Structure and dynamics of coconut-based agroforesty systems in Melanesia : a case study from the Vauatu archipelago
Résumé
Coconut (Cocos nucifera)-based agroforestry systems hold promise as a sustainable
land use activity in the Melanesian islands, where food dependency on foreign sources and
land shortages are increasing drarnatically. This chapter describes the dynamics of these
smallholder production systems in the Malo Island of northern Vanuatu (Melanesia), where a
dual economy operates in which resources are dedicated to both subsistence and commercial
production. The floristic elements found in the coconut plantations were typical of those
described in the hurnid tropical homegardens elsewhere, with an average of 12 tree species
per plot. Mean Shannon Weaver index was 1.57 with the vertical profile of vegetation having
one-to-five strata. Although the coconut palrns dorninate these production systems, in certain
cases other trees may dominate it. Situations in coconut plots evolve throughout the
development phase of the palms. Based on that, five types of smallholder coconut-based
agroforestry systems were recognized, which falls into two main evolutionary patterns: (1) a
perennial occupation of the cultivated land by coconut trees, because of coconut replanting,
and (2) a gradua1 return to tree fallow in which the coconut palms gradually disappear
because of changes in the complex multistrata vegetation.