RAPID: Resolving higher trophic-level change within the northern Gulf of Mexico ecosystem as a consequence of the Deepwater Horizon oil spill

学术价值：2010年4月22日，半潜式钻井平台深水地平线在墨西哥湾北部沉入近1200米深的水中。在几次试图关闭一个失败的防喷阀后，很明显每天都有大量的石油被释放出来。对未披露的化学分散剂的预先批准是基于对分散剂在有限区域和海面上的有限时间的应用的了解。在地面和通过直接注入1200米深的井口泄漏，使用了前所未有的数量的分散剂。其结果是释放出大量但未量化的可用于微生物降解的有机碳。到目前为止，还没有计划理解由于分散剂的大量应用或由此导致的石油或释放的化合物在水柱中的重新分布而导致的功能生态系统基线变化。科学家提出了这样的问题：这些资源(异养微生物与自养浮游植物)的基线变化是渗透到经典的食物网中，还是主要留在微生物网中？如果材料进入传统的食物网，它会偏爱鱼类还是胶状浮游动物？在短期和长期内理解这一点都是至关重要的，因为次级生产者代表初级生产和较高营养水平(例如食鱼鱼)之间的主要联系，通过这些水平能量(和污染物)被并入食草动物食物网。蒙蒂·格雷厄姆将与同事们合作一个项目，旨在描述墨西哥湾北部远洋系统在生态系统层面的变化。这一努力将具体地为单独供资的空间部分贡献一个时间部分。该小组将使用中上层滤食性无脊椎动物(水母)和脊椎动物(浮游鱼)的肠道含量和碳/氮稳定同位素比率进行营养评估。这些信息将与过去两年在密西西比河以东和以西受泄漏影响地区收集的SI和GUT内容信息进行比较。布罗德影响Dauphin岛海洋实验室的独特组织方式是提供从幼儿园(发现大厅计划)到博士(大学计划)的教育经验。这一快速项目将立即为现有的博士生伊莎贝拉·达安布拉女士(南阿拉巴马大学海洋科学系)提供教育方面的好处。世卫组织目前正在利用碳和氮的稳定同位素研究近岸中上层群落的营养结构。此外，一位新的科学家罗布·康登博士将于6月份开始工作，专门研究微生物/碎屑组分与食物链上游生物之间的营养交换。此外，这项研究将对重大的、长期的石油泄漏对更广泛的食物链影响产生影响，而不仅仅是对生态系统的简单严重破坏。

Intellectual Merit:On April 22, 2010, the semi-submersible drill platform Deepwater Horizon sank in nearly 1,200 m of water in the northern Gulf of Mexico. After several attempts to close a failed blowout preventer valve, it became clear that tremendous amount of oil was being released each day. Pre-approval of undisclosed chemical dispersants was made based on knowledge of the dispersant application over limited areas and for limited time at the sea surface. An unprecedented volume of dispersant has been applied both at the surface and through direct injection into the wellhead leak at 1,200 m depth. The result is the release of large, but unquantified concentrations of organic carbon available for microbial degradation. To date, there is no plan for understanding functional ecosystem baseline shifts as a consequence of this magnitude of application of dispersants or the resulting re-distribution of oil or released compounds within the water column.Scientists posed the questions: Do these baseline shifts in resource (heterotrophic microbes versus autotrophic phytoplankton) permeate through the classical food web or remain largely within the microbial web? If material enters the classical food web, does it favor fish or gelatinous zooplankton? It is vital to understand in this in both the short- and long-term because secondary producers represent the major link between primary production and higher trophic levels (e.g., piscivorous fish) by which energy (and contaminants) are incorporated into grazer food webs.Dr. Monty Graham will work with colleagues on a project aimed to characterizing ecosystem-level changes to the pelagic system of the northern Gulf of Mexico. This effort will specifically contribute a temporal component to a separately funded spatial component. The group will employ a trophic assessment using both gut contents and Carbon/Nitrogen stable isotope ratios of pelagic filter-feeding invertebrates (jellyfish) and vertebrates (planktivorous fish). These will be compared to SI and gut content information collected over the previous two years in the spill-impacted area east and west of the Mississippi River.Broader impacts The Dauphin Island Sea Lab is uniquely organized to provide educational experiences from kindergarten (Discovery Hall Programs) through Ph.D. (University Programs). This RAPID will provide an immediate educational benefit to an existing Ph.D. student, Ms. Isabella D'Ambra (University of South Alabama, Marine Sciences Dept.) who is currently working on the trophic structure of nearshore pelagic communities using stable isotopes of carbon and nitrogen. In addition, one new scientist, Dr. Rob Condon will begin employment in June specifically to address trophic exchanges between microbial/detritus fractions to upper food-chain organisms. Moreover, this study will have an impact on the wider food-chain impacts of a major, chronic oil spill beyond what is noted by the simple acute damage to ecosystems.