Anthropogenic pressure on global sediment fluxes and reserves: Towards monitoring and documenting challenges and opportunities

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Sand and gravel make up the most extracted group of materials worldwide, even exceeding fossil fuels and are a key ingredient for modern civilization. However, today, sand and gravel are being extracted faster than they can be replenished and we have no knowledge of how much material there is and where it is mined from. Furthermore, the extent of illegal or undocumented activity is increasing and with more people on the planet, the need for sediment will continue to add pressure on the known resources and increase the likelihood of illegality. With the current pace of extraction, demand might outstrip the supply by midcentury. The importance of these materials require monitoring of sand resources and a comprehensive understanding of sand fluxes and extraction - both legal and illegal - to promote and ensure responsible extraction and future sustainable use of this material. The research program will examine the Anthropogenic pressure on sediment through two main Research Objectives. Objective I takes a remote-sensing approach to identify mining sites and examine potential conflicts and synergies with the natural environment with potentially far-reaching effects on ecology, local infrastructure, and human livelihoods focusing on Africa. The overall goal is to assess and understand extraction activities and establishing a spatial overview of sand extraction and its interlinkages with humans and nature. Objective II focuses on understanding high Arctic processes controlling sediment fluxes from melting glaciers to the coasts. The overall goal is to better understand sediment delivery to the Arctic oceans in a warming climate and to investigate whether these systems provide a new mode of opportunities for sediment extraction to relieve the growing global demand for sediment, thereby linking the two objectives of the proposed research program. The objectives for my research program focus on geographical areas where Anthropogenic pressure is particularly large; in Africa where the population is expected to grow from 1b today to 2.4b in 2050, and in the Arctic, where climate change is particularly pronounced. The specific objectives are: I) Examine the landscape implications of growing global demand for sediment focusing on the increasingly populated African continent and II) Constrain sediment dynamics and fluxes from ice covered regions to the coast in the Canadian Arctic. The research focussing on Africa can lead to a breakthrough in geohealth science and urban-studies when linking housing and infrastructure development, essential for projecting future urban growth. Additionally, it can improve the basis for environmental conservation actions, which have failed to include threats of sand mining activities. In an Arctic perspective, the research is highly relevant for Indigenous communities, local societies and stakeholders in the planning of future infrastructure and overall livelihood stability in these rapidly changing environments.