Currently, an activity that has become strategic at a national level is the cultivation of oil palm (Elaeis guineensis) in the northeast region of the Pará State, in eastern Brazilian Amazon. However, the impacts of this crop expansion on the hydro-sedimentological cycle are still unknown. Therefore, this study estimated the impacts of oil palm crop expansion on sediment production in a sub-basin under consolidated use of this crop. The Soil and Water Assessment Tool (SWAT) model was applied in the Mariquita sub-basin, calibrated by the flow regionalization technique, using data measured in the field with a current meter. Simulation results indicated an increase in sediment production between the years 2008 and 2013, which can be attributed to the large reduction of areas of secondary vegetation that were replaced by pasture, oil palm and general agriculture. Oil palm areas had a lower average monthly sediment yield in the rainiest period in all simulated years, compared with areas of general agriculture and pasture.

Water availability is a crucial factor in the final productivity of cowpea. The objective of this work was to evaluate the production and productivity components of cowpea under different irrigation depths in Amazonian conditions. The experiment was carried out at the School Farm of the Federal Rural University of Amazonia, in the municipality of Castanhal-PA, using the cultivar BR3 Tracuateua, from September to November 2014, 2015, and 2016. The experimental design was conducted on six blocks and four treatments, where the four irrigation depths of 0, 25, 50, and 100% of crop evapotranspiration were tested. The productivity analysis was performed when 90% of the plants were in the phenological stage R9. The evaluated production components were pod length, number of pods per plant, number of grains per pod, mass of one hundred grains, and harvest index. There was a statistical difference among all treatments for the components of production and among productivities. An average reduction of 827 kg ha⁻¹ in cowpea productivity was observed during the three years of study, when the treatment without irrigation was compared with the treatment irrigated with 100% of the crop’s water demand. It was found in this research that the simple fulfillment of the nutritional and phytosanitary demands of the crop, associated with an adequate planning of when to plant in the region, would already help in the improvement of local production when choosing times where the water deficit in the reproductive phase is less than 33 mm.

Flow in the Capim River watershed, located in the state of Pará, Brazil, was estimated using the Soil and Water Assessment Tool (SWAT) model in order to determine its use efficiency. The meteorological data (from 2000 to 2010) were collected from an automatic station located in the municipality of Paragominas. The pluviometric and fluviometric data are available at the National Water Agency (ANA) website. Overall results show Efficiency Coefficient (Eff) values of 0.65 (for sub-basin 5) and 0.87 for the entire investigated period. The results also show a reduction in Eff estimation error, which started from over-estimation of 219.18% and declined to underestimation of 18% (in sub-basin 5). In summary, validation of the SWAT model was successful after adjusting the sensors during the calibration phase. Thereby, this model can be used in other studies evaluating river basins.

IMPACTOS DAS MUDANÇAS CLIMÁTICAS NA CULTURA DA SOJA NO NORDESTE DO ESTADO DO PARÁ - DOI: 10.7127/rbai.v12n200744

O clima na Amazônia vem se alterando, principalmente pelas atividades antrópicas. Uma floresta primária detém de 80% a 85% de floresta de terra firme, elevada diversidade e riqueza de espécies. Com o objetivo de caracterizar o clima da região de estudo, associando à variabilidade dos oceanos, atlântico e pacífico equatorial, com a chuva (chuvas), umidade e temperatura do ar, buscando uma visão espaço-temporal da evolução climática regional em um período pré-estabelecido, além de investigar a influencia destas variáveis climáticas na densidade populacional de mosquitos na região de floresta primária, onde as informações destas variáveis foram obtidas no site do INMET/BDMET e na Torre do LBA (meteorológicos) e no site da NOAA (índices de IOS/TSM) e as informações sobre a densidade dos mosquitos foram adquiridas no consorcio entre Museu Paraense Emilio Goeldi, FIOCRUZ, Instituto Evandro Chagas e Universidade Federal do Pará que realizaram a coleta de mosquitos dentro de uma unidade de conservação (UC) em cinco campanhas com duração de 6 dias cada, realizadas no período de junho, setembro e dezembro de 2005, e fevereiro e abril de 2006. A variabilidade e a evolução do clima para a área de estudo, apresentaram elevação em suas oscilações tanto da temperatura média do ar (de »0.28°C por década) quanto dos níveis de chuva com redução nos índices de umidade do ar, indicando que mesmo com o aumento das chuvas, a floresta sugere uma atmosfera com intervalos maiores de estiagem. Existe um indicativo de elevação expressiva nos níveis de temperatura média do ar (>1.5°C), e nos índices de chuvas, além de pouca e tendenciosa redução nos índices de umidade do ar, concorrendo para um aumento significativo na densidade de mosquitos com maior amplitude na distribuição das endemias na região.

Few research on the entomofauna associated to forest plantations with Swietenia macrophylla (King) in Brazil has been reported. The aim of this study was to analyze the Coleoptera communities in forest ecosystems with S. macrophylla, Brazilian mahogany, with emphasis on the diversity of families and the main functional groups. The insects were collected through pitfall traps in three forest ecosystems: monoculture, consortium and forest enriched with Brazilian mahogany, during dry and rainy periods in two consecutive years. The identification of the captured insects occurred in the entomology laboratory of the Federal Rural University of Amazonia. The analysis was performed through Past Paleontological Statistic 3.14 and ANAFAU, where the difference was considered significant only when p ? 0.05. 11,358 specimens from 21 families were captured, of which 8,058 were sampled in the rainy season and 3,299 in the dry season. There was influence of seasonality and types of forest ecosystems during collection. The families Nitidulidae, Staphylinidae, Carabidae and Meloidae presented greater abundance and richness in the complex ecosystems. Anobiidae, Cerambycidae, Bostrichidae, Brentidae, Buprestidae, Curculionidae, Elateridae, Chrysomelidae and Lagriidae were considered to be pests and common to all studied ecosystems; however, the families Nitidulidae, Scarabaeidae, Tenebrionidae and Passalidae had the function of decomposers; Carabidae, Coccinellidae, Histeridae, Meloidae, Staphylinidae, Cantharidae and Hydrophilidae were the predators.