Decomposi o e dinamica de libera o de nitrog那nio e f車sforo de fra es vegetais de Salvinia auriculata Aubl. em um reservat車rio da Amaz nia legal = Decomposition and release dynamics of nitrogen and phosphorous from vegetal fractions of Salvinia auriculata Aubl. in a Legal Amazon reservoir

作者：Deivid Sousa Silva; Marcela Bianchessi da Cunha Santino; Elineide Eugenio Marques

来源：Acta Scientiarum - Biological Sciences, 2011.

• macrofitas aquaticas
• sacos de decomposi o
• UHE Lajeado
• Estado do Tocantins
• aquatic macrophyte
• litterbags
• UHE Lajeado
• Tocantins State

Este estudo teve como objetivo determinar os coeficientes de decomposi o da parte submersa (PS) e a谷rea (PA) de Salvinia auriculata em duas profundidades da coluna de 芍gua (superf赤cie e sedimento). Tamb谷m visou avaliar o rendimento do processo de perda de massa assim como a evolu o temporal dos teores de f車sforo e nitrog那nio. As macr車fitas foram separadas em partes; em seguida, foram secas at谷 peso constante. Os materiais vegetais foram depositados em sacos de decomposi o e incubados no reservat車rio da UHE Lajeado, Tocantins. As an芍lises dos resultados de perda de massa revelaram que n o houve diferen as significativas entre os PA-sed e PA-sup (p %26gt; 0,05), entretanto, os PA-sed foram significativamente diferentes dos PS-sed (p 0.05). However, the AP-sed was significantly different from SP-sed (p %26lt; 0.05) and SP-sur (p %26lt; 0.01). The AP-sed presented a decay coefficient (k) of 0.0102 day-1 and AP-sur a k of 0.0067 day-1. The SP-sed presented a k of 0.0027 day-1 and the SP-sur 0.0040 day-1. It was also noticed that during the first days ofdecomposition great amounts of nitrogen and phosphorous were solubilized. This event was related to the leachate process; from the 14th day of decomposition, an increasing trend was observed in nitrogen concentrations. This fact was probably related to detritus enrichment by microbial colonization.