3312 results

Soil chemical properties under different uses in an irrigated area in the semi arid region of Pernambuco, Brazil

Rossini Mattos Corrêa, Maria Betânia Galvão dos Santos Freire, Rinaldo Luiz Caraciolo Ferreira, Fernando José Freire, Luiz Guilherme Medeiros Pessoa, Marcelo Alves Miranda, [...]

01/Apr/2009

Soils developed at semi-arid climate can present salt accumulation, which compromise the agricultural use, being increased by inadequate irrigation management. Based on the use, the degradation of these soils can occur at higher or smaller intensity. This study aimed to evaluate the effect of soil uses based on physical and chemical properties of an irrigated area in the semi-arid region of northeastern Brazil. The soil uses were annual crops (C), fruticulture (F), pasture (P), discarded lands (D), or native vegetation […]

Potential and net nitrogen mineralization in soils

Renato Yagi, Manoel Evaristo Ferreira, Mara Cristina Pessôa da Cruz, José Carlos Barbosa

01/Apr/2009

The soil incubation methods can be used as tools to a better evaluation of N mineralization and availability. The objective of this study was to evaluate the potential and net soil organic N mineralization, and relate them to N availability to plants. Twenty two soil samples (0-20 cm) were incubated at 35 ºC for 30 weeks in aerobic conditions and at 40 ºC for seven days in anaerobic conditions, and tested in a greenhouse experiment on corn plants. During the 30 weeks-incubation period […]

Carbon dioxide efflux in a rhodic hapludox as affected by tillage systems in southern Brazil

Luis Fernando Chavez, Telmo Jorge Carneiro Amado, Cimélio Bayer, Newton Junior La Scala, Luisa Fernanda Escobar, Jackson Ernani Fiorin, [...]

01/Apr/2009

Agricultural soils can act as a source or sink of atmospheric C, according to the soil management. This long-term experiment (22 years) was evaluated during 30 days in autumn, to quantify the effect of tillage systems (conventional tillage-CT and no-till-NT) on the soil CO2-C flux in a Rhodic Hapludox in Rio Grande do Sul State, Southern Brazil. A closed-dynamic system (Flux Chamber 6400-09, Licor) and a static system (alkali absorption) were used to measure soil CO2-C flux immediately after soybean harvest. Soil […]

Genesis of the sombric horizon in ultisols (red argisols) in southern Santa Catarina, Brazil

Jaime Antonio de Almeida, Denis Cesar Cararo, Antônio Ayrton Auzani Uberti

01/Apr/2009

Dark subsurface horizons, with properties similar to the sombric horizon characterized by the USA Soil Taxonomy, are frequent in Southern Brazil. The genesis of this horizon is controversial and poorly understood. This study aimed to describe the occurrence of sombric-like horizons in Ultisols in the South of Santa Catarina State, at low altitudes, and suggest possible processes of humus transference, accumulation and persistence in these horizons. Physical, chemical and mineralogical properties of four Ultisols were evaluated; three were sampled in […]

Soil availability, nutritional status and sulfur recommendation for flooded rice

Felipe de Campos Carmona, Osmar Conte, Thiago Isquierdo Fraga, Thiago Barros, Edward Pulver, Ibanor Anghinoni

01/Apr/2009

The Depressão Central region in the State of Rio Grande do Sul, Brazil, is characterized by large areas of sandy soil that were intensively cultivated with flooded rice in the last decades. Currently, the high rice yields, along with the low organic matter content of these soils and the fertilization practices are favorable conditions for the appearance of sulfur (S) deficiency. With the purpose of determining sulfur distribution in the soil profile and recommending levels of this element for flooded […]

Soil nitrogen stock and availability in a long-term experiment

Mirla Andrade Weber, João Mielniczuk

01/Apr/2009

Nitrogen is the nutrient required in the largest quantity by plants and is generally the most limiting nutrient for crop yield. The objective of this research was to evaluate the effect of cropping systems on N accumulation and availability in the soil. A long-term experiment (22 years) was conducted on a Paleudult soil at an experimental station of the Federal University of Rio Grande do Sul (30 º 50 ‘ 52 ” S and 51 º 38 ‘ 08 ” W), in Eldorado do Sul, Brazil, established in 1983. The experiment consisted […]

Oxisol physical attributes affected by surface application of flue dust, aqueous lime, sewage sludges and limestone

Juliano Corulli Corrêa, Leonardo Theodoro Bull, Carlos Alexandre Costa Crusciol, Maria Helena Moraes

01/Apr/2009

The residues flue dust, aqueous lime and sewage sludge (centrifuge and biodigestor) may affect soil physical attributes. The use of industrial and urban residues in soil, with emphasis to sewage sludge, was done in tilled soil, and there are no repports on soil physical attributes affected by these residues on soil surface in no-till system The goal of this study was to evaluate the physical attributes of a an Oxisol in no-till system by surface dispoasal of sewage sludge, flue […]

Soil physical properties in crop-livestock management systems

André da Costa, Jackson Adriano Albuquerque, Álvaro Luiz Mafra, Franciani Rodrigues da Silva

01/Apr/2009

The soil quality of a crop-livestock system can change according to the pasture and soil management. This research was carried out in Otacilio Costa, Santa Catarina State, southern Brazil, on a Humic Cambisol previously used with native grass pasture for 9 years, desiccated in May 2003, for use with ryegrass (Lolium multiflorum) pasture in the winter and corn in the summer. A split plot design was used, consisting of pasture management systems and soil tillage systems prior to the summer […]

Citric acid enhances lead phytoextraction from a soil contaminated by automotive batteries

Eriberto Vagner de Souza Freitas, Clístenes Williams Araújo do Nascimento, Airon José Silva, Gustavo Pereira Duda

01/Apr/2009

Phytoextraction of heavy metals is a promising green technology by which metals are extracted from contaminated soils and transferred to plant shoots. Natural organic acids are an alternative to synthetic chelates since the environmental risks are lower thanks to their biodegradability. The study aimed at evaluating the performance of single and split applications of citric acid on enhancing Pb extraction by maize plants (Zea mays) grown in soil samples from an area contaminated with Pb from battery wastes. The citric […]

Soybean yield variabillity regarding physical properties of a typic acrustox under no-tillage

Gilberto Rosa Filho, Morel de Passos e Carvalho, Marcelo Andreotti, Rafael Montanari, Flávio Ferreira da Silva Binotti, Máila Terra Gioia

01/Apr/2009

Nowadays no-tillage soybean is widely used in crop-livestock farming systems in Brazil. The yield of no-tillage soybean was analysed in the county of Selvíria (latitudes from 20 ° 18 ‘ 05 ” S and 20 ° 18 ‘ 28 ” S and the longitudes de 52 ° 39 ‘ 02 ” W and 52 ° 40 ‘ 28 ” W (Mato Grosso do Sul State – Brazil), in the 2006/07 growing season, as affected by some physical properties of a local Typic Acrustox. The objective was to determine the soil property that could best explain the variability in the agricultural productivity. For this purpose, […]

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