Summary
Increasingly alarming trajectories of accelerating earth system change, supply chain risks, and growing environmental pressures emphasize that the current efforts to address these issues are insufficient. There is an urgent need to understand the scale, intensity, and spatiotemporal structure of the physical material and energy flows that drive these changes. However, there is also a persistent gap between research disciplines, models, and data needed to monitor the human-nature interactions that characterize our physical economy. Against this backdrop, the aim of my research was to investigate how we can use material flow analysis (MFA) to model and integrate the human and natural physical subsystems in a mass-balance-consistent manner, and to explore how MFA principles can be applied to map, quantify, and account for geological stock changes, as well as track the flows of mineral raw materials across the coupled human-natural system.
This thesis addresses key challenges that hinder consistent monitoring of natural resource extraction and waste production along the complex supply chains of material systems by (1) compiling a comprehensive, integrative review of the current status of mineral resource mapping and national accounting in order to develop a new framework for modeling geological stocks in a manner that facilitates more robust and systematic national accounting; (2) demonstrating how an integrated MFA systems approach could provide a useful framework for guiding sustainable development policies using sand supply networks as an example; and (3) identifying and illustrating common misconceptions and hidden uncertainties that create problems and misunderstandings for users of mineral statistics and of data on material stock and flows. The work in this thesis shows how an integrated systems perspective and more robust monitoring of the physical economy can help to assess and address sustainability trade-offs, thereby facilitating more effective strategies for managing the complexity of growing resource consumption within planetary boundaries.
