Nitrogen Dynamics in Hydrological Flow Paths of a Small Tropical Pasture Catchment

Autor(es)

Salemi, Luiz Felippe ^[1] ; Groppo, Juliano Daniel ^[1] ; Trevisan, Rodrigo ^[1] ; de Barros Ferraz, Silvio Frosini ^[2] ; de Moraes, Jorge Marcos ^{[3, 1]} ; Martinelli, Luiz Antonio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Lab Ecol Isotop, Ctr Energia Nucl Agr, Piracicaba, SP - Brazil

^[2] Univ Sao Paulo, Lab Hidrol Florestal, Escola Super Agr Luiz de Queiroz, Piracicaba, SP - Brazil

^[3] Escola Engn Piracicaba, Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CATENA; v. 127, p. 250-257, APR 2015.
• Citações Web of Science: 5

Resumo

In this paper we report nitrogen (N) dynamics within hydrological flow paths of a small tropical pasture catchment within the Atlantic Rainforest region in Natividade da Serra, Sao Paulo State, Brazil. By collecting soil solution through 27 tension lysimeters, surface runoff through 9 plots, groundwater through one well and one stream over the course of a year, N species concentration and fluxes could be clarified. All hydrological flow paths were dominated by organic N (similar to 60-85%). This finding is explained as a consequence of a drop of soil N cycling rates and N gaseous fluxes previously reported in the literature. Nitrogen input via bulk precipitation (similar to 3.5 kg N ha(-1) year(-1)) exceeded N hydrological output through stream water (similar to 2 kg N ha(-1) year(-1)). Similar findings have been described for pastures of the Brazilian Amazon Basin. If pastures like these are maintained without fertilization, catchments whose land use is old pastures may not be an important direct source of inorganic N for downstream regions. (C) 2015 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 06/55136-0 - Processos hidrológicos e transporte de nitrogênio em bacias com cobertura de floresta e pasto no litoral norte do Estado de São Paulo
• Beneficiário: Jorge Marcos de Moraes
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 06/54292-9 - Estudo do balanço hídrico e balanço biogeoquímico de nitrogênio em uma microbacia de primeira ordem com cobertura de pastagem no litoral norte do Estado de São Paulo
• Beneficiário: Luiz Felippe Salemi
• Modalidade de apoio: Bolsas no Brasil - Mestrado