149 results

Soil aggregate stability after management with crop rotation and chiseling

Juliano Carlos Calonego, Ciro Antonio Rosolem

01/Aug/2008

The objective of this study was to compare, in compacted soil condition, the aggregate stability after different crops rotations under no-tillage system and chiseling. The following crop rotations were repeated for three consecutive years under no-tillage: triticale (X Triticosecale Wittmack) and sunflower (Helianthus annus) as autumn-winter crops, together with pearl millet (Pennisetum glaucum), forage sorghum (Sorghum bicolor) and sunn hemp (Crotalaria juncea) in spring, preceeding soybean (summer crop). In the chiseling treatment the area was kept bare between the autumn-winter […]

Effect of surface liming of a soil under no-tillage on water-soluble cations in the shoot of annual crops

Tiago Roque Benetoli da Silva, Leandro Borges Lemos

01/Jun/2008

Soil acidity in no-tillage systems can be amended by surface liming. This practice is favored by plant residues on the soil surface, which release water-soluble organic compounds that vary among plant species. The experiment was conducted on a Typic Hapludox (V = 41 %) in Botucatu, São Paulo State, Brazil, to evaluate the effect of surface liming on the concentration of soluble cations in millet, common bean and black-oat crop residues in two growing seasons (2002/03 and 2003/04). For common […]

Quantification of tensile strength and friability of an oxisol (Acrudox) under no-tillage

Cássio Antonio Tormena, Marcelo Alessandro Araújo, Jonez Fidalski, Silvia Imhoff, Álvaro Pires da Silva

01/Jun/2008

The soil structural quality is important for plant emergence as well as for crop growth, development and yield. A wide range of soil tensile strength values indicates that soil structure conditions meet these requirements. The objective of this study was to evaluate the tensile strength and friability of an Oxisol (Acrudox) under no-tillage with crop rotation and crop succession. The soil management treatments consisted of: crop succession with wheat and soybean (SDS); crop rotation with corn-oats-soybean-oats-soybean-wheat (SDR) and SDR plus […]

Linear and spatial correlation between common bean yield and porosity of a Red Latosol in Selvíria (MS), Brazil

Marcio Mahmoud Megda, Morel de Passos e Carvalho, Michele Xavier Vieira, Marcelo Andreotti, Elaine Cristina Pereira

01/Apr/2008

Soil porosity influences plant development since root growth and crop yield are determined by the root depth. The objective of this study was to investigate the linear and spatial variability and correlations between common bean yield and soil porosity. The bean grain yield of the irrigated cultivar Carioca IAC was analyzed in the growing season 2004/2005, in Selviria-MS, as well as macroporosity (MA), microporosity (MI) and total porosity (TP), in a Dystroferric Red Latosol, at four depths: 1 (0.0-0.10 m), 2 (0.10-0.20 m), 3 (0.20-0.30 m) […]

Deep-Litter and pig slurry as nitrogen sources for corn

Sandro José Giacomini, Celso Aita

01/Feb/2008

Most of the pig manure generated in the swine production in southern Brazil is handled and stored as liquid manure, but there is a growing interest in adopting the deep-litter production system and using the resulting organic material as fertilizer. A field experiment was carried out on a typic Hapludalf in an experimental area of the Universidade Federal de Santa Maria, Santa Maria, state of Rio Grande do Sul, from October 2002 to March 2003, to evaluate the soil N […]

Soil acidity indicators for liming in no-tillage systems

Margarete Nicolodi, Ibanor Anghinoni, Clesio Gianello

01/Feb/2008

No-tillage systems can change the ratio between soil acidity components and crop yields over the course of time. High crop yields are not seldom observed in highly acid soils. The liming criteria established for conventional tillage soils are likely to be unsuitable for no-tillage soils. The objective of this report was to define liming criteria, based on the yield response to different soil acidity levels and layers in no-tillage systems. Six plantations were sampled in the Planalto region of the […]

Carbon stock and carbon dioxide emissions as affected by soil management systems in Southern Brazil

Falberni de Souza Costa, Cimélio Bayer, Josiléia Acordi Zanatta, João Mielniczuk

01/Feb/2008

Carbon (C) addition through crop residues (residue-C), C dioxide emission (CO2-C) and the soil C stock (soil-C) are components of the C cycle in the soil-plant-atmosphere system. This 18-year study was conducted to identify agricultural practices that could potentially increase C retention in the soil and lessen global warming trends. The three C pools (residue-C, CO2-C and soil-C) under different tillage systems (CT-conventional tillage and NT-no tillage) and cropping systems (O/M-oat (Avena strigosa Schreb)/maize (Zea mays L.) and V/M-vetch (Vicia […]

Soil aggregation and aggregate stability under crop-pasture systems in Mato Grosso do Sul state, Brazil

Júlio Cesar Salton, João Mielniczuk, Cimélio Bayer, Madalena Boeni, Paulo Cesar Conceição, Amoacy Carvalho Fabrício, [...]

01/Feb/2008

Soil management systems, with crops under no-tillage (NT), crops (soybean) in rotation with pastures under NT and permanent pastures (Brachiaria sp.), were evaluated for soil aggregation and aggregate stability. Three long-term experiments (9 and 11 years) in the state of Mato Grosso do Sul were sampled in the layers 0-5, 5-10 and 10-20 cm for determination of the aggregate stability in wet and dry sieving. The mean weight diameter (MWD) and the aggregate stability index (IAS) were calculated. In all experiments, the […]

Changes in some physical properties and in humic fractions of a Nitosol cropped with a millet – soybean succession under no-tillage

Sandro Roberto Brancalião, Maria Helena Moraes

01/Feb/2008

In São Paulo State, the autumn – winter seasons rainfall distribution restriction as well as high temperatures constitute a serious limitation for soil surface covering and crop production. For this reason it is very important to study alternatives for the no tillage system establishment in that State, specially for biomass production and for adequate management for better mulching in amount enough to improve soil physical quality and organic matter content. This study was carried out at the Lageado Experimental Station […]

Hydro-physical properties of an Oxisol under different management systems

Márcio Luis Vieira, Vilson Antonio Klein

01/Dec/2007

Chiseling is one of the mechanical practices that can be used in no-tillage (NT) soils in order to reduce soil bulk density, resistance to root penetration, and to increase water permeability. The effect of these changes on plant growth and consequently on grain yield depends on climatic conditions. In soils with ideal moisture conditions, the physical limitations tend to be less noticeable. This study aimed to analyze the changes in the physical and hydric properties of a chiseled Oxisol under […]

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