Changing Concentrations of Methyl Halides, Nonmethane Hydrocarbons, Organic Sulfur Species, and Alkyl Nitrates in Response to Iron Fertilization during SOFeX

SOFeX 过程中卤代甲烷、非甲烷烃、有机硫物质和硝酸烷基酯的浓度变化对铁施肥的响应

• 批准号: 0327198
• 负责人: Oliver Wingenter
• 金额: $ 17万
• 依托单位: New Mexico Institute of Mining and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0327198&HistoricalAwards=false
• 关键词: Changing; Concentrations; Methyl; Halides; Nonmethane

ABSTRACTOCE-0327198Marine production and consumption of volatile organic carbon (VOC) species, including methyl halides, nonmethane hydrocarbons (NMHCs), alkyl nitrates, and dimethyl sulfide (DMS), by phytoplankton and other microorganisms have an impact on stratospheric ozone and global climate. Several VOCs were sampled from surface ocean water and the lower atmosphere for the first time during an iron (Fe) enrichment experiment. The Southern Ocean Iron Experiment (SOFeX) was conducted between January-February 2002, and involved the research vessels Revelle, Melville, and Polar Star. An extensive suite of chemical, physical, and biological measurements were made in order to observe the effects of iron fertilization on marine organisms and the extent of carbon sequestration in two high nutrient, low chlorophyll (HNLC) regions in the Southern Ocean. Previous iron enrichment experiments indicate that primary productivity is limited by trace amounts of iron in certain HNLC regions. During SOFeX, two areas were fertilized, one north of the Antarctic Polar Front and the other south of the front. Roughly one quarter of the ocean.s surface waters are HNLC and may be iron limited. Much of this area is in the Southern Ocean, making this region promising for reducing global warming by sequestering additional oceanic carbon by iron fertilization.To date, researchers at the New Mexico Institute of Mining and Technology have completed VOC analyses of 420 seawater samples from SOFeX. With support from this project, they will complete the remaining 98% of the analysis, so that each peak representing each compound on 2700 individual chromatograms can be visually checked, normalized to the standards, and corrected for disequilibria in the equilibrator. The U.S. and other governments are seeking solutions to mitigate global warming. Some proposals involve climate engineering such as iron fertilization. Prudence dictates that before any large-scale oceanic iron fertilization takes place, its impact on the marine production of climatically relevant compounds such as VOCs must be assessed. VOC results from the SOFeX field study will better inform policy makers and society on the coupling between the marine biosphere and the atmosphere. This knowledge is imperative in order to more fully understand the climatic ramifications of proposed large-scale iron fertilization/carbon sequestration.

海洋浮游植物和其他微生物产生和消耗的挥发性有机碳（VOC）物质，包括卤代甲烷、非甲烷碳氢化合物（NMHCs）、硝酸烷基酯和二甲基硫醚（DMS），对平流层臭氧和全球气候有影响。 在铁（Fe）富集实验期间，首次从表层海水和低层大气中采集了几种VOCs。 南大洋铁实验（SOFeX）是在2002年1月至2月间进行的，研究船包括Revelle、梅尔维尔和极地星星。 一套广泛的化学，物理和生物测量，以观察铁施肥对海洋生物的影响和在两个高营养，低叶绿素（HNLC）地区在南大洋的碳封存的程度。以前的铁富集实验表明，初级生产力是有限的微量铁在某些HNLC地区。 在SOFeX期间，有两个地区被施肥，一个在南极极锋以北，另一个在极锋以南。大约四分之一的海洋表面沃茨是HNLC，可能是铁有限的。该地区大部分位于南大洋，这使得该地区有希望通过铁肥封存额外的海洋碳来减少全球变暖。迄今为止，新墨西哥州矿业与技术研究所的研究人员已经完成了对SOFeX中420个海水样本的VOC分析。在该项目的支持下，他们将完成其余98%的分析，以便可以目视检查2700个单独色谱图上代表每种化合物的每个峰，标准化为标准品，并校正平衡中的不平衡。 美国和其他国家的政府正在寻求缓解全球变暖的解决方案。 一些建议涉及气候工程，如铁施肥。 为谨慎起见，在任何大规模的海洋铁肥化发生之前，必须评估其对海洋产生的与气候相关的化合物（如挥发性有机化合物）的影响。SOFeX实地研究的挥发性有机化合物结果将更好地为决策者和社会提供有关海洋生物圈和大气之间耦合的信息。 为了更充分地了解拟议的大规模铁施肥/碳固存的气候后果，这种知识是必不可少的。