1. Center for Nuclear Energy in Agriculture; University of São Paulo; CENA/USP; Piracicaba; SP; Brazil
2. Department of Soil Science; University of São Paulo; ESALQ/USP; Piracicaba; SP; Brazil
3. Laboratory of Environmental Microbiology; EMBRAPA Environment; Jaguariúna; SP; Brazil
4. Department of Natural Resources and Environmental Sciences; University of Illinois; Urbana; IL; USA