Growth and yield in mangrove forests of the Federated States of Micronesia

Abstract

Permanent mangrove forest plots in the Federated States of Micronesia (FSM) were installed in 1983 and remeasured during 1990–92. Species from slowest to fastest growing as determined by mean annual diameter increments over all size classes were Rhizophora apiculata (0.25 cm yr −1), Xylocarpus granatum (0.31 cm yr −1), Bruguiera gymnorrhiza (0.35 cm yr −1), Rhizophora mucronata (0.37 cm yr −1), and Sonneratia alba (0.49 cm yr −1). The FSM-level mean annual volume increment was 4.5 m 3 ha −1 yr −1, with an additional 0.7 m 3 ha −1 yr −1 harvested during the measurement interval. Results of this study are comparable to values obtained in Southeast Asia. Species-specific rotation lengths varied as much as six-fold between samples including all trees and those including only the fastest-growing trees within each size class. High variability in growth rates among trees and plots suggests considerable scope for gains in productivity through silvicultural interventions.