OFI SF7 Assessing the effects of Ocean Alkalinity Enhancement (OAE) on the marine microbiome

海洋碱度增强(OAE)在拟议的基于海洋的二氧化碳去除(Ocean-CDR)方法中正迅速获得支持。从理论上讲，OAE是一种CDR方法，对海洋生态系统的不利影响应该是最小的，同时有可能在受影响的海洋区域(例如珊瑚礁)恢复人为二氧化碳加剧的海洋酸化的有害影响。然而，由于海洋微生物群(浮游植物、细菌和古生物)处于食物链的底部，因此迫切需要获得有关海洋微生物群(浮游植物、细菌和古生物)的实验数据来证明OAE对海洋生物的影响。行星技术公司正在开发基于OAE的CDR，并计划将贝德福德盆地作为试点研究地点。申请人建议进行生物测定实验，以评估OAE对微生物组的潜在影响。生物测定实验包括短期(最长72小时)与贝德福德盆地自然微生物群落的瓶子培养，在为期12个月的四季中，分别添加(处理)和不添加(对照)碱性底物氢氧化镁。从对照和处理培养的微生物群中提取的核酸(DNA和RNA)的高通量测序将相互比较，并与正在进行的时间序列采样获得的初始群落进行比较。实验结果和数据库将与行星和其他股东共享，以建立环境评估的基线，并指导其方法的初步试验，以最大限度地减少OAE对生物生态系统的潜在不可预见的影响。

Ocean alkalinity enhancement (OAE) is rapidly gaining support within the proposed ocean-basedcarbon dioxide removal (ocean-CDR) approaches. Theoretically, OAE is a CDR approach that should have minimal adverse impact on the marine ecosystem, while having the potential torestore the detrimental effects of anthropogenic CO2-enhanced ocean acidification in impacted regions of the ocean (e.g. coral reefs). However, there is a lack of experimental datadocumenting the OAE effect on marine life and an urgent need to obtain this data for the marine microbiome (phytoplankton, bacteria and archaea) given their position at the base of the foodchain. Planetary Technologies is developing OAE-based CDR and is planning to use BedfordBasin as a pilot study site. The applicant proposes to conduct bioassay experiments to assess the potential effects of OAE on the microbiome. The bioassay experiments consist of short-term (up to 72 hours) bottle-incubations with natural microbial communities from the Bedford Basin with (treatment) and without (control) the addition of the alkaline substrate magnesium hydroxide,during four seasons over a 12-month period. High-throughput sequencing of nucleic acids (DNA and RNA) extracted from the microbiome of the control and treatment incubations will becompared to each other and to the initial community obtained from ongoing time-seriessampling. The experimental results and database will be shared with Planetary and othershareholders to establish a baseline for environmental assessment and guide the initial trials oftheir approach to minimize the potential unforeseen effects of OAE on the living ecosystem.