Abstract

This research examines the spatial relationships and predictions obtained by the digital soil mapping approach, model construction and application in central Chile using soil legacy data. The first chapter focuses on the fundamental basis of the digital soil mapping concept and how it is related with the rescue of legacy data. The chapter includes discussion of carbon dynamics and climate factors on soil organic carbon, how carbon and climate might be related, the particularities of the climate factor in central Chile, and some key concepts about climate change. The second chapter analyzes the rescue of legacy data in Chile, the process of harmonization of the data, and the policies involved. It elaborates future soil and environmental data policies and a proposal for national cooperative soil database. The third chapter involves the soil organic carbon modeling using legacy data, the assumptions, and different techniques to define the statistical prediction model for digital soil mapping. Chapter four explores the application of this statistical model on the estimation of soil organic carbon on current and future simulations according to climate change prediction using the NASA-GISS model, showing that carbon will decrease at all depths for every future scenario evaluated.