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Avalia??o e espacializa??o da erosividade da chuva no Vale do Rio Doce, regi?o centro-leste do Estado de Minas Gerais
Silva, Mayesse Aparecida da;Silva, Marx Leandro Naves;Curi, Nilton;Santos, Gérson Rodrigues dos;Marques, Jo?o José Granate de Sá e Melo;Menezes, Michele Duarte de;Leite, Fernando Palha;
Revista Brasileira de Ciência do Solo , 2010, DOI: 10.1590/S0100-06832010000400003
Abstract: a very active and influential parameter in the erosive process is the r factor, called rainfall erosivity. this factor is one of the components of the universal soil loss equation. studies in spatial variability have been conducted in an attempt to define the spatial distribution of the r factor for a given region. this study aimed to calculate the rainfall erosivity (r factor - ei30) to generate spatial maps. the study was conducted in experimental areas of eucalyptus stands in nine counties of the rio doce valley, central-eastern region of minas gerais state, brazil. rainfall data from january 2005 to december 2008 were used. erosivity was spatialized according to geostatistical principles and data interpolation using kriging. the annual rainfall erosivity indexes ranged from 7,970 to 18,646 mj mm ha-1 h-1 year -1 . the reaching distance of the monthly erosivity index varied from 10 to 177 km, and was 52 km for the annual index.
Potencial erosivo e características das chuvas de Encruzilhada do Sul, RS Erosivity potential and characteristics of rainfalls at Encruzihada do Sul, RS  [cached]
Flávio L. F. Eltz,Elemar A. Cassol,Pedro B. Pascotini
Revista Brasileira de Engenharia Agrícola e Ambiental , 2011,
Abstract: O objetivo deste trabalho foi determinar a erosividade e algumas características das chuvas de Encruzilhada do Sul, com base no período de 1958 a 1988. Para cada chuva considerada erosiva e com base nos pluviogramas diários, foram digitados a hora e o volume acumulado, sendo os dados processados pelo programa computacional CHUVEROS, que calcula o índice EI30, os totais mensais e anuais, determinando também os padr es hidrológicos das chuvas. O coeficiente de chuvas, o período de retorno e a probabilidade de ocorrência, também foram calculados. O período de janeiro a mar o concentra 38% da erosividade anual, com pico maior em fevereiro (808,5 MJ mm ha-1 h-1), enquanto de julho a setembro concentra o período com menor potencial erosivo (14%). Na média, os padr es avan ado, intermediário e atrasado têm 48, 26 e 26% do número de chuvas erosivas, perfazendo 51, 27 e 22% do volume médio anual e 55, 27 e 18% da erosividade média anual. Para Encruzilhada do Sul o valor do índice de erosividade anual é de 5534,3 MJ mm ha-1 h-1 (Fator "R" da USLE), com período de retorno de 2,3 anos e probabilidade de ocorrência de 40,6%. Verificou-se que o potencial erosivo das chuvas (EI30) n o apresenta correla o significativa com o coeficiente de chuvas. The objective of this work was to determine the rainfall erosivity and some characteristics of erosive rainfalls of Encruzilhada do Sul (RS, Brazil), based on the period of 1958 to 1988. For each erosive rainfall, based on daily rainfall charts, the hour and amounts were digited, and processed by the software Chuveros, which calculates the EI30 index, the monthly and annual totals, besides to determine the hydrological pattern of each rainfall. The rainfall coefficient, the return period and its occurrence probability were also calculated. The January to March period concentrates 38% of annual erosivity, with highest peak in February (808.5 MJ mm ha-1 h-1), while July to September concentrates the smallest erosive potential (14%). In the average, the advanced, intermediary and delayed patterns present 48, 26 and 26% of the number of erosive rainfalls per year, respectively, correponding to 51, 27 and 22%, respectively, of the annual volume of erosive rainfalls and 55, 27 and 18% of the average annual erosivity. For Encruzilhada do Sul, the mean annual rainfall erosivity index is 5534.3 MJ mm ha-1 h-1 ("R" Factor of USLE), with a return period of 2.3 years, and occurrence probability of 40.6%. It has been verified that the rainfall erosive potential (EI30) does not present significant correlation to the rainfall coefficient.
Potencial erosivo da chuva de Cuiabá, MT: distribui??o e correla??o com a precipita??o pluviométrica
Almeida, Cristiana O. S;Amorim, Ricardo S. S;Couto, Eduardo G;Eltz, Flávio L. F;Borges, Laurienne E. C;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2011, DOI: 10.1590/S1415-43662011000200011
Abstract: the objectives of this study were: (a) to determine the erosivity factor (r) for the city of cuiabá, as well as its return period and probability of occurrence, (b) to study the annual distribution, seasonal and monthly index erosivity (ei30), (c) to define the period of return for the indices of annual erosivity and maximum most erosive monthly values, and (d) to correlate the ei30 monthly average with rainfall coefficient and monthly precipitation. a set of 889 erosive individual rains was studied in the period 1972 to 1975, 1977 to 1985 and 1995 to 1999, which were digitized and subsequently analyzed to obtain the ei30. the r factor for the cuiabá city was 8.810 mj mm ha-1 h-1 year-1, classified as high, with probability of 42.92%, being matched or exceeded at least once every 2.33 years. the period from october to april concentrated 87% of total annual erosivity, indicating that it is the period of greatest erosion probability. the potential model showed a better fit between the monthly ei30 with the rainfall coefficient.
Malaria vectors of Timor-Leste
Robert D Cooper, Michael D Edstein, Stephen P Frances, Nigel W Beebe
Malaria Journal , 2010, DOI: 10.1186/1475-2875-9-40
Abstract: The survey was carried out over the period February to June 2001. Standard entomological techniques - human landing collections, larval collections and CO2 baited light traps - were used to collect anophelines from the main geographical regions: coastal plains, inland plains, and highlands. Specimens were processed for identification by morphology and genotyped for the ribosomal DNA ITS2 by restriction analysis and/or DNA sequencing. Phylogenetic relationship of Anopheles sundaicus and Anopheles subpictus individuals was also assessed using DNA sequences from the ITS2 and mitochondrial cytochrome-b. All specimens, other than those from larval surveys, were processed to detect the presence of the Plasmodium parasite circumsporozoite protein by ELISA for vector incrimination.Of 2,030 specimens collected, seven species were identified by morphology: Anopheles barbirostris, Anopheles aconitus, Anopheles annularis, Anopheles maculatus, Anopheles peditaeniatus, An. sundaicus and Anopheles vagus. These were confirmed by molecular analysis with the addition of Anopheles flavirostris and an unidentified species designated here as An. vagus genotype B. This latter species was morphologically similar to An. vagus and An. subpictus and is likely to be the An. subpictus described by other workers for Timor. However, genetically this species showed strong affinities to the An. sundaicus complex. Anopheles vagus was the most common species but was rarely collected coming to bite humans; An. barbirostris and An. vagus genotype B were the two most common species collected in human landing catches and both were found positive for CS protein.The anopheline fauna of Timor-Leste is of Oriental origin with no evidence of elements from the Australian Region. The existence of species complexes will make the use of morphological markers problematic in the country. Using molecular analysis a number of issues regarding the anopheline fauna of Timor-Leste were resolved and nine putative specie
The herpetofauna of Timor-Leste: a first report  [cached]
Hinrich Kaiser,Venancio Lopes Carvalho,Jester Ceballos,Paul Freed
ZooKeys , 2011, DOI: 10.3897/zookeys.109.1439
Abstract: Fieldwork conducted throughout Timor-Leste in September 2004 and July 2009 resulted in a collection or recording of 263 herpetological specimens (100 amphibians, 163 reptiles), comprising at least seven species of frogs and toads, 20 species of lizards, seven species of snakes, two species of turtles, and one species of crocodile. Among the amphibians, the most frequently encountered species were toads (Duttaphrynus melanostictus), rice paddy frogs (genus Fejervarya), and rhacophorid treefrogs (Polypedates cf. leucomystax). All three variants of rice paddy frogs encountered represent undescribed species similar to F. verruculosa from neighboring Wetar Island. Records of F. cancrivora and F. limnocharis for Timor Island are apparently errors based on misidentification. We obtained voucher specimens for a total of 147 lizards and voucher photographs only for four specimens of Varanus timorensis. Aside from geckos frequently associated with human habitations (e.g., Gehyra mutilata, Gekko gecko, Hemidactylus frenatus, H. platyurus), we discovered an as yet undescribed species of bent-toed gecko, genus Cyrtodactylus, in the Same valley. Our specimens of H. platyurus are the first record of this species from Timor-Leste. Commonly encountered skinks included four-fingered skinks (genus Carlia), wedge skinks (genus Sphenomorphus), and night skinks (genus Eremiascincus). Notable among the 15 snakes collected was the frequency of pitvipers (Cryptelytrops insularis), which amounted to over 25% of all snakes. Our specimen of the wolfsnake Lycodon subcinctus is the first record of this species for Timor-Leste. Based on these findings, it appears that the biodiversity of amphibians and reptiles in this remote corner of Wallacea is much greater than previously thought, particularly with respect to scincid lizards. The detail we provide in the species accounts is designed to allow the use of this report as a preliminary field guide to the amphibians and reptiles of Timor-Leste. However, survey work is ongoing.
Flúor em chuva simulada: sintomatologia e efeitos sobre a estrutura foliar e o crescimento de plantas arbóreas  [cached]
SILVA LUZIMAR CAMPOS DA,AZEVEDO ARISTéA ALVES,SILVA ELDO ANT?NIO MONTEIRO DA,OLIVA MARCO ANTONIO
Brazilian Journal of Botany , 2000,
Abstract: Os objetivos deste trabalho foram: caracterizar os efeitos do flúor em espécies arbóreas nativas, nos estádios de plantula e muda; identificar injúrias provocadas pelo flúor na estrutura da lamina foliar da espécie mais sensível; fornecer subsídios para sele o de características a serem utilizadas na bioindica o e contribuir com informa es sobre a resistência ou tolerancia das plantas, visando ao reflorestamento de áreas impactadas pela chuva com flúor. As espécies analisadas foram Gallesia gorazema Moq. (Phytolaccaceae), Genipa americana L. (Rubiaceae), Joannesia princeps Vell. (Euphorbiaceae), Peltophorum dubium (Spreng.) Taub. (Leguminosae, Caesalpinioideae) e Spondias dulcis Forst. f. (Anacardiaceae). Plantulas e mudas dessas espécies, provenientes do Parque Estadual do Rio Doce (MG), foram submetidas a 20 min diários de chuva com flúor (30 mg.L-1), por 10 dias consecutivos. Necroses apicais e marginais foram observadas em todas as espécies analisadas, logo após a primeira chuva simulada. S. dulcis, no estádio de muda, foi a espécie mais sensível ao flúor, pois apresentou extensas necroses com apenas dois dias de tratamento, enquanto que G. americana foi a espécie mais resistente. Nas mudas, as espécies que acumularam mais flúor foram também as que apresentaram maior sensibilidade a esse poluente; essa rela o n o foi verificada nas plantulas. A concentra o de flúor utilizada promoveu altera es drásticas na lamina foliar de S. dulcis com extensas áreas necrosadas, danificando toda a sua estrutura anat mica. A sensibilidade ao flúor observada em S. dulcis indica que essa espécie apresenta potencial para ser usada como bioindicadora. Entretanto, estudos detalhados ser o necessários para a melhor caracteriza o das respostas de S. dulcis ao flúor visando a sua utiliza o em programas de biomonitoramento ambiental.
IDP camp closure and gender inequality in Timor-Leste
Phyllis Ferguson
Forced Migration Review , 2010,
Abstract: The goal of humanitarian assistance in Timor-Leste during a seriesof crises from 2006 to 2008 became increasingly focused on IDPcamp closure, with the assisted return of IDPs to their communitiesor to alternative living situations.
Distúrbio Ondulatório de Leste e seus impactos na cidade de Salvador Wavelike easterly disturbance and its impacts on Salvador city  [cached]
Andréa Helena Machado dos Santos,Maria Regina da Silva Arag?o,Magaly de Fatima Correia,Heráclio Alves de Araujo
Revista Brasileira de Meteorologia , 2012, DOI: 10.1590/s0102-77862012000300010
Abstract: Um evento extremo de chuva registrado na cidade de Salvador, Bahia, é investigado neste trabalho. Dados observacionais de superfície e altitude, dados em pontos de grade, imagens de satélite meteorológico e informa es de desastres fornecidas pela Defesa Civil de Salvador (CODESAL) foram utilizados na análise. No período entre a meia noite e 3 horas da madrugada do dia 12 de junho de 2006, a precipita o acumulada foi de 51 mm. Um número elevado de ocorrências foi registrado pela CODESAL, notadamente deslizamentos de encosta. Ventos fracos em toda a troposfera e energia potencial convectiva disponível máxima de 3.233 J kg-1 foram diagnosticados em Salvador no dia 11 de junho, quinze horas antes do período de chuva forte. áreas de convec o profunda caracterizaram esse evento provocado por uma onda que chegou à costa leste do Nordeste do Brasil, após se propagar para oeste sobre o Atlantico Sul com velocidade de fase estimada de 10 m s-1, conforme evidenciado no campo da componente meridional do vento no nível de 700 hPa e em imagens de satélite meteorológico. An extreme rainfall event registered in the city of Salvador, Bahia, is investigated in this work. Observational surface and upper air data, gridpoint data, meteorological satellite images and disasters information provided by the Civil Defense of Salvador (CODESAL) were used in the analysis. During the period from midnight to 3 A.M. on 12 June 2006 51 mm accumulated rainfall was registered. A high number of disasters were registered by CODESAL, particularly landslides. Weak winds throughout the troposphere and maximum convective available potential energy of 3,233 J kg-1 were identified in Salvador on June 11th, fifteen hours before the heavy rainfall. Areas of deep convection characterized this event, favored by a wave that reached the eastern coast of Northeast Brazil after moving westward over the South Atlantic with an estimated phase speed of 10 m s-1, as seen on the meridional wind component field at the 700 hPa level and on meteorological satellite images.
CONSTRUCCIóN DE DISPOSITIVO PARA EVALUACIóN DEL DESGASTE EROSIVO EN SECO DE MATERIALES  [cached]
DAIRO HERNAN MESA GRAJALES,EDGAR MEJíA JARAMILLO,JOHNNY GARCíA VELAZQUEZ
Scientia Et Technica , 2004,
Abstract: Como manera de impulsar la investigación en el programa de Tecnología Mecánica de la UTP, a través de los conocimientos en el área de materiales y más específicamente en lo referente a la tribología (Desgaste, Fricción y Lubricación), se ha construido un dispositivo, con base en la norma ASTM G76/89, para evaluar la resistencia al desgaste erosivo en seco de materiales. En el dispositivo, las partículas duras son impulsadas a través de un ducto con ayuda de un chorro de aire a presión, pudiendo controlar la velocidad de impacto, el flujo y tama o de partículas, el ángulo y la distancia de las probetas al impacto de las partículas desde la salida del ducto, como también la forma y tama o de las probetas. El dispositivo fue calibrado sobre un acero inoxidable donde se controlaron las variables velocidad, flujo y ángulo de impacto de las partículas, consiguiéndose medir la resistencia al desgaste erosivo en seco a través del parámetro pérdida de masa generada en la probeta en el tiempo.
Estudio de la resistencia al desgaste erosivo en seco de materiales de ingeniería  [cached]
Johnny García Velásquez,Edgar Mejía Jaramillo,Dairo Hernán Mesa
DYNA , 2004,
Abstract: Se ha construido un dispositivo tipo gas-blast (chorro de gas), para evaluar la resistencia al desgaste erosivo en seco de algunos materiales de ingeniería, como aceros, aleaciones no ferrosas y materiales compuestos a base de resina plástica reforzada con fibras de vidrio. En el dispositivo, las partículas duras son impulsadas a través de un ducto con ayuda de un chorro de aire a presión, pudiéndose controlar la velocidad de impacto, el flujo y tama o de partículas, el ángulo y la distancia de las probetas al impacto de las partículas desde la salida del ducto, como también la forma y tama o de las probetas. A partir de los ensayos fue posible analizar la resistencia al desgaste erosivo en seco, en forma tanto cuantitativa como cualitativa, de algunos materiales de ingeniería, con ayuda de técnicas como fotografía de alta resolución, microscopía electrónica de barrido (MEB) y microanálisis químico.
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