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 […]
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 […]
Copper and zinc forms and accumulation in soil after successive pig slurry applications
01/Jun/2010
Successive applications of pig slurry in the soil can increase the levels and change the forms of copper (Cu) and zinc (Zn). The objective of this study was to evaluate Cu and Zn accumulation and forms in the soil of areas with successive pig slurry applications under no tillage crop rotation. The experiment was carried out in a Typic Hapludalf in the experimental area of the Department of Agricultural Engineering of the Federal University of Santa Maria, Santa Maria (RS), […]
Soil phosphorus alteration by pig slurry application
01/Dec/2008
Pig slurry serves as plant nutrient source, but may cause phosphorus accumulation in the soil when used improperly, which later can be transferred to the aquatic environment causing eutrophication. The objective of this study was to evaluate the potential risk of environmental contamination by continuous use of pig slurry, measuring alterations in phosphorus content in the soil and in the sorption isotherms. The study was carried out at the Universidade Federal de Santa Maria, in a Typic Hapludalf. The effects […]
Paclobutrazol transport in soil columns
01/Oct/2008
Paclobutrazol (PBZ) is a post-emergence plant growth regulator used in agricultural systems with the objective of vegetative control growth, thereby increasing the reproductive capacity of the plant. This growth regulator remains active in the soil for several years being detrimental to subsequent tillage and contamination of groundwater through leaching. The objective of this work was to study the mechanisms involved in the transport and sorption of PBZ in an Ultisol and a Vertisol, both of the São Francisco Valley, Brazil. […]
Soil organic matter determination by weight loss-on-ignition in samples from the state of Rio Grande do Sul, Brazil
01/Apr/2007
The search for methods to determine the content of soil organic matter (SOM) that do not generate hazardous waste is important. SOM oxidation with dichromate is used in most Brazilian soil laboratories and it generates chromium-contaminated waste. The objective of this study was to evaluate the weight loss-on-ignition (LOI) method in comparison to the wet digestion procedure based on sulfuric acid-chromium solution as commonly used in soil analysis laboratories of Rio Grande do Sul (RS) and Santa Catarina (SC) states, […]
