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

沙子和砾石是世界上开采量最大的材料，甚至超过了化石燃料，是现代文明的关键成分。然而，今天，沙子和砾石的开采速度比补充速度快，我们不知道有多少材料，也不知道从哪里开采。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，并增加非法活动的可能性。按照目前的开采速度，到本世纪中叶，需求可能会超过供应。这些材料的重要性要求对沙资源进行监测，并全面了解沙通量和开采-包括法律的和非法的-以促进和确保负责任地开采和今后可持续地利用这些材料。该研究计划将通过两个主要研究目标来研究人类活动对沉积物的压力。目标一：采用遥感方法确定采矿地点，并审查可能对生态、当地基础设施和人类生计产生深远影响的潜在冲突以及与自然环境的协同作用，重点是非洲。总的目标是评估和了解开采活动，并建立一个空间概况的采砂及其与人类和自然的相互联系。目标二的重点是了解控制冰川融化沉积物流向海岸的北极高纬度过程。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。 我的研究项目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1b增长到2050年的2.4亿，以及在北极，气候变化特别明显。具体目标是：一）研究景观影响日益增长的全球需求的沉积物，重点是人口日益增加的非洲大陆和二）限制沉积物的动态和通量从冰覆盖的地区在加拿大北极海岸。以非洲为重点的研究可以在将住房和基础设施发展联系起来时，在地球健康科学和城市研究方面取得突破，这对预测未来的城市增长至关重要。此外，它可以改善环境保护行动的基础，这些行动未能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、当地社会和利益相关者在这些快速变化的环境中规划未来基础设施和整体生计稳定性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.