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

沙子和砾石构成了世界上提取最多的一组材料，甚至超过了化石燃料，是现代文明的关键成分。然而，今天，沙子和砾石被开采的速度快于它们被补充的速度，我们不知道有多少材料以及从哪里开采出来的。此外，非法或无证活动的程度正在增加，随着地球上人口的增加，对沉积物的需求将继续增加对已知资源的压力，并增加非法的可能性。按照目前的开采速度，到本世纪中叶，可能会供不应求。这些材料的重要性要求监测沙子资源，全面了解沙子的流动和提取--包括合法和非法的--以促进和确保负责任地提取和今后可持续使用这种材料。该研究计划将通过两个主要的研究目标来研究人类对沉积物的压力。目标一采用遥感方法确定采矿地点，审查与自然环境的潜在冲突和协同作用，可能对生态、当地基础设施和人类生计产生深远影响，重点放在非洲。总的目标是评估和了解采砂活动，并对采砂及其与人类和自然的相互联系建立一个空间概览。目标二侧重于了解控制从冰川融化到海岸的沉积物通量的北极高地过程。总体目标是更好地了解在气候变暖的情况下沉积物向北冰洋的输送，并调查这些系统是否提供了一种新的沉积物提取机会模式，以缓解全球对沉积物日益增长的需求，从而将拟议研究计划的两个目标联系起来。我的研究计划的目标集中在人为压力特别大的地理区域；在非洲，人口预计将从今天的10亿增长到2050年的24亿；在气候变化特别明显的北极。具体目标是：i)审查全球对沉积物日益增长的需求对景观的影响，重点放在人口日益增加的非洲大陆；ii)限制沉积物的动态和从冰盖区域流向加拿大北极沿海的通量。将住房和基础设施发展联系起来，对于预测未来的城市增长至关重要，聚焦于非洲的研究可以在地球健康科学和城市研究方面取得突破。此外，它还可以改善环境保护行动的基础，这些行动没有包括采砂活动的威胁。从北极的角度来看，这项研究与土著社区、当地社会和利益攸关方在这些快速变化的环境中规划未来基础设施和总体生计稳定方面具有高度相关性。

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.