Dinâmica de cátions na raiz e folhas de berinjela cultivada sobre doses crescentes de potássio oriundas de duas fontes

This study was conducted at the Department of Plant Production, Sector Horticulture, UNESP - Botucatu, SP, Brazil, in order to assess the dynamics of cationic nutrients in roots and leaves and effects on dry matter production of roots and shoots in eggplant grown on conditions of increasing doses of potassium from two distinct sources (KCl and K 2SO 4). The experiment was arranged in randomized blocks in factorial 2 × 4 (two sources of potassium, KCl and K 2SO 4 and four doses of each source equivalent, 250, 500, 750 and 1000 kg ha -1 K 2O) comprising eight treatments with three replicates. For the experiment we used Oxisol medium texture (615 g of sand, silt 45 g and 340 g clay per kg soil). The characteristics evaluated were: soil electrical conductivity, mass of shoot and root material, content and ratio of K +, Ca 2+ and Mg 2+ in roots and leaves of eggplant. We conclude that excessive doses of sources of K 2O affected the production of dry matter of roots and shoots, as well as electrical conductivity. The accumulation and the relationship of Ca2+/K+, Mg 2+/K + were affected by increased K + concentration; K 2SO 4 was the fertilizer that was less damaging.

Sponge spicules indicate Holocene environmental changes on the Nabileque River floodplain, southern Pantanal, Brazil

Sponge spicules are siliceous microfossils that are especially useful for analysis of sandy fluvio-lacustrine sediments. Sponge spicules in a long sediment core (~550 cm below surface), consisting of fine sand, sandy silt, and organic-rich mud, recovered from the floodplain of the Nabileque River, southern Pantanal, Brazil (S20°16′38. 3″/W57°33′00. 0″), form the basis of a novel paleoenvironmental interpretation for this region. Optically stimulated luminescence dates constrain the timing of deposition to the middle-late Holocene and all spicules identified are typical of the Brazilian cerrado biome. The base of the section is dominated by Oncosclera navicella Carter 1881, Metaniaspinata Carter 1881, and Corvospongilla seckti Bonetto and Ezcurra de Drago 1966, which indicate a lotic to semi-lotic environment strongly influenced by an actively meandering river channel at ~6. 7-5. 7 ka BP. The appearance of Heterorotula fistula Volkmer-Ribeiro and Motta 1995, Dosilia pydanieli Volkmer-Ribeiro 1992 and Radiospongilla amazonensis Volkmer-Ribeiro and Maciel 1983 at ~340 cm downcore suggests a reduction in flowing water and a more stable lentic environment, consistent with deposition in an oxbow lake. This oxbow lake environment existed during an interval of regional aridity between ~4. 5 and 3. 9 ka BP. Spicules, as well as phytoliths and diatoms, are highly variable moving up-section, with species from both lotic and lentic ecosystems present. Above ~193 cm, the total abundance of spicules declines, consistent with wetter climate conditions and development of an underfit river similar to the modern floodplain. Results support hypotheses related to migration of the Paraguay River inferred from geomorphological studies and add a key southern-region dataset to the emerging Holocene database of paleoenvironmental records from the Pantanal wetlands. © 2012 Springer Science+Business Media Dordrecht.

Variabilidade espacial de atributos físicos em um cambissolo háplico, sob diferentes usos na região sul do Amazonas

Considering the importance of knowledge of the spatial distribution of soil properties, the purpose of this study was to evaluate the spatial variability of physical properties in a Cambisolunder different land uses in the southern Amazon region. The study was conducted on three farms with cassava, sugarcane, and agroforestry, in the region of Humaitá, in the south of the State of Amazonas. In these areas, 70 x 70 m grids were established, with a regular spacing of 10 x 10 m and a total of 64 points, where soils were sampled at 0.0-0.10 m depth. Texture (sand, silt, and clay), macroporosity, microporosity, total porosity, bulk density, and aggregate stabilitywere determined. The data were analyzed using descriptive statistics and geostatistics. It was found that the propertiesvaried spatially and that the range of these variations between land uses was different, with the highest variability for the sugarcane management.

Crescimento radicular e nutrição mineral de cultivares de feijão em resposta à calagem

Pós-graduação em Agronomia (Agricultura) - FCA

Caracterização da fertilidade do solo da composição mineral de espécies arbóreas de restinga do litoral paulista

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variabilidade espacial de atributos do solo em áreas intensamente cultivadas nas regiões de Jaboticabal e Monte Alto - SP

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

Encapsulamento do cromo proveniente do lodo de curtume, em matrizes de cimento, visando a resistência mecânica à compressão e os limites de lixiviação e solubilização

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Análise do aproveitamento energético do biogás produzido numa estação de tratamento de esgoto

Pós-graduação em Engenharia Mecânica - FEIS

Zoneamento geotécnico do sítio urbano do município de Rio Branco/AC e seus arredores, para fins de planejamento com ênfase à expansão urbana, através do sensoriamento remoto

Pós-graduação em Geociências e Meio Ambiente - IGCE

Avaliação do processo de infiltração da água em solo residual de Biotita-gnaisse para superfícies com diferentes declividades utilizando lisímetros

Pós-graduação em Engenharia Civil e Ambiental - FEB

Uso de lodo de estações de tratamento de água e de esgoto urbano como condicionador de solo, com ênfase nas propriedades físicas do solo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reação de cultivares de alface do grupo americano a Meloidogyne incognita, M. javanica e M. enterolobii

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Temperatura e atributos físico-químicos de um latossolo em recuperação com adubação verde, gramínea e lodo de esgoto, cultivado com Gonçalo-Alves

Pós-graduação em Agronomia - FEIS

Inter-relações da variabilidade espacial da granulometria do solo e a produtividade do feijoeiro sob plantio direto

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Correlação linear e espacial da produtividade de forragem de milho com atributos físicos de um latossolo vermelho distrófico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)