Share This In Brazil, a study conducted by researchers affiliated with the University of São Paulo (USP) and collaborators showed that deforestation in the Amazon causes an increase in the diversity of antibiotic-resistant bacteria. In Brazil, a study conducted by researchers affiliated with the University of São Paulo (USP) and collaborators showed that deforestation in the Amazon causes an increase in the diversity of antibiotic-resistant bacteria. An article on the study, published in Soil Biology and Biochemistry, compares the microorganisms that live in the soil of native forest with those found in pasture and croplands. The researchers found a far larger number of genes considered markers of antibiotic resistance in deforested than forested areas.