USE OF SCALED SEMIVARIOGRAMS IN THE PLANNING SAMPLE OF SOIL CHEMICAL PROPERTIES IN SOUTHERN AMAZONAS, BRAZIL

The lack of information concerning the variability of soil properties has been a major concern of researchers in the Amazon region. Thus, the aim of this study was to evaluate the spatial variability of soil chemical properties and determine minimal sampling density to characterize the variability of these properties in five environments located in the south of the State of Amazonas, Brazil. The five environments were archaeological dark earth (ADE), forest, pasture land, agroforestry operation, and sugarcane crop. Regular 70 × 70 m mesh grids were set up in these areas, with 64 sample points spaced at 10 m distance. Soil samples were collected at the 0.0-0.1 m depth. The chemical properties of pH in water, OM, P, K, Ca, Mg, H+Al, SB, CEC, and V were determined at these points. Data were analyzed by descriptive and geostatistical analyses. A large part of the data analyzed showed spatial dependence. Chemical properties were best fitted to the spherical model in almost all the environments evaluated, except for the sugarcane field with a better fit to the exponential model. ADE and sugarcane areas had greater heterogeneity of soil chemical properties, showing a greater range and higher sampling density; however, forest and agroforestry areas had less variability of chemical properties.

SOIL PHOSPHORUS THRESHOLDS IN EVALUATING RISK OF ENVIRONMENTAL TRANSFER TO SURFACE WATERS IN SANTA CATARINA, BRAZIL

The State of Santa Catarina, Brazil, has agricultural and livestock activities, such as pig farming, that are responsible for adding large amounts of phosphorus (P) to soils. However, a method is required to evaluate the environmental risk of these high soil P levels. One possible method for evaluating the environmental risk of P fertilization, whether organic or mineral, is to establish threshold levels of soil available P, measured by Mehlich-1 extractions, below which there is not a high risk of P transfer from the soil to surface waters. However, the Mehlich-1 extractant is sensitive to soil clay content, and that factor should be considered when establishing such P-thresholds. The objective of this study was to determine P-thresholds using the Mehlich-1 extractant for soils with different clay contents in the State of Santa Catarina, Brazil. Soil from the B-horizon of an Oxisol with 800 g kg-1 clay was mixed with different amounts of sand to prepare artificial soils with 200, 400, 600, and 800 g kg-1 clay. The artificial soils were incubated for 30 days with moisture content at 80 % of field capacity to stabilize their physicochemical properties, followed by additional incubation for 30 days after liming to raise the pH(H2O) to 6.0. Soil P sorption curves were produced, and the maximum sorption (Pmax) was determined using the Langmuir model for each soil texture evaluated. Based on the Pmax values, seven rates of P were added to four replicates of each soil, and incubated for 20 days more. Following incubation, available P contents (P-Mehlich-1) and P dissolved in the soil solution (P-water) were determined. A change-point value (the P-Mehlich-1 value above which P-water starts increasing sharply) was calculated through the use of segmented equations. The maximum level of P that a soil might safely adsorb (P-threshold) was defined as 80 % of the change-point value to maintain a margin for environmental safety. The P-threshold value, in mg dm-3, was dependent on the soil clay content according to the model P-threshold = 40 + Clay, where the soil clay content is expressed as a percentage. The model was tested in 82 diverse soil samples from the State of Santa Catarina and was able to distinguish samples with high and low environmental risk.

Estimating soybean crop areas using spectral-temporal surfaces derived from MODIS images in Mato Grosso, Brazil

The objective of this work was to evaluate the application of the spectral-temporal response surface (STRS) classification method on Moderate Resolution Imaging Spectroradiometer (MODIS, 250 m) sensor images in order to estimate soybean areas in Mato Grosso state, Brazil. The classification was carried out using the maximum likelihood algorithm (MLA) adapted to the STRS method. Thirty segments of 30x30 km were chosen along the main agricultural regions of Mato Grosso state, using data from the summer season of 2005/2006 (from October to March), and were mapped based on fieldwork data, TM/Landsat-5 and CCD/CBERS-2 images. Five thematic classes were considered: Soybean, Forest, Cerrado, Pasture and Bare Soil. The classification by the STRS method was done over an area intersected with a subset of 30x30-km segments. In regions with soybean predominance, STRS classification overestimated in 21.31% of the reference values. In regions where soybean fields were less prevalent, the classifier overestimated 132.37% in the acreage of the reference. The overall classification accuracy was 80%. MODIS sensor images and the STRS algorithm showed to be promising for the classification of soybean areas in regions with the predominance of large farms. However, the results for fragmented areas and smaller farms were less efficient, overestimating soybean areas.

Radiological findings of pulmonary tuberculosis in indigenous patients in Dourados, MS, Brazil

AbstractObjective:To describe the radiological findings of pulmonary tuberculosis in indigenous patients from the city of Dourados, MS, Brazil, according to age and sex.Materials and Methods:Chest radiographic images of 81 patients with pulmonary tuberculosis, acquired in the period from 2007 to 2010, were retrospectively analyzed by two radiologists in consensus for the presence or absence of changes. The findings in abnormal radiographs were classified according to the changes observed and they were correlated to age and sex. The data were submitted to statistical analysis.Results:The individuals' ages ranged from 1 to 97 years (mean: 36 years). Heterogeneous consolidations, nodules, pleural involvement and cavities were the most frequent imaging findings. Most patients (55/81 or 67.9%) were male, and upper lung and right lung were the most affected regions. Fibrosis, heterogeneous consolidations and involvement of the left lung apex were significantly more frequent in males (p < 0.05). Presence of a single type of finding at radiography was most frequent in children (p < 0.05).Conclusion:Based on the hypothesis that indigenous patients represent a population without genetically determined resistance to tuberculosis, the present study may enhance the knowledge about how the pulmonary form of this disease manifests in susceptible individuals.

Native species indicated for degraded area recovery in Western Paraná, Brazil

Colonization in the State of Paraná has culminated in the devastation of large forest areas in the entire State. Degraded area recovery programs have emphasized the utilization of native species, but often the species indicated for local reforestation areas are unknown, as those areas are little known floristically. This study aimed to survey native species indicated for reforestation of areas in the Western region of the State of Paraná, classify those species as pioneer, secondary, or climactic, and indicate places of occurrence of matrices where seeds of those species could be collected. Bibliographic surveys in the specialized literature and research in the Herbarium Museu Botânico Municipal de Curitiba (MBM) and Herbarium of Universidade Estadual do Oeste do Paraná (UNOP) were conducted to identify potential species for degraded area recovery in the study of Western region of Paraná. In all, 115 species were selected, of which 22 are pioneer, 73 are secondary, and 20 are climactic. The bibliographic surveys suggests that pioneer species are the most indicated for the initial processes in the degraded areas recovery, while secondary and climactic species play a major role in area enrichment.

Evapotranspiration and crop coefficient of drip irrigated watermelon in Piaui coastline, Brazil

The knowledge of the evapotranspiration (ETc) and crop coefficient (Kc) is fundamental to plan and to manage the irrigation of any crop. The aim of this study was to determine the daily and hourly evapotranspiration of drip irrigated watermelon (Citrullus Lanatus, var. Crimson Sweet) and crop coefficient (Kc) in each crop development phase. The experiment was carried out in an experimental area of 1.27 ha of Embrapa Mid-North, localized in Parnaíba (02°54'S, 41°47'W and 46 m above of sea), State of Piauí, Brazil, from September to November, 2006. Electronic weighing lysimeters of 1.5 m x 1.5 m wide and long and 1.0 m deep were used to obtain the evapotranspiration. The plants were drip irrigated with a lateral row per plant row and drippers spaced 0.5 m from each other. The reference evapotranspiration (ETo) was estimated using the Penman-Monteith equation from the climatic data obtained by electronic sensors. The total evapotranspiration during the watermelon crop cycle cultivated in the state of Piauí was 233.87 mm, with mean values of 3.7 mm day-1, minimum of 1.18 and maximum of 8.14 mm day-1. The Kc of the drip irrigated watermelon was 0.18 in the initial stage of crop growth; 0.18 to 1.3, in crop development stage; 1.3 in the intermediate stage and 0.43 in the final stage.

Erosion factors and magnetic susceptibility in differet compartments of a slope in Gilbués-PI, Brazil

The erosion is the degradation of soil with effects on crop productivity and pollution of the environment. To understand the spatial variability of this phenomenon, geostatistical techniques and concepts of soil-landscape can be used to identify landscape compartments with different potential of erosion. The aim of this study was to understand the factors of erosion in landscape compartments and the relations with the magnetic susceptibility (MS) of the soils in a slope in Gilbués, state of Piauí (PI), Brazil. Sampling meshes were set in compartments I and II with 121 points and in compartment III with 99 points spaced every 10 meters. There was significant difference to erodibility (K) and risk of erosion (RE); the spatial variability of MS was lower than the factors of soil erosion. The soil losses (A), the natural erosion potential (NEP), the RE and the MS had spatial relation with the topographic factor, indicating dependence of the erosion with the relief. We concluded that losses of soil, natural erosion potential and risk of erosion have spatial relation with the topographic factor, showing the dependence of the erosion factors with the relief. The soil magnetic susceptibility can be used as an auxiliary variable in the indirect quantification of the erodibility factor and the risk of soil erosion.

Quality Indicators of Cervical Cytopathology Tests in the Public Service in Minas Gerais, Brazil

Objective The objective of this study is to assess the performance of cytopathology laboratories providing services to the Brazilian Unified Health System (Sistema Único de Saúde - SUS) in the State of Minas Gerais, Brazil. Methods This descriptive study uses data obtained from the Cervical Cancer Information System from January to December 2012. Three quality indicators were analyzed to assess the quality of cervical cytopathology tests: positivity index, percentage of atypical squamous cells (ASCs) in abnormal tests, and percentage of tests compatiblewith high-grade squamous intraepithelial lesions (HSILs). Laboratories were classified according to their production scale in tests per year≤5,000; from 5,001 to 10,000; from 10,001 to 15,000; and 15,001. Based on the collection of variables and the classification of laboratories according to production scale, we created and analyzed a database using Microsoft Office Excel 97-2003. Results In the Brazilian state of Minas Gerais, 146 laboratories provided services to the SUS in 2012 by performing a total of 1,277,018 cervical cytopathology tests. Half of these laboratories had production scales≤5,000 tests/year and accounted for 13.1% of all tests performed in the entire state; in turn, 13.7% of these laboratories presented production scales of > 15,001 tests/year and accounted for 49.2% of the total of tests performed in the entire state. The positivity indexes of most laboratories providing services to the SUS in 2012, regardless of production scale, were below or well below recommended limits. Of the 20 laboratories that performed more than 15,001 tests per year, only three presented percentages of tests compatible with HSILs above the lower limit recommended by the Brazilian Ministry of Health. Conclusion The majority of laboratories providing services to the SUS in Minas Gerais presented quality indicators outside the range recommended by the Brazilian Ministry of Health.

Ultrastructure of Babesia equi trophozoites isolated in Minas Gerais, Brazil

A transmission electron microscope study was carried out on Babesia equi obtained from a splenectomized horse, from the municipality of Santa Luzia, Minas Gerais, Brazil. The isolate was inoculated into two splenectomized foals (1.05 x 10(10) parasitized erythrocytes by B. equi). Trophozoites have a single membrane in direct contact with the cytoplasm of the red blood cells, a prominent nucleus, well-developed rough and smooth endoplasmic reticulum, numerous free ribosomes and small food vacuoles. B. equi trophozoites have a cytostome and a long tubular feeding structure in direct contact with the blood plasma.

Prevalence and geographical distribution of bovine eurytrematosis in cattle slaughtered in northern Paraná, Brazil

A retrospective study of cattle slaughtered in northern Paraná during 2000 was performed to determine the prevalence and geographical distribution of bovine eurytrematosis (BE), as identified by the Federal Inspection Service (SIF). The cattle was from different regions of the State of Paraná; all regions had cattle parasitized by Eurytrema spp. BE was identified in 12.1% (12,534/103,411) of the total number of cattle inspected. Prevalence of animals parasitized by Eurytrema spp varied from 8.3% (Region G, São João do Caiuá, 1,069/12,914) to 40.5% (Region R, Ponta Grossa, 225/555). BE was more prevalent during the month of March (1.6) and markedly reduced during May (-2). A possible seasonal predominance of BE was identified: comparatively fewer cases occurred from April to August, while there was a peak from December to March. The study indicates that bovine eurytrematosis is hypoendemic and occurs in almost all geographical regions of the State of Paraná. The prevalence within this State is variable and may be directly related to factors of the biological cycle of the trematode, particularities of each region, and environmental conditions.