Collaborative Research: Ecosystem dynamics of Western Pacific hydrothermal vent communities associated with polymetallic sulfide deposits

热液喷口在西太平洋很常见，在许多地质、地球化学和生物方面与大洋中脊上的热液喷口有明显的不同。构建西太平洋热泉群落的过程，如物理和化学条件随时间变化的程度、生物在热液热泉区之间的扩散以及共生体及其动物宿主的生理能力，人们知之甚少。然而，在西太平洋活跃的热液喷口，大规模的多金属硫化物矿床工业开采迫在眉睫。2005年和2006年，在东劳扩散中心建立了19个长期研究点，通过对活动和不活动流区、硫化物烟囱和熔岩上的动物群落进行高分辨率摄影，并在这些摄影上绘制空间离散的物理和化学环境测量图。在接下来的一年里，我们将重新访问这些研究地点，获得类似分辨率的数据，并结合对关键物种生理学的详细研究，这将大大增加我们对动物群生理学和这些群落如何应对变化的理解。由此产生的数据将提供关于该地区特有的动物和群落的重要信息，这些信息对于预测和减轻采矿活动对这些生态系统的影响以及为监测采矿后可能恢复的计划提供信息至关重要。为了确保西太平洋岛民在整个项目期间都参与其中，当地科学家将参与实地考察，在港口停靠时向学生和公众进行国内演讲，并通过太平洋共同体秘书处（SPC）的地球科学部门将研究结果传达给当地资源管理者。主要研究人员也支持在海洋学家之间促进更大的“开放获取和合作”，在这次考察中，将使用远程呈现来试验两种不同的合作模式，这些模式以及由此产生的科学见解将被发表，以传播这一努力的结果。最后，将与哈佛自然历史博物馆（HMNH）合作，开发一个展示模块和课程课程，展示自然和人为干扰对生物多样性的影响。它将以高分辨率图像、动物和矿物学样本以及深海研究技术为特色。启用网络的信息亭将允许访问者更深入地研究主题材料。HMNH每年吸引20万游客，其中包括3.3万名学生（K-12）和他们的老师，以及来自世界各地的游客。资助的全息生物（共生体及其动物宿主）生理学和分布、群落结构和随时间变化、遗传连通性和全息生物生态系统工程的相互关联研究将显著增加我们对热液喷口生态系统总体结构过程的理解，特别是西太平洋的生态系统。在拟议的研究区域内，劳盆地内的喷口田彼此相对靠近，没有已知的生物扩散障碍，并且在地质环境和物理化学条件下跨越明显的区域梯度。这个自然实验室是火山口动物群多样性的家园，十年前在这里建立了长期研究地点，为获得对火山口动物群的生态和生理特征以及构建这些群落的过程的广泛新见解提供了机会。因此，该项目将A)通过获取新的高分辨率、共同注册的地质、化学和生物地图，并将其与2005年、2006年和2009年获得的可比分辨率数据进行比较，确定劳盆地火山口十年来自然物理、化学和生物变化的速率和模式；B)通过将寄主和共生体的遗传特征与船上生理测量和基因表达研究以及物理化学微生境特征相结合，评估共生体生理学的作用——特别是它们对以前未测量的关键能源的使用——在全息生物的实现分布中；C)量化不同全息物对周围环境的影响，方法是将重复的物理-化学条件的空间综合测量耦合到所有的集合；D)评估劳盆地种群遗传连通性对全息生物跨区域地质和地球化学梯度分布的影响。它们将为多种共生体在其动物宿主分布和相关群落结构中的作用提供新的和普遍适用的见解。这些努力也将限制遗传连通性、环境化学和全息生物能力在沿着这一传播中心构建社区中的作用。此外，通过共同登记的动物标本和现场地球化学测量，研究人员将对全息生物聚集对漫射流的地球化学通量的影响程度进行一级估计，漫射流约占所有喷口地球化学通量的50%。最终，这项工作将为西太平洋生物地理省的喷口场和群落的动态以及控制这些模式的潜在生理和生态因素提供关键和可靠的数据。

Hydrothermal vents are common in the Western Pacific, and are markedly different in many geological, geochemical, and biological aspects from the much better known hydrothermal vents on mid-ocean ridges. The processes that structure western Pacific vent communities, such as the extent to which physical and chemical conditions change over time, the dispersal of organisms among hydrothermal vent fields, and the physiological capacities of the symbionts and their animal host are poorly understood. And yet, large-scale industrial mining of polymetallic sulfide deposits at active hydrothermal vents is imminent in the Western Pacific. In 2005 and 2006, 19 long term study sites were established on the Eastern Lau Spreading Center by generating high resolution photomosaics of animal communities in both active and inactive flow areas and on both sulfide chimneys and on lavas, and mapping spatially discrete physical and chemical environmental measurements on to these photomosaics. Revisiting these study sites and acquiring data of comparable resolution in the coming year, combined with detailed studies of the physiology of key species, will significantly increase our understanding of the physiology of the fauna and how these communities respond to change. The resulting data will provide crucial information on the fauna and communities endemic to this region that is critical for predicting and mitigating the effects of mining activities on these ecosystems, and for informing plans for monitoring potential recovery post-mining. To ensure that Western Pacific Islanders are engaged throughout the duration of our program, local scientists will be included in the fieldwork, in-country presentations to students and the general public will be given in association with port stops, and findings will be communicated to local resource managers through the Geoscience Division of the Secretariat of the Pacific Community (SPC). The principal investigators are also proponents of fostering greater "open access and collaboration" among oceanographers, and telepresence will be used during this expedition to experiment on two different models of collaboration, which - along with the resulting scientific insights - will be published to disseminate the results of this effort. Finally, in collaboration with the Harvard Museum of Natural History (HMNH), an exhibit module and course curricula will be developed presenting the effects of both natural and anthropogenic disturbance on biodiversity. It will feature high-resolution imagery, animal and mineralogical samples, and deep-sea research technologies. Web-enabled kiosks will allow visitors to delve deeper into the subject material. The HMNH attracts 200,000 visitors each year, including 33,000 students (K-12) and their teachers, as well as visitors from around the world. The funded interlinked studies of holobiont (symbionts and their animal host) physiology and distribution, community structure and change over time, genetic connectivity, and holobiont ecosystem engineering will significantly increase our understanding of the processes structuring hydrothermal vent ecosystems in general, and those of the Western Pacific in particular. Vent fields in the proposed study area within the Lau Basin are located in relative proximity to one another with no known barriers to biological dispersal and span a pronounced regional gradient in both geological setting and physico-chemical conditions. This natural laboratory, that is home to a significant diversity of vent fauna and where long-term study sites were established a decade ago, presents an opportunity to gain broad new insights into the ecological and physiological characteristics of the vent fauna and the processes that structure these communities. Accordingly, the project will A) determine the rates and patterns of natural physical, chemical, and biological changes at vents in the Lau Basin over a decadal time period by acquiring new high-resolution, co-registered geological, chemical and biological maps and comparing these with data of comparable resolution acquired in 2005, 2006, and 2009; B) evaluate the role of symbiont physiology -in particular their use of key energy sources not previously measured- in the realized distribution of the holobionts by coupling genetic characterization of host and symbionts with shipboard physiological measurements and gene expression studies, and physico-chemical microhabitat characterization; C) quantify the effects of different holobionts on the surrounding environment by coupling repeated spatially integrated measurements of physico-chemical conditions to all collections and; D) assess the influence of genetic connectivity of populations in the Lau Basin on the distribution of holobionts across regional gradients in geology and geochemistry. They will provide new and generally applicable insights on the role of multiple symbionts in both the distribution of their animal hosts and in structuring associated communities. These efforts will also constrain the roles of genetic connectivity, environmental chemistry, and holobiont capabilities in structuring communities along this spreading center. Moreover, through co-registered animal collections and in situ geochemical measurements, the investigators will develop first-order estimates of the extent to which holobiont aggregations affect geochemical flux from diffuse flows, which accounts for ~50% of all vent geochemical flux. Ultimately, this effort will provide critical and robust data on the dynamics of vent fields and communities in the western Pacific biogeographic province, as well as on the underlying physiological and ecological factors governing these patterns.