DEFORESTATION AND CULTIVATION WITH MAIZE (Zea mays L.) HAS A PROFOUND EFFECT ON THE BACTERIAL COMMUNITY STRUCTURE IN SOIL

摘要

In this study, the effect of deforestation and cultivation of maize (Zea mays L.) on the physicochemical characteristics and the bacterial community structure in soil were studied at the national park Area de Proteccion de Flora y Fauna Nevado de Toluca in Mexico. Soil was sampled from three forested areas in the national park, from three deforested areas grazed by animals and from three areas cultivated with maize. The soil was characterized chemically and biologically, whilst the bacterial community structure was investigated through 454 pyrosequencing of the 16S rRNA gene. The pH in the forest soil decreased from 6.1 to 5.3 in the maize-cultivated soil, whilst the soil organic C content decreased 1.4 times in the arable soil compared with the forest soil. The microbial biomass C decreased 2.9 times in the arable soil compared with the forest soil, but the metabolic quotient qCO(2) (ratio basal respiration to microbial biomass C) nearly doubled. Deforestation and maize cultivation reduced the abundance of Proteobacteria, Actinobacteria and Bacteroidetes, whereas Acidobacteria, Chloroflexi, Gemmatimonadetes and Firmicutes were resistant to these changes. It was found that soil characteristics were affected negatively by deforestation and nearly half of the organic matter was lost, and on these sloped fields, erosion will be high, further decreasing soil fertility. Although the relative abundance of a number of bacterial groups was reduced by deforestation, others were not affected by land-use change. Copyright (C) 2014 John Wiley & Sons, Ltd.