Effects of Disturbance and Larval Supply on Communities at Hydrothermal Vents

概述：该项目的长期目标是了解干扰对喷口系统物种发生和区域多样性的影响。研究人员正在通过对幼虫的扩散和定植过程进行实地研究，并通过与理论生态学家合作来努力实现这一目标。本项目调查了在最近东太平洋海隆(EPR)灾难性喷发之前和之后对喷口进行了长达十年的监测所收集的一组独特的现场观测。具体目标是确定演替是否是确定性的(或者是否存在替代的稳定状态？)，以及一个喷口区域的干扰是否会在更大的空间尺度上影响群落结构。回答这些问题需要对幼虫在喷口之间的交换以及先驱殖民者对演替轨迹的影响进行表征。方法是描述EPR上三个喷口地点的幼虫和殖民地的物种组成：一个受到喷发干扰(北纬9度50分)，两个保持不变(北纬9度47分和北纬9度30分)。研究人员处理这些样本的时间已经不多了，因为它们会随着时间的推移而退化，而且这些样本有可能失去对物种鉴定至关重要的形态细节。该奖项有适度的资金，专门专注于物种鉴定和计数，而不是试图与模型或种群遗传分析相联系。这些将在晚些时候到来。智力价值：自20世纪70年代末发现喷口以来，喷口群落如何在零星、短暂的栖息地中生存的问题一直引起了科学家的兴趣。幼虫连通性对区域尺度上的元群落动态的影响的必要综合仍然是我们所不能企及的。这个项目致力于通过描述幼虫交换和群落演替的关键方面来实现这一合成，这些关键方面都是在经过充分研究的EPR上进行的。这项研究对全球喷口系统具有普遍的适用性，因为它挑战了喷口演替是确定性的假设，并有助于我们理解幼虫连通性的空间尺度。这项研究将产生关于幼虫交换和群落弹性的数据，这正是集合种群建模、预测喷口群落对海底采矿等人为事件的反应以及为马里亚纳海沟国家海洋保护区的管理工作提供信息所需的数据。广泛的影响：调查者将通过伍兹霍尔著名的伙伴关系教育计划(PEP)招募有前途的本科生，通过招募代表不足的少数族裔学生来扩大研究的影响。PEP的目标是增加海洋和环境科学的多样性；它由该地区的6个科学机构赞助。预算中的资金将在两个夏天让更多的学生加入该项目，特别是致力于喷口生态研究。此外，Pi Mullineaux将继续她在教育和外展方面的长期努力，通过教授研究生课程，通过WHOI SSF计划让本科生参与喷口研究，并通过伍兹霍尔科学和技术教育伙伴关系将海洋科学过渡到当地社区。

Overview: The long-term aim of this project is to understand the effects of disturbance on species occurrence and regional diversity in vent systems. The investigator is working toward that goal by conducting field studies on larval dispersal and colonization processes, and by collaborating with theoretical ecologists. The present project investigates a unique set of field observations gathered from decade-long monitoring of vents before and after a recent catastrophic eruption on the East Pacific Rise (EPR). The specific objectives are to determine whether succession is deterministic (or are there alternative stable states?), and whether disturbance at one vent field can influence community structure on a larger spatial scale. Answering these questions requires characterization of larval exchange between vents and of the effect of pioneer colonists on successional trajectory. The approach is to characterize species composition of larvae and colonists at three vent sites on the EPR: one that was disturbed by the eruption (9 degrees 50 minutes N) and two that remained undisturbed (9 degrees 47 minutes N and 9 degrees 30 minutes N). The investigators are running out of time to process the samples, because they degrade over time and the specimens are at risk of losing morphological detail which is critical for species identification. This award has modest funding to focus specifically on species identification and enumeration, without attempting to interface with models or population genetic analyses. These will come later. Intellectual Merit: The question of how vent communities persist despite living in patchy, ephemeral habitat has intrigued scientists since the discovery of vents in the late 1970s. A necessary synthesis of the influence of larval connectivity on metacommunity dynamics at the regional scale continues to elude us. This project works toward that synthesis by characterizing critical aspects of larval exchange and community succession at vents on the well-studied EPR. This study has general application to vent systems globally because it challenges the assumption that vent succession is deterministic, and it will contribute to our understanding of spatial scales of larval connectivity. The data on larval exchange and community resilience that will result from this study are precisely the kind needed for metapopulations modeling, for prediction of vent community response to anthropogenic events such as seafloor mining, and to inform management efforts at the Marianas Trench Marine National Monument.Broader Impacts: The investigator will broaden the impact of this research by engaging under-represented minority students into research through recruitment of promising undergraduates via the well-established Partnership Education Program (PEP) in Woods Hole. The objective of PEP is to increase diversity in the Ocean and Environmental Sciences; it is sponsored by 6 scientific institutions in the region. Funds are budgeted to bring additional students into the program in two summers, specifically to work on vent ecological research. In addition, PI Mullineaux will continue her long-term efforts at education and outreach through teaching graduate courses, engaging undergraduates into vents research through the WHOI SSF program, and transitioning ocean science to the local community through the Woods Hole Science and Technology Education Partnership.