C And N Stocks And Soil Organic Matter Dynamics In Succession Agroforestry Systems In Brazil.

Soil organic matter is closely linked to the quality of Agroecosystems and directly influences the agricultural production and the environmental conditions. Understanding of soil organic matter dynamics in agroforestry systems requires studies with a temporal focus, since the changes in its chemical composition tend to follow a gradual behavior. The aim of this study was to investigate the dynamics of changes in stocks and chemical composition of soil organic matter under agroforestry, using systems in different stages of vegetation succession.

Copper and Zn distribution in humic substances of soil after 10 years of pig manure application in south of Santa Catarina, Brazil.

This study aims to evaluate available Cu and Zn levels in soil and related in soil organic matter (SOM) fractions (fulvic acids-FA, humic acids-HA, and humins-HU) after 10 years of application of pig slurry (PS) and pig deep litter (PL). Soil samples were collected from an experiment with black oat/corn succession under no-tillage in southern Brazil. The treatments consisted of fertilization of 90 and 180 kg N ha applied as PS and PL from 2002 to 2012 and a control treatment without any fertilization.

Accelerated degradation of (14)C-atrazine in brazilian soils from different regions.

The repeated use of a given pesticide may induce a selection of the soil microbial population, resulting in a rapid degradation of the respective xenobiotic. Patterns of atrazine degradation (mineralization, formation of metabolites and nonextractable residues (NER)) were evaluated in two Brazilian soils with a history of atrazine application. Results were compared with those obtained from soils that had no agricultural use or herbicide application history.