By Tei Overgoor (Netherlands)
Rapid land cover changes in the tropics are a major threat to the world’s valuable natural assets such as biodiversity, carbon stock and ecosystems. Demographic dynamics, of which migration is an important component, are often considered to be related to the alterations in land cover. Although the relations between migration and land cover changes have been researched in multiple studies, it is has not yet been conducted using a global scale and a spatial resolution higher than country level simultaneously, due to a lack of spatial explicit data with sufficient extent and resolution. However, in recent years datasets with improved quality have been becoming more available. In this study it was searched for the most suitable global spatial explicit datasets that could be used for testing relations between land cover change and migration. This resulted in the MODIS land cover and the Centre for International Earth Science Information Network (CIESIN) migration dataset. With the use of linear correlations and regression trees relations between the datasets were assessed. This analysis was repeated using a national extent and a higher resolution to compare the results for different spatial scales. It was done for the countries Colombia and Indonesia because spatially distinct patterns with a variety of migration and land cover processes occurred here. The results showed that no significant relation could be found between the land cover change and migration variables both on a global and a national scale. Rather, the forest cover change depended on the size of existing forest stock in the area. Improvements of the study could be higher quality global data with less unknown errors and higher resolution. Furthermore, interactions with other factors, such as biophysical characteristics and local policies, should probably be taken into account.
Keywords: Land cover change; Migration; Geographic information systems; GIS; Tropics.