Seabed Mining And Resilience To EXperimental impact

点击翻译按钮获取中文摘要

Over a 6 million square km region of the central Pacific ocean, at abyssal depths of almost five thousand metres, lies a vast mineral resource in the form of small potato-sized deposits called polymetallic nodules. They are highly-enriched in metals of importance for industry, including the development of new sustainable technologies. Although the region lies in international waters, countries have now signed 16 exploration contracts with a UN-organised international regulator and the United Kingdom is sponsor to two of these, covering an area more than the size of England. It is a requirement of both the regulator and the sponsoring state to ensure that serious harm is avoided to the marine ecosystem in this region - a hitherto untouched deep-sea wilderness. Developing a sustainable approach to polymetallic nodule mining is a challenge as the nature and importance of the Pacific abyssal ecosystem is largely unknown, as are the capacity of the ecosystem to cope with and recover from mining impacts. Our project aims to provide the critical scientific understanding and evidence-base to reduce the risks of this industrial development, taking advantage of two new and unique opportunities to solve these problems in a single programme. Firstly, the UK contractor that holds the UK-sponsored exploration contract (UK Seabed Resources) is planning a mining test in 2023, which will allow us to test the immediate impacts of a seabed mining vehicle for the first time. Secondly, as a partner in the first full-scale mining test done in 1979, they have been able to release new data on the location and results of a 40-year old large-scale mining operation. Our project team have secured access to data and test plans, to allow detailed experimental evaluation of impact and recovery from realistic mining disturbance on a decadal scale of vital relevance to understanding the long-term sustainability of deep-sea mining.The project aims to better understand the ecosystem in the Pacific abyss and how the different components interact and interconnect. We will start by assessing the water and its dynamic flows over time and space. This complex physical environment will be monitored for a year to capture its variabilities, particularly "storm events" near the seabed. We will use this to make predictions about where the sediment plume generated by mining will be transported and settle back to the seafloor. We then assess the linkages between the water, sediment surface and sub sediments, evaluating the natural cycling of nutrients and metals that is important to maintain ecosystem health. The impacts of mining and recovery of these processes will be assessed. Mining will lead to changes in the structure of the seabed, its shape and the physical nature of the sediments, which will be mapped and linked to biological patterns. The biological processes that lead to these patterns will be assessed by detailing the life histories and reproduction of the organisms present and their connectivity between areas near and far, and then determining their role in maintaining structured communities of life, a high biodiversity and a functioning food web. We will then evaluate the functions in the ecosystem that these organisms provide, which help maintain a healthy ecosystem. The impact of mining and recovery of all these patterns and processes will be determined using our experimental areas to assess the biological and functional consequences of disturbance in the deep sea. These changes are likely complex, so a range of mathematical models will be used to better understand and predict the consequences of mining activities at larger time and space scales. Such predictive power, along with the evidence from the scientific assessment, will provide information that is critical for understanding and reducing the environmental risk of future mining activities.