Physical, chemical, and biological properties of soil under soybean cultivation and at an adjacent rainforest in Amazonia

• Autor(a) principal: Beldini,Troy Patrick
• Data de Publicação: 2015
• Outros Autores: Oliveira Junior,Raimundo Cosme de, Keller,Michael Meier, Camargo,Plinio Batista de, Crill,Patrick Michael, Silva,Alessandra Damasceno da, Santos,Darlisson Bentes dos, Oliveira,Daniel Rocha de
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista Ambiente & Água
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1980-993X2015000400707
• topic: land use change; microbial metabolic quotient; seasonality

Land-use change in the Amazon basin has occurred at an accelerated pace during the last decade, and it is important that the effects induced by these changes on soil properties are better understood. This study investigated the chemical, physical, and biological properties of soil in a field under cultivation of soy and rice, and at an adjacent primary rain forest. Increases in soil bulk density, exchangeable cations and pH were observed in the soy field soil. In the primary forest, soil microbial biomass and basal respiration rates were higher, and the microbial community was metabolically more efficient. The sum of basal respiration across the A, AB and BA horizons on a mass per area basis ranged from 7.31 to 10.05 Mg CO2-C ha-1yr-1, thus yielding estimates for total soil respiration between 9.6 and 15.5 Mg CO2-C ha-1yr-1across sites and seasons. These estimates are in good agreement with literature values for Amazonian ecosystems. The estimates of heterotrophic respiration made in this study help to further constrain the estimates of autotrophic soil respiration and will be useful for monitoring the effects of future land-use in Amazonian ecosystems.