Volume 34, Number 4, 2010
Nutrient extraction and export by fully irrigated sugarcane varieties
01/Aug/2010
A review of technology research supporting the Brazilian sugaralcohol sector shows that only sporadic studies with irrigated sugarcane have been developed to investigate nutritional requirements. In this context, the objective of this study was to quantify the capacity of extraction and export of N, P, K, Ca, and Mg as well as the nutritional requirement for the production of one ton of stalk per hectare (TCH) in the plant cane cycle of 11 sugarcane varieties (SP79-1011, RB813804, RB863129, RB872552, RB943365, […]
Restoration of the soil structure by crop sequences established in no-till, as related to water erosion in distinct surface physical conditions
01/Aug/2010
Soil structure plays a prominent role in plant growth and erosion control, and consequently in food production and soil and water conservation. This research was developed with the objective of implementing and accompanying the restoration process of the structure of a degraded soil, by planting crop sequences under no-tillage (autumn-winter and spring-summer, grass and legume, in single and intercropped systems), and later verifying the relations with water and soil losses caused by rainfall erosion, under distinct surface physical conditions (untilled […]
Soil aggregation in a crop-livestock integration system under no-tillage
01/Aug/2010
Grazing intensities can influence soil aggregation, which can be temporarily and permanently affected. The objective of this study was to evaluate the aggregate stability in water at the end of a soybean cycle and during pasture development in a crop-livestock integration system under no-tillage and grazing intensities. The experiment was initiated in 2001, in a dystrophic Red Latosol, after soybean harvest. Treatments consisted of pasture (black oat + Italian ryegrass) at heights of 10, 20 and 40 cm, grazed by young […]
Long-term swine manure fertilization and its effects on soil chemical properties in santa catarina, southern Brazil
01/Aug/2010
Swine manure is a good nutrient source, but may have a negative impact on the environment when inadequately used. The aim of this work was to evaluate changes in properties of soils under no-till grain production and long-term swine manure fertilization. Soil samples from three representative soils types (Oxisol, Inceptisol and Leptosol) from Western Santa Catarina, Southern Brazil, were collected under no-tillage cultivation and surface application of swine manure for about 15 years and over 20 years. Samples from areas treated with […]
Chemical phophorus extractors used as environmental indicators in sewage-sludge treated soil
01/Aug/2010
Sewage sludge (SS) application to agricultural soils can raise the levels of some nutrients inadequately, for example P. In practice, the applied SS doses are based on the N requirement of crops, in which the P requirement or final destination of the applied P in the residue is not taken into account. Phosphorus is often associated with the eutrophication of water bodies, for being transported by runoff. The objective of this study was to evaluate if three chemical extractors used […]
Soil quality indicators in lead mining and metalurgy area. I – microrganisms
01/Aug/2010
Microorganisms are the most numerous organisms in the soil biological fraction. Their population and metabolic relations are affected by environmental changes, such as pollutant deposition on and movement into the soil. The aim of this work was to assess the soil microbial activity in a Pb mining and metallurgy plant, in Adrianópolis (PR), to determine soil biological quality indicators. The soil (layers 0 to 5 and 5 to 10 cm) was sampled once at five locations four times (May, September, November […]
Soil quality indicators in lead mining and metalurgy area. II – Mesofauna and plants
01/Aug/2010
The influence of soil management or the contaminant application to the soil, usually induce to a quicker response in the soil mesofauna than in other pedogenic properties; these organisms are therefore good environmental quality indicators. The aim of this study was to identify and quantify the organisms groups of the soil mesofauna and determine Pb and Zn contents in plants in the mining and metallurgy plant in Adrianópolis (PR),to originate biological indicators of the quality of these solis. At the […]
Irrigation with domestic wastewater: a multivariate analysis of main soil changes
01/Aug/2010
Irrigation with treated domestic sewage wastewater (TSE) is an agricultural practice to reduce water requirements of agroecossystems and the nutrient load impact on freshwaters, but adverse effects on soil chemical (salinization, sodification, etc.) and soil physical properties (alteration in soil porosity and hydraulic conductivity, etc.) have been reported. This study aimed to define some relationships among these changes in an Oxisol using multivariate analysis. Corn (Zea mays L.) and sunflower (Helianthus annuus L.) were grown for two years, irrigated with […]
Quality of a revegeted mine spoil in the federal disrict of Brazil
01/Aug/2010
The use of organic residues has been shown to be effective for the revegetation of mined areas. However, data on the quality of mine spoils treated with organic residues are rather scarce. This study aimed to evaluate the spoil quality of a mined area in the Brazilian Federal District treated with 250 Mg ha-1 of domestic sewage sludge and covered with herbs grown from seeds. The soil attributes used for the evaluation were bulk density, total porosity, available water capacity, soil resistance […]
Copper, zinc and manganese in soils of two watersheds in Santa Catarina with intensive use of pig slurry
01/Aug/2010
Systematic pig slurry application to crop soils may lead to the accumulation of heavy metals in regions with intensive pig raising. The aim of this study was to evaluate the accumulation of Cu, Zn and Mn in soils under systematic pig slurry application. For this purpose, soil samples were collected from two of the most representative watersheds of Santa Catarina where the predominant activity is pig raising. In each watershed, 12 properties were chosen to evaluate the different systems of […]
