Methodological Advancements in Exploring Spatial and Temporal Variability in Associations between Rural Outmigration and Natural Resource Availability in Resource-Dependent Communities

Stefan Leyk, University of Colorado at Boulder
Galen Maclaurin, University of Colorado at Boulder
Raphael Nawrotzki, University of Colorado at Boulder
Wayne Twine, University of the Witwatersrand
Barend Erasmus, University of the Witwatersrand

Migration-environment models tend to be aspatial, even though the associations between outmigration and environmental explanatory variables are likely to vary across the broader study site. Thus the issue of spatial non-stationarity and temporal variation of migration-environment associations remains unexplored to date. This research expands beyond current approaches by developing migration models at different nested spatial scales (i.e. global, village, and subvillage) to explore the relationships between outmigration and socioeconomic and environmental variables. Demographic survey data from rural South Africa, combined with indicators of natural resource availability from satellite imagery are employed to investigate the spatial and temporal variations in these associations. We show how this nested modeling approach brings out different spatial patterns at finer scales and provides more detail about the observed associations. This allows us to evaluate how a general increase in detail influences model performance and variations in modeled relationships.