Roberto Macedo Gamarra

Biotic factors and occurrence of Lutzomyia longipalpis in endemic area of visceral leishmaniasis, Mato Grosso do Sul, Brazil

The relationships between environmental exposure to risk agents and health conditions have been studied with the aid of remote sensing imagery, a tool particularly useful in the study of vegetation cover. This study aims to evaluate the influence of environmental variables on the spatial distribution of the abundance of Lutzomyia longipalpis and the reported canine and human visceral leishmaniasis (VL) cases at an urban area of Campo Grande, state of Mato Grosso do Sul. The sandfly captures were performed in 13 residences that were selected by raffle considering four residences or collection station for buffer. These buffers were generated from the central house with about 50, 100 and 200 m from it in an endemic area of VL. The abundance of sandflies and human and canine cases were georreferenced using the GIS software PCI Geomatica. The normalized difference vegetation index (NDVI) and percentage of land covered by vegetation were the environmental variables extracted from a remote sensing IKONOS-2 image. The average NDVI was considered as the complexity of habitat and the standard deviation as the heterogeneity of habitat. One thousand three hundred sixty-seven specimens were collected during the catch. We found a significant positive linear correlation between the abundance of sandflies and the percentage of vegetation cover and average NDVI. However, there was no significant association between habitat heterogeneity and the abundance of these flies.

Behavioral Aspects of Lutzomyia longipalpis (Diptera: Psychodidae) in Urban Area Endemic for Visceral Leishmaniasis

ABSTRACT The study of some of the behavioral aspects of the main vector of Leishmania infantum chagasi Cunha & Chagas in the Americas, Lutzomyia longipalpis (Lutz & Neiva), such as dispersion, population size, and vector survival rates, is important for the elucidation of the mechanisms of visceral leishmaniasis transmission. These parameters were studied by means of capture-mark-release-recapture experiments in an urban area of Campo Grande municipality, an endemic area of visceral leishmaniasis, situated in Mato Grosso do Sul state, Brazil. Six capture-mark-release-recapture experiments were undertaken between November 2009 and November 2010 and once in January 2012 with a view to assessing the population size and survival rate of Lu. longipalpis. The insects were released in a peridomicile surrounded by 13 residences. The recaptures were undertaken with automatic light traps for four consecutive weeks after release in the surrounding area. In total, 3,354 sand flies were captured, marked, and released. The overall recapture rate during the capture-markrelease-recapture experiments was 4.23%, of which 92.45% were recaptured at the release site, indicating limited dispersal. The greatest distance recorded from the release site was 165 m for males and 241 m for females. The male daily survival rate, calculated on the basis of regressions from the numbers of marked recaptured insects during the 15 successive days after release was 0.897. The estimated male population size measured by the Lincoln Index was 10,947.127. Though Lu. longipalpis presented a limited dispersion the physical barriers typical of urban environments did not prevent the sand flies from flying long distances.

Monthly Distribution of Phlebotomine Sand Flies, and Biotic and Abiotic Factors Related to Their Abundance, in an Urban Area to Which Visceral Leishmaniasis Is Endemic in Corumba, Brazil

The monthly distribution and abundance of sand flies are influenced by both biotic and abiotic factors. The present study aimed to evaluate the seasonal distribution of sand flies and the relation between their abundance and environmental parameters, including vegetation and climate. This study was conducted over a 2-year period (April 2012 to March 2014). Monthly distribution was evaluated through the weekly deployment of CDC light traps in the peridomicile area of 5 residences in an urban area of the municipality of Corumbá in the State of Mato Grosso do Sul, Brazil. Meteorological data were obtained from the Mato Grosso do Sul Center for Weather, Climate, and Water Resources. The spectral indices were calculated based on spatial resolution images (GeoEye) and the percentage of vegetal coverage. Differences in the abundance of sand flies among the collection sites were assessed using the Kruskal-Wallis test, and the strength of correlations between environmental variables was determined by calculating Spearman’s correlation coefficients. Lutzomyia cruzi, Lu. forattinii, and Evandromyia corumbaensis were the most frequently found species. Although no significant association was found among these sand fly species and the tested environmental variables (vegetation and climate), high population peaks were found during the rainy season, whereas low peaks were observed in the dry season. The monthly distribution of sand flies was primarily determined by Lu. cruzi, which accounted for 93.94% of the specimens collected each month throughout the experimental period. The fact that sand flies were detected year-round indicates a continuous risk of infection to humans, demonstrating the need for targeted management and education programs.

The 2009 earthquake, magnitude mb 4.8, in the Pantanal Wetlands, west-central Brazil

The main goal of this paper is to characterize the Coxim earthquake occurred in June 15th, 2009 in the Pantanal Basin and to discuss the relationship between its faulting mechanism with the Transbrasiliano Lineament. The earthquake had maximum intensity MM V causing damage in farm houses and was felt in several cities located around, including Campo Grande and Goiânia. The event had an mb 4.8 magnitude and depth was 6 km, i.e., it occurred in the upper crust, within the basement and 5 km below the Cenozoic sedimentary cover. The mechanism, a thrust fault mechanism with lateral motion, was obtained by P-wave first-motion polarities and confirmed by regional waveform modelling. The two nodal planes have orientations (strike/dip) of 300°/55° and 180°/55° and the orientation of the P-axis is approximately NE-SW. The results are similar to the Pantanal earthquake of 1964 with mb 5.4 and NE-SW compressional axis. Both events show that Pantanal Basin is a seismically active area, under compressional stress. The focal mechanism of the 1964 and 2009 events have no nodal plane that could be directly associated with the main SW-NE trending Transbrasiliano system indicating that a direct link of the Transbrasiliano with the seismicity in the Pantanal Basin is improbable.

USO DE GEOTECNOLOGIAS PARA O ESTABELECIMENTO DE ÁREAS PARA CORREDORES DE BIODIVERSIDADE

Corredores de biodiversidade sao estruturas ambientais com a finalidade de conservar e recuperar a biodiversidade. Aplicam-se, principalmente, a areas degradadas pelo desenvolvimento humano desordenado, que favorece a fragmentacao florestal e a perda da conectividade entre os diversos habitats. Utilizando o sensoriamento remoto e sistemas de informacoes geograficas, buscou-se identificar areas para atuarem como corredores de biodiversidade, possibilitando, assim, o fluxo genico entre os fragmentos remanescentes e as areas de preservacao permanente. Para tanto, foi realizada uma analise espacial dos fragmentos remanescentes em Sao Gabriel do Oeste, Mato Grosso do Sul, atraves de sua forma, tamanho e localizacao. Foram identificadas as areas para os corredores a partir da localizacao de fragmentos com potencial, ou seja, de tamanho e conservacao adequados, alem de considerar a carta de classes das terras para mecanizacao e o mapa de areas prioritarias para a conservacao do Ministerio do Meio Ambiente, permitindo a escolha de melhores areas para corredores de biodiversidade. Verificou-se que as geotecnologias sao importantes ferramentas de auxilio na determinacao de areas propicias para a analise integrada da paisagem, bem como de areas propicias para implantacao de corredores, gerando um cenario alternativo para a recuperacao ambiental, o zoneamento ecologico e a conservacao ambiental.

Remoto Plant Structure Analysis of Cerrado Fragments by Remote Sensing

With the development of society to preserve the environment becomes essential. Biodiversity is a resource that has strategic value and is related to the territorial heterogeneity. The loss and fragmentation of natural habitats is one of the greatest threats to biodiversity resulting biotic and abiotic changes in the remaining. The Cerrado occupied 23% of the Brazilian territory in the plains of the central plateau. Estimates indicates that the Cerrado will be completely destroyed in 2030. The environmental heterogeneity contributes to the high species richness and from the environmental services offering stands out the protection of water resources. This study aims to analyze the structural vegetation of 18 Cerrado fragments by multi-temporal composite applied to Normalized Difference Vegetation Index and Normalized Difference Water Index. Both indices were calculated using Landsat images 1985-2015 and a falsecolor composite was then generated to detect changes in vegetation cover. It was possible to detect changes in vegetation cover and moisture over time. The false-color multi-temporal combination proved to be a quick and easy way to locate the places where there have been changes in vegetation cover.Com o desenvolvimento das sociedades, a preservacao do meio ambiente se torna imprescindivel.A perda e a fragmentacao dos habitats naturais constituem uma das maiores ameacas a biodiversidade provocando alteracoes de origem biotica e abiotica nos remanescentes florestais, como os encontrados no bioma cerrado, que chegou a ocupar 23% do territorio brasileiro. A heterogeneidade ambiental contribui para a elevada riqueza de especies e dentre os servicos ambientais que oferece se destaca a protecao aos recursos hidricos. O objetivo deste trabalho foi analisar a estrutura da vegetacao de fragmentos de Cerrado por meio de composicao multitemporal,baseada nos Indice de Vegetacao por Diferenca Normalizada e Indice de Umidade por Diferenca Normalizada. Ambos os indices foram aplicados sobre imagens Landsat de 1985 a 2015. Posteriormente foi gerada uma composicao falsa-cor para detectar mudancas na cobertura vegetal. Foi possivel detectar mudancas da cobertura vegetal e de umidade ao longo dos trinta anos entre 1985 e 2015. A combinacao falsa-cor multitemporal se mostrou uma maneira simples e rapida para se localizar os locais onde houve mudancas na cobertura vegetal.

Análise das Mudanças da Cobertura do Solo de uma Área de Cerrado (Savana Tropical) no Centro-Oeste do Brasil

The objective of the present work was to carry out an analysis of the land cover of an area in the centre-west of Brazil, at two different times, in 1966 and 2001, using a satellite image and a topographic map, in the Geographic Information System (GIS) environment. The 1966 land cover map was obtained by vectorizing the SE-22-Y-A-V topographic map (IBGE), while the 2001 land cover map was obtained from supervised automatic classification of the Landsat image ETM+ satellite orbit/point 224/073 of August 2001. The analysis showed alterations from natural cover to anthropogenic. In 1966, natural cover was 90% or more (principally true cerrado and forest), while in 2001, natural cover had decreased to 24%, being replaced by arable land and primarily grassland.

Modelo de Estabilidade dos Solos a Erosão

The development of new techniques that facilitate environmental planning are needed, so this work presents a new methodological approach : the Model of Stability of Soil Science (MES) , which uses data obtained by remote sensing in order to support environmental planning . The technique was applied in the city of Costa Rica - MS with Landsat generating an environmental zoning proposal for the study area. The letter slope was drawn through the SRTM digital elevation model. The Charter Fitness of Lands (agricultural capability of the soil) was obtained from the Multi Referral Atlas of the State of Mato Grosso do Sul linear spectral mixture model to derive vegetation fraction image ( letter of vegetation cover ) was used . With this data set we applied the MES through map algebra, which uses the overlay of information layers slope, agricultural soil suitability and land cover. Data obtained via MES were compared with those observed in the field. Thus it can be seen that the MES was efficient in assessing the areas most vulnerable to the erosive action, moreover, proved to be an efficient tool for decision making.