Master’s Thesis Abstract

PHYSICOCHEMICAL FACTORS CONTROLLING WOOD DECOMPOSITION IN

THREE FLORIDA MANGROVES

by

Luz Maria Romero

Florida International University, 1999

Miami, Florida

Professor James W. Fourqurean, Major Professor

The purpose of this study was to conduct a 13-month study to follow changes in mass and nutrient constituents during decomposition of wood disks from three mangrove species. I used a four factor experimental design, with species, condition (soil surface, air and buried), site and time as factors. Wood disks decomposed in two phases. Approximately 15% of wood biomass decomposed rapidly while the remaining 85% decomposed much more slowly. There was a condition effect on the decay rates for the slow decay component (k₂). Mean k₂ was highest for disks in the soil surface treatment (0.019 ± 0.001 month^-1) and lowest for the air treatment (0.004 ± 0.001). There was net immobilization of nitrogen in Laguncularia racemosa disks decomposing on the soil surface and net mineralization of nitrogen in Avicennia germinans and Laguncularia racemosa wood disks. There was net mineralization of phosphorus for all treatment levels.