834 resultados para Riparian corridors


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Land use and transportation interaction has been a research topic for several decades. There have been efforts to identify impacts of transportation on land use from several different perspectives. One focus has been the role of transportation improvements in encouraging new land developments or relocation of activities due to improved accessibility. The impacts studied have included property values and increased development. Another focus has been on the changes in travel behavior due to better mobility and accessibility. Most studies to date have been conducted in metropolitan level, thus unable to account for interactions spatially and temporally at smaller geographic scales. ^ In this study, a framework for studying the temporal interactions between transportation and land use was proposed and applied to three selected corridor areas in Miami-Dade County, Florida. The framework consists of two parts: one is developing of temporal data and the other is applying time series analysis to this temporal data to identify their dynamic interactions. Temporal GIS databases were constructed and used to compile building permit data and transportation improvement projects. Two types of time series analysis approaches were utilized: univariate models and multivariate models. Time series analysis is designed to describe the dynamic consequences of time series by developing models and forecasting the future of the system based on historical trends. Model estimation results from the selected corridors were then compared. ^ It was found that the time series models predicted residential development better than commercial development. It was also found that results from three study corridors varied in terms of the magnitude of impacts, length of lags, significance of the variables, and the model structure. Long-run effect or cumulated impact of transportation improvement on land developments was also measured with time series techniques. The study offered evidence that congestion negatively impacted development and transportation investments encouraged land development. ^

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Isla del Coco (Cocos Island) is a small volcanic island located in the Pacific 500 km west of Costa Rica. Three collecting trips to Isla del Coco, in addition to herbarium research, were completed in order to assess the floristic diversity of the island. The current flora of Isla del Coco contains 262 plant species of which 37 (19.4%) are endemic. This study reports 58 species as new to the island. Seventy-one species (27.1%) were identified as introduced by humans. In addition, five potentially invasive plant species are identified. Seven vegetation types are identified on the island: bayshore, coastal cliff, riparian, low elevation humid forest, high elevation cloud forest, landslide and islet. ^ The biogeographic affinities of the native and endemic species are with Central America/northern South America and to a lesser extent, the Caribbean. Endemic species in the genus Epidendrum were investigated to determine whether an insular radiation event had produced two species found on Isla del Coco. Phylogenetic analysis of the internal transcribed spacer (ITS) of nuclear ribosomal DNA was not able to disprove that the endemic species in this genus are not sister species. Molecular biogeographic analyses of ITS sequence data determined that the Isla del Coco endemic species in the genera Epidendrum, Pilea and Psychotria are most closely related to Central American/northern South American taxa. No biogeographical links were found between the floras of Isla del Coco and the Galápagos Islands. ^ The native and endemic plant diversity of Isla del Coco is threatened with habitat degradation by introduced pigs and deer, and to a lesser extent, by exotic plant species. The IUCN Red List and RAREplants criteria were used to assess the extinction threat for the 37 endemic plant taxa found on the island. All of the endemic species are considered threatened with extinction at the Critically Endangered (CR) by the IUCN criteria or either CR or Endangered (EN) using RAREplants methodology. ^

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To chronicle demographic movement across African Asian corridors, a variety of molecular (sequence analysis, restriction mapping and denaturing high performance liquid chromatography etc.) and statistical (correspondence analysis, AMOVA, calculation of diversity indices and phylogenetic inference, etc.) techniques were employed to assess the phylogeographic patterns of mtDNA control region and Y chromosomal variation among 14 sub-Saharan, North African and Middle Eastern populations. The patterns of genetic diversity revealed evidence of multiple migrations across several African Asian passageways as well within the African continent itself. The two-part analysis uncovered several interesting results which include the following: (1) a north (Egypt and Middle East Asia) to south (sub-Saharan Africa) partitioning of both mtDNA and Y chromosomal haplogroup diversity, (2) a genetic diversity gradient in sub-Saharan Africa from east to west, (3) evidence in favor of the Levantine Corridor over the Horn of Africa as the major genetic conduit since the Last Glacial Maximum, (4) a substantially higher mtDNA versus Y chromosomal sub-Saharan component in the Middle East collections, (5) a higher representation of East versus West African mtDNA haplotypes in the Arabian Peninsula populations versus no such bias in the Levant groups and lastly, (6) genetic remnants of the Bantu demographic expansion in sub-Saharan Africa. ^

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Bonefish (Albula spp.) support an economically important catch-and-release recreational fishery, as well as artisanal harvesting, in The Bahamas. Little is known about the large-scale movement patterns of bonefish, yet such information is essential for proper species conservation and management. ^ I used acoustic telemetry to determine large-scale movement patterns of bonefish around Andros, Bahamas, in conjunction with presumed spawning migrations. I conclude that bonefish travel long distances from shallow flats to pre-spawning aggregation sites in proximity to off-shore reef locations. Off-shore movement to deeper reef locations occurs around both new and full moons. This study has also confirmed anecdotal reports that the North Bight is an important spawning migration corridor for bonefish. ^ This information is critical for the protection of bonefish and identifies important habitats (e.g. migration corridors and pre-spawning aggregations) on Andros that warrant protection from coastal degradation or fishing pressures. ^

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Freshwater ecosystems have been recognized as important components of the global carbon cycle, and the flux of organic matter (OM) from freshwater to marine environments can significantly affect estuarine and coastal productivity. The focus of this study was the assessment of carbon dynamics in two aquatic environments, namely the Florida Everglades and small prairie streams in Kansas, with the aim of characterizing the biogeochemistry of OM. In the Everglades, particulate OM (POM) is mostly found as a layer of flocculent material (floc). While floc is believed to be the main energy source driving trophic dynamics in this oligotrophic wetland, not much is known about its biogeochemistry. The objective of this study was to determine the origin/sources of OM in floc using biomarkers and pigment-based chemotaxonomy to assess specific biomass contributions to this material, on a spatial (freshwater marshes vs. mangrove fringe) and seasonal (wet vs. dry) scales. It was found that floc OM is derived from the local vegetation (mainly algal components and macrophyte litter) and its composition is controlled by seasonal drivers of hydrology and local biomass productivity. Photo-reactivity experiments showed that light exposure on floc resulted in photo-dissolution of POC with the generation of significant amounts of both dissolved OM (DOM) and nutrients (N & P), potentially influencing nutrient dynamics in this ecosystem. The bio-reactivity experiments determined as the amount and rate of CO2 evolution during incubation were found to vary on seasonal and spatial scales and were highly influenced by phosphorus limitation. Not much is known on OM dynamics in small headwater streams. The objective of this study was to determine carbon dynamics in sediments from intermittent prairie streams, characterized by different vegetation cover for their watershed (C4 grasses) vs. riparian zone (C3 plants). In this study sedimentary OM was characterized using a biomarker and compound specific carbon stable isotope approach. It was found that the biomarker composition of these sediments is dominated by higher plant inputs from the riparian zone, although inputs from adjacent prairie grasses were also apparent. Conflicting to some extent with the River Continuum Concept, sediments of the upper reaches contained more degraded OM, while the lower reaches were enriched in fresh material deriving from higher plants and plankton sources as a result of hydrological regimes and particle sorting.

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Bonefish (Albula spp.) support an economically important catch-and-release recreational fishery, as well as artisanal harvesting, in The Bahamas. Little is known about the large-scale movement patterns of bonefish, yet such information is essential for proper species conservation and management. I used acoustic telemetry to determine large-scale movement patterns of bonefish around Andros, Bahamas, in conjunction with presumed spawning migrations. I conclude that bonefish travel long distances from shallow flats to pre-spawning aggregation sites in proximity to off-shore reef locations. Off-shore movement to deeper reef locations occurs around both new and full moons. This study has also confirmed anecdotal reports that the North Bight is an important spawning migration corridor for bonefish. This information is critical for the protection of bonefish and identifies important habitats (e.g. migration corridors and pre-spawning aggregations) on Andros that warrant protection from coastal degradation or fishing pressures.

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The goal of this study was to determine the instantaneous vs. integrated effects of waste on the water quality of the Chorobamba River. I sampled 9 stations upstream and downstream of the Town of Oxapampa, Peru during the dry season (June-August) of 2004. I measured in-situ parameters such as pH, DO, temperature, etc. as well as vegetation, riverbank erosion, nutrients (N03, NH4, P04), coliform bacteria and macroinvertebrate communities to determine the current conditions of the river, as well as the integrated effects of pollution. Although water quality conditions remained stable, high fecal coliform concentrations and macroinvertebrate communities indicate deterioration in river health over a longer period of time. If riparian areas along the Chorobamba continue to decrease and if inputs of sewage into the rivers continue to increase, as a function of population, then, conditions will continue to deteriorate in the coming years.

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Deforestation in the tropical Andes is affecting ecological conditions of streams, and determination of how much forest should be retained is a pressing task for conservation, restoration and management strategies. We calculated and analyzed eight benthic metrics (structural, compositional and water quality indices) and a physical-chemical composite index with gradients of vegetation cover to assess the effects of deforestation on macroinvertebrate communities and water quality of 23 streams in southern Ecuadorian Andes. Using a geographical information system (GIS), we quantified vegetation cover at three spatial scales: the entire catchment, the riparian buffer of 30 m width extending the entire stream length, and the local scale defined for a stream reach of 100 m in length and similar buffer width. Macroinvertebrate and water quality metrics had the strongest relationships with vegetation cover at catchment and riparian scales, while vegetation cover did not show any association with the macroinvertebrate metrics at local scale. At catchment scale, the water quality metrics indicate that ecological condition of Andean streams is good when vegetation cover is over 70%. Further, macroinvertebrate community assemblages were more diverse and related in catchments largely covered by native vegetation (>70%). Overall, our results suggest that retaining an important quantity of native vegetation cover within the catchments and a linkage between headwater and riparian forests help to maintain and improve stream biodiversity and water quality in Andean streams affected by deforestation. Also, this research proposes that a strong regulation focused to the management of riparian buffers can be successful when decision making is addressed to conservation/restoration of Andean catchments.

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In this work the landscape morphodynamics was used to check the strength and importance of the changes carried out by man on the environment over time, in Natal-RN municipality. The occupation of partially preserved natural areas was analyzed, but environmentally fragile, such as riparian forests, vegetation on the banks of waterways, which play regulatory role of the water flow, and the dunes, which guarantee the rapid recharge of aquifers. The impacts of urban sprawl in Natal Southern and West zones Were identified and characterized, through a detailed mapping in the period between 1969 and 2013 the main Permanent Preservation Areas - PPA (banks of rivers and lagoons, and dunes remaining) and their temporal changes. For this were used aerial photographs and satellite imagery, altimetry data, and pre-existing information, which allowed the creation of a spatial database, and evolution of maps of impervious areas, evolution of the use and occupation and Digital Terrain Model (DTM) from contour lines with contour interval of 1 meter. Based on this study presents a diagnosis of the environmental situation and the state of conservation of natural areas, over the last 44 years, compared to human pressures. In general, it was found that the urban settlement has advanced about 60% of studied natural areas. This advance was growing by the year 2006, when there was a slowdown in the process, except for the Environmental Protection Zone (EPZ) 03, where the river Pitimbú and your PPA, which experienced a more significant loss area. The urban occupation affected the natural drainage and contributed to the contamination of groundwater Natal, due to increased sealed area, the release of liquid and solid waste, as well as the removal of riparian vegetation. Changed irreversibly the natural landscape, and reduced the quality and quantity of water resources necessary for the population. Thus, it is necessary to stimulate the adoption of use and protection of PPA planning measures, to the preservation of the San Valley Region inserted into the EPZ 01, and integrate more remaining dunes, in good condition, this EPZ, due to the importance of those remaining on the environment and the maintenance of quality of life. It is suggested, also, protection of catchment areas, such as PPA ponds and Pitimbú River. Finally, it is expected that this study can assist the managers in making decisions in urban and environmental planning of the municipality

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The longshore sediment transport (LST) is determinant for the occurrence of morphological changes in coastal environments. Understanding their movement mechanisms and transport is an essential source of information for the project design and coastal management plans. This study aims to characterize, initially, the active hydrodynamic circulation in the study area, comprised of four beach sectors from the south coast of Natal, assessing the average annual LST obtained through three proven equations (CERC, Kamphuis and Bayram et al.), defining the best formulation for the study area in question, and analyze the seasonal variability and the decadal transport evolution. The coastal area selected for this work constitutes one of the main tourist corridors in the city, but has suffered serious damage resulting from associated effects of hydrodynamic forcings and their disorderly occupation. As a tool was used the Coastal Modelling System of Brazil (SMC-Brazil), which presents integrated a series of numerical models and a database, properly calibrated and validated for use in developing projects along the Brazilian coastline. The LST rates were obtained for 15 beach profiles distributed throughout the study area. Their extensions take into account the depth of closure calculated by Harllermeier equation, and regarding the physical properties of the sediment, typical values of sandy beaches were adopted, except for the average diameter, which was calculated through an optimization algorithm based on equilibrium profile formulation proposed by Dean. Overall, the results showed an intensification of hydrodynamic forcings under extreme sea wave conditions, especially along the headlands exist in the region. Among the analyzed equations, Bayram et al. was the most suitable for this type of application, with a predominant transport in the south-north direction and the highest rates within the order of 700.000 m3 /year to 2.000.000 m3 /year. The seasonal analysis also indicated a longitudinal transport predominance in the south to north, with the highest rates associated with the fall and winter seasons. In these periods are observed erosive beach states, which indicate a direct relationship between the sediment dynamics and the occurrence of more energetic sea states. Regarding the decadal evolution of transportation, it was found a decrease in transport rate from the 50’s to the 70’s, followed by an increase until the 2000’s, coinciding with the beginning of urbanization process in some stretches of the studied coastline.

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Reservoirs are artificial ecosystems intermediate between rivers and lakes widely used in the Brazilian semiarid region as a way to provide water supply due to the said region’s water scarcity. The use of water from these supply sources for multiple uses, along with occupation and utilization of its riparian zone without proper management, directly influences the increased nutrient flow into aquatic environments, there with contributing to the acceleration of eutrophication. The semi-arid region is characterized by peculiar weather conditions, such as severe evaporation, high temperatures with little variation throughout the year and long water residence time, making it susceptible to prolonged drought occurrence, which tends to concentrate the nutrients in reservoirs, which favors the development of eutrophic conditions. Moreover, it is common soil use and occupation by carrying out activities with potential environmental impact on natural resources such as agriculture, livestock farming and lack of sanitation. The aim of this study is both to evaluate the water quality of the Cruzeta Reservoir, located in the semiarid region of Rio Grande do Norte, during a prolonged drought period, and assess the quality of its riparian zone soil under different uses, by monitoring physical-chemical variables. Along the prolonged drought, high levels of turbidity, suspended solids, nutrients and chlorophyll a were verified as present, therefore featuring low water quality. In the riparian zone of Cruzeta Reservoir, the areas under use of agriculture and livestock farming appeared as one of the main diffuse sources of nutrients to the said reservoir, featuring the highest levels of phosphorus and nitrogen in the soil, originated from decomposition of animal excreta and from the use of fertilizers, creating a tendency to increased eutrophication of such water supply source. The indicators of water and soil quality are useful for monitoring and evaluating the conservation status of natural resources, allowing the control and mitigation of the reservoir eutrophication process. This study confirmed the hypothesis that the reduction of water level, resulting from prolonged drought event, aggravates the symptoms of eutrophication; and also that using the soil under severalways modifies the physic chemical properties of the soil, having livestock farming and agriculture as the usages with greatest potential towards yielding P and N to the aquatic environment.

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Human activities alter soil features, causing the deterioration of its quality. Land use and occupation in drainage basins of water supply reservoirs can change the environmental soil quality and, thus, lead to the expansion of the soil potential of being a diffuse pollution source. In the Brazilian semiarid region, the soils are generally shallow with high susceptibility to erosion, favoring the sediment and nutrients input into the superficial waterbodies, contributing to the eutrophication process. Moreover, this region has high temperatures and high evapotranspiration rates, that are generally higher than the precipitation rates, causing a negative hydric balance and big volume losses by evaporation. The water volume reduction increases the nutrients’ concentration and, therefore, exacerbates the eutrophication process, deteriorating the water quality. Thereby, we hypothesized that the eutrophication process of semiarid reservoirs is intensified both by the extreme climatic events of prolonged drought, and by the diffuse pollution due to the basin land use and occupation. The study aimed to test whether the land use and occupation activities of the basin and the severe drought events intensify the eutrophication process of a semiarid tropical reservoir. To verify the influence of human activities carried out in the water supply of drainage basin on the soil quality and the eutrophication process, we conducted the mapping of the kind of use and occupation, as well the calculation of erosion for each activity and the soil quality evaluation of the riparian zone and water quality of the water supply. For the water analyses, the samplings were carried out monthly in the deeper point, near dam. For the soil, deformed composite samples were taken for the physical and chemical attributes analysis, according to the identified land use and occupation classes. The results showed that extreme droughts drastically reduces the water volume and elevates the nutrients concentration, contributing, thus, to a bigger degradation of water quality. Furthermore, we verified that human activities in the drainage basin promote the diffuse pollution, by increasing the soil susceptibility to erosion and nutrients contents. Summarizing, our results support the investigated hypothesis that activities of land use and occupation and extreme drought generate a combined effect that provide the intensification of eutrophication process of semiarid reservoirs.

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Some of the current discussions in the teaching of Portuguese Language (LP) pertain to how the school should deal with the phenomenon of language variation in the classroom. In 2010, for example, an explosion of talk took over the academic corridors: a book, entitled "Por uma vida melhor", the collection "Viver, Aprender", published by the MEC (Ministry of Education and Culture) to students EJA (Youth and Adults) brought notions regarding linguistic variation, even in their first chapter. In it is clear the notion that it is possible to make use of structures as "pretty boy", instead of "pretty boys", depending on the context in which such use is insert. Therefore, the discussions focused around the notions of variety cultivated, standard and popular measuring them to the possibilities of linguistic appropriateness. The community was surprised by the defense of the "power" to use, since it would be the school space to teach a standard "default", and not the possibility of legitimate use of grammatical patterns that clashed with those recommended in traditional grammars. The television media has been responsible for a major blaze that MEC had endorsed the use in schools of a book that legitimized such linguistic patterns. The quarrel was released on Youtube and in that space, netizens expressed themselves for or against the proposal of LD often directing the discussion to questions of a purely political. We observed that, on one side, loomed arguments related to Sociolinguistics (BAGNO , 2002, 2003, 2007, 2009; BAGNO, M.; STUBBS, M., Gagne, G., 2006; Bortoni - RICARDO, S.M., 2008; Tarallo, F., 1982; U. Weinreich, MARVIN I. HERZOG, Labov, W., 1968, Labov 1972, etc.); another, arguments concentrated on defending the school is the area of language teaching standard, and not fit to bring certain discussions within an LD. It was from these words, that this research was born. Interested in the particular way that the community media, which seemed to have no training in linguistics, understand the concepts of right, wrong, appropriate and inappropriate, so intimate in academic circles. Our thoughts take as reference the theoretical studies on the question of sociolinguistic variation and education, official documents that guide the "work" with the Portuguese language in the classroom, like the NCP (National Curriculum) and Curriculum Proposal for Education Youth and Adult (PCEJA). In our analysis, we found that LD" For a better life "makes no apology for teaching the "error", but it raises discussions about the possibility of "change", linked to factors and different order. We realize how significant it is to observe how speakers of a language are positioned in relation to language teaching which they are not speakers and scholars. Our study showed that certain issues regarding the teaching of the Portuguese language, as is the case of linguistic variation, points are far from being resolved, either for linguists and/or grammarians, whether for language speakers.

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As florestas ribeirinhas se dividem em matas ciliares e matas de galeria. As matas de galeria são importantes na manutenção dos recursos hídricos e da fauna a elas associada. Esses ambientes sofrem degradação e para a conservação e restauração são necessários estudos que entendam o funcionamento das espécies na comunidade. Os objetivos desse trabalho foram avaliar a variabilidade na área foliar específica em mata de galeria inundável do córrego do Glória (Uberlândia/MG) e mata de galeria não-inundável do ribeirão do Panga (Uberlândia/MG) e utilizar atributos reprodutivos como síndrome de polinização, síndrome de dispersão e sistema sexual, para comparação entre distintas áreas de mata de galeria inundável e também comparando com a mata de galeria não-inundável do Panga. Foram utilizados os dados florísticos já realizados nas matas de galeria não inundável do Panga (Uberlândia/MG), da mata de galeria inundável do Glória (Uberlândia/MG) e diversas outras matas de galeria inundável. A partir desses estudos foram calculados o IVC (Índice de Valor de Cobertura) e selecionadas as espécies. Para avaliar a variabilidade da área foliar específica foram utilizadas e as médias de AFE (área foliar específica) das espécies para comparação entre as duas áreas com o teste t de Student; já para analisar os padrões reprodutivos entre as matas de galeria inundável e compará-las com os padrões do Panga foram feitos testes de qui-quadrado. Os resultados do teste t mostraram que as médias das espécies da mata de galeria do Glória foram significativamente maiores do que as médias da mata de galeria do Panga. Protium heptaphyllum foi a única espécie co-ocorrente e também apresentou média significativamente maior na mata de galeria do Glória. As espécies vegetais com maiores AFE possuem uma maior captação de luz por unidade de biomassa investida, mas tendem a ter maior evaporação e perda de água. Por isso, a mata de galeria inundável, que não tem restrição hídrica para as espécies, pode apresentar maiores lâminas foliares. Com relação aos três atributos reprodutivos analisados, as áreas mostraram ser diferentes entre si e através de representação gráfica pode-se analisar que não houve padrões definidos entre as áreas, mas uma tendência a semelhanças entre várias áreas, principalmente em áreas próximas geograficamente, como as áreas de Uberlândia/MG. Quando comparados a padrões encontrados em outros estudos, as matas de galeria são semelhantes a outras áreas de floresta tropical, como alto índice de dioicia, que é relacionado a ambientes úmidos, maior porcentagem de dispersão zoocórica, especialmente por aves, e maior porcentagem de polinizadores generalistas, que são geralmente associados à dioicia.

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The various types of pig farming, intensive and extensive, expose them to pig parasites but also to those from the environment of the breeding site. In this work was evaluated the exposure of bigs bred in technified farms, SISCAL (intensive breeding system in pens) and not technified (backyard) to leptospira, ticks and rickettsiae. Blood sera were analyzed to determine titers of antibodies anti-Leptospira by SAM technique and antibodies anti-rickettsial by IFA, pigs were inspected for ticks and in their breeding environment and surrounding areas (pastures and riparian vegetation), ticks were collected by the flannel dragging technique. In the farms of pigs 10.4% had anti-Leptospira antibodies, followed by SISCAL (8%) and backyard animals (2.5%). The serovars found were Bratislava, Pomona, serovar, Canicola and Icterohaemorrhagiae. Higher percentage of properties with pigs raised outdoors (SISCAL) had tick infested animals (20%) than those raised in backyard (6.7%), while commercial farms had no infested pigs nor infested breeding place. In both SISCAL and backyard pig breeding properties ticks were observed at the breeding site environment. Tick infestations were detected in areas surrounding pig breeding site in all three husbandry suystems. Ticks found were all Amblyomma scultpum nymphs or adults with the exception of one of Amblyomma parvum adult. In relation to anti-rickettsia serology to five Rickettsia species, 55.2% of pigs from commercial farms reacted to al least one species, backyard pigs reacted to 89.7% and all pigs of SISCAL showed anti-rickettsia titers. Consecutive tick sampling (June 2014 to February 2016) in SISCAL FAZU in Uberaba, showed the establishment A. sculptum ticks maintained by domestic pigs. These observations demonstrate the ability the pigs to maintain populations of A. sculptum at a favorable environment and may indicate a new trend in environmental infestations by this species of tick. Exposure to Leptospira and Rickettsia demonstrated the potential pigs exposure and transmission of important diseases in public health.