Subaerial volcanism is a potentially major contributor to oceanic iron and manganese cycles
Subaerial volcanism is a potentially major contributor to oceanic iron and manganese cycles
复制标题
DOI：
10.1038/s43247-022-00389-7
复制
发表时间：
2022-03-14
影响因子：
7.9
通讯作者：
Jones, Morgan T.
中科院分区：
文献类型：
--
作者：
Longman, Jack;Palmer, Martin R.;Jones, Morgan T.
海洋表面微量元素铁和锰的可用性影响海洋的初级生产力和碳循环。火山灰富含铁和锰，但全球通过火山灰沉积向海洋提供这些营养物质的限制很少。在这里，我们使用来自10个火山区域的海洋沉积物火山灰成分数据和地面火山喷发量来估计全球火山灰驱动的营养通量。利用蒙特卡罗模拟，我们估计火山源中溶解铁和锰的平均通量分别在50至500（中位数180）和0.6至3.2（中位数1.3）Gmol /年（-1）之间。大部分元素释放发生在早期成岩作用中，表明富含灰分的陆架沉积物可能是水中铁和锰的重要供应者。估算的火山灰驱动通量与风成通量的量级相似。我们认为，海底火山活动是向全球海洋提供这些微量营养素的重要来源，但未得到充分认识。根据基于火山灰组成和喷发量数据的蒙特卡罗模拟，陆上火山活动可能通过富含铁和锰的火山灰沉积为海洋表面提供微量营养素的重要来源。
Surface ocean availability of the micronutrients iron and manganese influences primary productivity and carbon cycling in the ocean. Volcanic ash is rich in iron and manganese, but the global supply of these nutrients to the oceans via ash deposition is poorly constrained. Here, we use marine sediment-hosted ash composition data from ten volcanic regions, and subaerial volcanic eruption volumes, to estimate global ash-driven nutrient fluxes. Using Monte Carlo simulations, we estimate average fluxes of dissolved Iron and Manganese from volcanic sources to be between 50 and 500 (median 180) and 0.6 and 3.2 (median 1.3) Gmol yr(-1), respectively. Much of the element release occurs during early diagenesis, indicating ash-rich shelf sediments are likely important suppliers of aqueous iron and manganese. Estimated ash-driven fluxes are of similar magnitude to aeolian inputs. We suggest that subaerial volcanism is an important, but underappreciated, source of these micronutrients to the global ocean.Subaerial volcanism may provide an important source of micronutrients to the surface ocean through the deposition of iron and manganese rich ash, according to Monte Carlo simulations based on ash composition and eruption volume data.