RAPID: Biogeochemical effects of fire ash deposition to the coastal ocean, in response to the 2017 Southern California fires

沿海地区的大规模野火导致火山灰落入海洋，影响未知。火山灰含有化学元素和物质，可以促进表层海洋中微生物的生长。自2017年12月4日以来，托马斯大火已经烧毁了南加州超过24万英亩的土地。大风将烟雾、火山灰和煤烟带到圣巴巴拉海峡上空1000多公里处。通过研究2017年的托马斯大火，这个快速项目的学术价值集中在火山灰供应对沿海海洋生态系统的影响上。这是通过实验和环境测量相结合的方式实现的，包括乘坐R/V Sally Ride对受影响区域进行海洋考察。该奖项的更广泛影响包括对超过12名研究生的船上培训，以及就托马斯大火对沿海海洋的影响提供洞察力。大规模野火可以通过沉积和径流过程将陆地生态系统与沿海海洋生态系统耦合起来。2017年12月4日开始的托马斯大火已经烧毁了超过24万英亩的土地，持续的离岸大风产生了浓烟、火山灰和煤烟，延伸到离岸1000多公里的地方。这一不幸的情况为研究火山灰沉积对沿海海洋的影响提供了机会。这项研究需要一系列孵化实验和测量，旨在评估火山灰沉积对沿海海洋生物地球化学的影响。具体地说，这项研究测试了一种假设，即野火产生的颗粒物沉积到沿海海洋会影响上层水柱的浮游生物群落，提供营养物质促进浮游植物的繁殖，将溶解的有机碳淋溶到供养异养细菌的表层水域，并作为下沉颗粒物的来源在水柱中更深地供养异养细菌种群。这些假设通过海上和国内实验室的一系列实验，以及通过船上测量和对从受影响水域收集的样本进行分析来检验。

Massive wildfires in coastal regions cause ash to fall into the ocean, with unknown impacts. Ash contains chemical elements and materials that can encourage the growth of microscopic organisms in the surface ocean. The Thomas Fire has burned over 240,000 acres in southern California since Dec 4, 2017. The winds have carried a plume of smoke, ash and soot more than 1000 km over the Santa Barbara Channel. The intellectual merit of this RAPID project focuses on the impact of fire ash supply to coastal ocean ecosystems, by studying the 2017 Thomas Fire. This is achieved through a combination of experiments and environmental measurements, including an oceanographic expedition to the affected area aboard the R/V Sally Ride. The broader impacts of this award include the shipboard training of more than twelve graduate students as well as providing insight as to effects of the Thomas Fire on the coastal ocean.Massive wildfires can couple terrestrial ecosystems to coastal ocean ecosystems through depositional and runoff processes. The Thomas Fire, which began on Dec 4, 2017, has burned over 240,000 acres and the persistent offshore winds created a plume of smoke, ash and soot that extended over 1000 km off shore. This unfortunate circumstance provides an opportunity to investigate the impact of ash deposition on the coastal ocean. This research entails a series of incubation experiments and measurements designed to assess the impact of fire ash deposition on the biogeochemistry of the coastal ocean. Specifically, the research tests the hypothesis that the deposition of wildfire-derived particulate matter to the coastal ocean impacts the planktonic communities of the upper water column, providing nutrients that facilitate blooms of phytoplankton, leaching dissolved organic carbon to surface waters that feeds heterotrophic bacterial populations, and serving as a source of sinking particulate matter that feeds heterotrophic bacterial populations deeper in the water column. These hypotheses are tested through a series of experiments at sea and in the home laboratories, and through shipboard measurements and analysis of samples collected from impacted waters.