Soil Mapping in the Pantanal of Mato Grosso, Brazil, using Multitemporal Landsat TM data

Keywords Multitemporal data sets from the Landsat Thematic Mapper (TM) were used to evaluate their applicability for exploratory soil mapping in the floodplain of the Northern Pantanal of Mato Grosso, Brazil. Fifty-four soil profiles were classified into 21 soil units according to the FAO–UNESCO system. Information layers of vegetation types and dynamics of flooding were elaborated by applying supervised hierarchical classification rules. Geomorphologic units were mapped by visual image interpretation. Multinomial logistic regression was applied to test relations between thematic layers and soil units as well as aggregated soil clusters, developing a statistical mapping model. Northern Pantanal floodplain soils show a high variability as a function of age and granulemetry of underlying sediments, as well as soil moisture and flooding regimes. GIS layers of nine vegetation formations, three geomorphologic units and three multi-temporal moisture types were elaborated. Cross-tabulations and multinomial logistic regression models indicate significant relations between FAO–UNESCO soil units and GIS layers. As soil sampling density had been low, a final predictive model was developed for the mapping of six aggregated soil clusters, obtaining a high significance level (p<0.05) for prediction. Applied methodology was found to be appropriate to develop models on soil–landscape relationships and improve information on spatial distribution of soil groupings in the Northern Pantanal.     

Intestinal parasites in Iaualapiti Indians from Xingu Park, Mato Grosso, Brazil.

Brine flotation and gravity sedimentation coproscopical examinations were performed in stool samples from 69 of the 147 Iaualapiti Indians of the Xingu Park, Mato Grosso State, Brazil. Intestinal parasites were present in 89.9% of the population examined. High rates of prevalence were found for some parasite species: Ancylostomidae, 82.6%; Enterobius vermicularis, 26.1%; Ascaris lumbricoides, 20.3%; and Entamoeba coli, 68.1%. Infection by Trichuris trichiura, Schistosoma mansoni, Taenia spp. and Hymenolepis nana was not detected. Helminth's prevalence in children aged one year or less was comparatively low (33.3%). Quantitative coproscopy was done in positive samples for Ascaris and Ancylostomidae and the results expressed in eggs per gram of feces (EPG). Quantitative results revealed that worm burdens are very low and overdispersed in this Indian tribe, a previously unreported fact.     

Prevalence of hepatitis E virus antibodies in individuals exposed to swine in Mato Grosso, Brazil

This study was conducted to estimate the prevalence of hepatitis E antibodies (anti-HEV) among individuals exposed to swine in the rural areas of the state of Mato Grosso (MT) in Brazil. The study included 310 participants who had an average age of 39 years. Fifty-one per cent of the participants were female and 26 (8.4%) were anti-HEV-positive. Concomitantly, we studied 101 blood donors from the urban area of the state capital who had never lived in a rural area or handled swine. Four per cent (4%) of these individuals were anti-HEV-positive (p = 0.206). When we compared the anti-HEV-positive participants who had been exposed to swine with the anti-HEV-negative participants, we noticed associations between the presence of anti-HEV and increased age, a history of blood transfusions and contact with other farm animals. However, after a multivariate analysis was performed, this association was not confirmed. Finally, the ratio of anti-HEV-positive individuals who had been exposed to swine in rural MT was similar to that found in previous studies in Brazil. This prevalence did not characterise this type of exposure as a risk factor for HEV infection in this region.     

Zooplankton in the Floodplains of a Tributary to the Paraná River in Mato Grosso Do Sul,Brazil

Zooplankton samples were taken monthly at five sites March 1992 through February 1993 of the Guaraná lake and Baía river in the Paran floodplain, Brazil. A total of 38 cladoceran and 12 copepod species was identified. Cladocerans were mainly collected amongst macrophytes in the lake. The most commonly encountered species were Bosminopsis deitersi, Moina minuta, Ceriodaphnia cornuta, Ilyocryptus spinifer, Macrothrix spinosa, and Phryxura dadayi. The copepods were especially collected in the river with Thermocyclops minutus and Mesocyclops meridianus being abundant. The greatest number of microcrustacean species was detected during the high water period. Possible ecological conditions for the recorded distribution and abundance are discussed and compared with data from other study sites in the Neotropics.     

Mucormycosis in Mato Grosso, Brazil: A Case Reports, Caused by Rhizopus microsporus var. oligosporus and Rhizopus microsporus var. rhizopodiformis

We identified the etiological agents responsible for two fatal cases of rhinocerebral mucormycosis with the classical risk factor for uncontrolled type II diabetes mellitus. Their initial symptoms did not point immediately to the suspicion of mucormycosis. Case 1, caused by Rhizopus microsporus var. oligosporus, was a 52-year-old man who presented with a painful pimple on his nose, which evolved with swelling, erythema, and a central pustule on his right hemiface suspected to be cellulitis. After 7 days of antibiotic treatment, the patient worsened with signs of sepsis and the lesion evolved to necrosis involving all his right face. Case 2, caused by Rhizopus microsporus var. rhizopodiformis, was a 57-year-old woman placed on continuous therapy with azathioprine and corticoids after a renal transplant due to chronic arterial hypertension and uncontrolled type II diabetes mellitus. Because she was suspected to have sepsis, the patient was treated with broad-spectrum antibiotics and mechanical ventilation, yet she deteriorated. Because Candida spp. were isolated from urine and a BAL, she was treated with fluconazole for 10 days, then substituted by caspofungin. Two weeks later, she presented with exophthalmus of the left eye that was surrounded by a large inflammatory and necrotic area. Both patients were the diagnosed with mucormycosis via direct microscopy of necrotic material prior to their death.     

A new species of Discocyrtanus from Mato Grosso,Brazil (Opiliones: Gonyleptidae) with a key to the species of the genus

Discocyrtanus canjinjim sp. n., belonging to the family Gonyleptidae Sundevall, 1833 is described based on nineteen specimens, eleven adult males and eight adult females, collected in the Vila Bela da Santíssima Trindade, in the State of Mato Grosso, Brazil. This new species represents an endemic component for the harvestmen fauna of Chiquitano Dry Forests terrestrial eco-region, being the most occidental point of distribution of the genus, notably found in the Cerrado and the Atlantic Forest. The new species is characterized by femur IV swollen with the same length of dorsal scutum, trochanter IV with prodorsal distal apophysis as a stout hook not bifurcated, and a unique form of genitalia in the genus. This paper also includes the first identification key to the species of the genus after its revalidation.     

Yield per recruit of the pacu Piaractus mesopotamicus (Holmberg, 1887) in the pantanal of Mato Grosso do Sul, Brazil.

Among the several fish species comercially exploited at the Pantanal of Mato Grosso do Sul, the "pacu" (Piaractus mesopotamicus) stands as one of the most important. Information regarding its exploitation level is necessary for the proper management of its stocks. Between 1996 and 1997 data on total length of the pacu were collected on a monthly basis from specimens caught by professional and sport fishers in the municipality of Corumbá. These data were used to estimate growth parameters and to assess the exploitation level for this species, applying the Beverton and Holt yield per recruit model. Length frequency analysis, carried out with the software FISAT (ELEFAN), was used to estimate growth parameters: 1996: L(infinity) = 87.20 cm; K = 0.34 year(-1); phi(')=3.41; C = 0.74; WP = 0.81; Longevity = 8.40 years; and 1997: L(infinity) = 86.50 cm; K = 0.34 year(-1); phi(')=3.40; C = 0.60; WP = 0.80; Longevity = 8.40 years. The value for t(0) is -0.363 years for mean values of L(infinity) and k. The weight-length relationship, calculated from data derived from experimental fisheries carried out in 1999 and 2000, is described by the equation: W = 0.048LF(2.835). Estimated mortalities and survival rates were: 1996: Z = 1.51 year(-1); M = 0.62 year(-1); F = 0.89 year(-1); S = 21.9%; and 1997: Z = 1.65 year(-1); M = 0.63 year(-1); F = 1.02 year(-1); S = 19.1%. The yield per recruit analysis showed the following values: F(Present) = 0.96 year(-1); F(max) = 0.67 year(-1) ; F(0.1) = 0.51 year(-1) (for L(c) = 26.7 cm). These results suggest that the pacu is overexploited in the area, so that restrictive measures are in need to manage the pacu fisheries.     

A new sand fly, Lutzomyia campograndensis sp. n. (Diptera: Psychodidae: Phlebotominae) from the State of Mato Grosso do Sul, Brazil

During studies of the phlebotomine sand fly fauna of Campo Grande, State of Mato Grosso do Sul, Brazil, a new species was captured with CDC light trap and is described here. The new species resembles Lutzomyia lutziana (Costa Lima) and is named Lutzomyia campograndensis sp. n. after the type locality.     

Hook selectivity of the pacu Piaractus mesopotamicus (Holmberg, 1887) in the Pantanal, the state of Mato Grosso do Sul, Brazil.

The Pacu Piaractus mesopotamicus is the most captured fish species in the Pantanal, Mato Grosso do Sul State, and since 1994, its maximum sustainable yield had already been exceeded. Its capture is carried out only by hooks, as mesh gears are forbidden either for professional or for recreational fishing. The aim of this study was to determine selectivity for different hook sizes used in P. mesopotamicus fishing and to verify which sizes capture only adults. Data were collected in the rivers Miranda, Aquidauana, and Vermelho, in January, March, and April 2002. Six longlines with eight hook sizes were used and we adopted the hook opening as a measure related to selectivity. Different hooks captured individuals of the same length and their medians were similar, evidencing the great overlap among sizes. Regression results showed no significant relationship between ln[c2(l)/c1(l)] and total length of captured individuals. In addition, the Kolmogorov-Smirnov test also did not detect significant differences in the size of captured fish. Several hypotheses, such as the selectivity models, shape of selection curves, scarcity of large fishes, and behavior are used in order to explain the absence of hook selectivity for this species. Size of recruitment for this gear was 28 cm of total length, when individuals are still immature.     

Morphologic analysis of the venom gland of Apis mellifera L. (Hymenoptera: Apidae) in populations of Mato Grosso do Sul, Brazil

In Apis mellifera L. the venom gland (also called acid gland) is composed of secretory cells that surround a channel that opens into a reservoir devoid of musculature. This gland can present apical branching. In this study the frequency of branched venom glands in Africanized honeybee workers (A. mellifera) from eleven localities in the state of Mato Grosso do Sul was recorded. The relations among the length of the main duct, the length of the duct from the reservoir to the beginning of branching, the length of the branched segment (when present) and the total length of the gland were also analyzed. The frequency of branched glands varied from 50% to 83% in the workers, indicating that this characteristic is primitive in those bees. The results of the Analysis of Discriminant Functions indicated significant differences in the morphometrical segments of the venom gland (Wilks Lambda = 0.092; F (40, 55) = 3.43; P < 0.001), and permitted a differentiation of the populations studied. Using the Mantel test we verified that there does not exist a significant correlation between the morphologic characteristics and the geographical distance between the localities evaluated (Mantel r = -0.006, P = 0.48). The high frequency of workers with large venom gland in all the apiaries considered makes viable the development of a selection program in order to obtain bees with longer venom glands, aimed at the commercial production of venom by the beekeepers of those localities of Mato Grosso do Sul.     

The Seasonal Succession of Biotic Communities in Wetlands of the Tropical Wet-and-Dry Climatic Zone: V. Aquatic Invertebrate Communities in the Pantanal of Mato Grosso,Brazil

The results of a 3 1/2 year study in the Pantanal of Mato Grosso revealed that the life cycles of the invertebrates are profoundly influenced by the annual alternations between a period of very heavy rainfall and several months during which almost no rain falls. A very pronounced effect on the biota is the elimination of many species present in neighboring regions but without the ability to survive periods of adverse conditions resulting from the alternations between flood and dryness. However, those species with suitable adaptations are able to produce very large populations. The annual activity cycles of the invertebrates must not only be timed to the seasonal weather conditions but also to the activities of other species in the food web. They must be adapted to periods of surplus alternating with scarcity of food and predator pressure, which exert great influence on the development of the populations. Of the 256 species considered, most have the ability to produce offspring throughout the year whenever conditions are conducive, but there are also a considerable number which have life cycles apparently including only one reproductive period each year. The general effect of the seasonal changes on the aquatic community of the wetland is to greatly reduce species diversity but to allow the production of vast numbers of those species that have successfully adapted to the conditions. This adaptation of the aquatic species usually entails a dormant stage or a terrestrial one as well as a considerable rate of reproduction to offset losses during periods of unfavorable conditions. The invertebrate fauna includes several taxa represented overwhelmingly by cosmopolitan and circumtropical species, including Rotifera and Gastrotricha, but the great majority of the species are endemic to South America.     

The Seasonal Succession of Biotic Communities in Wetlands of the Tropical Wet-and-Dry Climatic Zone: II. The Aquatic Macrophyte Vegetation in the Pantanal of Mato Grosso,Brazil.

The seasonal succession of macrophyte communities on temporarily flooded wetlands in the Pantanal of Poconé was investigated by general surveys of the region and by semi-quantitative surveys conducted on an area of 2500 m² with a gradient of water depth steep enough to permit a correlation of the species diversity with the depth and duration of flooding. The tropical wet-and-dry climate is the main determinant of the regional ecological conditions, and the seasonal variations of the physical and chemical factors, including the alternation between aquatic and terrestrial conditions over most of the area, produce a pronounced seasonal succession. During all of the seasons, the occurrence and growth of the plant species on the area surveyed was found to be inversely correlated with the water depth, but the statistical significance of the findings varied during the course of the year. The plant species are discussed individually, since little or nothing had previously been reported about the autecology of several of them. In addition, a general survey is made of the common aquatic and wetland plant species encountered in the region. On sites temporarily inundated during the course of the year, there is usually a succession of vegetation involving purely terrestrial and aquatic species as well as short-lived annuals that appear only during the transition period from wet to dry and perennials with seasonal periods of dormancy during periods of excessive dryness.     

Occurrence of Antibodies to <Emphasis Type="Italic">Paracoccidioides brasiliensis</Emphasis> in Dairy Cattle from Mato Grosso do Sul,Brazil

The aim of this study was to evaluate the humoral immune response in cattle immunized with Paracoccidioides brasiliensis and perform a seroepidemiological study of paracoccidioidomycosis in dairy cattle from Mato Grosso do Sul. Two animals (one steer and one heifer) were inoculated with a suspension of P. brasiliensis in Freund incomplete adjuvant. Blood samples were collected periodically to evaluate humoral immune response by immunodiffusion and ELISA, using exoantigen and gp43 as antigens, respectively. The antibody production was detected by immunodiffusion and ELISA, in both animals, 14 days after immunization. The soroepidemiologic study was carried out in 400 cattle of Mato Grosso do Sul from four municipalities: Corumbá, Dourados, Nova Andradina, and São Gabriel d’Oeste. The municipalities of Corumbá (30%) and Nova Andradina (28%) showed higher positivity than Dourados (8%) and São Gabriel d’Oeste (4%). In this study we concluded that cattle immunized with P. brasiliensis develop humoral immune response for gp43, remaining with high titers of antibodies, and that this animal species could be an epidemiologic marker of paracoccidioidomycosis.     

Search for Borrelia sp. in ticks collected from potential reservoirs in an urban forest reserve in the State of Mato Grosso do Sul,Brazil: a short report

A total of 128 ticks of the genus Amblyomma were recovered from 5 marsupials (Didelphis albiventris) - with 4 recaptures - and 17 rodents (16 Bolomys lasiurus and 1 Rattus norvegicus) captured in an urban forest reserve in Campo Grande, State of Mato Grosso do Sul, Brazil. Of the ticks collected, 95 (78.9%) were in larval form and 22 (21.1%) were nymphs; the only adult (0.8%) was identified as A. cajennense. Viewed under dark-field microscopy in the fourth month after seeding, 9 cultures prepared from spleens and livers of the rodents, blood of the marsupials, and macerates of Amblyomma sp. nymphs revealed spiral-shaped, spirochete-like structures resembling those of Borrelia sp. Some of them showed little motility, while others were non-motile. No such structures could be found either in positive Giemsa-stained culture smears or under electron microscopy. No PCR amplification of DNA from those cultures could be obtained by employing Leptospira sp., B. burgdorferi, and Borrelia sp. primers. These aspects suggest that the spirochete-like structures found in this study do not fit into the genera Borrelia or Leptospira, requiring instead to be isolated for proper identification.     

The Seasonal Succession of Biotic Communities in Wetlands of the Tropical Wet-and-Dry Climatic Zone: IV. The Free-Living Sarcodines and Ciliates of the Pantanal of Mato Grosso,Brazil

This fourth paper in a series on the effects of the wet-and-dry climate on the northern Pantanal, Mato Grosso, Brazil, provides an outline of the seasonal activity of sarcodine and ciliate species. Both of these groups of protozoans include grazers on bacteria and algae, predators, and omnivores. Apparently because of their more complex trophic relationships and competition from small metazoans, the fauna of these groups in the Pantanal is considerably less rich in species than the alga flora, and the populations of most species remain small throughout the year. The presence of only 97 species was recorded during a period of study lasting about three and a half years. While the number of testacean species encountered is not notably less than expected, the number and diversity of the ciliate fauna are remarkably low compared to those encountered not only in the eutrophic waters of the temperate zones but also in water bodies in the eastern part of Brazil. The species found are almost exclusively cosmopolitan or circumtropical in distribution.     

A new sexually dichromatic miniature Hyphessobrycon (Teleostei: Characiformes: Characidae) from the Rio Formiga,upper Rio Juruena basin,Mato Grosso,Brazil, with a review of sexual dichromatism in Characiformes

Hyphessobrycon myrmex sp. nov., is described from the Rio Formiga, upper Rio Juruena, upper Rio Tapajós basin, Mato Grosso, Brazil. The new species can be distinguished from congeners by having the lower half of the body deeply pigmented with dark chromatophores, chromatophores concentrated above the anal fin and forming a broad, diffuse, dark midlateral stripe and by having a dense concentration of dark chromatophores along unbranched dorsal‐fin rays and distal portions of the two or three subsequent branched rays. In life, H. myrmex exhibits a conspicuous sexual dichromatism, with adult males red to orange and females and immatures pale yellow. A list containing 108 sexually dichromatic taxa in six families of Characiformes is provided and the distribution of this poorly known type of dimorphism across the Characiformes is discussed.     

The Seasonal Succession of Biotic Communities in Wetlands of the Tropical Wet-and-Dry Climatic Zone: I. Physical and Chemical Causes and Biological Effects in the Pantanal of Mato Grosso,Brazil

The tropical wet-and-dry climatic zone is characterized by aquatic environments that cover extensive areas during part of the year and shrink to small standing water bodies or rivers with minimal water levels during the dry seasons. Even in the small permanent water bodies, the conditions fluctuate radically during each annual cycle. While there are often strong currents in the water courses during the high water periods, most aquatic habitats are strictly lentic during the dry seasons. Studies conducted in the Pantanal of Mato Grosso, one of the largest wetlands of the world, revealed major features of changes in physical and chemical parameters during the annual cycle. The general features of the climate include a hot, rainy period usually lasting from late October through late April, a cool, dry period from late April through late August, and a hot, dry period from late August through late October. Considerable year to year variations are encountered in the dates of onset and end of the various seasons, however. Four annual periods are recognized according to the water level in the Pantanal. Generally, the concentrations of dissolved inorganic substances are very low and stable during the high water period and variable and usually high in the remaining standing water bodies when much of the region has dried out. The amount of mineral nutrients increases as the water level rises during the early rainy season but decreases again as the aquatic macrophyte populations develop. Some of the reasons for the many short-term changes in mineral nutrient concentrations and the roles of the various aquatic communities are discussed. The results presented will serve as a basis for subsequent studies on the seasonal succession of the flora and fauna.     

Using forest inventory data to predict winter habitat use by fisherMartes pennanti in British Columbia, Canada

This study assessed the possibility of predicting the distribution of potential winter habitats for fisherMartes pennanti Erxleben, 1777 in central interior British Columbia (BC) with the BC Vegetation Resources Inventory (VRI) dataset used to produce forestry maps. I predicted that fisher winter habitat would correspond to coniferous or coniferous-deciduous stands with the following characteristics: (1) absence of disturbance, (2) >- 80 years old, (3) mature and old forest structural stages, (4) ≥ 20 m²·ha^-1 basal area in mature trees, (5) ≥ 30% canopy closure, (6) shrub cover ≥ 20%, and (7) diameter at breast height ≥ 27.5 cm. I allocated weight values to these criteria to classify map polygons into excellent-, high-, medium-, and low- quality habitats, and produce predictive maps of winter habitat use by fishers. I tested predictive maps in the field by snow-tracking along 27 transects (44.2 km) in winter 2003–2004, and 16 transects (31.4 km) in winter 2004–2005. A total of 89 tracks were recorded during both years. The proportion of fisher tracks within each polygon type was significantly different from random (p < 0.001). The majority of tracks (> 83%) were in structurally complex coniferous stands. This study showed that it is possible to predict the distribution of potential winter habitats for fisher in central interior British Columbia using simple habitat criteria and the VRI dataset. This study’s query may be used in other regions with similar vegetation composition to identify forests be inhabited by fishers in winter, and develop effective conservation programs in managed landscapes.