title: Nitrogen dynamics in subtropical fringe and basin mangrove forests inferred from stable isotopes.
abstract: Mangroves exhibit low species richness compared to other tropical forests, but great structural and functional diversity. Aiming to contribute to a better understanding of the functioning of mangrove forests, we investigated nitrogen (N) dynamics in two physiographic types of mangroves (fringe and basin forests) in southeastern Brazil. Because fringe forests are under great influence of tidal flushing we hypothesized that these forests would exhibit higher N cycling rates in sediment and higher N losses to the atmosphere compared to basin forests. We quantified net N mineralization and nitrification rates in sediment and natural abundance of N stable isotopes (δ15N) in the sediment-plant-litter system. The fringe forest exhibited higher net N mineralization rates and δ15N in the sediment-plant-litter system, but net nitrification rates were similar to those of the basin forest. The results of the present study suggest that fringe forests exhibit higher N availability and N cycling in sediment compared to basin forests.
authors.affiliation: Departamento de Ecologia, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, 70910-900, Brazil. carlargreis@hotmail.com.br.
authors.forename: Carla Roberta Gonçalves
authors.initials: CR
authors.lastname: Reis
authors.affiliation: Departamento de Ecologia, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, 70910-900, Brazil.
authors.forename: Gabriela Bielefeld
authors.initials: GB
authors.lastname: Nardoto
authors.affiliation: Departamento de Biologia Vegetal, Universidade Estadual de Campinas, Campinas, SP, 13083-862, Brazil.
authors.forename: André Luis Casarin
authors.initials: AL
authors.lastname: Rochelle
authors.affiliation: Núcleo de Estudos e Pesquisas Ambientais, Universidade Estadual de Campinas, Campinas, SP, 13083-862, Brazil.
authors.forename: Simone Aparecida
authors.initials: SA
authors.lastname: Vieira
authors.affiliation: Departamento de Biologia Vegetal, Universidade Estadual de Campinas, Campinas, SP, 13083-862, Brazil.
authors.forename: Rafael Silva
authors.initials: RS
authors.lastname: Oliveira
mesh_terms: D065928:Forests; D007554:Isotopes; D009584:Nitrogen; D009587:Nitrogen Isotopes; D012987:Soil / Q000737:chemistry; D014197:Trees; D053833:Wetlands
chemical_list: D007554:Isotopes; D009587:Nitrogen Isotopes; D012987:Soil; D009584:Nitrogen
keywords: Nitrification; Nitrogen availability; Nitrogen mineralization; Phosphorus; Stable isotopes