed the recent history and present state of hydroclimate in the SRC, of relevance for water resources in several countries and for a majority of their populations. This provides a useful basis for further assessment of possible future hydroclimatic changes, under different scenarios of climate change and land/water-use developments in the region. PMID:25753574

  13. A Watershed Directory As A Basis For Integrated River Catchment Management of The Modau Catchment (germany)

    NASA Astrophysics Data System (ADS)

    Klawitter, A.; Ostrowski, M.

    A key element of the EU Water Framework Directive is the River Basin Management Plan providing the program of measures, which are aimed at protecting and meliorat- ing surface waters, groundwaters and other protected areas. A further important role in the River Basin Management Plan plays the monitoring of surface waters, as well as groundwaters and protected areas, which was the trigger for this investigation. The Modau catchment, situated East of the Rhine in South Hesse, is intensively used by agriculture and industry, and is furthermore densely populated. The river channel is severely impaired by urban settlements and water engineering works. Finally, the lower part of the Modau catchment is used for groundwater extraction. Due to these facts, an integrated water management is compulsory. The main purpose of the investigation was to establish a watershed directory com- bining all available information for watershed management and to evaluate this data basis towards its suitability for a River Basin Management Plan. A further purpose was to identify deficits as well as information gaps in this data basis. During the inves- tigation, a preliminary assessment of the monitoring and management strategies was carried out, to see whether current work with regard to river basin management meets the requirements of the Water Framework Directive.

  14. Biotic controls on solute distribution and transport in headwater catchments

    NASA Astrophysics Data System (ADS)

    Herndon, E. M.; Dere, A. L.; Sullivan, P. L.; Norris, D.; Reynolds, B.; Brantley, S. L.

    2015-01-01

    Solute concentrations in stream water vary with discharge in patterns that record complex feedbacks between hydrologic and biogeochemical processes. In a comparison of headwater catchments underlain by shale in Pennsylvania, USA (Shale Hills) and Wales, UK (Plynlimon), dissimilar concentration-discharge behaviors are best explained by contrasting landscape distributions of soil solution chemistry - especially dissolved organic carbon (DOC) - that have been established by patterns of vegetation. Specifically, elements that are concentrated in organic-rich soils due to biotic cycling (Mn, Ca, K) or that form strong complexes with DOC (Fe, Al) are spatially heterogeneous in pore waters because organic matter is heterogeneously distributed across the catchments. These solutes exhibit non-chemostatic "bioactive" behavior in the streams, and solute concentrations either decrease (Shale Hills) or increase (Plynlimon) with increasing discharge. In contrast, solutes that are concentrated in soil minerals and form only weak complexes with DOC (Na, Mg, Si) are spatially homogeneous in pore waters across each catchment. These solutes are chemostatic in that their stream concentrations vary little with stream discharge, likely because these solutes are released quickly from exchange sites in the soils during rainfall events. Differences in the hydrologic connectivity of organic-rich soils to the stream drive differences in concentration behavior between catchments. As such, in catchments where soil organic matter (SOM) is dominantly in lowlands (e.g., Shale Hills), bioactive elements are released to the stream early during rainfall events, whereas in catchments where SOM is dominantly in uplands (e.g., Plynlimon), bioactive elements are released later during rainfall events. The distribution of vegetation and SOM across the landscape is thus a key component for predictive models of solute transport in headwater catchments.

  15. Terrain representation impact on periurban catchment morphological properties

    NASA Astrophysics Data System (ADS)

    Rodriguez, F.; Bocher, E.; Chancibault, K.

    2013-04-01

    SummaryModelling the hydrological behaviour of suburban catchments requires an estimation of environmental features, including land use and hydrographic networks. Suburban areas display a highly heterogeneous composition and encompass many anthropogenic elements that affect water flow paths, such as ditches, sewers, culverts and embankments. The geographical data available, either raster or vector data, may be of various origins and resolutions. Urban databases often offer very detailed data for sewer networks and 3D streets, yet the data covering rural zones may be coarser. This study is intended to highlight the sensitivity of geographical data as well as the data discretisation method used on the essential features of a periurban catchment, i.e. the catchment border and the drainage network. Three methods are implemented for this purpose. The first is the DEM (for digital elevation model) treatment method, which has traditionally been applied in the field of catchment hydrology. The second is based on urban database analysis and focuses on vector data, i.e. polygons and segments. The third method is a TIN (or triangular irregular network), which provides a consistent description of flow directions from an accurate representation of slope. It is assumed herein that the width function is representative of the catchment's hydrological response. The periurban Chézine catchment, located within the Nantes metropolitan area in western France, serves as the case study. The determination of both the main morphological features and the hydrological response of a suburban catchment varies significantly according to the discretization method employed, especially on upstream rural areas. Vector- and TIN-based methods allow representing the higher drainage density of urban areas, and consequently reveal the impact of these areas on the width function, since the DEM method fails. TINs seem to be more appropriate to take streets into account, because it allows a finer

  16. Hydrological drought severity explained by climate and catchment characteristics

    NASA Astrophysics Data System (ADS)

    Van Loon, A. F.; Laaha, G.

    2015-07-01

    Impacts of a drought are generally dependent on the severity of the hydrological drought event, which can be expressed by streamflow drought duration or deficit volume. For prediction and the selection of drought sensitive regions, it is crucial to know how streamflow drought severity relates to climate and catchment characteristics. In this study we investigated controls on drought severity based on a comprehensive Austrian dataset consisting of 44 catchments with long time series of hydrometeorological data (on average around 50 year) and information on a large number of physiographic catchment characteristics. Drought analysis was performed with the variable threshold level method and various statistical tools were applied, i.e. bivariate correlation analysis, heatmaps, linear models based on multiple regression, varying slope models, and automatic stepwise regression. Results indicate that streamflow drought duration is primarily controlled by storage, quantified by the Base Flow Index or by a combination of catchment characteristics related to catchment storage and release, e.g. geology and land use. Additionally, the duration of dry spells in precipitation is important for streamflow drought duration. Hydrological drought deficit, however, is governed by average catchment wetness (represented by mean annual precipitation) and elevation (reflecting seasonal storage in the snow pack and glaciers). Our conclusion is that both drought duration and deficit are governed by a combination of climate and catchment control, but not in a similar way. Besides meteorological forcing, storage is important; storage in soils, aquifers, lakes, etc. influences drought duration and seasonal storage in snow and glaciers influences drought deficit. Consequently, the spatial variation of hydrological drought severity is highly dependent on terrestrial hydrological processes.

  17. Changes in runoff generation due to conversion of catchment vegetation

    NASA Astrophysics Data System (ADS)

    Vilhar, Urša; Kestnar, Klemen; Šraj, Mojca

    2015-04-01

    In Central Europe, many pure Norway spruce stands, established on primary beech sites, were converted into mixed stands over the last 60 years. The conversion of forest management from Norway spruce monocultures into mixed deciduous-coniferous forests changed the forest structure dramatically. This changes could influence the hydrological processes on the catchment scale, associated with changes in runoff generation. In this study, the effect of forest management on the runoff in mixed deciduous-coniferous stands on Pohorje mountains in NE Slovenia were investigated. Two small forested experimental catchments of Oplotnica River on Pohorje were compared with similar size and shape but different share of Norway spruce Picea abies (L. Karst) and European beech Fagus sylvatica (L.). Measured stream flows, throughfall, stemflow and the mixture of forests were compared in the period 2008 till 2013 for both catchments. Hydrological models in the HEC-HMS program were built for both catchmenta, calibrated and validated using measured data. Precipitation losses were estimated by the Soil Conservation Service (SCS) method, while precipitation was converted into surface runoff using the SCS synthetic unit hydrograph procedure. The measured seasonal throughfall and stream flow was lower in the catchment with higher share of spruce in the mixed spruce-beech forest. Modeled precipitation losses in the river basins were 92% and 95% of total precipitation, respectively. The results indicate higher interception, infiltration and accumulation of precipitation in the catchment with higher share of spruce in the mixed spruce-beech forest. Forest management practices should aim towards decreased surface runoff in alpine catchments. Therefore implementation of hydrology-oriented sylvicultural measures via a more accurate prediction of the impacts of tree species conversion on runoff generation in this type of alpine catchments is discussed.

  18. Combining stable isotopes and hydrometric data to investigate the stormflow response of a Mediterranean mountain catchment (Vallcebre Research Catchments, Spain)

    NASA Astrophysics Data System (ADS)

    Latron, Jérôme; Roig-Planasdemunt, Maria; Llorens, Pilar; Gallart, Francesc

    2015-04-01

    The hydrological behaviour of Mediterranean mountain catchments has been investigated in the last two decades in the Vallcebre Research Catchments (NE Spain, 42° 12'N, 1° 49'E) using a twofold approach based on hydrometric measurements and modelling. Results obtained have shown the complexity of the rainfall-runoff relationship as well as the strong non-linearity of the catchment's hydrological response. The hydrological behaviour of the catchments is broadly similar to that observed in more humid regions during wet periods. On the contrary, during dry periods or during wetting up transitions, some runoff generation processes characteristic of humid conditions are temporarily absent, activating a different combination of hydrological processes. Water stable isotopes have been used in the last 3 years for determining the relative contribution of event and pre-event water in the stormflow response, with the aim of improving the understanding of the hydrological behaviour of these catchments. Even if the use of stable isotopes in seasonal Mediterranean catchments has been relatively limited so far compared to humid temperate catchments, results obtained in the Vallcebre Research Catchments showed that the information they provide was very helpful, when used in combination with detailed hydrometric data. Results obtained using stable isotopes were generally in line with previous finding in these catchments, even if the contribution of pre-event water was higher than expected in some conditions. Using a set of 10 stormflow events with different characteristics (antecedent conditions, rainfall depth and intensity, stormflow coefficient), two components hydrograph separations indicated that pre-event water accounted for 30% to almost 100% of the total runoff. The contribution of pre-event water depended more on rainfall characteristics than on antecedent wetness conditions. Moreover, a strong relationship was observed between the new water contribution and the suspended

  19. Debris flows as geomorphic agents in the Huachuca Mountains of southeastern Arizona

    USGS Publications Warehouse

    Wohl, E.E.; Pearthree, P.P.

    1991-01-01

    Numerous debris flows occurred in the Huachuca Mountains of southeastern Arizona during the summer rainy season of 1988 in areas that were burned by a forest fire earlier in the summer. Debris flows occurred following a major forest fire in 1977 as well, suggesting a causal link between fires and debris flows. Abundant evidence of older debris flows preserved along channels and in mountain front fans indicates that debris flows have occurred repeteadly during the late Quaternary in this environment. Soil development in sequences of debris-flow deposits indicates that debris flows probably recur over time intervals of several hundred to a thousand years in individual drainage basins in the study area. Surface runoff in the steep drainage basins of the Huachuca Mountains is greatly enhanced following forest fires, as the hillslopes are denuded of their vegetative cover. Water and sediment eroded from the hillslope regolith are rapidly introduced into the upper reaches of tributary channels by widespread rilling and slope wash during rainfall events. This influx of water and sediment destabilizes regolith previously accumulated in the channel, triggering debris flows that scour the channel to bedrock in the upper reaches. Following a debris flow, the scoured, trapezoidally-shaped channel gradually assumes a swale shape and the percentage of exposed bedrock declines, as material is introduced from the slopes. Debris flows do a tremendous amount of work in a very short time, however, and are the major channel-forming events. Where the tributary channels enter larger, trunk channels, the debris flows serve as the main source of very coarse sediment. The local slope and coarse particle distribution of the trunk channel depend on the competence of water flows in the channel to transport the material introduced by debris flows. Where the smaller channels drain directly to the mountain front, debris flows create extensive alluvial fans which dominate the morphology of the

  20. Catchment systems science and management: from evidence to resilient landscapes

    NASA Astrophysics Data System (ADS)

    Quinn, Paul

    2014-05-01

    There is an urgent need to reassess both the scientific understanding and the policy making approaches taken to manage flooding, water scarcity and pollution in intensively utilised catchments. Many European catchments have been heavily modified and natural systems have largely disappeared. However, working with natural processes must still be at the core of any future manageme