Nitrate percolation in a Typic Hapludox amended with urban compost waste or inorganic fertilization
01/Sep/2001
The movement of nitrate in soil percolate was evaluated in a field experiment using a Typic Hapludox cultivated with sugarcane and amended with urban compost waste or inorganic fertilizer. The experiment, conducted during the years of 1996/97 and 1997/98, had the following treatments: lime + inorganic fertilization, and control and urban compost waste applied in three levels: 20, 40 and 60 Mg ha-1 (dry weight basis). In the second year (1997/98), the urban compost waste was applied to soil in […]
Strengh mechanical penetrance of an albaqualf soil submitted to different systems of tyllage
01/Sep/2001
Understanding the characteristics and properties of the soils of the state of Rio Grande do Sul low lands, which are being used now with the culture of irrigated rice, is indispensable for the adoption of practices involving irrigation, drainage, correction of acidity and fertility. Mainly when high productivity levels are desired with lower cost and with fewer possibilities of soil and air degradation. The objective of this work was to evaluate compaction of a Planossolo cultivated under different handling systems […]
Growth and nodulation of Acacia mangium, Enterolobium contortisiliquum and Sesbania virgata in heavy metal contaminated soil
01/Sep/2001
One of the great challenges in environmental research today is to find tolerant species of plants and microsymbionts to make viable the revegetation of contaminated areas with heavy metals. This experiment was carried out under greenhouse conditions at the Soil Science Department of the Federal University of Lavras (MG), from August to December 1998, to assess the tolerance to heavy metals and the capacity to establish rhizobia symbiosis with Enterolobium contortisiliquum (tamboril), Acacia mangium (acacia) and Sesbania virgata (sesbânia) in […]
Bean (Phaseolus vulgaris L.) yield and seed quality under the influence of nitrogen split and sources
01/Sep/2001
This research aimed to evaluate the influence of nitrogen sources and application time on yield and quality of bean seed cropped in the winter period. A clayey typic Haplustox was used in a 2 x 7 factorial scheme, with 2 N sources (urea and ammonium sulfate) and 7 application time combinations (0-0, 0-75, 15-60, 30-45, 45-30, 60-15, and 75-0 kg ha-1 of N, respectively at sowing time and 22 days after plant emergence). Treatments were supplied 60 kg ha-1 P2O5 […]
Characterization of iron-manganese concretions of limestone-derived soils from Northern Minas Gerais
01/Sep/2001
The occurrence of iron-manganese concretions, which vary in diameter and shape, are common in limestone-derived soils from northern Minas Gerais, Brazil. Normally, they tend to increase their size with depth in Cambisols (Inceptisols) and Vertisols, and to remain small in Latosols (Oxisols), where they are smoother and more rounded. Aiming to study them, concretions in the B horizons of Red Latosols, B and BC horizons of Cambisols and C horizons of Vertisols were collected and grouped according to their average […]
Soil dissipation of simazine by action of earthworms (Eisenia foetida)
01/Sep/2001
The soil contains a large variety of macroscopic and microscopic organisms, which compete for the available resources. Fertilizers and pesticides usually applied in soil to increase the agricultural production may determine environmental changes. Among the edaphic organisms, earthworms are outstanding for their number and role they play on soil characteristics. The performance of earthworms on the persistence, transformation and bioaccumulation of simazine was assessed in a soil treated with the herbicide. The earthworms were sensitive to simazine [CL50(14 days) of […]
Soil and water losses under corn following oats and bare-fallow using conventional and no-till planting performed with animal and tractor traction
01/Sep/2001
Using simulated rainfall on a 0.12 m m-1-slope typic Hapludalf (Red Yellow Podzolic Soil), sandy-loam soil, erosion losses by water were evaluated during corn (Zea mays L.) that had followed oats (Avena strigosa Schieb) and bare-fallow in the winter. Field work was conducted at the Silviculture Experimental Station of the Secretary of Agriculture of Rio Grande do Sul, Brazil, from 1994 to 1995. Conventional and no-tillage performed with animal and tractor traction were the main treatments studied. Rainfall was applied […]
Utilization of a geographic information system on land use evaluation in Botucatu (SP)
01/Sep/2001
The GIS-IDRISI was used to check land use adequacy from 1997 to 1998, in the initial part of the Rio Pardo basin, in Botucatu/Pardinho (SP), to obtain a suitable land use planning of the area. The classes and subclasses of land capability were determined according to the Land Capability Classification System. The lands of the studied area were classified as: class VIe, lands with erosion susceptibility (90.49%); class Va, flat lands, with no erosion risk, but limited by excess of […]
Nutrient leaching potential following application of papermill lime-sludge to an acidic clay soil
01/Sep/2001
This experiment was carried out under greenhouse conditions with soil pots during 210 days, to evaluate the effect of calcitic papermill lime-sludge application (at the rates 0, 773, 1.547, and 2.320 mg kg-1 or respective equivalents to control, 2, 4, and 6 t ha-1), on chemical composition of soil leachate and its effects on eucalypt growth and yield. Highest soil leachate pH, SO4, and Na concentrations occurred in the 4 and 6 t ha-1 treatments. Soil leachate nitrate concentrations decreased […]
Biological nitrogen fixation efficiency by strains of Bradyrhizobium in soybean under no-tillage
01/Sep/2001
This study was carried out in the 1994/95, 1996/97, 1997/98 and 1998/99 cropping seasons, to evaluate the efficiency of the Bradyrhizobium strains as recommended by research, evaluation and biological nitrogen fixation efficiency of competitiveness of soybean crop under no-tillage. The experiments were carried out at FUNDACEP, in Cruz Alta, Rio Grande do Sul, Brazil, in an area cultivated under no-tillage over five to ten years. In the year of 1994/95, the treatments were: non-inoculated control; 200 kg ha-1 of nitrogen […]