Universidade Federal de Mato Grosso

About: Universidade Federal de Mato Grosso is a education organization based out in Cuiabá, Brazil. It is known for research contribution in the topics: Population & Species richness. The organization has 7748 authors who have published 10181 publications receiving 89994 citations.

Spatial and temporal distribution of fish larvae in marginal lagoons of Pantanal, Mato Grosso State, Brazil

Abstract: An analysis was made of the spatial and temporal distribution of the abundance and composition of fish larvae assemblies, aiming to ascertain correlations with biotic and abiotic factors in marginal lagoons of the Cuiaba River floodplain in Brazil's Pantanal wetlands. Samples were collected bimonthly in the pelagic region of the marginal lagoons (fourteen lagoons) close to the littoral zone covered by aquatic macrophytes from December 2006 to April 2007. The captured individuals consisted of 2,739 larvae, represented predominantly by Triportheus spp. (Characidae), Parodontidae, Anostomidae, Characidae and Serrasalmidae. Larval density varied among the sample lagoons in December, but the biotic (zooplankton density) and abiotic (water temperature, electrical conductivity, dissolved oxygen, pH, water transparency and lagoon depth) factors did not significantly affect larval composition and abundance. Larvae were captured throughout the sample period, with the highest densities occurring in December and early January. Temporally, lagoon depth, water transparency and fluviometric level showed a negative correlation with larval density. Both the zooplankton and the larval density vary positively, responding likewise to the environmental conditions imposed by flooding. The highest larval density was also found to coincide with the first rains (early December), when the rainfall has not yet reached its peak.

Geostatistical analysis of the spatial variation of the berry borer and leaf miner in a coffee agroecosystem

Abstract: The advent of geostatistics and geographical information systems has made it possible to analyze complex spatial patterns of ecological phenomena over large areas in applied insect ecology and pest management. The objective of this study was to use geostatistics to characterize the spatial structure and map the spatial variation of damage caused by the berry borer (Hypothenemus hampei) and leaf miner (Leucoptera coffeella) in a coffee agroecosystem planted with the cultivar Catuai Vermelho IAC-99. Infestations of berry borer and leaf miner were evaluated in fruits and leaves, respectively. The pests were monitored at 67 georeferenced points in an area of 6.6 ha in 2005, 2006 and 2007. Variograms estimated by the method of moments (MoM) and residual maximum likelihood REML were compared. The latter were generally better in terms of the kriging error coefficients. Spherical variograms estimated by REML for berry borer infestation in fruits had ranges of spatial dependence of 34.62–118.4 m and for the leaf miner they were 53.93–133.7 m. For models fitted by weighted ordinary least squares (OLS) to the MoM experimental variogram, the ranges varied between 37.22 and 68.67 m for the berry borer and 100 and 155.4 m for leaf miner infestation. The variogram model parameters were used with the data for ordinary kriging to map the spatial variation of coffee pests for different monitoring periods. If there was no suitable variogram, inverse distance weighting was used to map the variation. The maps enabled visualization of the intensity of infestation of the insect pests for the different periods evaluated.

Ocorrência de Pratylenchus brachyurus e Meloidogyne incognita na cultura do algodoeiro no Estado do Mato Grosso

Abstract: In a survey carried out in the state of Mato Grosso, Brazil, the lesion nematode, Pratylenchus brachyurus, and the root-knot nematode, Meloidogyne incognita, were found, respectively, in 94% and 3.7% of a total of 623 root and soil samples representing 21,793 ha. No visible aboveground symptoms in cotton (Gossypium hirsutum) plants infected by P. brachyurus were observed, except for typical root lesions. In contrast, plants with M. incognita usually exhibited pronounced symptoms of damage. The high frequency (94%) of P. brachyurus was unexpected and is of concern considering the fact that soybean (Glycine max) and corn (Zea mays), are both susceptible to this nematode and are used in crop rotation programs.

Probability sampling design in ethnobotanical surveys of medicinal plants

Abstract: Non-probability sampling design can be used in ethnobotanical surveys of medicinal plants. However, this method does not allow statistical inferences to be made from the data generated. The aim of this paper is to present a probability sampling design that is applicable in ethnobotanical studies of medicinal plants. The sampling design employed in the research titled "Ethnobotanical knowledge of medicinal plants used by traditional communities of Nossa Senhora Aparecida do Chumbo district (NSACD), Pocone, Mato Grosso, Brazil" was used as a case study. Probability sampling methods (simple random and stratified sampling) were used in this study. In order to determine the sample size, the following data were considered: population size (N) of 1179 families; confidence coefficient, 95%; sample error (d), 0.05; and a proportion (p), 0.5. The application of this sampling method resulted in a sample size (n) of at least 290 families in the district. The present study concludes that probability sampling methods necessarily have to be employed in ethnobotanical studies of medicinal plants, particularly where statistical inferences have to be made using data obtained. This can be achieved by applying different existing probability sampling methods, or better still, a combination of such methods.