A Discussion on the results of the 1971 Royal Society - Percy Sladen Expedition to the New Hebrides - Soils of the New Hebrides islands

This paper deals with the pedogenesis, the classification, the characteristics and the geography of New Hebrides soils, and lastly with some relationships between these soils and the vegetation. The following pedogenetic features are emphasized: the New Hebrides soils derive mainly from basic volcanic rocks. They are often young or frequently rejuvenated by volcanic ash. They are differentiated in three main groups, according to a climatic sequence due to the tradewinds: ferrallitic soils in the wetter southeast part, fersiallitic soils in the drier northwest part, and andic soils on the 'perhumid’ highlands. The wetter the climate or the younger the volcanic ash, the more andic are the soils. A correlation is attempted between the soil units of the French pedological classification and those of the soil map of the world by the F. A. O. Next, the characteristics and the geographical distribution of the thirteen main groups of New Hebrides soils are briefly outlined. Finally, some relationships between some soils and the native vegetation are briefly reported.