149 results

Rill erosion under different soil tillage methods and soil consolidation

M. J. Schäfer, J. M. Reichert, E. A. Cassol, F. L. F. Eltz, D. J. Reinert

01/Jun/2001

Soil tillage and consolidation modify soil resistance to rill erosion. Thus, an experiment was carried out on a Hapludulf, under field conditions in 1997/98, to study rill erosion under different tillage methods and soil consolidation, to evaluate the sediment size and to determine rill erodibility (Kr) and critical shear stress (τc). The experiment was completely randomized with six replications, using the following treatments: recent conventional tillage (RCT), two-month consolidated conventional tillage (CCT), no-tillage with mulch (NTM) with 94% surface coverage […]

Interrill erosion for different tillage and soil consolidation

M. J. Schäfer, J. M. Reichert, D. J. Reinert, E. A. Cassol

01/Jun/2001

A tilled soil has increased susceptibility to raindrop impact and sediment transport by laminar surface flow and splash, but after tillage the soil reconsolidates, increasing again its resistance. Thus, an experiment was conducted on a Hapludalf with Sandy loam soil surface, under no-tillage for eight years, to evaluate interrill erosion under different tillage methods. The experiment was totally randomized with six replicates. The treatments were recent conventional tillage (RCT), two-month consolidated conventional tillage (CCT), no-tillage with mulch (NTM) with 94% […]

Cover crops as a source of nitrogen to corn

C. Aita, C. J. Basso, C. A. Ceretta, C. N. Gonçalves, C. O. Da Ros

01/Mar/2001

A field experiment was carried out from 1990 to 1994 in the experimental area of the Soil Department at the Federal University of Santa Maria, State of Rio Grande do Sul, Brazil, on an Hapludalf to evaluate the potential of some winter legumes as N suppliers to no-tillage corn. A completely randomized block design with split-plots was used, with the winter crops in the main plots and the N rates for corn in the split-plots. In the main plots, the […]

Resistance to penetration and permeability of a typic dystrophic red latosol under management systems in the cerrado region

A. N. Beutler, M. L. N. Silva, N. Curi, M. M. Ferreira, J. C. Cruz, I. A. Pereira Filho

01/Mar/2001

The direct consequences of inadequate soil management are erosion, productivity reduction and loss of sustainability. This study aimed to evaluate the resistance to penetration and permeability of soil to water under management systems used in the cerrado region. The study was conducted at Embrapa Corn and Sorghum, in Sete Lagoas (MG), using a cerrado phase, very clayey, typic dystrophic Red Latosol (Acrusthox). The native cerrado provided lower soil density, higher macroporosity, higher total volume of pores, and consequently, smaller resistance […]

Aggregation of typic dystrophic Red Latosol (Oxisol) related to management at cerrado region in Minas Gerais, Brazil

A. N. Beutler, M. L. N. Silva, N. Curi, M. M. Ferreira, I. A. Pereira Filho, J. C. Cruz

01/Mar/2001

The direct consequences of inadequate soil management are erosion, reduction of productivity and loss of sustainability. The indicators of soil structure quality are important tools for evaluating sustainability of management systems. This study aimed to evaluate the aggregation of typic dystrophic Red Latosol (Oxisol) under different management systems at cerrado region in Sete Lagoas, Minas Gerais, Brazil. Among the studied management systems, no-tillage presented higher percentage of aggregates in the > 2 mm class, smaller percentage in the < 2 mm and < 1 mm classes, […]

Intercropped black oat and common vetch as soil cover and their effect on corn

C. G. Bortolini, P. R. F. Silva, G. Argenta

01/Dec/2000

With the increase of corn cultivation under the no-tillage system, various cover crop species have been evaluated to obtain a soil cover that benefits corn under succession and no-tillage. The objective of this work was to evaluate the effect of three sowing densities of black oat (Avena strigosa Scheig) and common vetch (Vicia sativa) in associated crops and as isolated crops and three levels of nitrogen fertilization (N), applied on corn (0, 60 and 160 kg ha-1 of N). Dry […]

Soil erosion of a clayey inceptisol under different crop and tillage systems: II. nutrient and organic carbon losses

J. Schick, I. Bertol, A. A. Balbinot Júnior, O. Batistela

01/Jun/2000

Erosion is one of the main causes of soil degradation because of the transport of nutrients. The nutrients are transported by water either dissolved or adsorbed on the soil particles, and the erosion rate may vary according to the tillage system. This work was conducted at the Centro de Ciências Agroveterinárias in Lages, Santa Catarina, Brazil, from January 1993 to October 1998, to quantify the losses of phosphorus, potassium, calcium, magnesium and organic carbon due to erosion caused by natural […]

Nitrogen balance of solid and liquid nitrogen sources on side-dressed no-till corn system at Triângulo Mineiro (MG)

W. A. R. Lara Cabezas, P. C. O. Trivelin, G. H. Kondörfer, S. Pereira

01/Jun/2000

Urea and uan were side-dressed applied on the soil surface and incorporated (5-7 cm) to corn in a no-tillage system to study the balance of urea-N (15N) at harvest and measure the accumulated losses of NH3-N derived from these sources and from urea + KCl (solid) and uan + KCl (liquid), applied as 06-00-09 (N-P2O5-K2O) to the surface only. The treatments-originated from a factorial 1 + (2 x 2) + 2, with plot being + factorial 2 x 2 (two […]

Water erosion in clayey inceptisol in different crop and tillage systems: I. soil and water losses

J. Schick, I. Bertol, O. Batistela, A. A. Balbinot Júnior

01/Jun/2000

Raindrop impact and runoff are the active agents of water erosion, which is influenced by soil roughness and cover, crop type and tillage system. Conservation tillage reduces water erosion in relation to conventional tillage by means of surface roughness and cover. This work was conducted in Centro de Ciência Agroveterinárias, in Lages, Santa Catarina, Brazil, from January 1993, to October 1998 to quantify soil and runoff losses under natural rainfall in the following soil tillage downslope systems: no-tillage, chisel plow […]

Soil bulk density, chemical attributes and corn root distribution as affected by grazing and soil management

V. R. Silva, D. J. Reinert, J. M. Reichert

01/Mar/2000

Farming and cattle-raising integrated system is an alternative to increase farmers’ yield in southern Brazil (29o 45´south and 53o 42´ west Greenwich). However, grazing and, or, soil tillage may cause soil compaction at levels that can affect root growth and crop yield. The effect of animal trampling in continuous grazing during winter/spring (cold season) and soil management system effects on soil compaction, chemical attributes and root distribution were studied. The soil used was a Red-Yellow Podzolic (Hapludalf), with a loam […]

1 12 13 14 15