Spatial Representation of Land Use and Population Density: Integrated Layers of Data Contribute to Environmental Planning in Vanuatu

  Abstract We propose the integration of six data layers (topography, isohyets, soil potential, household localization, vegetation types and land lease titles) to assess the constraints facing food production in Vanuatu, Melanesia. All layers are digitalized allowing area computations of polygons associated with the various data sets. For each island, the following are computed: total area, good arable land area, coconut plantations, pastures/grasslands, area under land lease titles and average accessible good land per household. Although Vanuatu is often considered as not densely populated (19 hab/km2), results indicate great variation among islands. The average area of good land per household varies from 530 ha on the island of Tegua (North) to 0.5 ha on Futuna (South). Shifting cultivation does not appear to be a serious threat to the environment. The establishment of coconut plantations and permanent pastures represents the main cause of deforestation and contributes to increased pressure on land used for food production. The integration of layers of data is a powerful tool for improving environmental planning in an archipelago under growing human pressure and natural changes.