1. Dep. of Soil, Lab. of Soil Biological Chemistry; Federal Rural Univ. of Rio de Janeiro (Univ. Federal Rural do Rio de Janeiro-UFRRJ); Rodovia BR 465 km 7 Seropédica RJ 23890-000 Brazil
2. Dep. of Environmental Biology, Agricultural Chemistry and Biology Group-CMI Roullier, Faculty of Sciences; Univ. of Navarra; Navarra Spain