Superfícies geomórficas e atributos do solo em uma toposseqüência de transição várzea-terra firme

Soil attributes reflect influence of the geomorphic surfaces. Therefore, the objective of this work was to investigate the influence of the geomorphic surfaces on soil attributes in a topossequence from low lands to high lands in the Humaitá region, AM. A transect of 4.5 km, from the top of the slope towards the low lands was established and the geomorphic surfaces were identified and limited according to topographic and estratigraphic criteria, based on detailed field investigation. Twenty soil samples were collected in each one of the slope segments within the geomorphic surfaces (G.S.), at the following depths: G.S. I: LAa (0.0-0.16 and 0.48-0.79 m); G.S. II: Lad1 (0.0-0.13 and 0.44-0.70) and Lad2 (0.0-0.10 and 0.30-0.55 m); G.S. III: RYve1 (0.0-0.18 and 0.51-0.89) and RYve2 (0.0-0.23 and 0.58-0.91 m). The sampling depths were determined by the surface and subsurface horizon depths, defined during the soil morphological description. Physical analysis involved particle size distribution, disperse clay, soil and particle density and total porosity. The chemical analysis involved determinations of pH in water and KCl, exchangeable cations, exchangeable Al, total acidity (H+Al), available P, organic carbon. The relief variations contributed to the presence of dystrophic soils in the geomorphic surface I and eutrophic soils in the geomorphic surface III. The multivariate statistical techniques were able to separate three heterogeneous groups, equivalent to the mapped geomorphic surfaces.

Densidade populacional de pratylenchus spp. em pastagens de brachiaria spp. e sua influência na disponibilidade e na qualidade da forragem

The aim of this work was to evaluate the population density of Pratylenchus brachyurus and Pratylenchus zeae associated with Brachiaria brizantha, B. decumbens and B. humidicola and their influence on forage availability and quality. The experiment was conducte in the Hisaeda Farm, Terenos, MS, Brazil. Soil, roots and plant aerial part were harvest with ten replications each, in one square meter randomized sets encompassing three treatments: Good, Intermediary and Bad, visually characterized, considering the percentage of green material. P. brachyurus and P. zeae density were evaluated in soil and plant roots. Dry matter of green, dead and re-growth materials, plant nutritional status and forage quality were assessed in the aerial plant part. Soil fertility was determined in all harvested samples. Both nematode species were identified from all samples, with a larger numbe in the roots (between 87-311 P. brachyurus and 1-61 P. zeae.10 g-1) than in the soil (0-8 P. brachyurus and 1-39 P. zeae.200 cm-3), however, no significant differences were found in the number of specimens between treatments. Considering that these forage species are perennial and host Pratylenchus spp, there is a tendency to increase the population of these pathogens over time, becoming a serious phytosanitary problem.

Densidade e época de semeadura de duas espécies de Brachiaria sobre a cultura da soja

The aim of this study was to evaluate the growth and yield of soybean cultivar M-8766 in consortium with Brachiaria brizantha. BRS Piata and Brachiaria ruziziensis at different densities and sowing dates. The experimental design was randomized blocks with treatments arranged in a factorial 2 × 2 × 3 with four replications. Used as factors grass species (Brachiaria brizantha Piata and Brachiaria ruziziensis BRS) intercropped with soybean M-8766, sowing dates (12 and 24 days after soybean emergence) and three seeding rates (0, 5, 10 kg ha-1 of seed). At 71 days after soybean emergence were evaluated plant height, stem diameter, dry mass of leaves, stems and shoots, and 4 months after sowing determined the weight of 100 grains and soybean yield. The results showed that when seeded at a density of 10 kg ha-1 at 12 and 24 DAE soy, Brachiaria brizantha. BRS Piata caused reduction in yield in the order of 6.71% and 3.03% respectively, while the Brachiaria ruziziensis was one that caused a greater reduction in productivity in the order of 13.42 and 16.23%, respectively, of these values expression when considering the price of soybean sack. B. ruziziensis expressed less competitive with soybean. However, the large biomass production of this grass provides deployment system till the next harvest.

Impactos sociais da crise econômica, políticas sociais e transição democratica

Incluye Bibliografía

Métodos não convencionais para avaliação da porosidade e da densidade do solo de um latossolo vermelho

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comportamento produtivo do trigo em função da densidade de semeadura e da aplicação de reguladores vegetais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da alimentação e densidade de estocagem no desempenho zootécnico e perfil celular do hepatopâncreas do camarão-da-amazônia Macrobrachium amazonicum (Heller, 1862) (Crustacea, Palaemonidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da densidade de estocagem na sobrevivência e crescimento do pampo (Trachinotus carolinus) em tanques-rede marinhos

Pós-graduação em Aquicultura - FCAV

Análise de parâmetros de força e padrão de nado de ratos controles e obesos, a partir de um sistema de aquisição de sinais em natação atada: Influência da intensidade do exercício e da densidade corporal

Pós-graduação em Ciências da Motricidade - IBRC

A influência do peso molecular do PEG na transição-Ψ multimolecular do DNA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diversidade e sazonalidade da acarofauna de Hymenaea martiana Hayne (Leguminosae) em gradiante de tamanho de plantas

Pós-graduação em Biologia Animal - IBILCE

Florística e fitossociologia do estrato arbustivo de área de transição savana-floresta no Parque Estadual de Porto Ferreira, SP

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Análise metaloproteômica de cálcio, ferro e zinco em colostro, leite de transição e leite maduro humanos

Pós-graduação em Biologia Geral e Aplicada - IBB

Avaliação da densidade microvascular em astrocitomas em adultos correlacionada com SPECT-MIBI

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Atributos químicos do solo, densidade de raiz e produtividade da cana-de-açúcar em função da aplicação de gesso agrícola

Pós-graduação em Agronomia (Ciência do Solo) - FCAV