1. Soil and Engineering Department; Federal University of Parana; Curitiba Brazil
2. Soil Laboratory; Universidade Estadual do Norte Fluminense Darcy Ribeiro; Campos dos Goytacazes Brazil
3. Géoscience Environnement Toulouse; Toulouse France
4. Laboratório de Ecologia Isotópica, Centro de Energia Nuclear na Agricultura; University of São Paulo; Piracicaba Brazil
5. Departamento de Ciências Ambientais; Federal University of São Paulo; Diadema Brazil
6. Department of Soil Science; University of São Paulo; Piracicaba Brazil